Internet & Network

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‫ﺻﻔﺤﻪ‬

‫ﺑﺨﺶ ﺳﻮﻡ ‪ :‬ﺍﻳﻨﺘﺮﻧﺖ‬

‫ ﻣﻌﺮﻓﯽ ﺷﺒﮑﻪ ﭘﻬﻨﺎﻭﺭ ﺟﻬﺎﻧﯽ ) ‪۶........................................( World Wide Web‬‬‫‪ -‬ﺯﻳﺮ ﺳﺎﺧﺖ ﺍﻳﻨﺘﺮﻧﺖ ‪۴۷...............................................................................................‬‬

‫‪۵۶.......................................................................................................................ISP -‬‬

‫ ‪۶۰.....................................................................................................................DSL‬‬‫‪۶۷.................................................................................................................VDSL -‬‬

‫ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﻱ‪۷۲.................................................................................................‬‬‫ ‪۷۴..................................................................................................................VOIP‬‬‫‪ -‬ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ‪۸۱...............................................................................................‬‬

‫ ﻳﺎﺩﮔﻴﺮﻱ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ‪۹۴...............................................................................................‬‬‫ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ‪۱۰۱..................................................................................................‬‬‫‪ -‬ﺭﺍﺩﻳﻮ ﺍﻳﻨﺘﺮﻧﺘﻲ‪۱۰۹........................................................................................................‬‬

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‫ﺻﻔﺤﻪ‬

‫ﺑﺨﺶ ﭼﻬﺎﺭﻡ ﺷﺒﮑﻪ‬

‫ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‪۱۱۴.............................................................................................‬‬‫‪-‬‬

‫ﺷﺒﮑﻪ ﻭﺍﻧﻮﺍﻉ ﺁﻥ‪۱۲۶......................................................................................................‬‬

‫ ‪ MAC Address‬ﭼﻴﺴﺖ؟‪۱۲۹..................................................................................‬‬‫ ﻣﺪﻝ ﻣﺮﺟﻊ ‪۱۳۳....................................................................................................OSI‬‬‫‪۱۳۶......................................................................................................................OSI -‬‬

‫ ﻧﺤﻮﻩ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ‪۱۴۰............................................................................‬‬‫‪ -‬ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ‪۱۴۵.....................................................................................................‬‬

‫ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﭘﻮﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺭ ﻭﻳﻨﺪﻭﺯ‪۱۴۸.................................................................‬‬‫ ﭘﺮﻭﺗﮑﻞ ‪۱۶۰..................................................................................................TCP/IP‬‬‫‪ -‬ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﺍﻭﻝ (‪۱۶۹.....................................................‬‬

‫ ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﺩﻭﻡ (‪۱۷۵...................................................‬‬‫ ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﺳﻮﻡ (‪۱۸۳...................................................‬‬‫‪ -‬ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﭼﻬﺎﺭﻡ (‪۱۸۹................................................‬‬

‫ ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪) TCP/IP‬ﻗﺴﻤﺖ ﭘﻨﺠﻢ (‪۱۹۶...................................................‬‬‫‪۲۰۳...................................................................................................................DNS -‬‬

‫ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ‪۲۱۹............................................................................................. DNS‬‬‫ ﺍﺗﺮﻧﺖ ‪۲۲۷...................................................................................................................‬‬‫‪-‬‬

‫‪۲۴۰...................................................................................................................NAT‬‬

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‫‪۲۴۶...............................................................................................................VLAN‬‬

‫‪ -‬ﺷﺒﮑﻪ ﻫﺎﻱ ‪۲۵۰.................................................................................................VPN‬‬

‫ ﺍﺷﺘﺮﺍﮎ ﻣﻨﺎﺑﻊ ‪۲۶۱........................................................................................................‬‬‫‪3‬‬

‫ ﻫﺎﺏ ﻭ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺁﻥ ‪۲۷۱......................................................................................‬‬‫‪-‬‬

‫ﺳﻮﺋﻴﭻ ‪۲۷۵...................................................................................................................‬‬

‫ ﻣﻔﻬﻮﻡ ﺭﻭﺗﻴﻨﮓ ‪۲۹۳......................................................................................................‬‬‫ ﭘﺮﻭﺗﮑﻞ ﺭﻭﺗﻴﻨﮓ‪۲۹۵.....................................................................................................‬‬‫‪ -‬ﻓﺮﺁﻳﻨﺪ ﺭﻭﺗﻴﻨﮓ‪۲۹۷.......................................................................................................‬‬

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‫ﺭﻭﺗﺮ ‪۳۰۳.....................................................................................................................‬‬

‫ ﺭﺍﻩ ﺍﻧﺪﺍﺯﯼ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ‪۳۱۳.............................................................................................‬‬‫ ﺁﺷﻨﺎﺋﯽ ﺑﺎ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺭﻭﺗﺮ‪۳۱۷..................................................................................‬‬‫ ﺭﺍﻩ ﺍﻧﺪﺍﺯﯼ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ‪ :‬ﺍﻳﺠﺎﺩ ﻳﮏ )‪۳۲۴..................( Hyper Terminal Session‬‬‫ ﺁﺷﻨﺎﺋﯽ ﺑﺎ ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﯽ ﺭﻭﺗﺮ‪۳۲۸................................................................................‬‬‫ ﺁﺷﻨﺎﺋﯽ ﺑﺎ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﯼ ﺭﻭﺗﺮ‪۳۳۳...............................................................................‬‬‫ ﺭﻭﺗﺮ ﻭ ﺟﺎﻳﮕﺎﻩ ﺁﻥ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﯼ ‪۳۳۹............................................................WAN‬‬‫ ﺍﻧﻮﺍﻉ ﺭﻭﺗﺮ‪۳۴۶.............................................................................................................‬‬‫‪-‬‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ‪۳۵۰..................................................................................................‬‬

‫ ﭘﻴﮑﺮﺑﻨﺪﯼ ﺭﻭﺗﺮ ﻫﺎﯼ ﺳﻴﺴﮑﻮ‪۳۵۵.................................................................................‬‬‫ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ‪۳۶۴..........................................................................................‬‬‫‪ -‬ﺍﻧﻮﺍﻉ ﺷﺒﮑﻪ ﻫﺎﻱ ‪۳۷۰................................................................................Wireless‬‬

‫ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﺒﮑﻪ ‪۳۷۳.................................................................................Wireless‬‬‫ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﻣﻴﺰﺍﻥ ﺗﺄﺧﻴﺮ ‪۳۷۶.....................................................................................‬‬‫ ﺍﻧﻮﺍﻉ ﮐﺎﺑﻞ ‪۳۸۰............................................................................................................‬‬‫‪ -‬ﻓﻴﺒﺮ ﻧﻮﺭﻱ ‪۳۸۵............................................................................................................‬‬

‫ ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ‪۳۹۱...........................................................................................X-Over‬‬‫ ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ‪۳۹۵.........................................................................................Straight‬‬‫ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺧﻄﻮﻁ ‪۴۰۱....................................................................................T1‬‬‫‪4‬‬

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‫ﻣﻌﺮﻓﻲ ﺷﺒﻜﻪ ﭘﻬﻨﺎﻭﺭ ﺟﻬﺎﻧﻲ )‪(World Wide Web‬‬ ‫ﻗﺒﻞ ﺍﺯ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺏ‪ ,‬ﺭﻭﻳﺎﻱ ﺯﺍﻧﺪﺍ ﻣﻄﺮﺡ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﻭﻳﺎ ﺗﻤﺎﻣﻲ‬ ‫ﻋﻠﻮﻡ‪ ,‬ﻣﺴﺘﻨﺪﺍﺕ‪ ,‬ﺗﺼﺎﻭﻳﺮ‪ ,‬ﺻﻮﺕ‪ ,‬ﻭﻳﺪﺋﻮ ﻭ… ﺗﻮﺳﻂ ﻫﺮ ﻓﺮﺩ ﻛﻪ ﺩﺍﺭﺍﻱ ﻳﻜﺪﺳﺘﮕﺎﻩ ﻛﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺑﻮﺩ ﺩﺭ ﻫﺮ ﺯﻣﺎﻥ ﻭ ﻣﻜﺎﻥ ﺩ ﻟﺨﻮﺍﻩ‪ ,‬ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻮﺩ‪ .‬ﺯﺍﻧﺪﺍ‪ ،‬ﺭﻭﻳﺎﻱ" ﺗﺪﻧﻠﺴﻮﻥ " ﺍﺯ ﻳﻚ‬ ‫ﻛﺎﻣﭙﻴﻮﺗﺮ ﺧﻴﺎﻟﻲ ﺑﻮﺩ‪ .‬ﻭﻱ ﺩﻧﻴﺎﺋﻲ ﺭﺍ ﻛﻪ ﺩﺭ ﺁﻥ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻳﻖ ﺍﺑﺮ ﻣﺘﻦ ﻫﺎ ﻭ ﺍﺑﺮ ﺭﺳﺎﻧﻪ ﻫﺎ‬

‫ﺑﺼﻮﺭﺕ ﻳﻚ ﺷﺒﻜﻪ ﺗﺎﺭ ﻋﻨﻜﺒﻮﺗﻲ ﺑﻬﻢ ﻣﺘﺼﻞ ﻭ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻳﺪﻧﺪ‪ ,‬ﭘﻴﺶ ﺑﻴﻨﻲ ﻛﺮﺩﻩ ﺑﻮﺩ‪ .‬ﺩﺭ‬ ‫ﺍﻳﻦ ﺩﻧﻴﺎ ﺍﻃﻼﻋﺎﺕ ﺑﺼﻮﺭﺕ ﻳﻚ ﻛﺘﺎﺑﺨﺎﻧﻪ ﺟﻬﺎﻧﻲ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻦ‬

‫ﻛﺘﺎﺑﺨﺎﻧﻪ ﺟﻬﺎﻧﻲ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﺗﺎﺛﻴﺮ ﺷﮕﺮﻓﻲ ﺩﺭ ﺟﻮﺍﻣﻊ ﻣﺘﻔﺎﻭﺕ ﺑﺸﺮﻱ ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺩﺍﺷﺘﻪ ﻭ‬

‫ﻣﻨﺸﺎ ﺑﺮﻭﺯ ﺗﺤﻮﻻﺕ ﻋﻈﻴﻢ ﺩﺭ ﺣﻴﺎﺕ ﺑﺸﺮﻱ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﻧﺤﻮﻩ ﺷﻜﻞ ﮔﻴﺮﻱ ﻭ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻥ ﻭﺏ‬ ‫ﺯﺍﻧﺪﺍ ﻳﻚ ﺭﻭﻳﺎ ﺑﻮﺩ‪ ،‬ﻭﻟﻲ ﺍﻣﺮﻭﺯ ﺑﺎ ﻭﺍﻗﻌﻴﺘﻲ ﺑﻨﺎﻡ ﻭﺏ ﻣﻮﺍﺟﻪ ﻫﺴﺘﻴﻢ‪ .‬ﺑﻪ ﮐﻤﮏ ﻭﺏ‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ‪ ،‬ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﻣﺤﻞ ﺍﺳﺘﻘﺮﺍﺭ ﺑﻬﻢ ﭘﻴﻮﻧﺪ ﺧﻮﺭﺩﻩ ﻭ ﺍﻣﻜﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺩﺭﻳﺎﺋﻲ‬ ‫ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻛﻨﻨﺪﻩ ﻓﺮﺍﻫﻢ ﻣﻴﮕﺮﺩﺩ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻣﺎﻫﻴﺘﻲ ﻛﺎﻣﻼ" ﭘﻮﻳــﺎ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﻚ ﺩﺍﻳﺮﻩ ﺍﻟﻤﻌﺎﺭﻑ ﺑﺼﻮﺭﺕ ﺍﻳﺴﺘﺎ ﻣﻲ ﺑﺎﺷﻨﺪ ﻭﻟﻲ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻭﺏ ﺑﺼﻮﺭﺕ ﭘﻮﻳﺎ ﺑﻮﺩﻩ ﻭ ﺩﺍﺋﻤﺎ" ﺑﻬﻨﮕﺎﻡ ﻣﻴﺸﻮﻧﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻭﺏ ﻣﻴﺘﻮﺍﻥ ﺩﺭ‬ ‫ﺳﺮﻳﻌﺘﺮﻳﻦ ﺯﻣﺎﻥ ﻣﻤﻜﻦ ﺑﻪ ﺟﺪﻳﺪﺗﺮﻳﻦ ﺍﻃﻼﻋﺎﺕ ﺩﺳﺘﻴﺎﺑﻲ ﭘﻴﺪﺍ ﻛﺮﺩ‪.‬ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ‬

‫ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻛﻪ ﻫﺮ ﻛﺪﺍﻡ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺩﺭ ﻳﻚ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﻣﺤﻞ ﻣﺴﺘﻘﺮ ﻳﺎﺷﻨﺪ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ﺍﺳﺘﻔﺎﺩﻩ ﻛﻨﻨﺪﻩ ﻗﺮﺍﺭ ﻣﻴﮕﻴﺮﺩ‪ .‬ﻭﺏ ﭘﺘﺎﻧﺴﻴﻞ ﺑﺎﻻﻱ ﺧﻮﺩ ﺭﺍ ﻣﺪﻳﻮﻥ ﺩﻭ ﺗﻜﻨﻮﻟﻮﮊﻱ‬ ‫ﻣﺪﺭﻥ‪ " :‬ﺍﺑﺮ ﻣﺘﻦ ﻫﺎ")‪ (HyperText‬ﻭ" ﺍﺑﺮ ﺭﺳﺎﻧﻪ ﻫﺎ " )‪ (HyperMedia‬ﺍﺳﺖ‪ .‬ﺩﺭ‬

‫ﺍﺑﺮﻣﺘﻦ ﻫﺎ‪ ,‬ﺍﻃﻼﻋﺎﺕ ﻣﺮﺗﺒﻂ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺭﻭﺵ ﻣﺪﻭﻥ ﺑﻬﻢ ﭘﻴﻮﻧﺪ ﺯﺩﻩ ﻣﻴﺸﻮﻧﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﻴﻦ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﻣﻴﺘﻮﺍﻥ ﺑﺎ ﻫﺮ ﺭﻭﺵ ﺩﻟﺨﻮﺍﻩ ﻭ ﻃﻲ ﻳﻚ ﻣﺴﻴﺮ ﺧﻄﻲ‬ ‫ﻭ ﻳﺎ ﻏﻴﺮ ﺧﻄﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺳﺘﻴﺎﺑﻲ ﭘﻴﺪﺍ ﻛﺮﺩ‪.‬‬

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‫ﺑﻬﺮ ﺣﺎﻝ ﺯﻣﺎﻧﻴﻜﻪ ﻣﺠﻤﻮﻋﻪ ﻭﺳﻴﻌﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺎ ﻫﺮ ﺭﻭﺵ ﻣﻤﻜﻦ ﺫﺧﻴﺮﻩ ﻧﻤﺎﺋﻴﻢ‪,‬‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺭﻭﺷﻬﺎﺋﻲ ﺭﺍ ﻧﻴﺰ ﺑﺮﺍﻱ ﺑﺎﺯﻳﺎﺑﻲ ﻭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺁﻧﺎﻥ ﺗﺪﻭﻳﻦ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﻣﺪﻟﻬﺎﻱ‬ ‫ﻗﺪﻳﻤﻲ ﺟﻬﺖ ﺣﺮﮐﺖ ﺍﺯ ﻳﻚ ﺻﻔﺤﻪ )ﻳﻚ ﺣﺮﻳﻢ ﺍﻃﻼﻋﺎﺗﻲ( ﺑﻪ ﺻﻔﺤﻪ ﺩﻳﮕﺮ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺑﺼﻮﺭﺕ ﺧﻄﻲ ﺣﺮﻛﺖ ﻧﻤﻮﺩ‪ ).‬ﺍﺑﺘﺪﺍ ﺻﻔﺤﻪ ﻳﻚ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺻﻔﺤﻪ ﺩﻭ ﻭ …( ﺩﺭ ﻳﻚ‬ ‫ﺍﺑﺮ ﻣﺘﻦ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﻣﻴﺘﻮﺍﻥ ﺍﺯ ﻳﻚ ﻭﺍﮊﻩ ﺑﻪ ﻭﺍﮊﻩ ﺩﻳﮕﺮ ﭘﺮﺵ ﻭ‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪.‬ﻣﺜﻼ" ﺩﺭ ﻳﻚ ﺩﺍﻳﺮﻩ ﺍﻟﻤﻌﺎﺭﻑ ﻛﻪ ﺑﺼﻮﺭﺕ ﺍﺑﺮ ﻣﺘﻨﻲ ﭘﻴﺎﺩﻩ‬ ‫ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﺳﺖ‪ ,‬ﻣﻴﺘﻮﺍﻥ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ " ﻧﻴﻤﺎ ﻳﻮﺷﻴﺞ " ﻣﺸﺎﻫﺪﻩ ﻭ ﺩﺭ ﻫﻤﺎﻥ‬

‫ﻭﺿﻌﻴﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﻧﻴﺰ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ " ﻳﻮﺷﻴﺞ " ﺯﺍﺩﮔﺎﻩ ﻭﻱ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﻣﺸﺎﻫﺪﻩ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ "ﻳﻮﺷﻴﺞ " ﻣﻴﺘﻮﺍﻥ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺳﺘﺎﻥ ﻣﺎﺯﻧﺪﺭﺍﻥ ﻧﻴﺰ ﺩﺭﻳﺎﻓﺖ‬ ‫ﻛﺮﺩ‪ .‬ﺩﺭ ﮔﺬﺷﺘﻪ ﺍﻛﺜﺮ ﺍﻃﻼﻋﺎﺗﻲ ﻛﻪ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺩﺭﺍﺧﺘﻴﺎﺭ ﺍﺳﺘﻔﺎﺩﻩ ﻛﻨﻨﺪﮔﺎﻥ ﻗﺮﺍﺭ ﻣﻲ ﮔﺮﻓﺖ‬

‫ﺑﺼﻮﺭﺕ"ﻣﺘﻦ")‪ (Text‬ﺑﻮﺩ‪ ,‬ﻭﻟﻲ ﺍﻣﺮﻭﺯﻩ ﺑﺎ ﺑﻜﺎﺭﮔﻴﺮﻱ ﺍﻣﻜﺎﻧﺎﺕ ﭼﻨﺪ ﺭﺳﺎﻧﻪ ﺍﻱ‬ ‫)‪ (MultiMedia‬ﻧﻈﻴﺮ ﺻﻮﺕ‪ ,‬ﮔﺮﺍﻓﻴﻚ‪ ,‬ﺍﻧﻴﻤﻴﺸﻦ ﻭ ﺗﺼﻮﻳﺮ ﻣﻴﺘﻮﺍﻥ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺎ ﺍﺷﻜﺎﻝ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺖ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪ .‬ﻣﺜﻼ" ﻣﻴﺘﻮﺍﻥ ﻳﻚ ﺳﺎﻳﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ‬

‫ﻓﻴﻠﻢ ﻫﺎﻱ ﻭﻳﺪﺋﻮﺋﻲ ﺭﺍ ﺍﻳﺠﺎﺩ ﻭ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺎﻳﺖ‪ ،‬ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﻓﻴﻠﻢ ﻣﻮﺭﺩ ﻋﻼﻗﻪ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﻭﺏ ﺑﻌﻨﻮﺍﻥ ﺑﺨﺸﻲ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺤﺴﻮﺏ ﻣﻴﮕﺮﺩﺩ )ﺍﻳﻨﺘﺮﻧﺖ ﻳﻚ ﺷﺒﻜﻪ ﮔﺴﺘﺮﺩﻩ ﺟﻬﺎﻧﻲ‬ ‫ﺍﺯ ﻛﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺑﻬﻢ ﻣﺮﺗﺒﻂ ﻣﻲ ﺑﺎﺷﺪ(‪ .‬ﻭﺏ ﻳﻚ ﺳﻴﺴﺘﻢ ﻣﺪﻳﺮﻳﺖ ﺑﺎﻧﻚ ﺍﻃﻼﻋﺎﺗﻲ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ‪ /‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﻮﺩﻩ ﻛﻪ ﺍﺯ ﻳﻚ ﺳﺎﺧﺘﺎﺭ ﻭ ﻣﻌﻤﺎﺭﻱ ﻣﺸﺨﺺ ﺟﻬﺖ ﺑﺎﺯﻳﺎﺑﻲ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻛﻨﺪ‪ .‬ﺗﻤﺎﻣﻲ ﻣﺮﻭﺭﮔﺮﻫﺎ )‪ (Browser‬ﺑﺎ ﺁﮔﺎﻫﻲ ﺍﺯ ﺍﻳﻦ ﻣﻌﻤﺎﺭﻱ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻣﺮﻭﺭﮔﺮﻫﺎ‪ ,‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﺋﻲ ﻫﺴﺘﻨﺪ ﻛﻪ ﭘﺲ‬ ‫ﺍﺯ ﻧﺼﺐ ﻭ ﺑﻬﺮﻩ ﺑﺮﺩﺍﺭﻱ ﺍﺯ ﺁﻧﺎﻥ ﻣﻴﺘﻮﺍﻥ ﺍﺯ ﻳﻚ ﺳﺎﻳﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﺳﺎﻳﺖ ﺩﮔﺮ ﺣﺮﻛﺖ‬

‫ﻧﻤﻮﺩ‪.‬ﺍﻭﻟﻴﻦ ﺑﺎﺭ ﻳﻚ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺲ ﺍﻧﮕﻠﻴﺴﻲ ﺑﻨﺎﻡ " ﺑﺮﻧﺮﺯ ﻟﻲ " ﺍﻳﺪﻩ ﺗﺮﻛﻴﺐ ﺍﺑﺮ ﺭﺳﺎﻧﻪ ﻫﺎ ﺭﺍ‬ ‫ﻣﻨﺎﺑﻊ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻄﺮﺡ ﻧﻤﻮﺩ‪ .‬ﻗﺒﻞ ﺍﺯ ﻭﺏ ﻣﻨﺎﺑﻊ ﻭ ﺍﻗﻼﻡ ﺍﻃﻼﻋﺎﺗﻲ ﮔﻮﻧﺎﮔﻮﻧﻲ ﺩﺭ‬

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‫ﺍﻳﻨﺘﺮﻧﺖ ﻭﺟﻮﺩ ﺩﺍﺷﺖ ﻭﻟﻲ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺁﻧﻬﺎ ﺑﺴﺎﺩﮔﻲ ﻣﻴﺴﺮ ﻧﺒﻮﺩ‪ .‬ﺩﺭ ﺳﺎﻝ ‪"١٩٨٩‬ﺯﻣﺎﻧﻴﻜﻪ"‬ ‫ﺑﺮﻧﺮﺯﻟﻲ" ﺑﺮ ﺭﻭﻱ ﻳﻚ ﭘﺮﻭﮊﻩ ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻛﺮﺩ‪ ,‬ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ ﻛﻪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ‬ ‫ﻧﻴﺎﺯ ﺟﻬﺖ ﻛﺎﺭ ﻫﻤﺰﻣﺎﻥ ﺑﺮ ﺭﻭﻱ ﭘﺮﻭﮊﻩ ﺑﺮﺍﻱ ﺍﻓﺮﺍﺩ‪ ,‬ﻋﻤﻠﻴﺎﺗﻲ ﻃﺎﻗﺖ ﻓﺮﺳﺎ ﻭ ﻣﺸﻜﻞ ﺍﺳﺖ‪.‬ﻭﻱ‬ ‫ﺑﺎ ﺑﻬﺮﻩ ﮔﻴﺮﻱ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﺍﺑﺮ ﻣﺘﻦ ﻫﺎ‪ ,‬ﺷﺒﻜﻪ ﺍﻱ ﺍﺯ ﻣﺴﺘﻨﺪﺍﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺍﻓﺮﺍﺩ ﺟﻬﺖ ﻓﻌﺎﻟﻴﺖ‬

‫ﺩﺭ ﭘﺮﻭﮊﻩ ﻫﺎﻱ ﮔﻮﻧﺎﮔﻮﻥ ﺭﺍ ﻓﺮﺍﻫﻢ ﺁﻭﺭﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺍﺭﺗﺒﺎﻃﺎﺕ ﻣﺘﻌﺪﺩﻱ ﺑﻪ ﺻﻔﺤﺎﺕ‬ ‫ﻣﺴﺘﻨﺪﺍﺕ‪ ,‬ﺍﻳﺠﺎﺩ ﻭ ﺗﻤﺎﻣﻲ ﺟﺰﺋﻴﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺍﺯ ﺩﻳﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻛﻨﻨﺪﻩ ﻣﺨﻔﻲ ﻣﻲ ﻣﺎﻧﺪ‪.‬‬

‫ﻣﺴﺘﻨﺪﺍﺕ ﻭﺏ ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﻳﻚ ﻗﺎﻟﺐ ﺧﺎﺹ ﻧﻮﺷﺘﻪ ﺷﻮﻧﺪ‪ ,‬ﺑﮕﻮﻧﻪ ﺍﻱ ﻛﻪ ﺍﺑﺮ ﻣﺘﻦ ﻫﺎ‬ ‫ﺑﺘﻮﺍﻧﻨﺪ ﺑﺎ ﻳﻜﺪﻳﮕﺮ ﻛﺎﺭ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻳﻦ ﻗﺎﻟﺐ ﺧﺎﺹ ‪Hyper Text Markup HTML‬‬ ‫)‪ ( Language‬ﻧﺎﻣﻴﺪﻩ ﺷﺪ‪.‬‬

‫ﺍﻳﻦ ﺯﺑﺎﻥ ﺑﻌﻨﻮﺍﻥ ﺯﻳﺮ ﻣﺠﻤﻮﻋﻪ ﺯﺑﺎﻥ )‪Standard Generalized Markup ) SGML‬‬

‫‪ ( Language‬ﻣﺤﺴﻮﺏ ﻣﻴﮕﺮﺩﺩ‪ SGML.‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻱ ﺟﻬﺖ ﺗﻌﺮﻳﻒ ﻓﻮﺭﻣﺖ ﺩﺭ ﻣﺴﺘﻨﺪﺍﺕ‬ ‫ﻣﺘﻨﻲ ﺍﺳﺖ‪.‬ﺍﺯ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻓﻮﻕ ﺩﺭ ﮔﺬﺷﺘﻪ ﺍﻏﻠﺐ ﺟﻬﺖ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﻧﺸﺮ ﺭﻭﻣﻴﺰﻱ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﺪ‪ ".‬ﺑﺮﻧﺮﺯﻟﻲ " ﺍﺯ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﺍﺑﺮﻣﺘﻦ ﻫﺎ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺍﻭﻟﻴﻦ ﻣﺴﺘﻨﺪﺍﺕ ﺩﺭ ﻭﺏ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬ﺟﻬﺖ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻭﻟﻴﻦ ﺳﺎﻳﺖ ﻫﺎﻱ ﻭﺏ ﺍﺯ ﻳﻚ ﻣﺮﻭﺭﮔﺮ ﺧﻄﻲ ﻭﺏ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﺷﺪ‪ .‬ﺍﻳﻦ ﻣﺮﻭﺭﮔﺮ ﻣﺤﺪﻭﺩ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺻﺮﻓﺎ" ﻳﻚ ﺧﻂ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﻜﻲ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻨﺎﻡ ‪ TelNet‬ﺟﻬﺖ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺩﻭ ﺳﺎﻳﺖ‬ ‫ﺍﻭﻟﻴﻪ ﻭﺏ ﺑﺎ ﻧﺎﻣﻬﺎﻱ ‪ Infacern.ch‬ﻭ ﻳﺎ ‪ Nxo01.cern.ch‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻴﮕﺮﺩﻳﺪ‪ .‬ﺍﻳﻦ‬ ‫ﻣﺮﻭﺭﮔﺮ ﺩﺍﺭﺍﻱ ﺩﺳﺘﻮﺭﺍﺗﻲ ﻧﻈﻴﺮ‪ Start a Search :‬ﻭ ‪ Follow a Link‬ﺑﻮﺩ‪ .‬ﺍﻛﺜﺮ‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﺎﻳﺖ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ‪ ،‬ﺍﺯ ﺍﻣﻜﺎﻧﺎﺕ ﺍﺑﺮ ﻣﺘﻦ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﻛﺮﺩﻧﺪ ﻭ ﻫﻤﻴﻦ‬

‫ﺍﻣﺮ ﺑﺎﻋﺚ ﻋﺪﻡ ﺑﻜﺎﺭﮔﻴﺮﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﺍﺑﺮﻣﺘﻦ ﻫﺎ ﺩﺭ ﻣﺴﺘﻨﺪﺍﺕ ﺍﻭﻟﻴﻪ ﻭ ﻋﺪﻡ ﺭﺷﺪ ﻣﻨﺎﺳﺐ‬

‫ﻭﺏ ﮔﺮﺩﻳﺪ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﻋﺎﻣﻞ ﺭﺷﺪ ﻭ ﻓﺮﺍﮔﻴﺮ ﺷﺪﻥ ﻭﺏ ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ‪ ,‬ﻋﺮﺿﻪ ﻣﺮﻭﺭﮔﺮ "‬ ‫ﻣﻮﺯﺍﺋﻴﻚ " ﺑﻪ ﺑﺎﺯﺍﺭ ﺑﻮﺩ‪.‬‬

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‫ﻣﻮﺯﺍﺋﻴﻚ ) ﺗﻮﻟﺪ ﻧﺴﻞ ﺟﺪﻳﺪﻱ ﺍﺯ ﻣﺮﻭﺭﮔﺮﻫﺎ (‬

‫" ﻣﺎﺭﻙ ﺁﻧﺪﺭﺳﻮﻥ " ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٣‬ﭘﺮﻭﮊﻩ ﺗﻮﻟﻴﺪ ﻭ ﻃﺮﺍﺣﻲ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﻮﺯﺍﺋﻴﻚ ﺭﺍ‬ ‫ﻫﺪﺍﻳﺖ ﻧﻤﻮﺩ‪ .‬ﻫﺪﻑ ﺍﺯ ﻃﺮﺍﺣﻲ ﻣﻮﺯﺍﺋﻴﻚ‪ ،‬ﺍﺭﺍﺋﻪ ﺭﺍﻫﻜﺎﺭﻱ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﺍﻓﺮﺍﺩﻱ ﺑﻮﺩ ﻛﻪ ﺑﺮ‬ ‫ﺭﻭﻱ ﭘﺮﻭﮊﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻓﻌﺎﻟﻴﺖ ﺩﺍﺷﺘﻪ ﻭ ﻣﻠﺰﻡ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﻣﺸﺘﺮﻙ‬ ‫ﺑﻮﺩﻧﺪ‪.‬ﺩﺭ ﺍﺑﺘﺪﺍ " ﺁﻧﺪﺭﺳﻮﻥ " ﺍﺯ ﻭﺟﻮﺩ ﻭﺏ ﻫﻴﭽﮕﻮﻧﻪ ﺍﻃﻼﻋﻲ ﻧﺪﺍﺷﺖ ﻭ ﺟﻬﺖ ﺍﺭﺍﺋﻪ ﺭﺍﻩ ﺣﻞ‬ ‫ﻣﻨﺎﺳﺐ‪ ،‬ﺗﺤﻘﻴﻘﺎﺕ ﮔﺴﺘﺮﺩﻩ ﺍﻱ ﺗﻮﺳﻂ ﻭﻱ ﺍﻧﺠﺎﻡ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ ﻭﻱ ﻭﺏ ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﻳﻚ ﺭﺍ ﻩ‬ ‫ﺣﻞ ﻣﻨﺎﺳﺐ ﻛﺸﻒ ﻧﻤﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺷﻨﺎﺧﺖ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻭﺏ ﺗﻮﺳﻂ " ﺁﻧﺪﺭﺳﻮﻥ "‪،‬‬

‫ﺍﻳﺪﻩ ﻃﺮﺍﺣﻲ ﻣﻮﺯﺍﺋﻴﻚ ﺑﻌﻨﻮﺍﻥ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ﺗﻮﺳﻂ ﻭﻱ ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪.‬ﺩﺭ ﺁﻭﺭﻳﻞ ‪ ١٩٩٣‬ﺍﻭﻟﻴﻦ‬ ‫ﻧﺴﺨﻪ ﻣﻮﺯﺍﺋﻴﻚ ) ‪ ( Ver 1.0‬ﺑﺮﺍﻱ ﺳﻴﺴﺘﻢ ‪ Windows‬ﺍﺭﺍﺋﻪ ﮔﺮﺩﻳﺪ‪.‬ﺍﻳﻦ ﺑﺮﻧﺎﻣﻪ ﺑﺴﺮﻋﺖ‬

‫ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ ﻣﻄﺮﺡ ﻭ ﺑﺎﻋﺚ ﺍﻋﺘﺒﺎﺭ ﻭ ﺷﻬﺮﺕ ﻓﺮﺍﻭﺍﻥ ﻭﺏ ﮔﺮﺩﻳﺪ‪ .‬ﺑﺪﻟﻴﻞ ﺍﻋﺘﺒﺎﺭ ﻭ ﻋﻤﻮﻣﻴﺖ‬

‫ﻳﺎﻓﺘﻦ ﻣﻮﺯﺍﺋﻴﻚ‪) NCSA ،‬ﻣﺮﻛﺰ ﻣﻠﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﻣﺤﺎﺳﺒﺎﺗﻲ( ﻧﺴﺨﻪ ﻫﺎﻱ ﻭﻳﻨﺪﻭﺯ ﻭ‬ ‫ﺍﭘﻞ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺭﺍ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻧﻤﻮﺩ‪ .‬ﻣﺮﻛﺰ ﻓﻮﻕ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﻌﺮﻳﻒ ﺧﺎﺹ ﺣﻮﺯﻩ ﻓﻌﺎﻟﻴﺖ‬

‫ﺧﻮﺩ ﻣﺠﺒﻮﺭ ﺑﻪ ﻓﺮﻭﺵ ﺍﻣﺘﻴﺎﺯ " ﻣﻮﺯﺍﺋﻴﻚ " ﺑﻪ ﭼﻨﺪﻳﻦ ﺷﺮﻛﺖ ﺍﺯ ﺟﻤﻠﻪ‪Mosaic :‬‬

‫‪ Communication‬ﻭ ‪ Quarterdeck spry‬ﺷﺪ‪.‬ﺩﺭ ﺳﺎﻝ ‪ " ١٩٩٤‬ﻣﺎﺭﻙ ﺁﻧﺪﺭﺳﻮﻥ‬ ‫"‪ NCSA‬ﺭﺍ ﺗﺮﻙ ﻭ ﺑﻪ ﻳﻚ ﺷﺮﻛﺖ ﺟﺪﻳﺪﺍﻟﺘﺎﺳﻴﺲ ﺑﻨﺎﻡ " ﻧﺖ ﺍﺳﻜﻴﭗ" )‪( NetScape‬‬

‫ﭘﻴﻮﺳﺖ‪ .‬ﭘﺲ ﺍﺯ ﭘﻴﻮﺳﺘﻦ ﻭﻱ ﺑﻪ ﻧﺖ ﺍﺳﻜﻴﭗ‪ ,‬ﻣﺮﻭﺭﮔﺮ ﺟﺪﻳﺪﻱ ﺗﻮﺳﻂ ﺍﻳﻦ ﺷﺮﻛﺖ ﻃﺮﺍﺣﻲ‬

‫ﻭﺑﺎ ﻧﺎﻡ ‪ Netscape Navigator‬ﺑﻪ ﺑﺎﺯﺍﺭ ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺍﻳﻦ ﻣﺮﻭﺭﮔﺮ ﺍﻧﻘﻼﺑﻲ ﺩﺭ ﺯﻣﻴﻨﻪ‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎ ﺭﺍ ﺑﻮﺟﻮﺩ ﺁﻭﺭﺩ ﻭ ﭘﺲ ﺍﺯ ﻣﺪﺕ ﺯﻣﺎﻥ ﻛﻮﺗﺎﻫﻲ ﺑﻌﻨﻮﺍﻥ ﭘﺮﻓﺮﻭﺷﺘﺮﻳﻦ ﻣﺮﻭﺭﮔﺮ ﺩﺭ‬ ‫ﺳﻄﺢ ﺟﻬﺎﻥ ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪.‬‬ ‫ﺭﺷﺪ ﻭ ﺗﻮﺳﻌﻪ ﻭﺏ‬ ‫ﻭﺏ ﺑﺎ ﻳﻚ ﺳﺮﻋﺖ ﺣﻴﺮﺕ ﺍﻧﮕﻴﺰ ﺩﺭ ﺣﺎﻝ ﺭﺷﺪ ﻭ ﺗﻮﺳﻌﻪ ﺍﺳﺖ‪.‬ﺍﻣﺮﻭﺯﻩ ﺩﺭ ﺍﻛﺜﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ‬ ‫ﺗﻠﻮﻳﺰﻳﻮﻧﻲ ﻭ ﭘﺨﺶ ﺁﮔﻬﻲ ﻫﺎﻱ ﺗﺠﺎﺭﻱ ﻛﻤﺘﺮﻳﻦ ﺁﮔﻬﻲ ﺭﺍ ﻣﻴﺘﻮﺍﻥ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ ﻛﻪ ﻣﺘﻘﺎﺿﻴﺎﻥ‬

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‫ﺭﺍ ﺟﻬﺖ ﻛﺴﺐ ﺍﻃﻼﻋﺎﺕ ﺑﻴﺸﺘﺮ ﺑﻪ ﻳﻚ ﻭﺏ ﺳﺎﻳﺖ ﻫﺪﺍﻳﺖ ﻧﻨﻤﺎﻳﺪ‪ .‬ﻳﻚ ﻭﺏ ﺳﺎﻳﺖ‪,‬‬

‫ﺳﻴﺴﺘﻤﻲ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ ﻛﻪ ﺷﺎﻣﻞ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ )‪ (Web Server‬ﺍﺳﺖ‪.‬‬ ‫ﺍﻳﻦ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺖ ﺍﺳﺖ ﻛﻪ ﺍﻣﻜﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ‬ ‫ﺭﺍ ﺑﻪ ﻣﺴﺘﻨﺪﺍﺕ ﻣﻮﺟﻮﺩ ﻓﺮﺍﻫﻢ ﻣﻲ ﻛﻨﺪ‪.‬ﺩﺭ ﮔﺬﺷﺘﻪ ﺑﺪﻟﻴﻞ ﺗﺮﺍﻓﻴﻚ ﺑﺎﻻﻱ ﻣﺼﺎﺭﻑ ﺳﻴﺎﺳﻲ ﺍﺯ‬

‫ﺍﻳﻨﺘﺮﻧﺖ‪ ,‬ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﺩﺭ ﺑﻌﺪ ﺗﺠﺎﺭﻱ ﻭ ﺍﻗﺘﺼﺎﺩﻱ ﻓﺮﺍﻫﻢ ﻧﺒﻮﺩ‪.‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٩١‬ﺑﺎ‬ ‫ﭘﻴﺪﺍﻳﺶ ﺍﻳﺪﻩ ﺗﺒﺎﺩﻝ ﺍﻗﺘﺼﺎﺩﻱ ﺍﻳﻨﺘﺮﻧﺖ ‪(Commerical Internet Exchange) CIX‬‬ ‫ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﺗﻐﻴﻴﺮ ﻛﺮﺩ‪ CIX .‬ﺗﻮﺳﻂ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﮔﺎﻥ ﺳﺮﻭﻳﺴﻬﺎﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺗﺤﺖ‬ ‫‪ AlterNet,CERfent,PSInet‬ﺍﺭﺍﺋﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺍﻳﻦ ﺳﻴﺴﺘﻢ ﺑﺎ ﻣﻮﻓﻘﻴﺖ ﻭ ﺍﺳﺘﻘﺒﺎﻝ‬ ‫ﭼﺸﻤﮕﻴﺮﻱ ﻣﻮﺍﺟﻪ ﮔﺮﺩﻳﺪ‪.‬ﺍﻣﺮﻭﺯﻩ ﺍﻏﻠﺐ ﺗﻮﻟﻴﺪ ﻛﻨﻨﺪﮔﺎﻥ ﻛﺎﻻ ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﻛﺎﻻﻱ ﺧﻮﺩ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﻭﺏ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺳﺎﻳﺖ ﻫﺎﻱ ﺷﻨﺎﺧﺘﻪ ﺷﺪﻩ ﺍﻱ ﺍﺭﺍﺋﻪ‬

‫ﻣﻴﺪﻫﻨﺪ‪.‬ﻣﺘﻘﺎﺿﻴﺎﻥ ﻛﺎﻻ ﺩﺭ ﻫﺮ ﻧﻘﻄﻪ ﺍﺯ ﺟﻬﺎﻥ ﺑﺎ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺎﻳﺖ ﻣﺮﺑﻮﻁ ﺑﻪ ﺁﻥ ﺷﺮﻛﺖ ﻭ ﻳﺎ‬ ‫ﺷﺮﻛﺖ ﻫﺎﻱ ﻣﺸﺎﺑﻪ ﻣﻴﺘﻮﺍﻧﻨﺪ ﺁﮔﺎﻫﺎﻧﻪ ﻧﺴﺒﺖ ﺑﻪ ﺍﻧﺘﺨﺎﺏ ﻛﺎﻻﻱ ﻣﻮﺭﺩ ﻋﻼﻗﻪ ﺧﻮﺩ ﺍﻗﺪﺍﻡ ﻭ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﻭﺏ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪.‬ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ ﺷﺮﻛﺖ ﻫﺎ ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ‬ ‫ﺑﺎﻻﺧﺺ ﺷﺮﻛﺖ ﻫﺎﻱ ﻛﺎﻣﭙﻴﻮﺗﺮﻱ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻓﻨﻲ ﻭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺧﻮﺩ ﺭﺍ ﺑﻪ ﻣﺸﺘﺮﻳﺎﻥ ﺍﺯ‬

‫ﻃﺮﻳﻖ ﻭﺏ ﺍﻧﺠﺎﻡ ﻣﻴﺪﻫﻨﺪ‪ .‬ﻣﺜﻼ" ﺑﺎ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺎﻳﺖ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ﻋﻼﻭﻩ ﺑﺮ ﺍﻣﻜﺎﻥ ﺧﺮﻳﺪ‬ ‫ﻣﺤﺼﻮﻝ ﻣﻮﺭﺩ ﻧﻈﺮﺧﻮﺩ‪ ،‬ﺩﺭﺻﻮﺭﺗﻴﻜﻪ ﺩﺭ ﺯﻣﻴﻨﻪ ﺑﻜﺎﺭﮔﻴﺮﻱ ﻳﻜﻲ ﺍﺯ ﻣﺤﺼﻮﻻﺕ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‬

‫ﺁﻥ ﺷﺮﻛﺖ ﺩﺍﺭﺍﻱ ﺳﻮﺍﻻﺕ ﻭ ﺍﺑﻬﺎﻣﺎﺗﻲ ﺑﺎﺷﻴﻢ‪ ,‬ﺑﺎ ﺍﺳﺘﻘﺮﺍﺭ ﺩﺭ ﺑﺨﺶ ﻓﻨﻲ ﻭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﻣﻴﺘﻮﺍﻥ‬

‫ﭘﺎﺳﺦ ﻭ ﺭﻫﻨﻤﻮﺩﻫﺎﻱ ﻻﺯﻡ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻛﺮﺩ‪.‬ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ ﺷﺮﻛﺖ ﻫﺎ ﺑﺎﻻﺧﺺ ﺷﺮﻛﺖ ﻫﺎﻱ‬ ‫ﺍﻧﺘﺸﺎﺭﺍﺗﻲ ﻭ ﭼﺎﭖ ﻣﺠﻼﺕ‪ ،‬ﺭﻭﺯﻧﺎﻣﻪ ﻫﺎ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺧﻮﺩ ﺭﺍ )ﺭﻭﺯﻧﺎﻣﻪ ﻫﺎ ﻭ ﻣﺠﻼﺕ( ﺑﺮ ﺭﻭﻱ‬ ‫ﺷﺒﻜﻪ ﻗﺮﺍﺭﺩﺍﺩﻩ ﻭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﻳﺎ ﺧﺮﻳﺪ ﺭﺍ ﺑﺮﺍﻱ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺗﻤﺎﻣﻲ‬

‫ﻣﺘﻘﺎﺿﻴﺎﻥ ﺟﻬﺖ ﺧﺮﻳﺪ ﮐﺎﻻﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺧﻮﺩ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ‪ ,‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻳﻜﻲ ﺍﺯ‬ ‫ﺍﻧﻮﺍﻉ ﻣﺘﺪﺍﻭﻝ ﻛﺎﺭﺗﻬﺎﻱ ﺍﻋﺘﺒﺎﺭﻱ ﻧﻈﻴﺮ ‪ Credit Card :‬ﻭ ﻳﺎ ‪ MasterCard‬ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﺍﻧﺘﺨﺎﺏ ﻛﺎﻻ ﺍﺯ ﻃﺮﻳﻖ ﻣﺘﻘﺎﺿﻲ ﻭ ﺗﻌﻴﻴﻦ ﻧﺤﻮﻩ ﭘﺮﺩﺍﺧﺖ ﺷﻤﺎﺭﻩ ﻣﺮﺑﻮﻁ ﺑﻪ ﻛﺎﺭﺕ‬

‫ﺍﻋﺘﺒﺎﺭﻱ‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺳﻴﺴﺘﻢ ﺩﺍﺩﻩ ﺷﻮﺩ‪ .‬ﺛﺒﺖ ﻭ ﺩﺭﺝ ﺷﻤﺎﺭﻩ ﻛﺎﺭﺗﻬﺎﻱ ﺍﻋﺘﺒﺎﺭﻱ ﻳﻜﻲ ﺍﺯ‬

‫ﻣﺴﺎﺋﻞ ﻣﻬﻢ ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﻣﻨﻴﺖ ﺩﺭ ﺗﺠﺎﺭﺕ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ‪ .‬ﻫﺮ ﻓﺮﺩ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻳﻦ‬ ‫ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ﻛﻪ ﺍﺯ ﺷﻤﺎﺭﻩ ﻛﺎﺭﺕ ﺍﻋﺘﺒﺎﺭﻱ ﻭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻏﻴﺮ ﻗﺎﻧﻮﻧﻲ ﺑﻌﻤﻞ ﻧﻤﻲ ﺁﻳﺪ‪.‬‬

‫ﺑﻪ ﻫﻤﻴﻦ ﺩﻟﻴﻞ ﻭﺏ ﻣﺠﻬﺰ ﺑﻪ ﻳﻚ ﺳﻴﺴﺘﻢ ﺭﻣﺰﮔﺬﺍﺭﻱ ﻣﻄﻤﺌﻦ ﺟﻬﺖ ﻛﺎﺭﺕ ﻫﺎﻱ ﺍﻋﺘﺒﺎﺭﻱ‬ ‫ﺍﺳﺖ‪.‬‬ ‫ﺍﺻﻮﻝ ﻭ ﺗﻌﺎﺭﻳﻒ ﺍﻭﻟﻴﻪ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻭﺏ‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻭﺏ ﺩﺭ ﺣﺮﻳﻢ ﻫﺎﻱ ﺍﻃﻼﻋــــــﺎﺗﻲ ﺑﺎ ﻧﺎﻡ " ﺻﻔﺤﺎﺕ ﻭﺏ "‬

‫ﺫﺧﻴـــﺮﻩ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪ .‬ﺍﻧﺪﺍﺯﻩ ﻭﻧﻮﻉ ﻣﺤﺘﻮﻳﺎﺕ ﺍﻳﻦ ﻧﻮﻉ ﺻﻔﺤﺎﺕ ﮐﺎﻣﻼ" ﻣﺘﻐﻴﺮ ﺑﻮﺩﻩ ﻭ‬

‫ﻧﻤﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﺑﺎ ﻳﮏ ﺻﻔﺤﻪ ﮐﺘﺎﺏ ﻣﻘﺎﻳﺴﻪ ﮐﺮﺩ ﮔﺮﭼﻪ‬ ‫ﺷﺒﺎﻫﺖ ﻫﺎﻱ ﺍﻧﺪﮐﻲ ﻧﻴﺰ ﺑﻴﻦ ﺁﻧﻬﺎ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪.‬‬ ‫ﻣﺤﺘﻮﻳﺎﺕ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﻣﻲ ﺗﻮﺍﻧﺪ‪ :‬ﻣﺘﻦ ﺭﺍﻓﻴﮏ ﺻﺪﺍ ﺗﺼﻮﻳﺮ ﺍﻧﻴﻤﻴﺸﻦ ﻭ ‪ ...‬ﺑﺎﺷﺪ‪.‬‬

‫ﮔﺴﺘﺮﺩﮔﻲ ﻭ ﺗﻨﻮﻉ ﻧﻮﻉ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ ﻗﺮﺍﺭ ﺩﺍﺩ ﻳﮑﻲ ﺍﺯ‬

‫ﻣﻬﻤﺘﺮﻳﻦ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻗﺎﺑﻞ ﺗﻮﺟﻪ ﻭﺏ ﺍﺯ ﺩﻳﺪﮔﺎﻩ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﮔﺎﻥ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻳﮑﻄﺮﻑ‬ ‫ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻑ ﺩﻳﮕﺮ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﺯ ﻟﺤﺎﻅ ﻓﻴﺰﻳﮑﻲ ﻓﺎﻳﻞ ﻫﺎﻱ ﻫﺴﺘﻨﺪ ﮐﻪ ﺗﻮﺳﻂ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺑﻮﺟﻮﺩ‬ ‫ﺁﻣﺪﻩ ﻭ ﺩﺍﺭﺍﻱ ﺍﻧﺸﻌﺎﺏ "‪ "htm‬ﻭ ﻳﺎ "‪ ""html‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺍﻳﻦ ﻧﻮﻉ ﺻﻔﺤﺎﺕ‬

‫ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺗﻤﺎﻡ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﺋﻲ ﮐﻪ ﺑﻨﻮﻋﻲ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﻳﮏ ﻓﺎﻳﻞ‬ ‫ﻫﺴﺘﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ Notepad ).‬ﻧﻤﻮﻧﻪ ﺍﻱ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎ ﺍﺳﺖ(‪ .‬ﺍﻣﺮﻭﺯﻩ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﻫﺎﻱ ﮐﺎﻣﻼ" ﺣﺮﻓﻪ ﺍﻱ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻭ ﻣﺪﻳﺮﻳﺖ ﺻﻔﺤﺎﺕ ﻭﺏ ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﻫﺎﻱ‬

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‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ ‪ ...,FrontPage,Hotmetal .‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬ﭘﺲ ﺍﺯ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﺩﺭ ﺻﻮﺭﺕ ﻧﻴﺎﺯ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﻋﻤﻮﻡ )ﺩﺍﺧﻠﻲ ‪،‬‬ ‫ﺧﺎﺭﺟﻲ( ﻣﻲ ﺑﺎﻳﺴﺖ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﺎﻳﺖ ﺫﺧﻴﺮﻩ ﻧﻤﻮﺩ‪ .‬ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﻣﺠﻤﻮﻋﻪ‬ ‫ﺍﻱ ﺍﺯ ﺻﻔﺤﺎﺕ ﻭﺏ ﺭﺍ ﺷﺎﻣﻞ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﮔﺎﻥ ﺍﻃﻼﻋﺎﺕ ﭘﺲ ﺍﺯ ﺁﻣﺎﺩﻩ ﺳﺎﺯﻱ ﺻﻔﺤﺎﺕ ﻭﺏ ﻭ ﺍﺳﺘﻘﺮﺍﺭ ﺁﻧﻬﺎ ﺑﺮ ﺭﻭﻱ ﻳﮏ‬ ‫ﻭﺏ ﺳﺎﻳﺖ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ ﺭﺍ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﺋﻲ ﻣﻮﺳﻮﻡ ﺑﻪ " ﻣﺮﻭﺭﮔﺮ" ﻗﺎﺩﺭ ﺑﻪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ‬ ‫ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﻭ ﺩﺭﺧﻮﺍﺳﺖ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺧﻮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺗﻤﺎﻡ ﺻﻔﺤﺎﺕ ﻭﺏ ﺩﺍﺭﺍﻱ ﻣﺠﻤﻮﻋﻪ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﺋﻲ ﻫﺴﺘﻨﺪ ﮐﻪ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺭﺍﻳﺞ ﺗﺮﻳﻦ ﻣﺠﻤﻮﻋﻪ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻧﻤﺎﻳﺶ ﺩﺭ‬ ‫ﺻﻔﺤﺎﺕ ﻭﺏ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻫﻤﺎﻧﻄﻮﺭ ﮐﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻣﺠﻤﻮﻋﻪ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻧﻤﺎﻳﺶ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ‬ ‫ﺍﺯ ﺷﺒﻪ ﺯﺑﺎﻥ ‪ Html‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬ﺷﺒﻪ ﺯﺑﺎﻥ ﻓﻮﻕ‪ ،‬ﺭﺍ ﻧﻤﻲ ﺗﻮﺍﻥ ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺯﺑﺎﻥ ﺑﺮﻧﺎﻣﻪ‬

‫ﻧﻮﻳﺴﻲ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺖ ﭼﺮﺍﮐﻪ ﻋﻤﻼ" ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﭘﺮﺩﺍﺯﺵ ﺭﺍ ﺷﺎﻣﻞ ﻧﺸﺪﻩ ﻭ ﺻﺮﻓﺎ" ﺩﺭ‬ ‫ﺣﺪ ﺗﻮﺻﻴﻒ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ ﻣﺤﺘﻮﻳﺎﺕ ﺍﺳﺖ‪ Html .‬ﺩﺍﺭﺍﻱ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮐﺪﻫﺎﻱ ﺗﻮﺻﻴﻔﻲ‬ ‫ﺑﺮﺍﻱ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻣﺮﻭﺭﮔﺮﻫﺎ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﺯﺑﺎﻥ ﺩﺍﺭﺍﻱ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺗﮓ ﻫﺎ ﺍﺳﺖ‬ ‫ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﻱ ﻣﻌﺎﻧﻲ ﻭ ﻋﻤﻠﮑﺮﺩ ﺍﺯ ﻗﺒﻞ ﻣﺸﺨﺺ ﺷﺪﻩ ﻫﺴﺘﻨﺪ‪ .‬ﻣﺜﻼ" ﺗﮓ ‪ :‬ﺑﺮﺍﻱ‬ ‫ﭘﺮﺭﻧﮓ ﻧﻤﻮﺩﻥ ﻣﺘﻦ ﻣﻮﺭﺩ ﻧﻈﺮ ﻭ ﻳﺎ ﺗﮓ >‪
‫"‪ "Html‬ﻭ ﻳﺎ "‪ "Htm‬ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺣﻘﻴﻘﺖ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﺳﻴﺎﺳﺖ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﻧﺤﻮﻩ‬ ‫ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺭﺍ ﻣﺸﺨﺺ ﻭ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﭘﺲ ﺍﺯ ﺗﻔﺴﻴﺮ‬

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‫ﺗﮓ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭﺍﮐﻨﺶ ﻫﺎﻱ ﺍﺯ ﻗﺒﻞ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺭﺍ ﺍﺯ ﺧﻮﺩ ﻧﺸﺎﻥ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬ ‫ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻲ ﺗﻮﺍﻥ ‪ Html‬ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﺯﺑﺎﻧﻲ ﺑﺮﺍﻱ ﺗﺒﻴﻦ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﺗﻌﺮﻳﻒ ﮐﺮﺩ‪.‬‬ ‫ﻣﺜﺎﻝ ‪ :‬ﻳﮏ ﻧﻤﻮﻧﻪ ﻓﺎﻳﻞ ‪HTML‬‬ ‫>‪‪‪
‫ﻋﻨﻮﺍﻥ‬

‫ﺻﻔﺤﻪ>‪
‫>‪‪‬

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‫‪......‬‬

‫>‪‪
‫‪ html‬ﺩﺍﺭﺍﻱ ﻧﺴﺨﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺯ ﺑﺪﻭ ﭘﻴﺪﺍﻳﺶ ﺗﺎﮐﻨﻮﻥ ﺑﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ‬

‫ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﻣﻲ ﺑﺎﻳﺴﺖ‪ ،‬ﻧﻮﻉ ﻧﺴﺨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ‪ Html‬ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﻮﺩ‪ .‬ﺍﻳﻦ‬ ‫ﻋﻤﻠﻴﺎﺕ ﺗﻮﺳﻂ ‪ DOCTYPE‬ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﻧﺴﺨﻪ ﻫﺎﻱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ‬

‫ﻣﺠﻤﻮﻋﻪ ﺗﮓ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺍﻧﻮﺍﻉ ﺍﻳﻦ ﻧﺴﺨﻪ ﻫﺎ ﻭ ﻧﺤﻮﻩ‬ ‫ﺗﻌﺮﻳﻒ ﮐﺮﺩﻥ ﻭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻧﻮﻉ ﻧﺴﺨﻪ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﺷﺎﺭﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫‪ HTML 2.0‬ﻧﺴﺨﻪ ﻓﻮﻕ ﺑﻌﻨﻮﺍﻥ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﻭﻟﻴﻪ )‪ (RFC 1866‬ﻣﻌﺮﻓﻲ ﮔﺮﺩﻳﺪ‪.‬‬ ‫‪"‪Strict//EN‬‬ ‫>"‪"‪
‫‪ Html 4.0‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻣﻌﺮﻓﻲ ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﻨﺴﺮﺳﻴﻮﻡ ﻭﺏ ﮐﻪ ﺩﺍﺭﺍﻱ ﺳﻪ ﮔﺮﺍﻳﺶ ﻣﺘﻔﺎﻭﺕ‬ ‫ﺍﺳﺖ‪:‬‬

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‫ ‪ . Strict HTML 4.0‬ﺍﻳﻦ ﻧﺴﺨﻪ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﻳﻢ ﻭ ﺍﻏﻠﺐ ﻭﻳﮋﮔﻲ ﻫﺎﺋﻲ ﻧﻈﻴﺮ‬‫" ﺗﺮﺍﺯ ﺑﻨﺪﻱ " ﺭﺍ ﺷﺎﻣﻞ ﻧﻤﻲ ﺷﻮﺩ‪.‬‬ ‫"‪"‪"http://www.w3.org/TR/REC-html40/strict.dtd‬‬ ‫ ‪ Transitional HTML 4.0‬ﺍﻣﮑﺎﻧﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﻧﻤﺎﻳﺶ ﻧﻈﻴﺮ " ﺗﺮﺍﺯﺑﻨﺪﻱ " ﺭﺍ ﺩﺍﺭﺍ‬‫ﺑﻮﺩﻩ ﻭﻟﻲ ﻫﻤﭽﻨﺎﻥ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﻳﻢ ﻫﺎ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫‪HTML 4.0‬‬

‫‪"‪"http://www.w3.org/TR/REC-html40/loose.dtd‬‬

‫ ‪ . HTML 4.0 Frameset‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﻳﻢ ﺭﺍ ﺩﺍﺭﺍ ﺍﺳﺖ‪.‬‬‫‪"‪"http://www.w3.org/TR/REC-html40/frameset.dtd‬‬ ‫ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ‪Html‬‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻭﺏ ﺩﺭ ﺣﺮﻳﻢ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻧﺎﻡ "ﺻﻔﺤﺎﺕ ﻭﺏ" ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪.‬‬

‫ﺍﻧﺪﺍﺯﻩ ﻭﻧﻮﻉ ﻣﺤﺘﻮﻳﺎﺕ ﺍﻳﻦ ﻧﻮﻉ ﺻﻔﺤﺎﺕ ﮐﺎﻣﻼ" ﻣﺘﻐﻴﺮ ﺑﻮﺩﻩ ﻭ ﻧﻤﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻳﮏ‬ ‫ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﺑﺎ ﻳﮏ ﺻﻔﺤﻪ ﮐﺘﺎﺏ ﻣﻘﺎﻳﺴﻪ ﮐﺮﺩ ﮔﺮﭼﻪ ﺷﺒﺎﻫﺖ ﻫﺎﻱ ﺍﻧﺪﮐﻲ ﻧﻴﺰ ﺑﻴﻦ ﺁﻧﻬﺎ‬ ‫ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪.‬‬

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‫ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﻳﺴﺘﺎ ‪ ،‬ﺍﻣﺮﻭﺯﻩ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺏ‪ ،‬ﺑﺎ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﮐﻪ ﺷﺎﻣﻞ‬

‫ﺗﻌﺪﺍﺩ ﺑﻴﺸﻤﺎﺭﻱ ﺍﺯ ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﻳﺴﺘﺎ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﺮﺧﻮﺭﺩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪ .‬ﻭﺍﮊﻩ " ﺍﻳﺴﺘﺎ "‪ ،‬ﺩﺭ‬ ‫ﺭﺍﺑﻄﻪ ﺑﺎ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﺩﺍﺭﺍﻱ ﭼﻪ ﺗﻌﺮﻳﻔﻲ ﺍﺳﺖ؟ ﺍﻳﻦ ﻧﻮﻉ ﺻﻔﺤﺎﺕ‪ ،‬ﺻﻔﺤﺎﺗﻲ ﻫﺴﺘﻨﺪ‬

‫ﻛﻪ ﺷﺎﻣﻞ ﻛﺪﻫﺎﻱ ‪ Html‬ﺑﻮﺩﻩ ﻭ ﺩﺭ ﻳﻚ ﻣﺤﻴﻂ ﺍﺩﻳﺘﻮﺭ ﺗﺎﻳﭗ ﻭ ﺑﺎ ﺍﻧﺸﻌﺎﺏ ‪ Htm‬ﻭ ﻳﺎ‬

‫‪ Html‬ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﻮﻟﻒ ﺻﻔﺤﻪ ﻭﺏ ﻗﺒﻞ ﺍﺯ ﺍﻳﻨﻜﻪ ﻫﺮ ﻧﻮﻉ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ ﺁﻥ‬ ‫ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﺑﻄﻮﺭ ﻛﺎﻣﻞ ﻣﺤﺘﻮﻱ ﺻﻔﺤﻪ ﺭﺍ ﻣﺸﺨﺺ ﻛﺮﺩﻩ ﺍﺳﺖ‪ .‬ﻣﺤﺘﻮﻳﺎﺕ ﺍﻳﻦ ﻧﻮﻉ‬

‫ﺍﺯ ﺻﻔﺤﺎﺕ )ﻣﺘﻦ‪ ،‬ﺗﺼﻮﻳﺮ‪ ،‬ﻟﻴﻨﻚ ﻫﺎ ﻭ…( ﻭ ﺷﻜﻞ ﻇﺎﻫﺮﻱ ﺁﻧﻬﺎ ﻫﻤﻮﺍﺭﻩ ﻳﻜﺴﺎﻥ ﺧﻮﺍﻫﺪ‬ ‫ﺑﻮﺩ‪ ،‬ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﺍﻳﻨﻜﻪ ﭼﻪ ﻛﺴﻲ‪ ،‬ﺩﺭ ﭼﻪ ﺯﻣﺎﻧﻲ ﻭ ﻳﺎ ﭼﮕﻮﻧﻪ ﺻﻔﺤﻪ ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﺧﻮﺍﻫﺪ‬ ‫ﻛﺮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻲ ﺗﻮﺍﻥ ﮔﻔﺖ‪ ،‬ﻣﺤﺘﻮﻳﺎﺕ ﺍﻳﻦ ﻗﺒﻴﻞ ﺍﺯ ﺻﻔﺤﺎﺕ ﻗﺒﻞ ﺍﺯ ﺍﻳﻨﻜﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ‬

‫ﺍﻳﺠﺎﺩ ﮔﺮﺩﺩ ‪ ،‬ﺗﻮﺳﻂ ﻣﺪﻳﺮﻳﺖ ﺳﺎﻳﺖ ﺍﻳﺠﺎﺩ ﻭ ﻣﺸﺨﺺ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬

‫ﻣﺮﺍﺣﻞ ﺁﻣﺎﺩﻩ ﺳﺎﺯﻱ ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﻳﺴﺘﺎ‬ ‫‪ – ١‬ﻳﻚ ﻣﻮﻟﻒ ﺻﻔﺤﻪ ﺍﻱ ﺭﺍ ﻛﻪ ﺷﺎﻣﻞ ﻛﺪﻫﺎﻱ ‪ Html‬ﺍﺳﺖ ﺭﺍ ﺍﻳﺠﺎﺩ ﻭ ﺁﻥ ﺭﺍ ﺑﺎ ﺍﻧﺸﻌﺎﺏ‬ ‫‪ Htm‬ﻭ ﻳﺎ ‪ Html‬ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪15‬‬

‫‪ – ٢‬ﮐﺎﺭﺑﺮﻱ ﺍﺯ ﻃﺮﻳﻖ ﺑﺮﻧﺎﻣﻪ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ‪ ،‬ﺩﺭ ﺧﻮﺍﺳﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺻﻔﺤﻪ ﺭﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪،‬‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﻓﻮﻕ ﺍﺯ ﻣﺮﻭﺭﮔﺮ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫‪ – ٣‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‪ ،‬ﻓﺎﻳﻞ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺎ ﺍﻧﺸﻌﺎﺏ ‪ Htm‬ﻭ ﻳﺎ ‪ Html‬ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ‬ ‫ﻛﺮﺩ‪.‬‬ ‫‪ – ٤‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‪ ،‬ﻛﺪﻫﺎﻱ ‪ Html‬ﻓﺎﻳﻞ ﻣﺰﺑﻮﺭ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﻜﻪ ﺑﺮﺍﻱ ﻣﺮﻭﺭﮔﺮ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻴﺪﺍﺭﺩ‪.‬‬ ‫‪ – ٥‬ﻣﺮﻭﺭﮔﺮ ﻛﺪﻫﺎﻱ ‪ Html‬ﺭﺍ ﭘﺮﺩﺍﺯﺵ ﻭ ﺻﻔﺤﻪ ﻓﻮﻕ ﺭﺍ ﻧﻤﺎﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﻳﺴﺘﺎ‬ ‫ﻓﺮﺽ ﻛﻨﻴﺪ ﻣﻲ ﺧﻮﺍﻫﻴﻢ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﻃﺮﺍﺣﻲ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﻛﻪ ﺑﻤﺤﺾ ﻭﺭﻭﺩ‬ ‫ﻫﺮ ﻛﺎﺭﺑﺮ ﺯﻣﺎﻥ ﺟﺎﺭﻱ ﺳﻴﺴﺘﻢ ﺑﻬﺮﺍﻩ ﻳﻚ ﭘﻴﺎﻡ ﻣﻨﺎﺳﺐ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺷﻮﺩ‪ ..‬ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﺎ‬ ‫ﭼﻨﺪﻳﻦ ﻣﺤﺪﻭﺩﻳﺖ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ ﻛﻪ ﺑﻜﻤﻚ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻃﺮﻑ ﻛﺮﺩﻥ‬

‫ﺁﻧﻬﺎ ﻧﺨﻮﺍﻫﻴﻢ ﺑﻮﺩ‪ .‬ﻣﺎ ﻣﻴﺪﺍﻧﻴﻢ ﻛﻪ ﻳﻚ ﻛﺎﺭﺑﺮ ﺩﺭ ﻳﻚ ﺯﻣﺎﻥ ﺧﺎﺹ ﺑﻪ ﻣﻼﻗﺎﺕ ﺻﻔﺤﻪ ﺧﻮﺍﻫﺪ‬ ‫ﺁﻣﺪ ﻭﻟﻲ ﻗﻄﻌﺎ؛ ﺯﻣﺎﻥ ﺁﻥ ﺭﺍ ﻧﻤﻲ ﺩﺍﻧﻴﻢ ‪.‬ﺍﮔﺮ ﺑﺨﻮﺍﻫﻴﻢ ﺯﻣﺎﻥ ﺭﺍ ﺑﺼﻮﺭﺕ ﻛﺪ ﺩﺭ ﺻﻔﺤﻪ ‪Html‬‬ ‫ﺧﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ‪ ،‬ﻧﺘﻴﺠﻪ ﻫﻤﻮﺍﺭﻩ ﻳﻜﺴﺎﻥ ﺑﻮﺩﻩ ﻭ ﻫﻤﻴﺸﻪ ﻳﻚ ﺯﻣﺎﻥ ﺛﺎﺑﺖ ﻭ ﻳﻜﺴﺎﻥ ﺑﺮﺍﻱ‬

‫ﺗﻤﺎﻣﻲ ﻣﻼﻗﺎﺕ ﻛﻨﻨﺪﮔﺎﻥ ﺻﻔﺤﻪ‪ ،‬ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺗﮓ ﻫﺎﻱ ‪ Html‬ﺍﻣﻜﺎﻧﺎﺗﻲ‬ ‫ﺑﻤﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﺳﻔﺎﺭﺷﻲ ﻭ ﺑﺮ ﺍﺳﺎﺱ ﺷﺮﺍﻳﻂ ﺧﺎﺹ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻗﺮﺍﺭ‬ ‫ﻧﻤﻲ ﺩﻫﺪ‪ .‬ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﻳﺴﺘﺎ ﻫﻤﻮﺍﺭﻩ ﺑﺼﻮﺭﺕ ﻣﺸﺎﺑﻪ ﻭ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﮐﺎﺭﺑﺮﺍﻥ‬ ‫ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ ) .‬ﻧﻈﻴﺮ ﺭﺳﺘﻮﺭﺍﻧﻲ ﻛﻪ ﻫﻤﻮﺍﺭﻩ ﻭ ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﺫﺍﺋﻘﻪ ﻣﺸﺘﺮﻳﺎﻥ ﺧﻮﺩ‪،‬‬ ‫ﻳﻚ ﻏﺬﺍﻱ ﺛﺎﺑﺖ ﻭ ﺍﺯ ﻗﺒﻞ ﺁﻣﺎﺩﻩ ﺷﺪﻩ ﺭﺍ ﺑﺮﺍﻱ ﻫﻤﻪ ﺁﻣﺎﺩﻩ ﻭ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﺪ!(‬ ‫‪ Html‬ﺩﺍﺭﺍﻱ ﻫﻴﭽﮕﻮﻧﻪ ﺍﻣﻨﻴﺘﻲ ﻧﻴﺰ ﻧﺒﻮﺩﻩ ﻭ ﻛﺪﻫﺎﻱ ﺁﻥ ﺭﺍ ﻫﻤﻪ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﻣﺸﺎﻫﺪﻩ ﻭ ﺣﺘﻲ‬ ‫‪16‬‬

‫ﺗﻜﺜﻴﺮ ﮔﺮﺩﺩ‪ .‬ﺷﺎﻳﺪ ﺗﻨﻬﺎ ﻣﺰﻳﺖ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺻﻔﺤﺎﺕ ﻃﺮﺍﺣﻲ ﺁﺳﺎﻥ ﻭ ﺑﮑﺎﺭﮔﻴﺮﻱ ﺳﺮﻳﻊ ﺁﻧﺎﻥ ﺩﺭ‬ ‫ﻳﻚ ﺷﺒﻜﻪ ﺑﺎﺷﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺻﻔﺤﺎﺕ ﺩﺍﺭﺍﻱ ﺍﻣﻜﺎﻧﺎﺕ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ ﺁﻓﺮﻳﻨﺶ ﺻﻔﺤﺎﺕ ﭘﻮﻳﺎ‬

‫ﻧﻴﺴﺘﻨﺪ‪ ،‬ﭼﻮﻥ ﻧﻤﻲ ﺗﻮﺍﻥ ﻛﺪﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺑﻌﺪ ﺍﺯ ﺩﺭﺧﻮﺍﺳﺖ ﻳﻚ ﺻﻔﺤﻪ ﺑﻪ ﺁﻥ‬ ‫ﺍﺿﺎﻓﻪ ﮐﺮﺩ ‪ .‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺪﻧﺒﺎﻝ ﺭﻭﺷﻲ ﻭ ﻳﺎ ﺭﻭﺵ ﻫﺎﺋﻲ ﺑﻮﺩ ﮐﻪ ﺑﮑﻤﮏ ﺁﻧﻬﺎ ﺑﺘﻮﺍﻥ ﺻﻔﺤﺎﺕ‬ ‫ﻭﺏ ﭘﻮﻳﺎ ﺭﺍ ﺍﻳﺠﺎﺩ ﮐﺮﺩ‪ .‬ﺑﻤﻨﻈﻮﺭ ﻧﻴﻞ ﺑﻪ ﻫﺪﻑ ﻓﻮﻕ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻋﻤﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫‪ . page Client - side dynamic‬ﺑﻬﺮﻩ ﮔﻴﺮﻱ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﺋﻲ ﻛﻪ ﭘﻮﻳﺎﺋﻲ‬ ‫ﻳﻚ ﺻﻔﺤﻪ ﺭﺍ ﺍﺯ ﺟﺎﻳﮕﺎﻩ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺗﺤﻘﻖ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬ ‫‪ . page side dynamic - Server‬ﺑﻬﺮﻩ ﮔﻴﺮﻱ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﺋﻲ ﻛﻪ ﭘﻮﻳﺎﺋﻲ‬ ‫ﻳﻚ ﺻﻔﺤﻪ ﺭﺍ ﺍﺯ ﺟﺎﻳﮕﺎﻩ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺗﺤﻘﻖ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻗﺒﻞ ﺍﺯ ﭘﺮﺩﺍﺧﺘﻦ ﺑﻪ ﻫﺮ ﻳﻚ ﺍﺯ ﻣﻮﺍﺭﺩ ﻓﻮﻕ‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﻣﻔﻬﻮﻡ ﻭ ﺟﺎﻳﮕﺎﻩ ﻳﻚ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺑﻴﺸﺘﺮ ﺁﺷﻨﺎ ﺷﻮﻳﻢ ‪ .‬ﻳﻚ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺍﺳﺖ ﻛﻪ‬ ‫ﻣﺪﻳﺮﻳﺖ ﺻﻔﺤﺎﺕ ﻭﺏ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﮔﺮﻓﺘﻪ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﺠﻬﺰ ﺑﻪ‬

‫ﻣﺮﻭﺭﮔﺮﻫﺎ‪ ،‬ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺗﺎﻛﻨﻮﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻫﺎﻱ ﻭﺏ ﻣﺘﻌﺪﺩﻱ‬ ‫ﻃﺮﺍﺣﻲ ﻭ ﺑﻪ ﺑﺎﺯﺍﺭ ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﺳﺖ‪ … IIS ، Apache .‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﻫﺎ ﻫﺴﺘﻨﺪ‪ IIS .‬ﻣﺤﺼﻮﻝ ﺷﺮﮐﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺑﻮﺩﻩ ﻭ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﺯﻣﺎﻥ ﻧﺼﺐ ﻭﻳﻨﺪﻭﺯ‬ ‫) ‪ ٢٠٠٠‬ﻭ ﻳﺎ ‪ (XP‬ﺁﻥ ﺭﺍ ﻧﻴﺰ ﻧﺼﺐ ﻧﻤﻮﺩ‪.‬ﻧﺴﺨﻪ ‪ ٥‬ﺑﻬﻤﺮﺍﻩ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﻭ ﻧﺴﺨﻪ ‪٥,١‬‬

‫ﺑﻬﻤﺮﺍﻩ ‪ XP‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﺑﻬﺮﺣﺎﻝ ﺟﺎﻳﮕﺎﻩ ﻳﻚ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺩﺭ ﺍﺭﺍﺋﻪ ﺍﻣﻜﺎﻧﺎﺕ‬ ‫ﻭ ﺯﻳﺮﺳﺎﺧﺖ ﻫﺎﻱ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﻃﺮﺍﺣﻲ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﻭ ﺑﺎﻟﻄﺒﻊ ﺳﺎﻳﺖ ﻫﺎﻱ ﭘﻮﻳﺎ ﻳﻚ‬ ‫ﺍﻣﺮ ﺑﺮﺟﺴﺘﻪ ﺍﺳﺖ‪ .‬ﻫﻤﺎﻧﮕﻮﻧﻪ ﻛﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﺑﺮﺍﻱ ﺧﻠﻖ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺍﺯ ﺩﻭ ﺭﻭﻳﻜﺮﺩ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﻫﻤﺰﻣﺎﻥ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻓﻮﻕ ﻫﻴﭽﮕﻮﻧﻪ ﺗﻌﺎﺭﺿﻲ ﺑﺎ ﻫﻢ‬

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‫ﻧﺪﺍﺷﺘﻪ ﺑﻠﻜﻪ ﺑﺎﻟﻌﻜﺲ ﺗﻮﺍﻧﺎﺋﻲ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﭘﻮﻳﺎ ﺭﺍ ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ‬ ‫ﺩﻭ ﺭﻭﻳﻜﺮﺩ ﻓﻮﻕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫‪ . page Client-side dynamic‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻣﺎﮊﻭﻝ ﻫﺎﺋﻲ ) ‪ ( Plug –in‬ﻛﻪ ﺑﻪ‬ ‫ﻣﺮﻭﺭﮔﺮ ﻣﻠﺤﻖ ﺷﺪﻩ ﺍﻧﺪ‪ ،‬ﺗﻤﺎﻣﻲ ﻋﻤﻠﻴﺎﺕ ﻻﺯﻡ ﺟﻬﺖ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﭘﻮﻳﺎ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ‬ ‫ﺩﺍﺩ‪ .‬ﻛﺪﻫﺎﻱ ‪ Html‬ﺍﺯ ﻃﺮﻳﻖ ﻓﺎﻳﻞ ﻣﺮﺑﻮﻃﻪ ﻛﻪ ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺍﺳﺖ‬

‫ﺑﺮﺍﻱ ﻣﺮﻭﺭﮔﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬ﻣﺮﻭﺭﮔﺮﻫﺎ ﺩﺳﺘﻮﺭﺍﺕ ﻓﻮﻕ ﺭﺍ ﺟﻬﺖ ﺗﻮﻟﻴﺪ ﻛﺪﻫﺎﻱ ‪Html‬‬ ‫ﻭ ﺩﺭ ﺯﻣﺎﻥ ﺩﺭﺧﻮﺍﺳﺖ ﻳﻚ ﺻﻔﺤﻪ ﺗﻮﺳﻂ ﻛﺎﺭﺑﺮ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﻨﺪ ﻛﺮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﺤﺘﻮﻳﺎﺕ‬ ‫ﻳﻚ ﺻﻔﺤﻪ ﺑﺮ ﺍﺳﺎﺱ ﺩﺭﺧﻮﺍﺳﺖ ﻛﺎﺭﺑﺮﺍﻥ ﻭ ﺑﺼﻮﺭﺕ ﭘﻮﻳﺎ ﺍﻳﺠﺎﺩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻣﺮﺍﺣﻞ ﺁﻣﺎﺩﻩ ﺷﺪﻥ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﭘﻮﻳﺎ ﺑﺎ ﺗﺎﻛﻴﺪ ﺑﺮ ﺭﻭﺵ ﻫﺎﻱ ‪Client-Side‬‬ ‫‪ – ١‬ﻳﻚ ﻣﻮﻟﻒ ﺻﻔﺤﻪ ﻭﺏ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﺭﺍ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻛﺪﻫﺎﻱ ‪Html‬‬ ‫ﻧﻮﺷﺘﻪ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺩﺭ ﻓﺎﻳﻠﻲ ﺑﺎ ﺍﻧﺸﻌﺎﺏ ‪ Html‬ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫‪ – ٢‬ﻛﺎﺭﺑﺮﺍﻥ ﺩﺭﺧﻮﺍﺳﺖ ﻳﻚ ﺻﻔﺤﻪ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‬ ‫ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﻛﺮﺩ‪.‬‬ ‫‪ – ٣‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﺎﻳﻞ ﺩﺭﺧﻮﺍﺳﺘﻲ )ﺩﺭ ﺻﻮﺭﺕ ﻧﻴﺎﺯ ﻓﺎﻳﻞ ﺩﻳﮕﺮﻱ ﻛﻪ ﺷﺎﻣﻞ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ‬ ‫ﻫﺎ ﺑﺎﺷﺪ( ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﻛﺮﺩ‪.‬‬ ‫‪ – ٤‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻓﺎﻳﻞ ﺣﺎﻭﻱ ﻛﺪﻫﺎﻱ ‪ Html‬ﻭ ﺩﺭ ﺻﻮﺭﺕ ﻭﺟﻮﺩ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ‬ ‫ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺑﺮﺍﻱ ﻣﺘﻘﺎﺿﻲ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﻛﺮﺩ‪.‬‬ ‫‪ – ٥‬ﻳﻚ ﻣﺎﮊﻭﻝ ﻫﻤﺮﺍﻩ ﻣﺮﻭﺭﮔﺮ ‪ ،‬ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺭﺍ ﭘﺮﺩﺍﺯﺵ ﻭ ﻛﺪﻫﺎﻱ ‪ Html‬ﺭﺍ ﺩﺭ ﻫﻤﺎﻥ‬ ‫ﺻﻔﺤﻪ ‪ Html‬ﺑﺮﻣﻲ ﮔﺮﺩﺍﻧﺪ‪.‬‬ ‫‪ – ٦‬ﺩﺭ ﻧﻬﺎﻳﺖ ﻛﺪﻫﺎﻱ ‪ Html‬ﺗﻮﺳﻂ ﻣﺮﻭﺭﮔﺮ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪.‬‬ ‫ﺗﺎﻛﻨﻮﻥ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺑﺮ ﺍﺳﺎﺱ ﺭﻭﻳﻜﺮﺩ ﻓﻮﻕ ﻣﻄﺮﺡ ﻭ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻃﺮﺍﺣﺎﻥ ﻭ ﻣﻮﻟﻔﺎﻥ‬ ‫ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺟﺎﻭﺍ ﺍﺳﻜﺮﻳﭙﺖ‪ ،Vbscript ،‬ﻛﻨﺘﺮﻝ ﻫﺎﻱ‬

‫‪ ActiveX‬ﻭ ﺍﭘﻠﺖ ﻫﺎﻱ ﺟﺎﻭﺍ ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻫﺎ ﺑﻮﺩﻩ ﻛﻪ ﺑﺮﺍﻱ ﺷﻨﺎﺧﺖ‬ ‫ﺧﻮﺍﻧﻨﺪﮔﺎﻥ ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﺑﺼﻮﺭﺕ ﺧﻴﻠﻲ ﻣﺨﺘﺼﺮ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻫﺮ ﻳﻚ ﺗﻮﺿﻴﺤﺎﺗﻲ ﺍﺭﺍﺋﻪ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ )‪، (JavaScript‬ﺍﻭﻟﻴﻦ ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺮﻭﺭﮔﺮﻫﺎ ﺍﺳﺖ‪.‬‬

‫ﺯﺑﺎﻧﻬﺎﻱ ﺍﺳﻜﺮﻳﭙﺖ ﺑﻌﻨﻮﺍﻥ ﺣﺪ ﻣﻴﺎﻧﻪ ﺑﻴﻦ ﻛﺪﻫﺎﻱ ‪ Html‬ﻭ ﺯﺑﺎﻧﻬﺎﻱ ﻣﻌﻤﻮﻟﻲ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ‬ ‫ﻗﺮﺍﺭ ﺩﺍﺷﺘﻪ ﻭ ﺑﺼﻮﺭﺕ ﻣﻔﺴﺮ ﻋﻤﻞ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﺭﺍ ﻧﺒﺎﻳﺪ ﺑﺎ ﺯﺑﺎﻥ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ‬ ‫ﺟﺎﻭﺍ ﺍﺷﺘﺒﺎﻩ ﮔﺮﻓﺖ‪ .‬ﺷﺮﻛﺖ ﻧﺖ ﺍﺳﻜﻴﭗ ﺩﺭ ﺍﺑﺘﺪﺍ ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺘﻲ ﺑﺎ ﻧﺎﻡ ‪ LiveScript‬ﭘﻴﺎﺩﻩ‬ ‫ﺳﺎﺯﻱ ﻭ ﺑﻬﻤﺮﺍﻩ ﻣﺮﻭﺭﮔﺮ ‪ NetScape 2.0‬ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ ﻗﺮﺍﺭ ﮔﺮﻓﺖ‪ .‬ﺯﻣﺎﻧﻴﻜﻪ‬

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‫ﺷﺮﻛﺖ ﻧﺖ ﺍﺳﻜﻴﭗ ﺑﺎ ﺷﺮﻛﺖ ‪ Sun‬ﻣﺘﺤﺪ ﮔﺮﺩﻳﺪ‪ ،‬ﻧﺎﻡ ﺁﻥ ﺭﺍ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﮔﺬﺍﺷﺘﻨﺪ‪.‬‬ ‫ﺑﺨﺸﻲ ﺍﺯ ﮔﺮﺍﻣﺮ ﺯﺑﺎﻥ ﻓﻮﻕ ﻧﻈﻴﺮ ﺳﺎﺧﺘﺎﺭ ﺍﻭﻟﻴﻪ‪ ،‬ﺍﺯ ﺟﺎﻭﺍ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺍﺳﺖ )ﺧﻮﺩ ﺟﺎﻭﺍ ﻧﻴﺰ‬ ‫ﺍﻏﻠﺐ ﺳﺎﺧﺘﺎﺭ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﺯﺑﺎﻥ ‪ C‬ﮔﺮﻓﺘﻪ ﺍﺳﺖ(‪ .‬ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﺩﺍﺭﺍﻱ ﺍﻣﻜﺎﻧﺎﺕ ﻣﺘﻌﺪﺩ ﻭ‬

‫ﻗﺪﺭﺗﻤﻨﺪﻱ ﺟﻬﺖ ﻛﻨﺘﺮﻝ ﻭ ﻣﺪﻳﺮﻳﺖ ﺭﻓﺘﺎﺭ ﻭ ﻣﺤﺘﻮﻳﺎﺕ ﻳﻚ ﻣﺮﻭﺭﮔﺮ ﺍﺳﺖ‪ .‬ﺯﺑﺎﻥ ﻓﻮﻕ ﺗﻮﺍﻧﺎﺋﻲ‬ ‫ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺗﻲ ﻧﻈﻴﺮ ‪ :‬ﻋﻤﻠﻴﺎﺕ ﺭﻭﻱ ﻓﺎﻳﻞ ﻫﺎ ﺭﺍ ﺩﺍﺭﺍ ﻧﻤﻲ ﺑﺎﺷﺪ‪) .‬ﺷﺎﻳﺪ ﻳﻜﻲ ﺍﺯ ﺩﻻﻳﻞ ﻣﺴﺎﺋﻞ‬ ‫ﺍﻣﻨﻴﺘﻲ ﺑﺎﺷﺪ(‪ .‬ﻓﺮﺍﮔﻴﺮﻱ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﻧﺴﺒﺖ ﺑﻪ ﺟﺎﻭﺍ ﺑﻤﺮﺍﺗﺐ ﺭﺍﺣﺖ ﺗﺮ ﺍﺳﺖ‪ .‬ﺟﺎﻭﺍ‬

‫ﺍﺳﻜﺮﻳﭙﺖ ﺑﮕﻮﻧﻪ ﺍﻱ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﺳﺖ ﻛﻪ ﻗﺎﺩﺭ ﺑﻪ ﺧﻠﻖ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻛﻮﭼﻚ ﻭ ﺩﺭ ﻋﻴﻦ ﺣﺎﻝ‬ ‫ﻣﻮﺛﺮ ﺟﻬﺖ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ﺑﺮﺧﻮﺭﺩ ﺑﺎ ﺭﻭﻳﺪﺍﺩﻫﺎﻱ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ ﺩﺭ ﺳﻄﺢ ﻛﺎﺭﺑﺮ‬ ‫ﻧﻈﻴﺮ‪ :‬ﻛﻠﻴﻚ ﻧﻤﻮﺩﻥ ﺑﺮ ﺭﻭﻱ ﻳﻚ ﺁﻳﺘﻢ‪ ،‬ﺑﺴﺘﻦ ﻳﻚ ﭘﻨﺠﺮﻩ‪ ،‬ﻓﻌﺎﻝ ﺷﺪﻥ ﻳﻚ ﺻﻔﺤﻪ‪ ،‬ﺧﺎﺭﺝ‬

‫ﺷﺪﻥ ﺍﺯ ﻳﻚ ﺻﻔﺤﻪ‪ ،‬ﺣﺮﻛﺖ ﻣﻮﺱ ﺭﻭﻱ ﻳﻚ ﺁﻳﺘﻢ ﻭ…ﺍﺳﺖ‪ .‬ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ﻧﺴﺨﻪ ﺍﺧﺘﺼﺎﺻﻲ‬

‫ﺧﻮﺩ ﺍﺯ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﺭﺍ ﺑﺎ ﻧﺎﻡ ‪ Jscript‬ﻭ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻣﻌﺮﻓﻲ ﻣﺮﻭﺭﮔﺮ ‪ IE 3.0‬ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬ ‫ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ ﻗﺮﺍﺭ ﺩﺍﺩ‪.‬‬ ‫‪ . Vbscript‬ﺷﺮﻛﺖ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻋﺮﺿﻪ ﻣﺮﻭﺭﮔﺮ ‪ IE 3.0‬ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺖ‬

‫ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﻳﻌﻨﻲ ‪ Vbscript‬ﺭﺍ ﻣﻄﺮﺡ ﻧﻤﻮﺩ‪ .‬ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺖ ﻓﻮﻕ ﺑﺮ ﺍﺳﺎﺱ ﺯﺑﺎﻥ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﻭﻳﮋﻭﺍﻝ ﺑﻴﺴﻴﻚ ﻭ ﺑﺎ ﻫﺪﻑ ﺭﻗﺎﺑﺖ ﺑﺎ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ‬

‫ﻗﺮﺍﺭ ﮔﺮﻓﺖ ‪ .‬ﺷﺎﻳﺪ ﺍﺯ ﻣﻌﺪﻭﺩ ﺍﻣﺘﻴﺎﺯﺍﺕ ﺍﻳﻦ ﺯﺑﺎﻥ ﻧﺴﺒﺖ ﺑﻪ ﺟﺎﻭﺍﺳﻜﺮﻳﭙﺖ ﺑﺘﻮﺍﻥ ﺑﻪ ﻋﺪﻡ‬

‫ﺣﺴﺎﺳﻴﺖ ﺁﻥ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺣﺮﻭﻑ ﺑﺰﺭﮒ ﻭ ﻛﻮﭼﻚ )‪ (Case Sensitive‬ﻧﺎﻡ ﺑﺮﺩ‪ .‬ﻛﺪﻫﺎﻱ‬

‫ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺯﺑﺎﻥ ﻓﻮﻕ ﺻﺮﻓﺎ؛ ﺍﺯ ﻃﺮﻳﻖ ﻣﺮﻭﺭﮔﺮ ﺷﺮﻛﺖ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ )‪ (IE‬ﻗﺎﺑﻞ‬ ‫ﺗﻔﺴﻴﺮ ﻭ ﺍﺟﺮﺍ ﺑﻮﺩﻩ ﻭ ﻧﺖ ﺍﺳﻜﻴﭗ ﺍﻳﻦ ﺯﺑﺎﻥ ﺭﺍ ﺣﻤﺎﻳﺖ ﻧﻤﻲ ﻛﻨﺪ‪ ،‬ﮔﺮﭼﻪ ﺑﺎ ﺍﻓﺰﻭﺩﻥ ﺑﺮﺧﻲ‬ ‫‪ Plug-In‬ﺍﻣﻜﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻦ ﺯﺑﺎﻥ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﻧﺖ ﺍﺳﻜﻴﭗ ﻧﻴﺰ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﺑﺎﻥ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﺑﻤﺮﺍﺗﺐ ﻧﺴﺒﺖ ﺑﻪ ﺯﺑﺎﻥ ‪ Vbscript‬ﺭﺍﻳﺞ ﺗﺮ ﺍﺳﺖ‪ .‬ﺍﮔﺮ ﻗﺼﺪ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻳﻚ ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺖ ﺑﺮﺍﻱ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻣﺘﻜﻲ ﺑﺮ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪،‬‬

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‫ﺑﺪﻭﻥ ﺷﻚ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﻳﻚ ﮔﺰﻳﻨﻪ ﻣﻨﺎﺳﺐ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺟﺎﻭﺍﺳﻜﺮﻳﭙﺖ ﻭ ‪ Vbscript‬ﻫﺮ‬ ‫ﺩﻭ ﺑﻌﻨﻮﺍﻥ ﻳﻚ ﻣﺎﮊﻭﻝ ﺑﺎ ﻧﺎﻡ ‪ Script Engine‬ﻛﻪ ﺑﻬﻤﺮﺍﻩ ﻣﺮﻭﺭﮔﺮﻫﺎ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪،‬‬ ‫ﻣﺴﺌﻮﻟﻴﺖ ﺗﻔﺴﻴﺮ ﻭ ﺍﺟﺮﺍﻱ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪ .‬ﺩﺭ ﭘﺮﻭﮊﻩ‬ ‫ﺩﺍﺕ ﻧﺖ ﺷﺮﻛﺖ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ‪ VB.NET‬ﺭﺍ ﺟﺎﻳﮕﺰﻳﻦ ‪ Vbscript‬ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪.‬‬

‫ﻛﻨﺘﺮﻝ ﻫﺎﻱ ‪ ، ActiveX‬ﻳﻚ ﻛﻨﺘﺮﻝ ﺍﻛﺘﻴﻮﺍﻳﻜﺲ ﻋﻨﺼﺮﻱ ﺍﺳﺖ ﻛﻪ ﺗﻮﺳﻂ ﻳﻜﻲ ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﻧﻈﻴﺮ ‪ C++‬ﻭ ﻳﺎ ﺟﺎﻭﺍ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻧﻴﻜﻪ ﺍﻳﻦ ﻧﻮﻉ ﺍﻛﺘﻴﻮﺍﻳﻜﺲ‬

‫ﻫﺎ ﺭﺍ ﺑﻬﻤﺮﺍﻩ ﺻﻔﺤﺎﺕ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﺍﻣﻜﺎﻥ ﺍﻧﺠﺎﻡ ﺑﺨﺸﻲ ﺍﺯ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻜﻲ ﺑﺮ‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻧﻈﻴﺮ ﺍﻳﺠﺎﺩ ﻳﻚ ‪ ، Timer ، Bar Chart‬ﺗﺎﻳﻴﺪ ﻛﺎﺭﺑﺮ ﻭ ﻳﺎ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ‬

‫ﺑﺎﻧﻚ ﺍﻃﻼﻋﺎﺗﻲ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻛﻨﺘﺮﻝ ﻫﺎﻱ ﺍﻛﺘﻴﻮﺍﻳﻜﺲ ﺍﺯ ﻃﺮﻳﻖ ﺗﮓ >‪
‫ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﻨﺪ ﮔﺮﺩﻳﺪ‪ .‬ﻣﻨﺎﺩﻱ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺷﺮﻛﺖ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ﺑﻮﺩﻩ ﻭ ﺗﺎ‬

‫ﻧﺴﺨﻪ ﺷﺶ ﻣﺮﻭﺭﮔﺮ ﻧﺖ ﺍﺳﻜﻴﭗ ﺍﻣﻜﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﻬﺎ ﺗﻮﺳﻂ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪.‬‬ ‫ﺍﻟﺒﺘﻪ ﺑﺎ ﻧﺼﺐ ﺑﺮﺧﻲ ‪ Plug-in‬ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻛﻨﺘﺮﻝ ﻫﺎﻱ ﺍﻛﺘﻴﻮﺍﻳﻜﺲ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﻧﺖ‬

‫ﺍﺳﻜﻴﭗ ﺑﮕﻮﻧﻪ ﺍﻱ ﻓﺮﺍﻫﻢ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻧﻜﺘﻪ ﺟﺎﻟﺐ ﺗﻮﺟﻪ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﻳﻦ‬ ‫ﺍﺳﺖ ﻛﻪ ﺍﻣﻜﺎﻥ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺕ ﺑﺮ ﺭﻭﻱ ﻛﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻛﺎﺭﺑﺮﺍﻥ ﻧﻈﻴﺮ ﻛﺎﺭ ﺑﺎ ﻓﺎﻳﻞ ﻫﺎ‬ ‫ﻭ ﺭﻳﺠﺴﺘﺮﻱ ﻭﻳﻨﺪﻭﺯ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻳﺪ ﻭ ﺍﻳﻦ ﺧﻮﺩ ﻣﻲ ﺗﻮﺍﻧﺪ ﺍﺯ ﻟﺤﺎﻅ ﺍﻣﻨﻴﺘﻲ ﻣﺸﻜﻞ ﻭ ﮔﺎﻫﺎ "‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﺟﻮﺩ ﻓﺎﻳﺮﻭﺍﻝ ﻫﺎ ﺗﺤﻘﻖ ﻧﺎ ﭘﺬﻳﺮ ﺑﺎﺷﺪ‪ .‬ﺑﻬﺮﺣﺎﻝ ﻧﻤﻲ ﺗﻮﺍﻥ ﺑﺮ ﺭﻭﻱ ﺗﻜﻨﻮﻟﻮﮊﻱ‬

‫ﻓﻮﻕ ﺑﻌﻨﻮﺍﻥ ﻳﻚ ﺭﺍﻩ ﺣﻞ ﺟﺎﻣﻊ ﻭ ﻓﺮﺍﮔﻴﺮ ﺑﺮﺍﻱ ﺧﻠﻖ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻛﺮﺩ ﻣﮕﺮ‬ ‫ﺍﻳﻨﻜﻪ ﻣﺨﺎﻃﺒﺎﻥ ﺳﺎﻳﺖ ﺧﻮﺩ ﺭﺍ ﺻﺮﻓﺎ" ﺍﺯ ﺑﻴﻦ ﻛﺴﺎﻧﻲ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﻢ ﻛﻪ ﻭﻳﻨﺪﻭﺯ ﺭﺍ ﺑﻌﻨﻮﺍﻥ‬ ‫ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭ ﻣﺮﻭﺭﮔﺮ ‪ IE‬ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ ﺑﺮﮔﺰﻳﺪﻩ ﺍﻧﺪ‪.‬‬ ‫‪ ، Java Applet‬ﺟﺎﻭﺍ ﻳﻚ ﺯﺑﺎﻥ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﻣﺴﺘﻘﻞ ﺍﺯ ‪ Platform‬ﺍﺳﺖ‪ .‬ﺟﺎﻭﺍ ﻧﺴﺒﺖ‬

‫ﺑﻪ ﺯﺑﺎﻧﻬﺎﻱ ﺍﺳﻜﺮﻳﭙﺖ ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﻱ ﺍﺳﺖ‪ .‬ﻫﺪﻑ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻛﺪﻫﺎﻱ‬ ‫ﺟﺎﻭﺍ ﺑﻪ ﺷﻜﻞ ﺍﭘﻠﺖ ﺍﺳﺖ ‪ .‬ﻋﻨﺎﺻﺮ ﻓﻮﻕ ﺑﺴﺎﺩﮔﻲ ﻭ ﺗﻮﺳﻂ ﺗﮓ >‪ <Applet‬ﺑﻪ ﺻﻔﺤﺎﺕ‬ ‫‪21‬‬

‫ﻭﺏ ﻣﻠﺤﻖ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺧﻮﺷﺒﺨﺘﺎﻧﻪ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ ﻭ ﻧﺖ ﺍﺳﻜﻴﭗ ﻫﺮ ﺩﻭ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﺍﻳﺠﺎﺩ ﻳﻚ ﻣﺎﺷﻴﻦ ﻣﺠﺎﺯﻱ ﺟﺎﻭﺍ )‪ (JVM‬ﺍﺯ ﺍﭘﻠﺖ ﻫﺎﻱ ﺟﺎﻭﺍ ﺣﻤﺎﻳﺖ ﻣﻲ ﻛﻨﻨﺪ‪.‬‬ ‫ﺑﻤﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﭘﻠﺖ ﻫﺎﻱ ﺟﺎﻭﺍ ﺩﺭ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﺍﺯ ﭼﻨﺪﻳﻦ ﺭﻭﺵ ﻣﻲ ﺗﻮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻛﺮﺩ‪ :‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﮓ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ >‪ ‪. <Applet‬‬

‫ﺗﮓ ﻫﺎﻱ ﻓﻮﻕ ﺑﻪ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺍﻫﻨﺪ ﮔﻔﺖ ﻛﻪ ﻳﻚ ﻓﺎﻳﻞ ﺟﺎﻭﺍ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‬ ‫‪ DownLoad‬ﻭ ﺳﭙﺲ ﺑﻜﻤﻚ ﻣﺎﺷﻴﻦ ﻣﺠﺎﺯﻱ ﺟﺎﻭﺍ )‪ ، (JVM‬ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﺮﻭﺭﮔﺮﻫﺎ‪ ،‬ﺁﻥ‬

‫ﺭﺍ ﺍﺟﺮﺍﺀ ﻧﻤﺎﻳﺪ‪ .‬ﻫﻤﺎﻧﻄﻮﺭ ﻛﻪ ﺣﺪﺱ ﺯﺩﻩ ﺍﻳﺪ ﻳﻜﻲ ﺍﺯ ﻣﺴﺎﺋﻞ ﻣﻮﺟﻮﺩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺍﭘﻠﺖ ﻫﺎ ﺟﺎﻭﺍ ‪ ،‬ﺯﻣﺎﻥ ﺍﺿﺎﻓﻪ ﺍﻱ ﺍﺳﺖ ﻛﻪ ﺻﺮﻑ ‪ Download‬ﻛﺮﺩﻥ‪ ،‬ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭ‬ ‫ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﭘﻠﺖ ﻫﺎﻱ ﺟﺎﻭﺍ ‪ ،‬ﺳﻌﻲ ﺩﺭ ﻧﻮﺷﺘﻦ ﺍﭘﻠﺖ ﻫﺎ ﺑﺎ ﻛﺪ ﻛﻢ ﺑﺎﺷﻴﻢ‪ .‬ﺍﺯ ﺭﺍﻳﺞ ﺗﺮﻳﻦ‬

‫ﻣﻮﺍﺭﺩ ﻛﺎﺭﺑﺮﺩ ﺍﭘﻠﺖ ﻫﺎﻱ ﺟﺎﻭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﺍﻳﺠﺎﺩ ‪ Drop-Down Menu‬ﻭ ﺍﻧﻴﻤﻴﺸﻦ ﻫﺎﻱ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺍﺷﺎﺭﻩ ﻛﺮﺩ‪.‬‬ ‫‪ . Pages Server Side Dynamic‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ ﻛﺪﻫﺎﻱ ‪ Html‬ﺑﻬﻤﺮﺍﻩ ﻣﺠﻤﻮﻋﻪ ﺍﻱ‬

‫ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺭﺳﺎﻝ ﻭ ﻣﺠﺪﺩﺍ" ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻓﻮﻕ ﺑﺮﺍﻱ‬

‫ﺗﻮﻟﻴﺪ ﻛﺪﻫﺎﻱ ‪ Html‬ﺑﺮﺍﻱ ﺻﻔﺤﻪ ﺍﻱ ﻛﻪ ﻛﺎﺭﺑﺮ ﺩﺭﺧﻮﺍﺳﺖ ﻛﺮﺩﻩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ‬ ‫ﺻﻔﺤﻪ ﺑﺼﻮﺭﺕ ﭘﻮﻳﺎ ﺑﺮ ﺍﺳﺎﺱ ﺩﺭﺧﻮﺍﺳﺖ ﻛﺎﺭﺑﺮ ﺍﻳﺠﺎﺩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻣﺮﺍﺣﻞ ﺁﻣﺎﺩﻩ ﺷﺪﻥ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﭘﻮﻳﺎ ﺑﺎ ﺗﺎﻛﻴﺪ ﺑﺮ ﺭﻭﺵ ﻫﺎﻱ ‪Server-Side‬‬ ‫‪ – ١‬ﻳﻚ ﻣﻮﻟﻒ ﺻﻔﺤﻪ ﻭﺏ ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺭﺍ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻛﺪﻫﺎﻱ ‪Html‬‬ ‫ﻧﻮﺷﺘﻪ ﻭ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺭﺍ ﺩﺭ ﻳﻚ ﻓﺎﻳﻞ ﺫﺧﻴﺮﻩ ﻣﻲ ﻛﻨﺪ‪.‬‬ ‫‪ – ٢‬ﻛﺎﺭﺑﺮﺍﻥ ﺍﺯ ﻃﺮﻳﻖ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ‪ ،‬ﺩﺭﺧﻮﺍﺳﺖ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﻧﻤﻮﺩﻩ ﻭ ﺍﻳﻦ‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫‪ – ٣‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻣﺤﻞ ﻓﺎﻳﻞ ﺣﺎﻭﻱ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﻛﺮﺩ‪.‬‬ ‫‪ – ٤‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺩﺳﺘﻮﺭﺍﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻓﺎﻳﻞ ﺭﺍ ﺑﻤﻨﻈﻮﺭ ﺗﻮﻟﻴﺪ ﻛﺪ ‪ Html‬ﺍﺟﺮﺍﺀ‬ ‫ﺧﻮﺍﻫﺪ ﻛﺮﺩ‪.‬‬ ‫‪ – ٥‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻛﺪﻫﺎﻱ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺟﺪﻳﺪ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﻜﻪ ﺑﺮﺍﻱ ﻣﺮﻭﺭﮔﺮ ﺍﺭﺳﺎﻝ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫‪ – ٦‬ﻣﺮﻭﺭﮔﺮ ﻛﺪﻫﺎﻱ ‪ Html‬ﺭﺍ ﭘﺮﺩﺍﺯﺵ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ ﺻﻔﺤﻪ ﻭﺏ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﻳﻜﺘﻪ ﻣﻬﻢ ﺩﺭ ﺳﻨﺎﺭﻳﻮﻱ ﻓﻮﻕ‪ ،‬ﺍﺟﺮﺍﻱ ﺗﻤﺎﻣﻲ ﭘﺮﺩﺍﺯﺵ ﻫﺎ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﻗﺒﻞ ﺍﺯ‬

‫ﺍﺭﺳﺎﻝ ﺻﻔﺤﻪ ﺑﺮﺍﻱ ﻣﺮﻭﺭﮔﺮ ﺍﺳﺖ‪ .‬ﻳﻜﻲ ﺍﺯ ﻣﺰﺍﻳﺎﻱ ﻋﻤﺪﻩ ﻣﺪﻝ ﻓﻮﻕ ﻧﺴﺒﺖ ﺑﻪ ﻣﺪﻝ ‪Client-‬‬ ‫‪ ، Side‬ﺍﻳﻦ ﻣﻮﺭﺩ ﺍﺳﺖ ﻛﻪ ‪ :‬ﺩﺭ ﻳﻚ ﺻﻔﺤﻪ ﻭﺏ ﺻﺮﻓﺎ" ﺷﺎﻫﺪ ﻛﺪﻫﺎﻱ ‪ Html‬ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪.‬‬

‫ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﻲ ﺍﺳﺖ ﻛﻪ ﻣﻨﻄﻖ ﺻﻔﺤﺎﺕ ﻭﺏ ﺩﺭ ﻧﺰﺩ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻣﺨﻔﻲ ﻧﮕﻬﺪﺍﺭﻱ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ ﻭ ﻣﻲ ﺗﻮﺍﻥ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺩﺍﺷﺖ ﻛﻪ ﺍﻛﺜﺮ ﻣﺮﻭﺭﮔﺮﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﻧﻤﺎﻳﺶ ﻧﺘﺎﻳﺞ‬ ‫ﭘﺮﺩﺍﺯﺵ ﻫﺎ ﻱ ﺍﺟﺮﺍﺀ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺑﺎﺷﻨﺪ‪ ASP.NET .‬ﺍﺯ ﻣﺪﻝ ﻓﻮﻕ‬

‫ﺗﺒﻌﻴﺖ ﻣﻲ ﻛﻨﺪ‪ .‬ﻳﻜﻲ ﺩﻳﮕﺮ ﺍﺯ ﻧﻜﺎﺕ ﻣﻬﻢ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﺍﻳﻦ ﺍﺳﺖ ﻛﻪ ﻳﻚ ﺻﻔﺤﻪ‬ ‫ﺗﺎ ﺯﻣﺎﻧﻴﻜﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ ﺁﻥ ﺩﺭﻳﺎﻓﺖ ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﻣﺤﺘﻮﻳﺎﺕ ﺁﻥ ﺑﻮﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺁﻣﺪ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﺑﺮﺧﻲ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﻱ ﻣﺘﺪﺍﻭﻝ ﺩﺭﺍﻳﻦ ﻣﺪﻝ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫)‪ . CGI(Common Gateway Interface‬ﻣﻜﺎﻧﻴﺰﻣﻲ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺍﺳﻜﺮﻳﭙﺖ ﺑﺮ‬

‫ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺑﻮﺩﻩ ﺗﺎ ﺑﺪﻳﻦ ﻃﺮﻳﻖ ﺍﻣﻜﺎﻥ ﺍﻳﺠﺎﺩ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻱ ﻣﺘﻜﻲ ﺑﺮ ﻭﺏ ﻓﺮﺍﻫﻢ‬

‫ﮔﺮﺩﺩ‪ CGI .‬ﻣﺎﮊﻭﻟﻲ ﺍﺳﺖ ﻛﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺍﺿﺎﻓﻪ ﮔﺮﺩﺩ‪ .‬ﻗﺪﻣﺖ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ ‪ ASP‬ﺍﺳﺖ ﻭ ﺗﺎ ﻛﻨﻮﻥ ﺗﻌﺪﺍﺩ ﺑﻴﺸﻤﺎﺭﻱ ﺍﺯ‬ ‫ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﻭ ﺑﻜﻤﻚ ﻳﻚ ﺯﺑﺎﻥ ﺍﺳﻜﺮﻳﭙﺖ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‬

‫ﺍﻧﺪ‪ CGI .‬ﺍﻳﻦ ﺍﻣﻜﺎﻥ ﺭﺍ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﻛﺮﺩ ﻛﻪ ﻛﺎﺭﺑﺮ‪ ،‬ﻳﻚ ﺑﺮﻧﺎﻣﻪ ﺩﻳﮕﺮ ) ﻧﻈﻴﺮ ﻳﻚ‬ ‫ﺍﺳﻜﺮﻳﭙﺖ ‪ ( Perl‬ﺭﺍ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﺑﺎﻧﻬﺎﺋﻲ ﻧﻈﻴﺮ ‪ Perl , C ,C++‬ﺑﻬﻤﺮﺍﻩ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﺴﻴﺎﺭ ﺭﺍﻳﺞ ﺍﺳﺖ‪.‬‬

‫ﺑﻬﺮﺣﺎﻝ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﻣﺮﻭﺯﻩ ﺩﺭ ﺧﻴﻠﻲ ﺍﺯ ﺳﺎﻳﺖ ﻫﺎﻱ ﺑﺰﺭﮒ ﺧﺼﻮﺻﺎ" ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻜﻲ‬ ‫ﺑﺮ ﻳﻮﻧﻴﻜﻴﺲ ﺭﺍﻳﺞ ﺑﻮﺩﻩ ﻭ ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﭼﻨﺪﻳﻦ ‪ Platform‬ﺭﺍ ﺩﺍﺭﺍ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫)‪ ، ASP(Active Server Page‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﻛﻪ ﭘﺲ ﺍﺯ ﻋﺮﺿﻪ ‪ ASP.NET‬ﺑﺎ‬ ‫ﻧﺎﻡ ‪ ASP‬ﻛﻼﺳﻴﻚ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻳﻜﻲ ﺍﺯ ﻣﺘﺪﻭﺍﻟﺘﺮﻳﻦ ﺭﻭﺵ ﻫﺎﺏ ﻣﻮﺟﻮﺩ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‬ ‫ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺍﺳﺖ‪ .‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﺎ ﺑﻬﺮﻩ ﮔﻴﺮﻱ ﺍﺯ ﺗﻮﺍﻥ ﺯﺑﺎﻧﻬﺎﻱ‬

‫ﺍﺳﻜﺮﻳﭙﺖ ﻧﻈﻴﺮ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﻭ ‪ Vbscript‬ﺗﻮﺍﻧﺴﺘﻪ ﺍﺳﺖ ﭘﺎﺳﺦ ﺷﺎﻳﺴﺘﻪ ﺑﻪ ﻃﺮﺍﺡ ﺻﻔﺤﺎﺕ‬

‫ﻭﺏ ﭘﻮﻳﺎ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﺎﻳﺪ‪ ASP .‬ﻳﻚ ﻣﺎﮊﻭﻝ ﺟﺪﺍﮔﺎﻧﻪ ﺍﺳﺖ ﻛﻪ ﺩﺭ ﻛﻨﺎﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ‬ ‫ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﺩ) ‪ . ( ASP.dll‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﻧﺴﺒﺖ ﺑﻪ ﺑﺮﺧﻮﺩ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﻱ ﻫﻤﮕﺮﻭﻩ ﺍﺯ‬ ‫ﻛﺎﺭﺁﻳﻲ ﭘﺎﻳﻴﻦ ﺗﺮﻱ ﺑﺮﺧﻮﺭﺩﺍﺭ ﺑﻮﺩﻩ ﻭ ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﺑﺎﻧﻬﺎﺏ ﺍﺳﻜﺮﻳﭙﺖ ﺩﺭ ﻛﻨﺎﺭ ﺧﻮﺩ‪،‬‬

‫ﻧﻴﺰ ﺩﺍﺭﺍﻱ ﻣﺤﺪﻭﺩﻳﺖ ﺍﺳﺖ‪ .‬ﺑﻬﺮﺣﺎﻝ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﺎ ﺳﺎﺑﻘﻪ ﺷﺶ ﺳﺎﻟﻪ ﺗﺎﻛﻨﻮﻥ ﺗﻮﺍﻧﺴﺘﻪ‬ ‫ﺍﺳﺖ ﺑﻪ ﺧﻴﻞ ﻋﻈﻴﻢ ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎ ﺑﺮﺍﺏ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﭘﻮﻳﺎ ﺩﺭﺳﺖ ﭘﺎﺳﺦ ﺩﻫﺪ‪ ،‬ﻭﻟﻲ ﺑﺎ‬

‫ﻇﻬﻮﺭ ﺧﻮﺍﺳﺘﻪ ﻫﺎ ﻭ ﺍﻧﺘﻈﺎﺭﺍﺕ ﺟﺪﻳﺪ ﺑﻪ ﭼﺎﻟﺶ ﺟﺪﻱ ﻛﺸﻴﺪﻩ ﺷﺪﻩ ﺍﺳﺖ ﻭ ﺷﺎﻳﺪ ﻇﻬﻮﺭ ﻭ‬ ‫ﺗﻮﻟﺪ ‪ ASP.NET‬ﺩﻟﻴﻞ ﻭ ﭘﺎﺳﺨﻲ ﺑﻪ ﺑﺮﺧﻲ ﺍﺯ ﺍﻧﺘﻘﺎﺩﺍﺕ ﻣﻄﺮﻭﺣﻪ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﺎﺷﺪ‪.‬‬ ‫) ‪ ، JSP (JavaServer page‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﻣﻜﺎﻥ ﺗﺮﻛﻴﺐ ‪ Html‬ﻭﻳﺎ ‪ Xml‬ﺭﺍ ﺑﺎ‬ ‫ﻛﺪﻫﺎﻱ ﺟﺎﻭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻳﻦ ﻓﻨﺎﻭﺭﻱ ﺑﺮﺧﻼﻑ ‪ ASP‬ﻛﻪ ﺻﺮﻓﺎ" ﺗﻮﺳﻂ ﺳﺮﻭﻳﺲ‬

‫ﺩﻫﻨﺪﻩ ﻭﺏ ﻣﺎﻛﺮﻭﺳﺎﻓﺖ )‪ ( IIS‬ﺣﻤﺎﻳﺖ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺗﻮﺳﻂ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺣﻤﺎﻳﺖ ﺷﺪﻩ ﺍﺳﺖ‪ JSP .‬ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ‪ ASP‬ﺑﻤﺮﺍﺗﺐ ﺩﺍﺭﺍﻱ ﻗﺪﺭﺕ ﻭ ﺳﺮﻋﺖ ﺑﻴﺸﺘﺮﻱ ﺑﻮﺩﻩ‬

‫ﻭ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﺎﻥ ﺟﺎﻭﺍ ﺑﺨﻮﺑﻲ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺁﻥ ﺁﺷﻨﺎﺋﻲ ﺩﺍﺭﻧﺪ‪ JSP .‬ﺍﻳﻦ ﺍﻣﻜﺎﻥ ﺭﺍ‬ ‫ﻓﺮﺍﻫﻢ ﻣﻲ ﻛﻨﺪ ﻛﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺟﺎﻭﺍ ﺍﺯ ﻭﻳﮋﮔﻲ ﻣﺤﻴﻂ ﻫﺎﻱ ﻣﺘﻜﻲ ﺑﺮ ‪ Java2‬ﻧﻈﻴﺮ‬ ‫‪ JavaBeans‬ﻭ ‪ Java2 Libraries‬ﺑﺨﻮﺑﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫‪ . ColdFusion‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ‪ ،‬ﺍﻣﻜﺎﻥ ﺳﺎﺧﺖ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﺗﻜﻨﻮﻟﻮﮊﻱ ﺑﺼﻮﺭﺕ ﻳﻚ ﻣﺎﮊﻭﻝ ﺟﺪﺍﮔﺎﻧﻪ ﺍﺳﺖ ﻛﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮ ﺭﻭﻱ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻧﺼﺐ ﮔﺮﺩﺩ‪ .‬ﺻﻔﺤﺎﺗﻲ ﻛﻪ ﺗﻮﺳﻂ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻳﻨﺪ‪،‬‬

‫ﺗﻮﺳﻂ ﻫﺮ ﻧﻮﻉ ﻣﺮﻭﺭﮔﺮﻱ ﻗﺎﺑﻞ ﺧﻮﺍﻧﺪﻥ ﻭ ﻧﻤﺎﻳﺶ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

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‫ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺯﻳﺎﺩﻱ ﺗﮓ ﻛﻪ ﺗﻮﺳﻂ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ ColdFusion‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ‬

‫ﺍﺳﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻛﻨﺪ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻓﻮﻕ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻣﺘﻌﺪﺩﻱ ﺣﺘﻲ ‪IIS‬‬ ‫ﻧﺼﺐ ﻭ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺳﺖ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﻣﺴﺌﻠﻪ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺩﺭ ﺍﻳﻦ ﺍﺳﺖ ﻛﻪ ﺍﺯ‬

‫ﺗﮓ ﻫﺎﻱ ‪ Html-Like‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ) ﺩﺭ ‪ ASP.NET‬ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﻭ‬

‫ﺍﺷﻴﺎﺀ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ(‪ .‬ﻳﻜﻲ ﺩﻳﮕﺮ ﺍﺯ ﻧﻜﺎﺕ ﻣﻬﻢ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺩﺭ ﺍﻳﻦ ﺍﺳﺖ‬ ‫ﻛﻪ ﺗﻬﻴﻪ ﺁﻥ ﺭﺍﻳﮕﺎﻥ ﻧﺒﻮﺩﻩ ﻭ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻴﺶ ﺍﺯ ﻫﺰﺍﺭ ﺩﻻﺭ ﺑﺮﺍﻱ ﺗﻬﻴﻪ ﺁﻥ ﻫﺰﻳﻨﻪ ﻧﻤﻮﺩ!‬ ‫‪ ، PHP‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﻛﻪ ﺩﺭ ﺍﺑﺘﺪﺍ ‪ Personal Home Page‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﺪ ﻭ ﺍﺧﻴﺮﺍ؛‬ ‫‪ PHP Hypertext Preprocessor‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻳﻜﻲ ﺩﻳﮕﺮ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﻱ ﺭﺍﻳﺞ‬

‫ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﭘﻮﻳﺎ ﺍﺳﺖ‪ .‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﺮ ﺧﻼﻑ ‪ . ASP.NET‬ﺑﺼﻮﺭﺕ‬

‫‪ Cross-Platform‬ﺑﻮﺩﻩ ﻭ ﺑﺮ ﺭﻭﻱ ﺍﻏﻠﺐ ﺳﻴﺴﺘﻢ ﻫﺎ ﻧﻈﻴﺮ ﻭﻳﻨﺪﻭﺯ ‪ NT‬ﻭ ﺍﻏﻠﺐ ﻧﺴﺨﻪ‬ ‫ﻫﺎﻱ ﻳﻮﻧﻴﻜﺲ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺳﺖ‪ .‬ﮔﺮﺍﻣﺮ ﺯﺑﺎﻥ ﻓﻮﻕ ﻧﻈﻴﺮ ‪ C‬ﻭ ‪ Perl‬ﺍﺳﺖ‪ .‬ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ‬

‫ﺩﺍﺭﺍﻱ ﺑﺮﺧﻲ ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﺷﻲ ﮔﺮﺍﺀ ﺑﻮﺩﻩ ﻛﻪ ﺍﻣﻜﺎﻥ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﻛﭙﺴﻮﻟﻪ‬

‫ﻧﻤﻮﺩﻥ ﻛﺪﻫﺎ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﺩ‪.‬‬ ‫‪ ، ASP.NET‬ﭘﺲ ﺍﺯ ﻣﻌﺮﻓﻲ ﺗﻜﻨﻮﻟﻮﮊﻳﻬﺎﻱ ﺭﺍﻳﺞ ﺩﺭ ﺍﻳﻦ ﮔﺮﻭﻩ‪ ،‬ﺯﻣﻴﻨﻪ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ‬ ‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﺗﻜﻨﻮﻟﻮﮊﻱ ‪ ASP.NET‬ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ ﺍﺳﺖ‪ ASP.NET .‬ﻧﻴﺰ ﺑﻌﻨﻮﺍﻥ ﻳﻚ ﻣﺎﮊﻭﻝ‬ ‫ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﺩ )‪ .( aspnetIsapi.dll‬ﺩﺭ ﻛﻨﺎﺭ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ‬

‫ﻣﺠﻤﻮﻋﻪ ﻋﻈﻴﻢ ﺩﺍﺕ ﻧﺖ ﻗﺮﺍﺭ ﺩﺍﺭﺩ‪ ASP .‬ﻛﻼﺳﻴﻚ ﺩﺭﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ‬ ‫ﺍﺳﻜﺮﻳﭙﺖ ﻣﺤﺪﻭﺩ ﺑﻮﺩﻩ ﻭ ﺻﺮﻓﺎ؛ ﺑﻪ ﺟﺎﻭﺍﺍﺳﻜﺮﻳﭙﺖ ﻭ ‪ Vbscript‬ﺧﺘﻢ ﻣﻲ ﮔﺮﺩﺩ‬ ‫)‪ Vbscript‬ﻫﻢ ﺻﺮﻓﺎ" ﺗﻮﺳﻂ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺘﻜﻲ ﺑﺮ ﻭﻳﻨﺪﻭﺯ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ(‬ ‫‪ ASP.NET.‬ﺍﻣﻜﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﻭﺳﻴﻌﻲ ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﺭﺍ ﻓﺮﺍﻫﻢ‬

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‫ﻣﻲ ﻛﻨﺪ‪ .‬ﺯﺑﺎﻧﻬﺎﺋﻲ ﻧﻈﻴﺮ ‪ Python, Perl ، Jscript.NET ، C# ، VB.NET‬ﻧﻤﻮﻧﻪ‬ ‫ﻫﺎﺋﻲ ﺍﺯ ﺯﺑﺎﻧﻬﺎﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺁﻧﻬﺎ ﺑﻬﻤﺮﺍﻩ ‪ ASP.NET‬ﺍﺳﺘﻔﺎﺩﻩ ﻛﺮﺩ‪.‬‬ ‫ﺍﻣﺮﻭﺯﻩ ﺑﻴﺶ ﺍﺯ ﭘﺎﻧﺼﺪ ﻣﻴﻠﻴﻮﻥ ﻧﻔﺮ ﺩﺭ ﺳﺮﺍﺳﺮ ﺩﻧﻴﺎ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺗﻌﺪﺍﺩ ﺻﻔﺤﺎﺕ ﻭﺏ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻣﺮﺯ ﭼﻬﺎﺭ ﻣﻴﻠﻴﺎﺭﺩ ﮔﺬﺷﺘﻪ ﻭ ﻫﻤﭽﻨﺎﻥ ﺍﻳﻦ ﺭﻭﻧﺪ ﺑﺎ‬

‫ﺳﺮﻋﺘﻲ ﺑﺎﻭﺭﻧﮑﺮﺩﻧﻲ ﺭﻭ ﺑﻪ ﺍﻓﺰﺍﻳﺶ ﺍﺳﺖ‪ .‬ﺣﺠﻢ ﻣﺒﺎﺩﻻﺕ ﺗﺠﺎﺭﻱ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﺯ ﻣﺮﺯ‬ ‫ﻧﻴﻢ ﺗﺮﻳﻠﻴﻮﻥ ﺩﻻﺭ ﮔﺬﺷﺘﻪ ﻭ ﺍﻓﻖ ﺟﺪﻳﺪﻱ ﺭﺍ ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﺑﻨﮕﺎﻩ ﻫﺎﻱ ﺗﺠﺎﺭﻱ ﺩﺭ ﺳﺮﺗﺎﺳﺮ ﺩﻧﻴﺎ‬

‫ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺭﺷﺪ ﻭ ﮔﺴﺘﺮﺵ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺗﻤﺎﻣﻲ ﻋﺮﺻﻪ ﻫﺎ‪ ،‬ﺗﻌﺠﺐ ﺍﮐﺜﺮ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﻭ‬

‫ﻣﺘﺨﺼﺼﻴﻦ ﺭﺍ ﺑﺎﻋﺚ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺑﻪ ﺍﻋﺘﻘﺎﺩ ﺍﻏﻠﺐ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﻫﻨﻮﺯ ﺩﺭ ﻣﻴﺎﻧﻪ ﺭﺍﻩ ﺑﻮﺩﻩ ﻭ ﻳﮏ‬ ‫ﺍﻧﻘﻼﺏ ﺩﻳﺠﻴﺘﺎﻟﻲ ﮐﺎﻣﻞ ﻭ ﺑﺴﻴﺎﺭ ﻓﺮﺍﮔﻴﺮ ﺭﺍ ﺩﺭ ﺁﻳﻨﺪﻩ ﺷﺎﻫﺪ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪.‬‬ ‫ﻭﺿﻌﻴﺖ ﻓﻌﻠﻲ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺍﻏﻠﺐ ﻣﻮﺍﺭﺩ‪ ،‬ﻣﺸﺎﺑﻪ ﻭﺿﻌﻴﺖ ﻣﺪﻝ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺑﺰﺭﮒ‬

‫)‪ (Mainfarame‬ﺩﺭ ﮔﺬﺷﺘﻪ ﺍﺳﺖ‪ .‬ﺩﺭ ﻗﻴﺎﺱ ﻓﻮﻕ‪ ،‬ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺑﻤﻨﺰﻟﻪ ﺗﺮﻣﻴﻨﺎﻝ ﻫﺎﻱ‬ ‫ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺑﺰﺭﮒ ﺑﻮﺩﻩ ﻭ ﺩﻗﻴﻘﺎ" ﺩﺭ ﻫﻤﺎﻥ ﺭﺍﺳﺘﺎ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺗﻤﺎﻡ ﺍﻃﻼﻋﺎﺕ‬

‫ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺩﺭ ﺑﺎﻧﮏ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺘﻤﺮﮐﺰ ﺷﺪﻩ ﺍﻱ‪ ،‬ﺫﺧﻴﺮﻩ‬ ‫ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺩﺭ ﻫﺮ ﻟﺤﻈﻪ ﻗﺎﺩﺭ ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﺍﺯ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺻﻔﺤﺎﺕ ﻭﺏ‪ ،‬ﺻﺮﻓﺎ" ﺗﺼﻮﻳﺮﻱ ﺍﺯ ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺑﻮﺩﻩ ﻭ ﺩﺍﺩﻩ‬

‫ﻫﺎﻱ ﻭﺍﻗﻌﻲ ﻭ ﺍﺳﺎﺳﻲ ﺭﺍ ﺷﺎﻣﻞ ﻧﻤﻲ ﮔﺮﺩﻧﺪ‪ ) .‬ﺷﺎﻣﻞ ﺧﻮﺩ ﺩﺍﺩﻩ ﻫﺎ ﻧﻤﻲ ﺑﺎﺷﻨﺪ (‪ .‬ﺍﻃﻼﻋﺎﺕ‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭﻳﺎﻓﺖ ﮐﺮﺩ‪ ،‬ﻭﻟﻲ ﺍﻣﮑﺎﻥ ﻭﻳﺮﺍﻳﺶ‪ ،‬ﺗﻔﺴﻴﺮ ﻫﺎﻱ ﺟﺎﻧﺒﻲ‬ ‫ﻭ ﻳﺎ ﺳﺎﻳﺮ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﻔﺎﺭﺷﻲ ﻧﻤﻮﺩﻥ ﺩﺍﺩﻩ ﻫﺎ‪ ،‬ﺍﻣﺮﻱ ﺑﺴﻴﺎﺭ ﻣﺸﮑﻞ ﻭ ﺩﺭ ﺑﺮﺧﻲ‬ ‫ﺣﺎﻻﺕ ﻏﻴﺮﻣﻤﮑﻦ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﺮﺧﻲ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺼﺪ ﺍﺳﺘﺨﺮﺍﺝ ﻭ ﺟﻤﻊ ﺁﻭﺭﻱ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﭼﻨﺪﻳﻦ ﻭﺏ ﺳﺎﻳﺖ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﻧﻬﺎﻳﺖ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬ ‫ﺭﺍ ﺍﺯ ﺻﻔﺤﺎﺕ ﻭﺏ ﻣﺘﻔﺎﻭﺕ ﺍﻧﺘﺨﺎﺏ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺩﺭ ﻳﮏ ﻓﺎﻳﻞ ﺩﻳﮕﺮ ﮐﻪ ﺑﺎ ﻳﮏ ﺍﺩﻳﺘﻮﺭ ﺧﺎﺹ‬

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‫ﻧﻈﻴﺮ ‪ notepad‬ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﻗﺮﺍﺭ ﺩﻫﻨﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﮐﺎﻣﻼ" ﺩﺳﺘﻲ ﺗﻮﺳﻂ‬

‫ﮐﺎﺭﺑﺮﺍﻥ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﻭ ﻋﻤﻼ" ﻳﮏ ﺣﺮﮐﺖ ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺍﻧﺠﺎﻡ ﻧﻤﻲ ﮔﻴﺮﺩ‪" .‬ﺗﻴﻢ‬ ‫ﺑﺮﻧﺮﺯ ﻟﻲ"‪ ،‬ﻣﺒﺘﮑﺮ ﻭﺏ‪ ،‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ﻭﺏ ﺑﺮ ﺧﺎﺻﻴﺖ " ﻣﺤﻴﻂ ﻣﺤﺎﻭﺭﻩ ﺍﻱ " ﺁﻥ ﺗﺎﮐﻴﺪ‬ ‫ﻓﺮﺍﻭﺍﻥ ﺩﺍﺷﺖ‪ .‬ﻭﺿﻌﻴﺖ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺳﺘﺨﺮﺍﺝ ﻭ ﺟﻤﻊ ﺁﻭﺭﻱ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬ ‫ﺍﺯ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ‪ ،‬ﺑﺎ ﺍﻳﺪﻩ ﻣﻄﺮﺡ ﺷﺪﻩ ﻓﻮﻕ ﻓﺎﺻﻠﻪ ﺯﻳﺎﺩﻱ ﺩﺍﺭﺩ‪.‬‬

‫ﺑﻤﻨﻈﻮﺭ ﮔﺬﺭ ﺍﺯ ﻭﺿﻌﻴﺖ ﻓﻌﻠﻲ ﻭﺏ ﻭ ﺍﺭﺗﻘﺎﺀ ﺁﻥ ﺑﻪ ﻣﺤﻴﻄﻲ ﮐﻪ ﺻﺮﻓﺎ" ﻧﻤﺎﻳﺶ ﺩﻫﻨﺪﻩ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺍﻳﺴﺘﺎ ﻧﺒﺎﺷﺪ‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﻧﺴﻞ ﺟﺪﻳﺪﻱ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﮐﻪ ﭘﺎﺳﺨﮕﻮﻱ ﻧﻴﺎﺯ ﻫﺎ ﻭ ﺍﻧﺘﻈﺎﺭﺍﺕ‬

‫ﻓﻌﻠﻲ ﻭ ﻣﺸﮑﻼﺕ ﻣﻮﺟﻮﺩ ﺑﺎﺷﺪ‪ ،‬ﺑﻮﺟﻮﺩ ﺁﻳﺪ‪ .‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﻣﺸﺎﺑﻪ ﺟﺰﺍﻳﺮ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺩﻩ ﮐﻪ ﮔﺮﭼﻪ ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ ﺟﺰﺍﻳﺮ ﻓﻮﻕ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺼﻮﺭﺕ ﭘﻮﻳﺎ ﻧﻴﺰ‬ ‫ﺍﻳﺠﺎﺩ ﮔﺮﺩﺩ‪ ،‬ﻭﻟﻲ ﻫﻴﭽﮕﻮﻧﻪ ﺗﻌﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﺟﺰﺍﻳﺮ ﻓﻮﻕ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪ .‬ﺗﻨﻬﺎ ﺗﻌﺎﻣﻞ‬ ‫ﺍﺭﺗﺒﺎﻃﻲ ﺑﺎ ﺟﺰﺍﻳﺮ ﻓﻮﻕ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﺁﻥ ﺳﺎﻳﺖ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻻﺯﻡ ﺍﺳﺖ ‪،‬‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‪ ،‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻫﻮﺷﻤﻨﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺩﺭ ﻳﮏ ﻫﻤﻴﺎﺭﻱ ﻭ ﻫﻤﮑﺎﺭﻱ‬ ‫ﺗﻌﺮﻳﻒ ﺷﺪﻩ‪ ،‬ﺯﻣﻴﻨﻪ ﺍﺭﺗﺒﺎﻁ ﻭ ﺗﻌﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﻫﺮ ﻳﮏ ﺍﺯ ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﻓﺮﺍﻫﻢ‬ ‫ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﻧﺴﻞ ﻗﺒﻠﻲ ﺍﻳﻨﺘﺮﻧﺖ ﺗﻤﺎﻡ ﺗﻼﺵ ﺩﺭ ﺟﻬﺖ ﺑﻬﺒﻮﺩ ﻧﺤﻮﻩ ﺍﺭﺗﺒﺎﻁ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ ﺻﺮﻑ ﮔﺮﺩﻳﺪ‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺩﺭ ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ ﻻﺯﻡ ﺍﺳﺖ‪ ،‬ﺗﻌﺎﻣﻞ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺟﻮﺩ ﺁﻳﺪ ﻭ ﻓﺼﻞ ﺟﺪﻳﺪﻱ ﺑﺎ ﻧﺎﻡ " ﮔﻔﺘﻤﺎﻥ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ "‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺷﺎﻫﺪ ﺑﺎﺷﻴﻢ‪ ،‬ﺑﺎ ﺣﺮﮐﺖ ﺑﺴﻤﺖ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﺟﺰﺍﻳﺮ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﺰﻭﻟﻪ ﺷﺪﻩ ﺍﺯ ﺣﺎﻟﺖ ﻣﺤﺪﻭﺩ ﺧﻮﺩ ﺧﺎﺭﺝ ﺷﺪﻩ ﻭ ﺑﻴﻦ ﺟﺰﺍﻳﺮ ﻓﻮﻕ ‪ ،‬ﭘﻞ ﻫﺎﻱ‬

‫ﻣﺘﻔﺎﻭﺕ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﺠﺎﺩ ﻭ ﻋﻤﻼ" ﺑﺎ ﺗﺤﻮﻟﻲ ﺷﮕﺮﻑ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪ .‬ﺍﻏﻠﺐ ﺳﺮﻭﻳﺲ ﻫﺎ‬ ‫ﻭ ﺍﻣﮑﺎﻧﺎﺕ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺗﺎﮐﻨﻮﻥ ﺍﺯ ﻃﺮﻳﻖ ﻫﻤﻴﻦ ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﺰﻭﻟﻪ ﺷﺪﻩ ﻗﺮﺍﺭ‬ ‫ﻣﻲ ﮔﺮﻓﺖ‪ ،‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺭﺗﺒﺎﻁ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﻴﻦ ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺩﺳﺘﺎﻭﺭﺩﻫﺎﻱ‬ ‫ﺑﻤﺮﺍﺗﺐ ﮔﺴﺘﺮﺩﻩ ﺗﺮﻱ ﻧﺴﺒﺖ ﺑﻪ ﻭﺿﻌﻴﺖ ﻓﻌﻠﻲ ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫‪ ،(Language Extensible Markup(XML‬ﻫﺴﺘﻪ ﺍﺳﺎﺳﻲ ﮔﺬﺭ ﺍﺯ ﻣﺮﺣﻠﻪ ﻓﻌﻠﻲ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻗﺪﻡ ﮔﺬﺍﺷﺘﻦ ﺩﺭ ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ‪ ، XML .‬ﻳﮏ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺻﻨﻌﺘﻲ ﺍﺭﺍﺋﻪ‬ ‫ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﻨﺴﺮﺳﻴﻮﻡ ﻭﺏ ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎﻱ ﻋﻈﻴﻢ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺭ ﺳﻄﺢ‬

‫ﺩﻧﻴﺎ ﭘﺬﻳﺮﻓﺘﻪ ﺷﺪﻩ ﻭ ﺑﻌﻨﻮﺍﻥ ﻣﺤﻮﺭ ﺗﻮﺳﻌﻪ ﺩﺭ ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻭ ﺍﻫﺘﻤﺎﻡ ﺟﺪﻱ‬ ‫ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، XML‬ﺑﻴﻦ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﻭ ﺧﻮﺩ ﺍﻃﻼﻋﺎﺕ ‪ ،‬ﻳﮏ ﺗﻤﺎﻳﺰ ﻭ‬ ‫ﺗﻔﮑﻴﮏ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪ XML .‬ﺩﺭ ﻣﻮﺍﺭﺩ ﻣﺘﻌﺪﺩ‪ ،‬ﺩﺍﺭﺍﻱ ﻋﻤﻠﮑﺮﺩﻱ ﻣﺸﺎﺑﻪ ‪HTML‬‬

‫ﺍﺳﺖ‪ .‬ﺩﺭ ‪ HTML‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﮓ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ‬

‫ﺗﻌﺮﻳﻒ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ‪ XML‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﮓ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﺳﺎﺧﺘﺎﺭ ﻣﻨﺎﺳﺒﻲ ﺑﺮﺍﻱ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺗﻌﺮﻳﻒ ﻭ ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺍﺩﻩ ﻫﺎ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ‬

‫ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪ ، XML .‬ﺍﻣﮑﺎﻥ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ‪ ،‬ﻭﻳﺮﺍﻳﺶ ﻭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺑﺎ ﺳﺎﻳﺮ ﺳﺎﻳﺖ ﻫﺎ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻭ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻫﺮ ﻳﮏ ﺍﺯ ﺻﻔﺤﺎﺕ‬ ‫ﻭﺏ ﺩﺍﺭﺍﻱ ﻳﮏ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻮﭼﮏ ﺷﺪﻩ ) ﺍﻃﻼﻋﺎﺕ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﺎﺧﺘﺎﺭﻫﺎﻱ ‪ (XML‬ﮐﻪ‬

‫ﺑﺮﺍﺣﺘﻲ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺳﺎﺧﺘﺎﺭ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﺮﺍﻱ ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﺍﺯ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﺩﺭ ﺟﻬﺖ ﻧﻴﻞ ﺑﻪ ﺧﻮﺍﺳﺘﻪ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺎ‬

‫ﺁﮔﺎﻫﻲ ﺍﺯ ﺳﺎﺧﺘﺎﺭ ﺩﺍﺩﻩ ﻫﺎﻱ ﺫﺧﻴﺮﻩ ﺷﺪﻩ )ﺳﺎﺧﺘﻤﺎﻥ ﺩﺍﺩﻩ( ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺕ ﻭ‬

‫ﮔﻮﻧﺎﮔﻮﻧﻲ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻣﺜﻼ" ﺑﺎ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﻗﻴﻤﺖ ﺳﻬﺎﻡ ﺍﺯ ﻭﺏ ﺳﺎﻳﺖ‬

‫ﻣﺮﺑﻮﻃﻪ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺖ ﺧﻮﺩ ﺍﻧﻮﺍﻉ ﺗﺤﻠﻴﻞ ﻫﺎﻱ ﭘﻮﻳﺎ ﻭ ﮔﺰﺍﺭﺷﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﭘﺲ‬ ‫ﺍﺯ ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻻﺯﻡ ‪ ،‬ﺍﺭﺍﺋﻪ ﺩﺍﺩ‪ .‬ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺩﺭ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﺑﺮ ﺭﻭﻱ‬ ‫ﺩﺍﺩﻩ ﻫﺎ) ﺩﺍﺩﻩ ﻫﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺳﺎﺧﺘﺎﺭ ﻣﻨﺎﺳﺐ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ XML‬ﺗﻌﺮﻳﻒ ﻣﻲ ﮔﺮﺩﻧﺪ (‬

‫ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺎ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺩﺭ ﻭﺏ ﺳﺎﻳﺖ ﺩﻳﮕﺮ ﻣﺘﻔﺎﻭﺕ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‬ ‫ﺩﺭ ﺍﺑﺘﺪﺍ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺎﻳﻞ ﻫﺎﻱ ‪ XML‬ﺩﺭﻳﺎﻓﺖ ﻭ ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ‬ ‫ﻻﺯﻡ ﻭ ﺩﻟﺨﻮﺍﻩ‪ ،‬ﺑﺎ ﻓﻮﺭﻣﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ) ﻧﻪ ﺗﺤﻤﻴﻠﻲ ( ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﺳﺎﻳﺖ ﻗﺮﺍﺭ ﺩﺍﺩﻩ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ XML .‬ﺩﺭ ﺳﻨﺎﺭﻳﻮﻱ ﻓﻮﻕ ﺑﻤﻨﺰﻟﻪ ﭘﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺩﻩ ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺮ ﺍﺳﺎﺱ‬ ‫‪29‬‬

‫ﺳﺎﺧﺘﺎﺭ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺎﻳﺮ ﺳﺎﻳﺖ ﻫﺎ )ﻧﻤﺎﻳﻨﺪﮔﺎﻥ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻣﺮﺑﻮﻃﻪ( ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ‬ ‫ﺩﺍﺩ‪.‬‬ ‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، XML‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻗﺎﺩﺭ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ‬

‫ﻳﮑﺪﻳﮕﺮ ﺑﻮﺩﻩ ﻭ ﺿﺮﻭﺭﺗﻲ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺯﺑﺎﻥ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﻭ ﻳﺎ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺧﺎﺹ‬

‫ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎ ﺑﺎ ﺍﻳﺠﺎﺩ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ‬

‫ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﻭ ﺗﻌﺎﻣﻞ ﻫﻮﺷﻤﻨﺪﺍﻧﻪ ﺑﻴﻦ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻃﻼﻋﺎﺕ ﺑﺴﺎﺩﮔﻲ ﺑﻴﻦ‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺣﺮﮐﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ ﻳﮏ ﭘﻼﺕ ﻓﻮﺭﻡ ﺍﺭﺗﺒﺎﻃﻲ ﻭ ﻣﺤﺎﺳﺒﺎﺗﻲ ﻧﻈﻴﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺨﺼﻲ‬

‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﮐﻪ ﺑﺮﺍﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻮﺷﺘﻪ ﻣﻲ ﮔﺮﺩﻧﺪ ) ﻧﻈﻴﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﮐﻪ ﺑﺮﺍﻱ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺨﺼﻲ ﻧﻮﺷﺘﻪ ﻣﻲ ﺷﻮﺩ (‪ ،‬ﺩﺭ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺭﺍ ﺩﺍﺷﺘﻪ‬ ‫ﻭ ﭘﺲ ﺍﺯ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﻭ ﺧﺪﻣﺎﺕ ﺍﺯ ﻳﮑﺪﻳﮕﺮ‪ ،‬ﺑﺎ ﺗﺮﮐﻴﺐ ﻭ ﺗﻮﺯﻳﻊ ﺁﻧﻬﺎ ﺑﺎ ﺍﺷﮑﺎﻝ ﮐﺎﻣﻼ"‬

‫ﺧﺎﺹ ﻭ ﺳﻔﺎﺭﺷﻲ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺁﻧﻬﺎ ﺑﺮﺍﻱ ﻫﺮ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‪ ،‬ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻓﺎﺻﻠﻪ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺨﺼﻲ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺣﺬﻑ ﻭ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﻫﺎﻱ ﭘﻴﺸﺮﻓﺘﻪ ﺍﻱ ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺭﺍ ﺑﺼﻮﺭﺕ ﻣﺤﻠﻲ ﻭ‬ ‫ﻳﺎ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺟﻤﻊ ﺁﻭﺭﻱ ﻭ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬ ‫ﺩﺭ ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ ﻓﺎﺻﻠﻪ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺍﻃﻼﻋﺎﺕ ‪ ، online‬ﺳﺮﻭﻳﺲ ﻫﺎ ﻭ ﺩﺳﺘﮕﺎﻫﻬﺎ‪،‬‬ ‫ﺷﮑﺴﺘﻪ )ﺣﺬﻑ( ﺷﺪﻩ ﻭ ﺍﻧﻘﻼﺑﻲ ﺩﺭ ﺯﻣﻴﻨﻪ ﻧﺤﻮﻩ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺁﻧﻬﺎ ﺭﺍ ﺷﺎﻫﺪ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪ .‬ﺍﻣﺮﻭﺯﻩ‪،‬‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺑﮑﺎﺭﮔﻴﺮﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﺠﺰﺍ ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﺧﻮﺩ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ‪ ،‬ﻧﻮﺷﺘﻦ ﻭ ﻳﺎ ﻭﻳﺮﺍﻳﺶ ﻧﺎﻣﻪ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﻭ ﻳﺎ ﭘﻴﺎﻡ ﻫﺎﻱ‬

‫ﻓﻮﺭﻱ ﻭ ﺳﺎﻳﺮ ﻣﻮﺍﺭﺩ ﺩﻟﺨﻮﺍﻩ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺩﺍﺭﻧﺪ‪ .‬ﺩﺭ ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺑﺎ ﺭﻭﻳﮑﺮﺩﻱ‬ ‫ﮐﺎﻣﻼ" ﻣﺠﺘﻤﻊ ﻭ ﻫﻤﮕﻦ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ‬

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‫ﺍﻳﻨﺘﺮﻓﻴﺲ ) ﺭﺍﺑﻂ( ﻭﺍﺣﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻃﻲ ﺷﻔﺎﻑ ﺑﻴﻦ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺨﺼﻲ ﻭ‬ ‫ﻳﺎ ﺳﺎﻳﺮﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﺍﻳﻦ ﻃﺮﻳﻖ ﺍﻣﮑﺎﻥ ﻣﺸﺎﻫﺪﻩ‪ ،‬ﻭﻳﺮﺍﻳﺶ‪ ،‬ﺯﻣﺎﻧﺒﻨﺪﻱ‪،‬‬ ‫ﺍﺭﺗﺒﺎﻁ ﻭ ﺁﻧﺎﻟﻴﺰ ﺩﺍﺩﻩ ﻫﺎ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﻗﺎﺩﺭﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﺯﻣﺎﻥ ﻣﺘﺒﻮﻉ‬

‫ﺧﻮﺩ ﺑﮑﻤﮏ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺍﻣﺮﻭﺯﻩ ﺗﻌﺪﺍﺩ ﻧﺎﻣﻪ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﮐﻪ ﻫﺮ‬ ‫ﻓﺮﺩ ﺩﺭﻳﺎﻓﺖ ﻭ ﺣﺎﻭﻱ ﻧﻮﺷﺘﻪ ﻫﺎﻱ ﺗﺎﻳﭗ ﺷﺪﻩ ﻭ ﻳﺎ ﺣﺎﺷﻴﻪ ﻧﻮﻳﺴﻲ ﺻﻮﺗﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﺴﻴﺎﺭ‬

‫ﻣﺤﺪﻭﺩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺁﻳﻨﺪﻩ‪ ،‬ﺍﮐﺜﺮ ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻓﻮﺭﻣﺘﻲ ﺑﺠﺰ ﻣﺘﻦ ﻫﺎﻱ ﺗﺎﻳﭗ ﺷﺪﻩ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ﻣﺨﺎﻃﺒﺎﻥ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪.‬‬

‫ﺑﻬﺮﺣﺎﻝ ﻭﺿﻌﻴﺖ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺏ ﺑﺴﺮﻋﺖ ﺩﺭ ﺣﺎﻝ ﺗﻐﻴﻴﺮ ﺍﺳﺖ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺗﺤﺖ ﻭﺏ ﺩﺍﺭﺍﻱ‬

‫ﻣﺴﺌﻮﻟﻴﺘﻲ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﻧﺴﺒﺖ ﺑﻪ ﮔﺬﺷﺘﻪ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺳﻄﺢ ﺍﻧﺘﻈﺎﺭﺍﺕ ﻭ ﺧﻮﺍﺳﺘﻪ ﻫﺎ ﺧﻮﺍﻫﻨﺪ‬ ‫ﺑﻮﺩ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺗﺪﻭﻳﻦ‪ ،‬ﻃﺮﺍﺣﻲ ﻭ ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﺳﺖ‪XML .‬‬

‫ﺳﺘﺎﺭﻩ ﺍﻱ ﺑﻲ ﻓﺮﻭﻍ ﺩﺭ ﺑﻴﻦ ﺗﻤﺎﻡ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﻮﺩﻩ ﮐﻪ ﺑﻌﻨﻮﺍﻥ ﺷﺎﻩ ﮐﻠﻴﺪ ﻃﻼﺋﻲ‬ ‫ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ ، HTML‬ﺩﺭ ﺁﻳﻨﺪﻩ ﺍﻱ ﻧﻪ‬ ‫ﭼﻨﺪﺍﻥ ﺩﻭﺭ ﺑﻪ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ XML‬ﺗﺒﺪﻳﻞ ﺗﺎ ﺑﺘﻮﺍﻧﻨﺪ ﺩﺭ ﺑﻴﻦ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﻭﺏ ﺳﺎﻳﺖ‬

‫ﻣﻮﺟﻮﺩ‪ ،‬ﺯﺑﺎﻧﻲ ﺑﺮﺍﻱ ﮔﻔﺘﻦ ﻭ ﮔﻮﺷﻲ ﺑﺮﺍﻱ ﺷﻨﻴﺪﻥ‪ ،‬ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻭﺏ ﺳﺎﻳﺖ‬

‫ﻫﺎ ﺍﺯ ﺣﺎﻟﺖ ﺍﻳﺰﻭﻟﻪ ﻭ ﻣﺤﺪﻭﺩ ﻭ ﻣﺤﺼﻮﺭ ﺩﺭ ﻳﮏ ﺣﺼﺎﺭ ﻓﻴﺰﻳﮑﻲ ﻭ ﻣﻨﻄﻘﻲ ﺧﺎﺭﺝ ﻭ ﺯﻣﻴﻨﻪ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﺁﻧﻬﺎ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺑﺎﻻﺗﺮﻳﻦ ﺑﻬﺮﻩ ﺭﺍ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺑﺮﺩ‪ .‬ﺁﻧﺎﻥ ﻓﻘﻂ ﺧﻮﺍﺳﺘﻪ ﺧﻮﺩ ﺭﺍ ﻣﻄﺮﺡ ﻭ ﺑﺎ ﺗﻤﻬﻴﺪﺍﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ‪ ،‬ﺩﺭ ﺳﺮﻳﻌﺘﺮﻳﻦ ﺯﻣﺎﻥ‬

‫ﻣﻤﮑﻦ‪ ،‬ﻣﻨﻄﻘﻲ ﺗﺮﻳﻦ ﻭ ﻣﺒﺴﻮﻁ ﺗﺮﻳﻦ ﭘﺎﺳﺦ ﺑﻪ ﺁﻧﻬﺎ ﺍﺭﺍﺋﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ ، .‬ﭘﺎﺳﺨﻲ ﮐﻪ ﺑﺮﺍﻱ‬ ‫ﺑﺪﺳﺖ ﺁﻭﺭﺩﻥ ﺁﻥ‪ ،‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺩﺭ ﺗﻌﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺗﺎ‬

‫ﺑﺘﻮﺍﻧﻨﺪ ﺳﻄﺢ ﺟﺪﻳﺪﻱ ﺍﺯ ﺍﻧﺘﻈﺎﺭﺍﺕ ﻭ ﺧﻮﺍﺳﺘﻪ ﻫﺎ ﺭﺍ ﺗﺤﻘﻖ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻧﺴﻞ ﺟﺪﻳﺪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻣﺴﺘﻠﺰﻡ ﻭﺟﻮﺩ ﺳﺎﻳﺖ ﻫﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﻳﺎﺩ ﮔﺮﻓﺘﻪ ﺍﻧﺪ ﭼﮕﻮﻧﻪ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺍﻭﺩﻩ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺩﺍﺷﺘﻪ ﻭ ﻫﺮ ﺭﻭﺯ ﻧﻴﺰ ﺑﺮ ﺍﻳﻦ ﺗﻮﺍﻥ ﻭ ﭘﺘﺎﻧﺴﻴﻞ ﻧﻴﺰ ﻣﻲ ﺍﻓﺰﺍﻳﻨﺪ‪.‬‬

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‫ﺗﻌﺎﺭﻳﻒ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﺗﺤﺖ ﻭﺏ‬ ‫ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﻭﺏ‪ ،‬ﺍﺯ ﻭﺍﮊﻩ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ Web-based ، Web-enabled :‬ﻭ ‪ Web application‬ﻧﻤﻮﻧﻪ‬ ‫ﻫﺎﺋﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻭﺍﮊﻩ ﻫﺎﻱ ‪ Web-Based‬ﻭ ‪ Web-enabled‬ﺩﺭ ﺑﺮﺧﻲ‬

‫ﻣﻮﺍﺭﺩ ﺑﺠﺎﻱ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺗﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﻭﺏ‪،‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﺍﻧﺖ ﻫﺎ ﺭﺍ ﺗﺸﺮﻳﺢ ﻭ ﻣﺸﺨﺺ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﺩﺳﺘﻴﺎﺑﻲ ﭘﻴﺪﺍ ﮐﺮﺩ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺩﺭ‬

‫ﻣﻮﺍﺭﺩ ﻣﺘﻌﺪﺩﻱ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺘﻔﺎﻭﺕ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻃﺮﺍﺣﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ ) Web-Based‬ﻣﺒﺘﻨﻲ‬ ‫ﺑﺮ ﻭﺏ (‪ ،‬ﺑﮕﻮﻧﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺏ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﺩﺭ‬ ‫ﻣﻘﺎﺑﻞ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ ، Web-enabled‬ﺩﺍﺭﺍﻱ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﺒﺘﻲ ﺑﺮ ﻭﺏ ﺑﻤﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺮﺍﺭﻫﺎﻱ ﻣﻮﺟﻮﺩ ) ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺳﻨﺘﻲ ( ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻓﻮﻕ‬

‫ﻗﺒﻞ ﺍﺯ ﻣﻄﺮﺡ ﺷﺪﻥ ﻭﺏ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻭ ﺑﺎ ﻃﺮﺍﺣﻲ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬ ‫ﺍﻣﮑﺎﻧﺎﺕ ﺁﻧﻬﺎ ﺩﺭ ﺻﻔﺤﺎﺕ ﻭﺏ ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﻃﺮﺍﺣﻲ ﻳﮏ ﻓﺮﻡ ﻻﺯﻡ‪،‬‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺧﺬ ﻭ ﺑﺎ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺑﺎﻧﮏ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻮﺟﻮﺩ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ‬ ‫ﻧﻈﺮ ﺭﺍ ﺍﺳﺘﺨﺮﺍﺝ ﻭ ﻧﺘﺎﻳﺞ ﺭﺍ ﺑﺎ ﻳﮏ ﻓﺮﻣﺖ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﻣﺮﻭﺭﮔﺮ ﺍﺭﺳﺎﻝ ﮐﺮﺩ‪ .‬ﺑﻬﺮﺣﺎﻝ ﺑﺮﻧﺎﻣﻪ‬ ‫ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ‪ ،‬ﺍﺯ ﺁﻏﺎﺯ ﺑﺎ ﺭﻭﻳﮑﺮﺩ ﻭﺏ‪ ،‬ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﺮﻧﺎﻣﻪ‬ ‫ﻫﺎﻱ ‪ ، Web-enabled‬ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﮑﻤﮏ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﺒﺘﻲ ﺑﺮ ﻭﺏ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ ، Web-Based‬ﺩﺍﺭﺍﻱ ﺍﻣﮑﺎﻧﺎﺕ ﻭ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺑﻮﺩﻩ ﮐﻪ ﺑﻤﻨﻈﻮﺭ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﻭﺏ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ ، Web-enabled‬ﺩﺍﺭﺍﻱ ﻳﮏ‬ ‫‪ Gateway‬ﻣﺠﺰﺍ ﺗﺤﺖ ﻭﺏ ﺑﻮﺩﻩ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻗﺪﻳﻤﻲ ﺭﺍ ﻓﺮﺍﻫﻢ‬

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‫ﻣﻲ ﺁﻭﺭﺩ‪ Gateway .‬ﻣﻮﺟﻮﺩ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻤﺎﻡ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻭﺟﻮﺩ ﺭﺍ‬

‫ﻓﺮﺍﻫﻢ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ ﻭ ﺻﺮﻓﺎ" ﭘﺎﺳﺨﮕﻮ ﺑﻪ ﺑﺨﺶ ﻣﺤﺪﻭﺩﻱ ﺍﺯ ﺍﻧﺘﻈﺎﺭﺍﺕ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻬﻲ‬ ‫ﺍﺳﺖ‬ ‫ﺑﺨﺶ ﻫﺎﺋﻲ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﻮﺟﻮﺩ )ﺳﻨﺘﻲ( ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺭﻭﻳﮑﺮﺩ ﻭﺏ ﺑﺎﺯﻧﻮﻳﺴﻲ ﺷﺪﻩ ﺗﺎ‬ ‫ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺁﻧﺎﻥ ﺑﺎ ‪ Gateway‬ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺑﺮﺧﻲ ﺍﺯ ﺳﺎﻳﺖ ﻫﺎ ﻧﻈﻴﺮ‪ :‬ﺧﺮﻳﺪ ﮐﺎﻻ‪ ،‬ﮐﺘﺎﺏ‪ ،‬ﺭﺯﻭ ﺑﻠﻴﻂ ﻫﻮﺍﭘﻴﻤﺎ ‪،‬‬

‫ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ) ﻧﻈﻴﺮ ‪ ( hotmail‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬

‫ﻭﺏ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﺑﺮﺧﻲ ﺗﻌﺎﺭﻳﻒ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺗﺤﺖ ﻭﺏ ﺁﺷﻨﺎ ﻣﻲ ﺷﻮﻳﻢ‪:‬‬ ‫● ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺗﻲ ﺧﺎﺹ ﻧﻈﻴﺮ ﻓﺮﻭﺵ ﮐﺎﻻ ﺍﺳﺖ‪.‬‬ ‫● ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﻭﺏ ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫● ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺩﺭ ﺷﺒﮑﻪ ﺍﺟﺮﺍﺀ ﻭ ﺍﻣﮑﺎﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻲ‬ ‫ﺑﻪ ﭼﻨﺪﻳﻦ ﮐﺎﺭﺑﺮ ﺩﺭ ﻫﺮ ﻟﺤﻈﻪ ﺭﺍ ﺩﺍﺭﺍ ﺍﺳﺖ‪.‬‬ ‫● ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﮐﻪ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ Http‬ﺑﻌﻨﻮﺍﻥ ﻫﺴﺘﻪ ﭘﺮﻭﺗﮑﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺧﻮﺩ ﺑﻤﻨﻈﻮﺭ‬

‫ﺗﻮﺯﻳﻊ ﻭ ﺍﺭﺍﺋﻪ ﺍﻃﻼﻋﺎﺕ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﻭ ﺑﺎ ﻓﺮﻣﺖ ‪ Html‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺁﻧﺎﻥ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﺭﺑﺮﺍﻥ‬ ‫ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫● ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺩﺍﺭﺍﻱ ﻻﻳﻪ ﻫﺎﻱ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫▪ ﻳﮏ ﻻﻳﻪ ﻧﺎﺯﮎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ) ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ (‬ ‫▪ ﻳﮏ ﻻﻳﻪ ﻧﻤﺎﻳﺶ ﻭ ﺍﺭﺍﺋﻪ ) ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ (‬ ‫▪ ﻳﮏ ﻻﻳﻪ ‪ ) Application‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪(Application‬‬ ‫‪33‬‬

‫▪ ﻳﮏ ﻻﻳﻪ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﺍﺭﺍﺋﻪ ﻳﮏ ﻣﺪﻝ ﻫﻤﮕﺮﺍ ﻭ ﺟﺎﻣﻊ‬ ‫ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺗﺤﺖ ﻭﺏ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻭ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ‬ ‫ﮔﺮﺩﺩ‪ .‬ﺑﻤﻨﻈﻮﺭ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺻﺮﻓﺎ" ﻳﮏ ﺭﻭﺵ ﻭﺟﻮﺩ‬ ‫ﻧﺪﺍﺷﺘﻪ ﻭ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﮐﻪ ﻫﺮ ﻳﮏ ﺑﺮﺧﺎﺳﺘﻪ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ ‪ ،‬ﺑﻪ ﻫﺪﻑ ﺧﻮﺩ ﺩﺳﺖ ﭘﻴﺪﺍ ﮐﺮﺩ‪.‬‬

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‫ﺑﺮﺧﻲ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﻣﺘﻌﻠﻖ ﺑﻪ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﻮﺩﻩ ﮐﻪ ﺩﺭ‬ ‫ﺣﺎﻻﺗﻲ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺍﺭﺍﻱ ﻋﻤﻠﮑﺮﺩﻫﺎﻱ ﻣﺸﺎﺑﻪ ﺑﺎﺷﻨﺪ‪ .‬ﮐﻨﺴﺮﺳﻴﻮﻡ ﻭﺏ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺳﺘﺎﻧﺪﺍﺭ‬ ‫ﻧﻤﻮﺩﻥ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﭘﺲ ﺍﺯ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻧﻤﻮﺩﻥ ﻫﺮ ﻳﮏ‬ ‫ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ‪ ،‬ﺗﻤﺎﻡ ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻭ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺳﻌﻲ ﺩﺭ ﺭﻋﺎﻳﺖ‬ ‫ﻣﻮﺍﺭﺩ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺷﺪﻩ ﮐﺮﺩﻩ ﺗﺎ ﺑﺪﻳﻦ ﻃﺮﻳﻖ ﻣﺨﺎﻃﺒﺎﻥ ﺑﻴﺸﺘﺮﻱ ﺭﺍ ﺟﺬﺏ ﻭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻭﺳﻴﻊ‬ ‫ﺗﺮ ﻭ ﮔﺴﺘﺮﺩﻩ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬

‫ﻋﻤﻠﮑﺮﺩ ﺍﮐﺜﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺗﺤﺖ ﻭﺏ ﺩﺭ ﻣﻮﺍﺭﺩ ﺑﺴﻴﺎﺭﻱ ﻣﺸﺎﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺖ‪:‬‬ ‫ﺍﺭﺍﺋﻪ ﻳﮏ ﺑﺨﺶ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﮐﺎﺭﺑﺮﺍﻥ ‪ :‬ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﺳﺘﻪ ﻫﺎ ﻭ ﻳﺎ ﻧﻤﺎﻳﺶ‬ ‫ﻧﺘﺎﻳﺞ‬ ‫ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺩﺭﺧﻮﺍﺳﺖ ﮐﺎﺭﺑﺮﺍﻥ ) ﺍﺯ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﺴﻤﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ (‬ ‫ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻻﺯﻡ ) ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ (‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻊ ﺩﺍﺩﻩ ﺋﻲ ) ﺑﺎﻧﮏ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ( ﻭ ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻻﺯﻡ‬ ‫ﺍﺭﺳﺎﻝ ﻧﺘﺎﻳﺞ ﺑﺪﺳﺘﺖ ﺁﻣﺪﻩ ﺍﺯ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‬ ‫ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻻﺯﻡ ) ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ (‬

‫ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

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‫ﻫﺪﻑ ﺍﺭﺍﺋﻪ ﻳﮏ ﻣﺪﻝ ﻋﻤﻠﻴﺎﺗﻲ ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ‬

‫ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﻣﺪﻝ ﭘﻴﺸﻨﻬﺎﺩﻱ‪ ،‬ﻣﺴﺘﻘﻞ ﺍﺯ ﻧﻮﻉ ﺗﮑﻨﻮﻟﻮﮊﻱ‪ ،‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ ﺻﺮﻓﻨﻈﺮ‬ ‫ﺍﺯ ﻧﻮﻉ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺗﻤﺎﻣﻲ ﻋﻤﻠﻴﺎﺗﻲ ﺭﺍ ﮐﻪ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ ﺭﺍ ﺩﺭ ﭼﻬﺎﺭ ﻻﻳﻪ ﻣﺘﻔﺎﻭﺕ ﺗﺒﻴﻦ ﻭ ﺗﻌﺮﻳﻒ ﮐﺮﺩ‪.‬‬ ‫ﻻﻳﻪ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ‬ ‫ﻻﻳﻪ ﺍﺭﺗﺒﺎﻃﻲ‬ ‫ﻻﻳﻪ ﻣﻴﺎﻧﻲ‬ ‫ﻻﻳﻪ ﺩﺍﺩﻩ‬

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‫ﻫﺮ ﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ ﻓﻮﻕ ﻣﺴﺌﻮﻟﻴﺖ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﻭ ﺩﺭ ﺍﻳﻦ‬ ‫ﺭﺍﺳﺘﺎ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‪ ،‬ﺟﺎﻳﮕﺎﻩ ﻫﺮ ﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ‬

‫ﻓﻮﻕ ﺩﺭ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺗﺸﺮﻳﺢ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺗﺒﻴﻦ ﺟﺎﻳﮕﺎﻩ ﻫﺮ ﻳﮏ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ‬ ‫ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭﻻﻳﻪ ﻫﺎ‪ ،‬ﭘﺮﺩﺍﺧﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﻋﻤﻠﮑﺮﺩ ﻫﺮ ﻻﻳﻪ ﻭ ﺷﻨﺎﺧﺖ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﺯﻣﻴﻨﻪ ﺷﻨﺎﺧﺖ ﺍﺻﻮﻟﻲ‪،‬‬ ‫ﻣﻨﻄﻘﻲ ﻭ ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺭﺍ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺁﻭﺭﺩ‪ .‬ﺩﺍﻣﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺑﺮﺧﻲ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎ ﺻﺮﻓﺎ" ﺩﺭ ﺣﺪ ﻭ ﺍﻧﺪﺍﺯﻩ ﻳﮏ ﻻﻳﻪ ﺑﻮﺩﻩ ﻭ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎ‬ ‫ﺩﺍﺭﺍﻱ ﻋﻤﺎﮐﺮﺩﻱ ﻓﺮﺍ ﻻﻳﻪ ﺍﻱ ﺑﻮﺩﻩ ﻭ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺭ ﭼﻨﺪﻳﻦ ﻻﻳﻪ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻻﻳﻪ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ‬ ‫ﻻﻳﻪ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﺑﺨﺸﻲ ﺍﺯ ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺑﻮﺩﻩ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﮐﺎﺭﺑﺮﺍﻥ ﺭﺍ‬

‫ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻻﻳﻪ ﻓﻮﻕ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬ ‫ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻭ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻻﻳﻪ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺯﻳﺮ‬ ‫ﺍﺳﺖ ‪:‬‬ ‫ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺑﻴﻦ ﺩﻧﻴﺎﻱ ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺩﻧﻴﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺖ‪.‬‬

‫ﺑﺨﺶ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺮﻭﺭﮔﺮ‪ ،‬ﺍﺭﺍﺋﻪ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺗﻤﺎﻡ ﺑﺤﺚ ﻫﺎ ﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﻻﻳﻪ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ‪ ،‬ﺑﺎ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺁﻏﺎﺯ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺗﻮﺳﻂ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺩﺍﺭﺍﻱ ﺍﻣﮑﺎﻧﺎﺕ ﻻﺯﻡ ﺑﺮﺍﻱ ﺗﻔﺴﻴﺮ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﻭ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ‬ ‫ﺁﻧﺎﻥ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﻡ ﻫﺎﻱ ﻭﺏ ﺍﻣﮑﺎﻥ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺍﺭﺳﺎﻝ‬ ‫ﺁﻧﻬﺎ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﻧﺪ‪.‬‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﭘﺲ ﺍﺯ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﻻﺯﻡ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺘﺪﻫﺎﻱ ‪ GET‬ﻭ‬ ‫ﻳﺎ ‪ POST‬ﭘﺮﻭﺗﮑﻞ ‪ ،HTTP‬ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺑﻤﻨﻈﻮﺭ ﭘﺸﺘﻴﺎﻧﻲ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﻭﺿﻌﻴﺖ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺍﺯ ﮐﻮﮐﻲ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻭﺍﺑﺴﺘﻪ ﺑﻪ ﻧﻮﻉ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻣﻤﮑﻦ ﺍﺳﺖ‬ ‫ﺑﺮﺧﻲ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎ ﺗﻮﺳﻂ ﺑﺮﺧﻲ ﺍﺯ ﻣﺮﻭﺭﮔﺮﻫﺎ ﺣﻤﺎﻳﺖ ﻧﺸﺪﻩ ﻭ ﻳﺎ ﺑﺮﺧﻲ ﺍﺯ‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎ ﺍﺯ ﻳﮏ ﻧﺴﺨﻪ ﺧﺎﺹ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﭘﻴﺶ ﺑﻴﻨﻲ ﺷﺪﻩ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺟﺎﻳﮕﺎﻩ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ‬ ‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﻳﮑﻲ ﺍﺯ ﺷﺎﻫﮑﺎﺭﻫﺎﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻮﺩﻩ ﮐﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ‬

‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎ ﻭ ﻣﺸﺎﻫﺪﻩ ﺻﻔﺤﺎﺕ ﻭﺏ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﺍﺯ‬

‫ﺟﺎﻳﮕﺎﻩ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ﺗﺤﺖ ﻭﺏ ﺩﺍﺭﺍﻱ ﻧﻘﺶ ﺑﺴﻴﺎﺭ ﻣﻬﻤﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﺎﻥ ﻭﺏ‬ ‫ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺑﺨﺶ ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺧﻮﺩ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﮔﺴﺘﺮﺩﻩ ﺍﻳﻦ ﻧﻮﻉ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺗﻌﺎﺭﻳﻒ ﻣﺘﻔﺎﻭﺕ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ‪:‬‬ ‫ﻣﺮﻭﺭﮔﺮ ﻭﺏ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ‬ ‫ﺍﻃﻼﻉ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﺭﺳﺎﻧﺪﻩ ﻭ ﭘﺲ ﺍﺯ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺁﻧﻬﺎ ﺭﺍ ﺑﺎ ﻳﮏ ﻓﺮﻣﺖ‬ ‫ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﺻﻔﺤﺎﺕ ﻧﻤﺎﻳﺸﮕﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﻧﻤﺎﻳﺶ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬ ‫ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﻭﺏ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﻣﺘﻘﺎﺿﻲ ﺻﻔﺤﺎﺕ ﻭﺏ‪ ،‬ﺍﻣﮑﺎﻥ ﻣﺸﺎﻫﺪﻩ‬ ‫ﺻﻔﺤﺎﺕ ﻭ ﺧﻮﺍﻧﺪﻥ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪Internet‬‬

‫‪ (IE(Explorer‬ﻭ ‪ Navigator Netscape‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺑﻤﻨﻈﻮﺭ ﻣﺸﺎﻫﺪﻩ ﺻﻔﺤﺎﺕ ﻭﺏ ﻣﺮﺑﻮﻁ ﺑﻪ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ‪ ،‬ﺍﺯ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ‬ ‫ﺗﻮﺳﻂ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﻭ ﻣﺸﺎﻫﺪﻩ ﺁﻧﺎﻥ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫‪39‬‬

‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﺍﻣﮑﺎﻥ ﻣﺸﺎﻫﺪﻩ ﺻﻔﺤﺎﺕ‬ ‫ﻭﺏ‪ ،‬ﺍﺧﺬ ﻓﺎﻳﻞ ﻭ ﺳﺎﻳﺮ ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺩﺭ ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﻓﺮﺍﻫﻢ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻣﺮﻭﺭﮔﺮﻫﺎ ‪ ،‬ﺻﻔﺤﺎﺕ ﻭﺏ ﺭﺍ ﮐﻪ ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺧﻮﺍﻧﺪﻩ ﻭ ﭘﺲ‬ ‫ﺍﺯ ﺗﻔﺴﻴﺮ ﮐﺪﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﺯﻣﻴﻨﻪ ﻧﻤﺎﻳﺶ ﻣﺤﺘﻮﻳﺎﺕ ﻭ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ‬ ‫ﺁﻭﺭﻧﺪ‪.‬‬

‫ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﻋﻼﻭﻩ ﺑﺮ ﺍﻣﮑﺎﻥ ﺗﻔﺴﻴﺮ ﺗﮓ ﻫﺎﻱ ‪ Html‬ﺑﻤﻨﻈﻮﺭ ﺗﺒﻴﻦ ﻧﺤﻮﻩ ﻧﻤﺎﻳﺶ‪ ،‬ﺩﺍﺭﺍﻱ‬ ‫ﻋﻨﺎﺻﺮ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ ﺗﻔﺴﻴﺮ ﺍﺳﮑﺮﻳﭙﺖ ﻫﺎﻱ ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﺑﺎ ﻳﮑﻲ ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ ﺍﺳﮑﺮﻳﭙﺖ ﻧﻴﺰ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺟﺎﻭﺍ ﺍﺳﮑﺮﻳﭙﺖ ﻭ ‪ VBscript‬ﺩﻭ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ ﺍﺯ ﺯﺑﺎﻧﻬﺎﻱ ﺍﺳﮑﺮﻳﭙﺖ ﺑﻮﺩﻩ ﮐﻪ ﺩﺭ ﺍﮐﺜﺮ‬ ‫ﺻﻔﺤﺎﺕ ﭘﻮﻳﺎ ﺩﺍﺭﺍﻱ ﺣﻀﻮﺭﻱ ﻓﻌﺎﻝ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻧﮕﺮﺵ ﮐﺎﺭﺑﺮﺍﻥ ﻣﻌﻤﻮﻟﻲ ﻭ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﺎﻥ ﻭﺏ ﺑﻪ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﮐﺎﻣﻼ" ﻣﺘﻤﺎﻳﺰ ﺑﻮﺩﻩ‬ ‫ﻭ ﻫﺮ ﻳﮏ ﺑﺎ ﺗﻮﺟﻪ ﻧﻮﻉ ﺧﻮﺍﺳﺘﻪ ﻭ ﺍﻧﺘﻈﺎﺭ ﺧﻮﺩ ﺍﺯ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬

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‫ﻣﺮﻭﺭﮔﺮ ‪InterNet Explorer‬‬

‫ﻣﺮﻭﺭﮔﺮ ‪Netscape Communicator‬‬

‫ﻣﺮﻭﺭﮔﺮﻫﺎ ﺭﻭﻧﺪ ﺗﮑﺎﻣﻞ ﻭ ﺷﮑﻞ ﮔﻴﺮﻱ‬ ‫ﻃﺮﺍﺣﻲ‪ ،‬ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻭ ﺗﻮﺳﻌﻪ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻣﻄﺮﺡ ﺷﺪﻥ ﻭﺏ‪ ،‬ﺁﻏﺎﺯ ﻭ‬ ‫ﻫﻤﭽﻨﺎﻥ ﺍﺩﺍﻣﻪ ﺩﺍﺭﺩ‬ ‫‪41‬‬

‫‪.‬‬ ‫‪ . WorldWideWeb‬ﺍﻳﻦ ﻣﺮﻭﺭﮔﺮ ﺗﻮﺳﻂ " ﺗﻴﻢ‪ .‬ﺑﺮﻧﺮﺯ ﻟﻲ " ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٠‬ﻭ ﺑﺮ‬ ‫ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ NeXT‬ﺩﺭ ‪ CERN‬ﻧﻮﺷﺘﻪ ﮔﺮﺩﻳﺪ‪.‬‬ ‫‪" . libwww‬ﺗﻴﻢ‪.‬ﺑﺮﻧﺮﺯ ﻟﻲ " ﻭ ﺩﺍﻧﺸﺠﻮﺋﻲ ﺑﺎ ﻧﺎﻡ " ‪ "Jean-Francois Groff‬ﺍﺯ‬ ‫‪ CERN‬ﺩﺭ ﺳﺎﻝ ‪ ،١٩٩٢‬ﻣﺮﻭﺭﮔﺮ ‪ WorldWideWeb‬ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﺑﺎﻥ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﻲ ‪ C‬ﺑﺎﺯﻧﻮﻳﺴﻲ ﻧﻤﻮﺩﻧﺪ‪.‬‬ ‫‪ . Line-Mode‬ﺩﺍﻧﺸﺠﻮﺋﻲ ﺑﺎ ﻧﺎﻡ "‪ "Nicola pellow‬ﺍﺯ ﺩﺍﻧﺸﺠﻮﻳﺎﻥ ﺭﻳﺎﺿﻲ‬ ‫‪ CERN‬ﺩﺭ ﺳﺎﻝ ‪ ، ١٩٩١‬ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﺧﻄﻲ ﻃﺮﺍﺣﻲ ﻧﻤﻮﺩ ﮐﻪ ﻗﺎﺑﻠﻴﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺮ‬

‫ﺭﻭﻱ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻌﺪﺩ ﺭﺍ ﺩﺍﺷﺖ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ "ﻧﻴﮑﻼ" ﻭ ﺩﺳﺘﻴﺎﺭﺍﻧﺶ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺘﻨﻮﻋﻲ )ﺍﺯ ﻳﻮﻧﻴﮑﺲ ﺗﺎ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ‪(DOS‬‬ ‫ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻧﺪ‪.‬‬ ‫‪ . ViolaWWW‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٢‬ﺗﻮﺳﻂ ﺩﺍﻧﺸﺠﻮﺋﻲ ﺑﺎ ﻧﺎﻡ "‪ "Pei Wei‬ﺍﺯ ﺩﺍﻧﺸﮕﺎﻩ‬ ‫ﺑﺮﮐﻠﻲ ﮐﺎﻟﻴﻔﺮﻧﻴﺎ ‪ ،‬ﺩﻭﻣﻴﻦ ﻣﺮﻭﺭﮔﺮ ﺑﺮﺍﻱ ﻳﻮﻧﻴﮑﺲ ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪ‪.‬‬ ‫‪ . Midas‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٢‬ﺗﻮﺳﻂ "‪ "Tony Johnson‬ﺩﺭ ‪ ،SLAC‬ﺳﻮﻣﻴﻦ ﻣﺮﻭﺭﮔﺮ‬ ‫ﺑﺮﺍﻱ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻳﻮﻧﻴﮑﺲ ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﻫﺪﻑ ﺍﺯ ﻃﺮﺍﺣﻲ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ‬ ‫ﺟﻤﻊ ﺁﻭﺭﻱ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺤﻘﻴﻘﺎﺕ ﻓﻴﺰﻳﮏ ﺑﻮﺩ‪.‬‬ ‫‪ . Samba‬ﺍﻭﻟﻴﻦ ﻣﺮﻭﺭﮔﺮ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﮑﻴﻨﺘﺎﺵ ﮐﻪ ﺗﻮﺳﻂ " ‪Robert‬‬ ‫‪ "Cailliau‬ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﮔﺮﺩﻳﺪ‪.‬ﻧﺴﺨﻪ ﻧﻬﺎﺋﻲ ﻭ ﻋﻤﻠﻴﺎﺗﻲ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ‬ ‫ﺍﻭﺍﺧﺮ ﺳﺎﻝ ‪ ١٩٩٢‬ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪.‬‬

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‫ﻣﻮﺯﺍﺋﻴﮏ ‪ .‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺗﻮﺳﻂ "‪ "Andreessen Marc‬ﻭ "‪ "Eric Bina‬ﺍﺯ ‪NCSA‬‬ ‫ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٣‬ﺑﺮﺍﻱ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ X-Windows‬ﻭ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻳﻮﻧﻴﮑﺲ ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪ .‬ﭼﻨﺪ ﻣﺎﻩ ﺑﻌﺪ ﻧﺴﺨﻪ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺑﻤﻨﻈﻮﺭ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﺳﻴﺴﺘﻢ‬

‫ﻫﺎﻱ ﻣﮑﻴﻨﺘﺎﺵ ﺗﻮﺳﻂ "‪ "Aleks Totic‬ﻃﺮﺍﺣﻲ ﻭ ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪ .‬ﻣﻮﺯﺍﺋﻴﮏ‪ ،‬ﺍﻭﻟﻴﻦ‬ ‫ﻣﺮﻭﺭﮔﺮﻱ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺮ ﺭﻭﻱ ﭘﻼﺕ ﻓﻮﺭﻡ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺑﻮﺩ‪ .‬ﺍﻳﻦ ﻣﺮﻭﺭﮔﺮ ﺩﺍﺭﺍﻱ‬ ‫ﺍﻣﮑﺎﻧﺎﺕ ﻣﺘﻌﺪﺩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺻﻮﺕ‪ ،‬ﺗﺼﻮﻳﺮ‪ ،‬ﻓﺎﻳﻞ ﻫﺎﻱ ﺳﻮﺍﺑﻖ ﻭ ‪ ...‬ﺑﻮﺩ‪ .‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ‬

‫ﭘﺲ ﺍﺯ ﻣﺪﺕ ﺯﻣﺎﻥ ﮐﻮﺗﺎﻫﻲ ﺑﻌﻨﻮﺍﻥ ﺭﺍﻳﺞ ﺗﺮﻳﻦ ﻣﺮﻭﺭﮔﺮ ﻏﻴﺮ ﺍﻗﺘﺼﺎﺩﻱ ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ‬ ‫ﺍﮔﻮﺳﺖ ﺳﺎﻝ ‪ NCSA ، ١٩٩٤‬ﺣﻖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﺷﺮﮐﺖ ‪Spyglass‬‬

‫ﻭﺍﮔﺬﺍﺭ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺷﺮﮐﺖ ﻓﻮﻕ ‪ ،‬ﺍﻣﺘﻴﺎﺯ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺮﻭﺭﮔﺮ ﻣﻮﺯﺍﺋﻴﮏ ﺭﺍ ﺑﻪ ﺷﺮﮐﺖ‬

‫ﻫﺎﻱ ﺩﻳﮕﺮ ﻧﻈﻴﺮ ﻣﺎﮐﺮﻭﺳﺎﻓﺖ ﻭﺍﮔﺬﺍﺭ ﮐﺮﺩ‪ NCSA .‬ﻋﻤﻠﻴﺎﺕ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻭ ﺗﻮﺳﻌﻪ‬ ‫ﻣﺮﻭﺭﮔﺮ ﻣﻮﺯﺍﺋﻴﮏ ﺭﺍ ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٧‬ﻣﺘﻮﻗﻒ ﮐﺮﺩ‪.‬‬ ‫‪ . Arena‬ﺩﺭ ﺳﺎﻝ ‪ "Dave Raggett" ،١٩٩٣‬ﺩﺭ ﻫﻴﻮﻟﺖ ﭘﺎﮐﺎﺭﺩ )‪ (HP‬ﺷﻬﺮ‬ ‫ﺑﺮﻳﺴﺘﻮﻝ ﺍﻧﮕﻠﺴﺘﺎﻥ‪ ،‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺭﺍ ﻃﺮﺍﺣﻲ ﻭ ﻋﺮﺿﻪ ﻧﻤﻮﺩ‪ .‬ﺍﻳﻦ ﻣﺮﻭﺭﮔﺮ ﺩﺍﺭﺍﻱ‬

‫ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻓﺮﺍﻭﺍﻧﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺟﺪﺍﻭﻝ ﻭ ﮔﺮﺍﻓﻴﮏ ﺑﻮﺩ‪.‬‬ ‫‪ . Lynx‬ﺩﺍﻧﺸﮕﺎﻩ ﮐﺎﻧﺰﺍﺱ ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﻣﺴﺘﻘﻞ ﺑﺮﺍﻱ ﻭﺏ ﺭﺍ ﻃﺮﺍﺣﻲ ﻧﻤﻮﺩ‪ .‬ﻫﺪﻑ ﺍﺯ‬ ‫ﻃﺮﺍﺣﻲ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺩﺍﻧﺸﮕﺎﻩ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻭ ﺩﺭ ﺳﺎﻝ ‪،١٩٩٣‬‬ ‫ﺩﺍﻧﺸﺠﻮﺋﻲ ﺑﺎ ﻧﺎﻡ "‪ "Lou Montulli‬ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺴﻲ ﺍﻳﻨﺘﺮﻧﺘﻲ ﺑﻪ ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ﺍﺿﺎﻓﻪ‬

‫ﻭ ﻧﺴﺨﻪ ﺷﻤﺎﺭﻩ ﺩﻭ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ‪ Lynx‬ﺭﺍ ﻋﺮﺿﻪ ﻧﻤﻮﺩ‪ .‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺑﺴﺮﻋﺖ‬ ‫ﻣﺘﺪﺍﻭﻝ ﻭ ﺑﻌﻨﻮﺍﻥ ﮔﺰﻳﻨﻪ ﺍﻱ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﺗﺮﻣﻴﻨﺎﻝ ﻫﺎﻱ ﻓﺎﻗﺪ ﺍﻣﮑﺎﻧﺎﺕ ﮔﺮﺍﻓﻴﮑﻲ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻭ ﻫﻤﭽﻨﺎﻥ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺍﺯ ﺁﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫‪ . Opera‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٤‬ﺗﻮﺳﻂ ﻋﺪﻩ ﺍﻱ ﺍﺯ ﻣﺤﻘﻘﻴﻦ ﻳﮏ ﺷﺮﮐﺖ‬

‫ﻣﺨﺎﺑﺮﺍﺗﻲ ﺩﺭ ﺍﺳﻠﻮ ﻧﺮﻭﮊ‪ ،‬ﺑﺎ ﻧﺎﻡ ‪ Telenor‬ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺳﺎﻝ ﻫﺎﻱ ﺑﻌﺪ ﺩﻭ ﺗﻦ‬ ‫ﺍﺯ ﺍﻋﻀﺎﻱ ﮔﺮﻭﻩ ﻓﻮﻕ ‪ ،‬ﺍﺯ ‪ Telenor‬ﺟﺪﺍ ﺷﺪﻩ ﻭ ﺷﺮﮐﺖ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ‪ Opera‬ﺭﺍ ﺑﺎ‬ ‫ﻫﺪﻑ ﺗﻮﻟﻴﺪ ﺗﺠﺎﺭﻱ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ‪ ،‬ﺗﺎﺳﻴﺲ ﮐﺮﺩﻧﺪ‪ .‬ﻧﺴﺨﻪ ‪ Oper 2.1‬ﺩﺭ ﺳﺎﻝ‬ ‫‪ ١٩٩٦‬ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻋﻤﻮﻡ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪.‬‬

‫‪ . InterNet In A Box‬ﺩﺭ ﺳﺎﻝ ‪ O'Reilly ،١٩٩٤‬ﻭ ﻣﺘﺤﺪﺍﻧﺶ‪ ،‬ﻣﺤﺼﻮﻝ ﻓﻮﻕ ﺭﺍ‬ ‫ﻋﺮﺿﻪ ﻧﻤﻮﺩﻧﺪ‪ .‬ﻣﺤﺼﻮﻝ ﻓﻮﻕ ﺷﺎﻣﻞ ﺗﻤﺎﻣﻲ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺿﺮﻭﺭﻱ ﻭ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﻧﺼﺐ ﺻﺮﻓﺎ" ﻳﮏ‬

‫ﺑﺮﻧﺎﻣﻪ ﺍﺯ ﻧﺼﺐ ﻭ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﻣﮑﺎﻧﺎﺕ‬ ‫ﻣﻮﺟﻮﺩ ﺑﻲ ﻧﻴﺎﺯ ﻣﻲ ﺷﺪﻧﺪ‪.‬‬

‫‪ . Mozilla‬ﺩﺭ ﺍﮐﺘﺒﺮ ﺳﺎﻝ ‪ ، ١٩٩٤‬ﺷﺮﮐﺖ ﻧﺖ ﺍﺳﮑﻴﭗ ‪ ،‬ﺍﻭﻟﻴﻦ ﻧﺴﺨﻪ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ ﺭﺍ‬ ‫ﺑﺎ ﻧﺎﻡ ‪ Mozilla 0.96b‬ﻋﺮﺿﻪ ﻧﻤﻮﺩﻧﺪ‪ ) .‬ﻧﺴﺨﻪ ﻓﻮﻕ ﻧﺴﺨﻪ ﺑﺘﺎ ﺑﻮﺩ (‪ .‬ﺩﺭ ﺩﺳﺎﻣﺒﺮ‬

‫ﻫﻤﺎﻥ ﺳﺎﻝ ‪،‬ﻧﺴﺨﻪ ﻧﻬﺎﺋﻲ ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺑﺎ ﻧﺎﻡ ‪ ١,٠ Mozilla‬ﻋﺮﺿﻊ ﮔﺮﺩﻳﺪ‪ .‬ﻣﺮﻭﺭﮔﺮ‬

‫ﻓﻮﻕ ﺍﻭﻟﻴﻦ ﻣﺮﻭﺭﮔﺮ ﺗﺠﺎﺭﻱ ﺩﺭ ﻋﺮﺻﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ ‪.‬‬ ‫‪ . Internet Explorer‬ﺩﺭ ﺍﮔﻮﺳﺖ ﺳﺎﻝ ‪ ،١٩٩٥‬ﺷﺮﮐﺖ ﻣﺎﮐﺮﻭﺳﺎﻓﺖ ﻫﻤﺰﻣﺎﻥ ﺑﺎ‬ ‫ﻣﻌﺮﻓﻲ ﻭﻳﻨﺪﻭﺯ ‪ ، ٩٥‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺭﺍ ﻋﺮﺿﻪ ﻧﻤﻮﺩ‪ .‬ﻣﺮﻭﺭﮔﺮ ﻓﻮﻕ ﺑﻬﻤﺮﺍﻩ ﻣﺮﻭﺭﮔﺮ‬ ‫ﺷﺮﮐﺖ ﻧﺖ ﺍﺳﮑﻴﭗ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻧﻮﻉ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﺍﮐﺜﺮ ﮐﺎﺭﺑﺮﺍﻥ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫● ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﺷﺎﻣﻞ ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎﺋﻲ ﺍﺯ ﻃﺮﻑ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻭﺏ ﺑﺮﺍﻱ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺮﻭﺭﮔﺮﻫﺎ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺩﺭﺧﻮﺍﺳﺖ ﺧﻮﺩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ‬

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‫ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻭﺍﮊﻩ "ﻣﺮﻭﺭﮔﺮ " ﺑﺮﺍﻱ‬.‫ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‬Http ‫ ﭼﺮﺍﮐﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﻋﻼﻭﻩ ﺑﺮ‬، ‫ﺍﻳﻦ ﻧﻮﻉ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎ ﭼﻨﺪﺍﻥ ﻣﻨﻄﻘﻲ ﺑﻨﻈﺮ ﻧﻤﻲ ﺭﺳﺪ‬ ‫ ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻭ ﻓﺮﺍﻭﺍﻧﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺮﻧﺎﻣﻪ‬، ‫ﺍﻣﮑﺎﻥ ﺑﺎﺯﻳﺎﺑﻲ ﻭ ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ‬

.‫ﻧﻮﻳﺴﻲ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﺏ ﻣﻲ ﺑﺎﺷﻨﺪ‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﻤﻨﺰﻟﻪ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﭘﺮﺩﺍﺯﺵ ﻭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺕ‬

‫ ﺑﺮﻧﺎﻣﻪ ﻧﻮﻳﺴﺎﻥ ﻭﺏ ﺑﺪﻭﻥ ﺷﻨﺎﺧﺖ ﻭ ﺗﻮﺟﻪ ﺑﻪ ﭘﺘﺎﻧﺴﻴﻞ ﻭ ﺍﻣﮑﺎﻧﺎﺕ‬.‫ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‬

.‫ ﺧﻮﺩ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‬،‫ ﻗﺎﺩﺭ ﺑﻪ ﺁﻓﺮﻳﻨﺶ ﺁﺛﺎﺭ ﻣﺎﻧﺪﮔﺎﺭ‬،‫ﻣﺮﻭﺭﮔﺮﻫﺎ‬ ‫ﻣﻘﺎﻳﺴﻪ ﺍﻣﮑﺎﻧﺎﺕ ﻣﺮﻭﺭﮔﺮﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ‬ Windows Table XML color n n n n y y s y n y n y n n n n n n n n y y n y n y n y n n n n y y n y n y n n Macintosh Table XML color n n n n

I frames n n y y y y n n n n n n n n n n n n n n

java script N N Y Y Y Y N N N N Y Y Y Y S N Y Y Y N

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45

tablesframes javabrowsers y n y y y y y y y n y y y y y y y y y y

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AOL 3.0 AOL 1.0 IE 5.5 IE 5.0 IE 4.0 IE 3.0 IE 2.0 IE 1.0 Mosaic 3.0 Mosaic 1.0 NS 6 NS 4.7 NS 4.5 NS 3.0 NS 2.0 NS 1.1 Opera 4.2 Opera 3.60 Opera 3.5 Lynx

n y n y n n n n Unix Table XML color y y n y n n n n y y n y n n n n n n n n n n Linux Table XML color y y y y n n y y y y n n Television Table XML color n y NextStep Table XML color

n n n n

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46

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‫ﺯﻳﺮ ﺳﺎﺧﺖ ﺍﻳﻨﺘﺮﻧﺖ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ) ﺑﺰﺭﮒ ‪ ،‬ﮐﻮﭼﮏ ( ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﺎ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻭ ﻣﻮﺟﻮﺩﻳﺖ ﻭﺍﺣﺪﻱ ﺑﺎ ﻧﺎﻡ‬

‫"ﺍﻳﻨﺘﺮﻧﺖ" ﺭﺍ ﺑﻮﺟﻮﺩ ﺁﻭﺭﺩﻩ ﺍﻧﺪ‪ .‬ﻧﺎﻡ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻓﻮﻕ ﺍﺯ ﺗﺮﮐﻴﺐ ﻭﺍﮊﻩ ﻫﺎﻱ‬ ‫" ‪ "Interconnected‬ﻭ"‪ "Network‬ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺍﺳﺖ‪ ) .‬ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﻬﻢ ﻣﺮﺗﺒﻂ(‪.‬‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﻓﻌﺎﻟﻴﺖ ﺍﻭﻟﻴﻪ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﺳﺎﻝ ‪ ١٩٦٩‬ﻭ ﺑﺎ ﭼﻬﺎﺭ ﺩﺳﺘﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ )‪(host‬‬

‫ﺁﻏﺎﺯ ﻭ ﭘﺲ ﺍﺯ ﺭﺷﺪ ﺑﺎﻭﺭﻧﮑﺮﺩﻧﻲ ﺧﻮﺩ‪ ،‬ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺷﺒﮑﻪ ﺑﻪ ﺑﻴﺶ ﺍﺯ ﺩﻩ‬ ‫ﻫﺎ ﻣﻴﻠﻴﻮﻥ ﺩﺳﺘﮕﺎﻩ ﺭﺳﻴﺪﻩ ﺍﺳﺖ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﻫﻴﭻ ﺳﺎﺯﻣﺎﻥ ﻭ ﻳﺎ ﻣﻮﺳﺴﻪ ﺧﺎﺻﻲ ﺩﺭ ﺟﻬﺎﻥ‬

‫ﺗﻌﻠﻖ ﻧﺪﺍﺭﺩ‪ .‬ﻋﺪﻡ ﺗﻌﻠﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﻭﻳﺎ ﻣﻮﺳﺴﻪ ﺑﻪ ﻣﻨﺰﻟﻪ ﻋﺪﻡ ﻭﺟﻮﺩ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ‬ ‫ﺍﻧﺠﻤﻦ ﻫﺎﻱ ﺧﺎﺻﻲ ﺑﺮﺍﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﺳﺎﺯﻱ ﻧﻴﺴﺖ ‪.‬ﻳﮑﻲ ﺍﺯ ﺍﻳﻦ ﺍﻧﺠﻤﻦ ﻫﺎ‪" ،‬ﺍﻧﺠﻤﻦ ﺍﻳﻨﺘﺮﻧﺖ"‬ ‫ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺳﺎﻝ ‪ ١٩٩٢‬ﺑﺎ ﻫﺪﻑ ﺗﺒﻴﻦ ﺳﻴﺎﺳﺖ ﻫﺎ ﻭ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺟﻬﺖ ﺍﺗﺼﺎﻝ‬

‫ﺑﻪ ﺷﺒﮑﻪ ﺗﺎﺳﻴﺲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

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‫ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺐ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‬

‫ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺑﺨﺸﻲ ﺍﺯ ﺷﺒﮑﻪ ﺗﻠـــــﻘﻲ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻠﻔﻦ ) ﻣﻨﺰﻝ ( ﺑﻪ ﻳﮏ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ‬

‫ﺍﻳﻨﺘﺮﻧﺖ )‪ (ISP‬ﻣﺘﺼﻞ ﻭ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﺑﻌﻨﻮﺍﻥ ﺑﺨﺸﻲ ﺍﺯ ﺷﺒﮑﻪ ﺑﺰﺭﮒ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺤﺴﻮﺏ ﺧﻮﺍﻫﺪ ﺷﺪ‪. .‬ﺑﺮﺧﻲ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺩﺭ ﺍﺩﺍﺭﺍﺕ‬ ‫ﺧﻮﺩ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺴﺘﺮ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‪ ،‬ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ‬

‫ﺩﺭ ﺍﺑﺘﺪﺍ ﺍﺯ ﺷﺒﮑﻪ ﻣﺤﻠﻲ ﻧﺼﺐ ﺷﺪﻩ ﺩﺭ ﺳﺎﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺷﺒﮑﻪ ﻓﻮﻕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺧﻄﻮﻁ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺧﺎﺹ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﺍﻣﮑﺎﻧﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﻳﮏ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻴﺰ ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﺑﺰﺭﮔﺘﺮ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﺎﺷﺪ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺷﺒﮑﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﻴﺸﻤﺎﺭﻱ ﺗﺸﮑﻴﻞ ﺷﺪﻩ‬ ‫ﺍﺳﺖ ) ﺷﺒﮑﻪ ﺍﻱ ﺍﺯ ﺳﺎﻳﺮ ﺷﺒﮑﻪ ﻫﺎ (‬

‫ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺑﺰﺭﮒ ﺩﺍﺭﺍﻱ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﺧﺘﺼﺎﺻﻲ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﻧﺎﺣﻴﻪ ﻫﺎﻱ‬

‫ﻣﺘﻔﺎﻭﺕ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﻫﺮ ﻧﺎﺣﻴﻪ ‪ ،‬ﺷﺮﮐﺖ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺩﺍﺭﺍﻱ ﻳﮏ " ﻧﻘﻄﻪ ﺣﻀﻮﺭ" )‪: POP‬‬

‫‪ (Point of Presence‬ﺍﺳﺖ‪ ، POP .‬ﻣﮑﺎﻧﻲ ﺍﺳﺖ ﮐﻪ ﮐﺎﺭﺑﺮﺍﻥ ﻣﺤﻠﻲ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ‬ ‫ﺑﻪ ﺷﺒﮑﻪ ﺷﺮﮐﺖ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ) .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺷﺒﮑﻪ ﺍﺯ ﺧﻄﻮﻁ ﺗﻠﻔﻦ‬

‫ﻣﻌﻤﻮﻟﻲ ﻭ ﻳﺎ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ(‪.‬‬

‫ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﺳﻄﺢ ﺑﺎﻻ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﮐﻪ ﺗﻮﺳﻂ " ﻧﻘﺎﻁ ﺩﺳﺘﻴﺎﺑﻲ ﺷﺒﮑﻪ"‬ ‫)‪ (Network Access Points: NAP‬ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻓﺮﺽ ﮐﻨﻴﺪ‪ ،‬ﺷﺮﮐﺖ ‪ A‬ﻳﮏ ﻣﺮﮐﺰﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺰﺭﮒ ﺑﺎﺷﺪ‪ .‬ﺩﺭﻫﺮ ﺷﻬﺮﺳﺘﺎﻥ‬

‫ﺍﺻﻠﻲ‪ ،‬ﺷﺮﮐﺖ ‪ A‬ﺩﺍﺭﺍﻱ ﻳﮏ ‪ POP‬ﺍﺳﺖ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ‪ POP‬ﻫﺎ ﺩﺍﺭﺍﻱ ﺍﻣﮑﺎﻧﺎﺕ ﮔﺴﺘﺮﺩﻩ ﺍﻱ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻤﺎﺱ ﮐﺎﺭﺑﺮﺍﻥ ﻣﺤﻠﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺷﺮﮐﺖ ‪ A‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ‪ POP‬ﻫﺎ ﺑﻴﮑﺪﻳﮕﺮ‬ ‫ﻭ ﺷﺮﮐﺖ‪ ،‬ﺍﺯ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﺷﺮﮐﺖ ‪ ،B‬ﻳﮏ‬

‫ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﻫﻤﮑﺎﺭﺑﺎﺷﺪ‪.‬ﺷﺮﮐﺖ ‪ ، B‬ﺳﺎﺧﺘﻤﺎﻧﻬﺎﻱ ﺑﺰﺭﮔﻲ ﺭﺍ ﺩﺭ‬ ‫ﺷﻬﺮﻫﺎﻱ ﺍﺻﻠﻲ ﺍﻳﺠﺎﺩ ﻭ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺩﺭ ﺁﻧﻬﺎ ﻣﺴﺘﻘﺮ ﻧﻤﻮﺩﻩ‬ ‫ﺍﺳﺖ‪ .‬ﺷﺮﮐﺖ ‪ B‬ﺍﺯ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﻓﻴﺒــﺮﻧﻮﺭﻱ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺳﺎﺧﺘـﻤﺎﻧﻬﺎﻱ ﺍﺳﺘﻔـــﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﺗﻤﺎﻡ ﻣﺸﺘﺮﮐﻴﻦ ﺷﺮﮐﺖ ‪ A‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ‬

‫ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻭﺿﻌﻴﺖ ﻣﺸﺘﺮﮐﻴﻦ ﺷﺮﮐﺖ ‪ B‬ﻧﻴﺰ ﻣﺸﺎﺑﻪ ﻣﺸﺘﺮﮐﻴﻦ ﺷﺮﮐﺖ ‪ A‬ﺍﺳﺖ‪ .‬ﺁﻧﻬﺎ ﻧﻴﺰ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ‬ ‫ﻣﺸﺘﺮﮐﻴﻦ ﺷﺮﮐﺖ ‪ A‬ﻭ ﻣﺸﺘﺮﮐﻴﻦ ﺷﺮﮐﺖ ‪ B‬ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺷﺮﮐﺖ ﻫﺎﻱ ‪ A‬ﻭ ‪B‬‬ ‫ﺗﺼﻤﻴﻢ ﻣﻲ ﮔﻴﺮﻧﺪ ﺍﺯ ﻃﺮﻳﻖ ‪ NAP‬ﺩﺭ ﺷﻬﺮﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﮔﺮﺩﻧﺪ‪ .‬ﺗﺮﺍﻓﻴﮏ‬ ‫ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺩﻭ ﺷﺮﮐﺖ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﻫﺎﻱ ﺩﺍﺧﻠﻲ ﻭ ‪ NAP‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻫﺰﺍﺭﺍﻥ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺰﺭﮒ ﺍﺯ ﻃﺮﻳﻖ ‪ NAP‬ﺩﺭ ﺷﻬﺮﻫﺎﻱ‬

‫ﻣﺘﻔﺎﻭﺕ ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﻧﻘﺎﻁ ﻓﻮﻕ )‪ (NAP‬ﺭﻭﺯﺍﻧﻪ ﻣﻴﻠﻴﺎﺭﺩﻫﺎ ﺑﺎﻳﺖ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺟﺎﺑﺠﺎ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺴﻴﺎﺭ ﺑﺰﺭﮒ ﺑﻮﺩﻩ ﮐﻪ ﺗﻤﺎﻡ‬ ‫ﺁﻧﻬﺎ ﺍﺯ ﻃﺮﻳﻖ ‪ NAP‬ﺑﻴـــﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺯ ﻃﺮﻳﻖ ‪ ،NAP‬ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻭ ﺭﻭﺗﺮ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺑﺎﻳﮑﺪﻳﮕﺮ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﭘﻴﺎﻡ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﺭﺑﺮ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ‬ ‫ﻣﺘﻔﺎﻭﺕ ﻋﺒﻮﺭ ﺗﺎ ﺑﻪ ﮐﺎﻣــــﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺳــﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺩﺭ ﮐﻤـﺘﺮ ﺍﺯ ﻳﮏ ﺛﺎﻧﻴﻪ‬

‫ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺭﻭﺗﺮ‪ ،‬ﻣﺴﻴﺮﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺭﺍ ﺗﻌﻴﻴﻦ‬

‫ﻣﻲ ﮐﻨﺪ‪ .‬ﺭﻭﺗﺮﻫﺎ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺧﺎﺻﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﻭﺟﻮﺩ ﻫﺰﺍﺭﺍﻥ ﻣﺴﻴﺮ ﻣﻮﺟﻮﺩ ﺭﺍ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻭ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﮔﺎﻥ ﻣﺮﺑﻮﻃﻪ‬ ‫ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺭﻭﺗﺮ ﺩﻭ ﮐﺎﺭ ﺍﺳﺎﺳﻲ ﺭﺍ ﺩﺭ ﺷﺒﮑﻪ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪:‬‬ ‫•‬

‫ﺍﻳﺠﺎﺩ ﺍﻃﻤﻴﻨﺎﻥ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻋﺪﻡ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﮑﺎﻧﻬﺎﺋﻲ ﮐﻪ ﺑﻪ ﺁﻧﻬﺎ ﻧﻴﺎﺯ‬ ‫ﻧﻤﻲ ﺑﺎﺷﺪ‪.‬‬

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‫ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺍﺭﺳﺎﻝ ﺻﺠﻴﺢ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ‬

‫ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﻭ ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﺭﺍ ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ‬ ‫ﻧﻤﺎﻳﻨﺪ‪ .‬ﺭﻭﺗﺮ ﺑﺎﻋﺚ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ‪ ،‬ﺣﻔﺎﻇﺖ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ‬ ‫ﻳﮑﺪﻳﮕﺮ ﻭ ﭘﻴﺸﮕﻴﺮﻱ ﺍﺯ ﺗﺮﺍﻓﻴﮏ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻫﺰﺍﺭﺍﻥ ﺷﺒﮑﻪ‬ ‫ﮐﻮﭼﮑﺘﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﻳﮏ ﺿﺮﻭﺭﺕ ﺍﺳﺖ‪.‬‬

‫ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٧‬ﻣﻮﺳﺴﻪ ‪ ، NSF‬ﺍﻭﻟﻴﻦ ﺷﺒﮑﻪ ﺑﺎ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﭘﺮ ﺳﺮﻋﺖ ﺭﺍ ﺍﻳﺠﺎﺩ ﮐﺮﺩ‪ .‬ﺷﺒﮑﻪ‬ ‫ﻓﻮﻕ ‪ NSFNET‬ﻧﺎﻣﻴﺪﻩ ﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺷﺒﮑﻪ ﺍﺯ ﻳﮏ ﺧﻂ ﺍﺧﺘﺼﺎﺻﻲ ‪ T1‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ‪١٧٠‬‬ ‫ﺷﺒﮑﻪ ﮐﻮﭼﮑﺘﺮ ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻳﺪﻧﺪ‪ .‬ﺳﺮﻋﺖ ﺷﺒﮑﻪ ﻓﻮﻕ ‪ ١,٥٤٤‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺷﺮﮐﺖ ﻫﺎﻱ ‪ MCI ، IBM‬ﻭ ‪ ، Merit‬ﺷﺒﮑﻪ ﻓﻮﻕ ﺭﺍ ﺗﻮﺳﻌﻪ ﻭ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ‬ ‫ﺁﻥ ﺭﺍ ﺑﻪ ‪ T3‬ﺗﺒﺪﻳﻞ ﮐﺮﺩﻧﺪ) ‪ ٤٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ (‪ .‬ﺑﺮﺍﻱ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺷﺒﮑﻪ ﺍﺯ ﺧﻄﻮﻁ‬ ‫ﻓﻴﺒﺮﻧﻮﺭﻱ )‪ (fiber optic trunk‬ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﻳﺪ‪.‬ﻫﺮ ‪ trunk‬ﺍﺯ ﭼﻨﺪﻳﻦ ﮐﺎﺑﻞ ﻓﻴﺒﺮ‬

‫ﻧﻮﺭﻱ ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﺩ) ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﻇﺮﻓﻴﺖ(‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻫﺮ ﻣﺎﺷﻴﻦ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﻤﺎﺭﻩ ﺷﻨﺎﺳﺎﺋﻲ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﺷﻤﺎﺭﻩ‬ ‫ﺷﻨﺎﺳﺎﺋﻲ ‪ ،‬ﺁﺩﺭﺱ ‪ (Internet Protocol(IP‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻣﺸﺎﺑﻪ‬

‫ﻳﮏ ﺯﺑﺎﻥ ﺍﺭﺗﺒﺎﻃﻲ ﻣﺸﺘﺮﮎ ﺑﺮﺍﻱ ﮔﻔﺘﮕﻮﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ ‪ .‬ﭘﺮﻭﺗﮑﻞ‬

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‫‪ ،‬ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻨﻲ ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﺑﺎ ﺍﺳﺘﻨﺎﺩ ﺑﻪ ﺁﻥ ﮔﻔﺘﮕﻮ ﻭ ﺗﺒﺎﺩﻝ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﺩﻭ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺴﺮ ﺧﻮﺍﻫﺪ ﺷﺪ‪ IP .‬ﺩﺍﺭﺍﻱ ﻓﺮﻣﺘﻲ ﺑﺼﻮﺭﺕ ‪ ٢١١,٢٧,٦٥,١٣٨:‬ﺍﺳﺖ‪.‬‬

‫ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻄﺮ‪ ،‬ﻣﺸﮑﻞ ﺍﺳﺖ‪.‬‬ ‫ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺍﺭﺍﻱ ﻧﺎﻡ ﺍﻧﺤﺼﺎﺭﻱ ﺧﻮﺩ ﺷﺪﻩ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺳﻴﺴﺘﻤﻲ ﺩﻳﮕﺮ‪،‬‬

‫ﺁﺩﺭﺱ ‪ IP‬ﺑﻪ ﻧﺎﻡ ﺩﺭﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺩﺭ ﺁﻏﺎﺯ ﺷﮑﻞ ﮔﻴﺮﻱ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺑﺴﻴﺎﺭ ﮐﻢ ﺑﻮﺩ ﻭ ﻫﺮ‬ ‫ﮐﺎﺭﺑﺮ ﮐﻪ ﻗﺼﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺷﺒﮑﻪ ﺭﺍ ﺩﺍﺷﺖ‪ ،‬ﭘﺲ ﺍﺯ ﺍﺗﺼﺎﻝ ﺑﻪ ﺷﺒﮑﻪ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﺮﺩ‪ .‬ﺭﻭﺵ ﻓﻮﻕ ﻣﺎﺩﺍﻣﻴﮑﻪ ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﻴﺰﺑﺎﻥ ﮐﻢ ﺑﻮﺩﻧﺪ‪ ،‬ﻣﻔﻴﺪ ﻭﺍﻗﻊ ﮔﺮﺩﻳﺪ ﻭﻟﻲ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﮐﺎﺭﺁﺋﻲ ﺭﻭﺵ ﻓﻮﻕ ﺑﺸﺪﺕ ﺍﻓﺖ ﻭ ﻏﻴﺮﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﻳﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻞ‬

‫ﻣﺸﮑﻞ ﻓﻮﻕ ﺍﺯ ﻳﮏ ﻓﺎﻳﻞ ﺳﺎﺩﻩ ﻣﺘﻨﻲ ﮐﻪ ﺗﻮﺳﻂ " ﻣﺮﮐﺰ ﺍﻃﻼﻋﺎﺕ ﺷﺒﮑﻪ " )‪ (NIC‬ﭘﺸﺘﻴﺒﺎﻧﻲ‬

‫ﻣﻲ ﮔﺮﺩﻳﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﻳﺪ‪ .‬ﺑﻤﻮﺍﺯﺍﺕ ﺭﺷﺪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺭﻭﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺑﻴﺸﺘﺮ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ‪ ،‬ﺣﺠﻢ ﻓﺎﻳﻞ ﻓﻮﻕ ﺍﻓﺰﺍﻳﺶ ﻭ ﺑﺪﻟﻴﻞ ﺳﺎﻳﺮ ﻣﺴﺎﺋﻞ ﺟﺎﻧﺒﻲ ‪ ،‬ﻋﻤﻼ" ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ‬

‫ﺑﺮﺍﻱ ﺑﺮﻃﺮﻑ ﻣﺸﮑﻞ " ﺗﺒﺪﻳﻞ ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ " ﻓﺎﻗﺪ ﮐﺎﺭﺁﺋﻲ ﻻﺯﻡ ﺑﻮﺩ‪ .‬ﺩﺭﺳﺎﻝ ‪ ، ١٩٨٣‬ﺳﻴﺴﺘﻢ‬

‫‪ (DNS(Domain Name System‬ﺍﺭﺍﺋﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﻣﺴﺌﻮﻝ ﺗﻄﺒﻴﻖ ﻧﺎﻡ ﺑﻪ‬ ‫ﺁﺩﺭﺱ‪ ،‬ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﺍﺳﺖ ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺑﻪ ﻳﮏ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ‪ ،‬ﺻﺮﻓﺎ" ﻣﻲ ﺗﻮﺍﺗﻨﺪ ﻧﺎﻡ ﺁﻥ ﺭﺍ ﻣﺸﺨﺺ ﮐﺮﺩﻩ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪،DNS‬‬

‫ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻃﻪ ﺁﻥ ﻣﺸﺨﺺ ﺗﺎ ﺯﻣﻴﻨﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬ ‫ﻣﻨﻈﻮﺭ ﺍﺯ " ﻧﺎﻡ" ﭼﻴﺴﺖ ؟‬ ‫ﺩﺭ ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻭﺏ ﻭ ﻳﺎ ﺍﺭﺳﺎﻝ ﻳﮏ ‪ E-Mail‬ﺍﺯ ﻳﮏ "ﻧﺎﻡ ﺣﻮﺯﻩ" ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔـــﺮﺩﺩ‪.‬‬

‫ﻣــــــﺜﻼ" ‪ ( Uniform Resource Locator )URL‬ﻣﺮﺑــــــــــــــــــﻮﻁ ﺑﻪ‬ ‫‪ http://www.oursite.com‬ﺷﺎﻣﻞ " ﻧﺎﻡ ﺣﻮﺯﻩ " ‪ oursite.com‬ﺍﺳﺖ‪.‬‬ ‫ﺩﺭﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ "ﻧﺎﻡ ﺣﻮﺯﻩ "‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺮﺟـﻤﻪ‬

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‫ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﻮﺩ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎﺋﻲ ﺭﺍ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ‬ ‫ﻳﺎ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺒﺪﻳﻞ ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺩﺭ ﺯﻣﺎﻥ ﺩﺭﻳﺎﻓﺖ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ‪ ،‬ﺑﺮ ﺍﺳﺎﺱ ﻳﮑﻲ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﺯﻳﺮ‬ ‫ﺑﺎ ﺁﻥ ﺑﺮﺧﻮﺭﺩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪:‬‬ ‫•‬

‫ﻗﺎﺩﺭ ﺑﻪ ﭘﺎﺳﺦ ﺩﺍﺩﻥ ﺑﻪ ﺩﺭﺧﻮﺍﺳﺖ ﺍﺳﺖ‪ IP .‬ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﻧﺎﻡ ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ ﺭﺍ‬ ‫ﻣﻲ ﺩﺍﻧﺪ ‪.‬‬

‫•‬

‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺩﻳﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ IP‬ﻧﺎﻡ‬

‫•‬

‫ﺍﻋﻼﻡ " ﻋﺪﻡ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ " ﻭ ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﺁﺩﺭﺱ ‪IP‬‬

‫ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ ﺍﺳﺖ‪ ).‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﻣﻤﮑﻦ ﺍﺳﺖ ﺗﮑﺮﺍﺭﮔﺮﺩﺩ(‬

‫ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺩﻳﮕﺮ ﮐﻪ ﺁﮔﺎﻫﻲ ﺑﻴﺸﺘﺮﻱ ﺩﺍﺭﺩ‪.‬‬ ‫•‬

‫ﺍﺭﺍﺋﻪ ﻳﮏ ﭘﻴﺎﻡ ﺧﻄﺎﺀ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻋﺪﻡ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ﺑﺮﺍﻱ ﻧﺎﻡ ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ‬

‫ﻓﺮﺽ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺁﺩﺭﺱ ‪ http://www.oursite.com‬ﺩﺭ ﺑﺮﻧﺎﻣﻪ ﻣﺮﻭﺭﮔﺮ ) ‪ (IE‬ﺗﺎﻳﭗ‬ ‫ﺷﺪﻩ ﺑﺎﺷﺪ‪ .‬ﻣﺮﻭﺭﮔﺮ ﺑﺎ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﺁﺩﺭﺱ ‪ IP‬ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻋﻤﻠﻴﺎﺕ ﺟﺴﺘﺠﻮ ﺑﺮﺍﻱ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ IP‬ﺭﺍ ﺍﺯ‬

‫ﻳﮑﻲ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺳﻄﺢ ﺭﻳﺸﻪ ‪ ،‬ﺁﻏﺎﺯ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺭﻳﺸﻪ‪،‬‬ ‫ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺗﻤﺎﻡ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﮐﻪ ﺷﺎﻣﻞ ﺑﺎﻻﺗﺮﻳﻦ ﺳﻄﺢ ﻧﺎﻣﮕﺬﺍﺭﻱ‬ ‫ﺣﻮﺯﻩ ﻫﺎ ) ‪ ORG ،NET ،COM‬ﻭ ‪ (...‬ﺁﮔﺎﻫﻲ ﺩﺍﺭﻧﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪،DNS‬‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﺁﺩﺭﺱ ‪ http://www.oursite.com‬ﺭﺍ ﻧﻤﻮﺩﻩ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺭﻳﺸﻪ‬

‫ﺍﻋﻼﻡ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ " ﻣﻦ ﺁﺩﺭﺱ ﻓﻮﻕ ﺭﺍ ﻧﻤﻲ ﺩﺍﻧﻢ ﻭﻟﻲ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ‪ COM‬ﺍﻳﻦ ﺍﺳﺖ "‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺷﻤﺎ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪DNS‬‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﺣﻮﺯﻩ ‪ COM‬ﺍﺭﺗﺒﺎﻁ ﻭ ﺩﺭﺧﻮﺍﺳﺖ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‬

‫‪.‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﻱ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬ ‫ﮔﺬﺍﺷﺘﻦ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺳﺖ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺷﻤﺎ ﻗﺮﺍﺭ‬ ‫ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻃﻪ ﺗﻤﺎﺱ ﻭ‬ ‫‪52‬‬

‫ﺩﺭﺧﻮﺍﺳﺖ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﻣﻮﺭﺩ ﻧﻄﺮ ﺭﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺁﺩﺭﺱ ‪IP‬‬

‫ﺳﺎﻳﺖ ﺩﺭﺧﻮﺍﺳﺖ ﺷﺪﻩ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺷﻤﺎ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫ﺑﺎ ﻣﺸﺨﺺ ﺷﺪﻩ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ ﺳﺎﻳﺖ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺍﺯ ﻧﮑﺎﺕ ﻗﺎﺑﻞ ﺗﻮﺟﻪ ﺳﻴﺴﺘﻢ ﻓﻮﻕ‪ ،‬ﻭﺟﻮﺩ ﭼﻨﺪﻳﻦ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻫﻢ ﺳﻄﺢ ‪ DNS‬ﺍﺳﺖ‬

‫‪.‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻳﮑﻲ ﺍﺯ ﺁﻧﻬﺎ ﺑﺎ ﺍﺷﮑﺎﻝ ﻣﻮﺍﺟﻪ ﮔﺮﺩﺩ‪ ،‬ﺍﺯ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺗﺮﺟﻤﻪ ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺳﻴﺴﺘﻢ ﻓﻮﻕ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ‪ Cacheing‬ﺍﺳﺖ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺑﻪ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ﭘﺎﺳﺦ‬ ‫ﻻﺯﻡ ﺭﺍ ﺩﺍﺩ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻃﻪ ﺍﻱ ﺭﺍ ‪ Cache‬ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺯﻣﺎﻧﻴﮑﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ‬

‫ﺑﺮﺍﻱ ﻳﮑﻲ ﺍﺯ ﺣﻮﺯﻩ ﻫﺎﻱ ‪ COM‬ﻭﺍﺻﻞ ﮔﺮﺩﺩ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺍﺯ ﺁﺩﺭﺱ ‪Cache‬‬ ‫ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺭﻭﺯﺍﻧﻪ ﺑﻪ ﻣﻴﻠﻴﺎﺭﺩﻫﺎ ﺩﺭﺧﻮﺍﺳﺖ ﭘﺎﺳﺦ ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﺍﺯ‬ ‫ﻳﮏ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺯﻳﻊ ﺷﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺑﻪ ﻣﺘﻘﺎﺿﻴﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ‬

‫ﺍﻣﮑﺎﻧﺎﺕ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻃﺮﻳﻖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﺗﻤﺎﻡ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭ ﻳﺎ ﺳﺮﻭﻳﺲ‬

‫ﮔﻴﺮﻧﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺎﺷﻴﻦ ﻫﺎﺋﻲ ﮐﻪ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﻣﺎﺷﻴﻦ ﻫﺎ‪ ،‬ﺧﺪﻣﺎﺗﻲ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪،‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﻣﺎﺷﻴﻦ ﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﺧﺪﻣﺎﺕ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪،‬‬

‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ﺷﺎﻣﻞ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫ﻭﺏ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﻭ ‪ ...‬ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﺎﺳﺨﮕﻮﺋﻲ ﺑﻪ ﻧﻴﺎﺯﻫﺎﻱ ﻣﺘﻌﺪﺩ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﺑﻪ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﻣﺘﺼﻞ ﻭ ﺩﺭﺧﻮﺍﺳﺖ ﻳﮏ ﺻﻔﺤﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺷﻮﺩ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﮐﻨﻨﺪﻩ ﺑﻤﻨﺰﻟﻪ ﻳﮏ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺗﻠﻘﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺩﺭﺧﻮﺍﺳﺖ‬

‫ﺷﻤﺎ ) ﺑﻌﻨﻮﺍﻥ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ( ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﺮﻭﻳﺲ‬ ‫‪53‬‬

‫ﺩﻫﻨﺪﻩ ﺻﻔﺤﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺭﺍ ﭘﻴﺪﺍ ﻭ ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﻣﺘﻘﺎﺿﻲ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‬

‫ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺍﺯ ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ﺑﺮﺍﻱ ﺍﻋﻼﻡ ﺩﺭﺧﻮﺍﺳﺖ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻭ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﻣﺴﺌﻮﻝ ﺩﺭﻳﺎﻓﺖ ﺩﺭﺧﻮﺍﺳﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺍﻳﺴﺘﺎ ) ﺛﺎﺑﺖ ( ﺑﻮﺩﻩ ﮐﻪ ﺗﻐﻴﻴﺮ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻳﺪ ‪ ،‬ﺩﺍﺭﺍﻱ ﻳﮏ ‪ IP‬ﻣﺘﻐﻴﺮ ﺑﻮﺩﻩ ﮐﻪ‬ ‫ﺗﻮﺳﻂ ‪ ISP‬ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﺷﻤﺎ ﺍﺧﺘﺼﺎﺹ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺁﺩﺭﺱ‪ IP‬ﺗﺨﺼﻴﺺ ﻳﺎﻓﺘﻪ ﺩﺭ ﻃﻮﻝ‬

‫ﻣﺪﺕ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ) ﻳﮏ ﺟﻠﺴﻪ ﮐﺎﺭﻱ ( ﺛﺎﺑﺖ ﺑﻮﺩﻩ ﻭ ﺗﻐﻴﻴﺮ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺁﺩﺭﺱ ‪IP‬‬ ‫ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺑﻪ ﺷﻤﺎ ﺩﺭ ﺁﻳﻨﺪﻩ ﻭ ﺗﻤﺎﺱ ﻣﺠﺪﺩ ﺑﺎ ‪ ISP‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺗﻐﻴﻴﺮ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺮﺍﮐﺰ ‪ISP‬‬ ‫ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﺧﻮﺩ ﻳﮏ ‪ IP‬ﺍﻳﺴﺘﺎ ﺭﺍ ﻧﺴﺒﺖ ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﺑﺪﻳﻬﻲ ﺍﺳﺖ ﺩﺭ ﺁﻳﻨﺪﻩ‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﭘﻮﺭﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﮐﻪ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺷﻤﺎ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﻧﺴﺒﺖ ﺑﻪ ﻗﺒﻞ ﻣﺘﻔﺎﻭﺕ ﺑﺎﺷﺪ‪.‬‬ ‫ﻫﺮ ﻳﮏ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‪ ،‬ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﺸﺨﺼﻲ ﺍﻧﺠﺎﻡ‬ ‫ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﻣﺎﺷﻴﻦ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﻭ ‪ FTP‬ﻣﺴﺘﻘﺮ‬

‫ﺷﺪﻩ ﺑﺎﺷﻨﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻣﻌﻤﻮﻻ" ﺍﺯ ﭘﻮﺭﺕ ‪ ٨٠‬ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ FTP‬ﺍﺯ ﭘﻮﺭﺕ‬ ‫‪ ٢١‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺍﺯ ﺧﺪﻣﺎﺕ ﻳﮏ ﺳﺮﻭﻳﺲ‬ ‫ﺧﺎﺹ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻭ ﻳﮏ ﺷﻤﺎﺭﻩ ﭘﻮﺭﺕ ﻣﻨﺨﺼﺮ ﺑﻔﺮﺩ ﺍﺳﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﭘﻮﺭﺕ ﺧﺎﺹ ﺑﻪ ﻳﮏ ﺳﺮﻭﻳﺲ ﻣﺘﺼﻞ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﺍﺯ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺧﺎﺹ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪ ..‬ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ﻣﺘﻨﻲ ﺑﻮﺩﻩ ﻭ ﻧﺤﻮﻩ ﻣﮑﺎﻟﻤﻪ ﺑﻴﻦ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﺭﺍ ﺗﺒﻴﻦ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭﺏ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ‬

‫‪ (Hypertext Transfer Protocol(HTTP‬ﺑﺮﺍﻱ ﺑﺮﻗﺮﺍﺭﻱ ﻣﮑﺎﻟﻤﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ‬ ‫ﺧﻮﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺷﺒﮑﻪ ﻫﺎ‪ ،‬ﺭﻭﺗﺮﻫﺎ‪ ،ISPs ،NAPs ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‬ ‫ﻗﺪﺭﺗﻤﻨﺪ‪ ،‬ﻫﻤﮕﻲ ﺳﻬﻤﻲ ﺩﺭ ﺷﮑﻞ ﮔﻴﺮﻱ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻲ ﺑﺰﺭﮔﺘﺮﻳﻦ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﻄﺢ‬ ‫ﺟﻬﺎﻥ ) ﺍﻳﻨﺘﺮﻧﺖ ( ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﻧﺪ‪ .‬ﻋﻨﺎﺻﺮ ﻓﻮﻕ ﺩﺭ ﺯﻧﺪﮔﻲ ﻣﺪﺭﻥ ﺍﻣﺮﻭﺯﻱ ﺟﺎﻳﮕﺎﻫﻲ ﻭﻳﮋﻩ‬ ‫ﺩﺍﺭﻧﺪ‪ .‬ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﺁﻧﻬﺎ‪ ،‬ﺍﻳﻨﺘﺮﻧﺘﻲ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ﻭ ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺯﻧﺪﮔﻲ‬

‫ﺍﻣﺮﻭﺯ ﺑﺸﺮﻳﺖ ﺭﺍ ﺗﻌﺮﻳﻔﻲ ﺩﻳﮕﺮ ﻻﺯﻡ ﺍﺳﺖ!‬

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‫‪ISP‬‬ ‫ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ) ‪ ،( ISP‬ﺧﺪﻣﺎﺕ ﻣﺘﻌﺪﺩﯼ ﻧﻈﻴﺮ ﭘﺴﺖ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﻨﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﺨﺎﺏ‬ ‫ﻳﮏ ‪ ISP‬ﻣﯽ ﺑﺎﻳﺴﺖ ﻓﺎﮐﺘﻮﺭﻫﺎﯼ ﻣﺘﻌﺪﺩﯼ ﺭﺍ ﺑﺮﺭﺳﯽ ﻧﻤﻮﺩ‪ .‬ﺍﻣﻨﻴﺖ‪ ،‬ﻧﻮﻉ ﻭ ﮐﻴﻔﻴﺖ ﺳﺮﻭﻳﺲ‬ ‫ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﻭ ﻗﻴﻤﺖ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺍﺯ ﺟﻤﻠﻪ ﻓﺎﮐﺘﻮﺭﻫﺎﯼ ﻣﻬﻢ ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﺨﺎﺏ ﻳﮏ ‪ISP‬‬

‫ﺍﺳﺖ‪.‬‬ ‫‪ ISP‬ﭼﻴﺴﺖ ؟‬ ‫ﻳﮏ ‪ ISP‬ﻭ ﻳﺎ ‪ ، Internet Service Provider‬ﺷﺮﮐﺘﯽ ﺍﺳﺖ ﮐﻪ ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﯽ‬

‫ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﻭﺏ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﻋﻼﻭﻩ ﺑﺮ ﻧﮕﻬﺪﺍﺭﯼ ﻭ ﭘﺸﺘﻴﺒﺎﻧﯽ ﺍﺯ ﻳﮏ ﺧﻂ ﻣﺴﺘﻘﻴﻢ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻓﻌﺎﻟﻴﺖ ﻫﺎﯼ‬ ‫ﻣﺘﻌﺪﺩ ﺩﻳﮕﺮﯼ ﻧﻈﻴﺮ ﻧﮕﻬﺪﺍﺭﯼ ﻭ ﭘﺸﺘﻴﺎﻧﯽ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﺭﺍ ﻧﻴﺰ ﺍﻧﺠﺎﻡ ﻣﯽ ﺩﻫﻨﺪ‪.‬‬ ‫ﻣﺮﺍﮐﺰ ﻓﻮﻕ ﺑﺎ ﺍﺭﺍﺋﻪ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻻﺯﻡ ) ﺩﺭ ﺻﻮﺭﺕ ﺿﺮﻭﺭﺕ (‪ ،‬ﻳﮏ ﺭﻣﺰ ﻋﺒﻮﺭ ﺣﻔﺎﻇﺖ‬ ‫ﺷﺪﻩ ﻭ ﻳﮏ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﺑﺮﺍﯼ ﺗﻤﺎﺱ ﺑﺎ ﺷﺒﮑﻪ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻣﺒﺎﺩﻟﻪ ﻧﺎﻣﻪ ﻫﺎﯼ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﻨﺪ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﻣﺮﺍﮐﺰ ‪ ISP‬ﺧﺪﻣﺎﺕ ﺍﺿﺎﻓﻪ‬ ‫ﺩﻳﮕﺮﯼ ﺭﺍ ﻧﻴﺰ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻣﺮﺍﮐﺰ ‪ ISP‬ﺩﺍﺭﺍﯼ ﺍﺑﻌﺎﺩ ﻭ ﺍﻧﺪﺍﺯﻩ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﺁﻧﺎﻥ ﺗﻮﺳﻂ ﺍﻓﺮﺍﺩﯼ‬

‫ﺍﻧﺪﮎ ﺍﺩﺍﺭﻩ ﻣﯽ ﺷﻮﻧﺪ ﻭ ﺗﻌﺪﺍﺩﯼ ﺩﻳﮕﺮ ﺷﺮﮐﺖ ﻫﺎﺋﯽ ﺑﺰﺭﮒ ﻣﯽ ﺑﺎﺷﻨﺪ ﮐﻪ ﺧﺪﻣﺎﺕ ﻣﺘﻨﻮﻋﯽ‬ ‫ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﻨﺪ ‪ .‬ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺍﺭﺍﯼ ﺣﻮﺯﻩ ﻫﺎﯼ‬

‫ﻋﻤﻠﻴﺎﺗﯽ ﻣﺘﻔﺎﻭﺗﯽ ﻧﻴﺰ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﺑﺮﺧﯽ ﺍﺯ ﺁﻧﺎﻥ ﺧﺪﻣﺎﺕ ﺧﻮﺩ ﺭﺍ ﺻﺮﻓﺎ" ﺩﺭ ﺳﻄﺢ ﻳﮏ‬

‫ﺷﻬﺮﺳﺘﺎﻥ ﺍﺭﺍﺋﻪ ﺩﺍﺩﻩ ﻭ ﺑﺮﺧﯽ ﺩﻳﮕﺮ ﺩﺍﺭﺍﯼ ﻗﺎﺑﻠﻴﺖ ﻫﺎﯼ ﻣﻨﻄﻘﻪ ﺍﯼ ﻭ ﺣﺘﯽ ﺑﻴﻦ ﺍﻟﻤﻠﻠﯽ‬ ‫ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﻣﺮﺍﮐﺰ ‪ ISP‬ﭼﻪ ﺳﺮﻭﻳﺲ ﻫﺎﺋﯽ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﺩﻫﻨﺪ ؟‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﺧﺪﻣﺎﺗﯽ ﮐﻪ ﺗﻮﺳﻂ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺭﺍﺋﻪ‬ ‫ﻣﻴﮕﺮﺩﺩ ﺑﺴﻴﺎﺭ ﻣﺘﻨﻮﻉ ﻭ ﺩﺭ ﻋﻴﻦ ﺣﺎﻝ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﺗﻘﺮﻳﺒﺎ" ﺗﻤﺎﻣﯽ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺳﺮﻭﻳﺲ ﻫﺎﺋﯽ ﻧﻈﻴﺮ ﭘﺴﺖ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﻧﻮﻉ ﻭ ﮐﻴﻔﻴﺖ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻭ ﭘﺸﺘﻴﺒﺎﻧﯽ ﻓﻨﯽ ﺗﻮﺳﻂ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ‬

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‫ﺍﮐﺜﺮ ﻣﺮﺍﮐﺰ ‪ ، ISP‬ﺳﺮﻭﻳﺲ ﻫﺎﺳﺘﻴﻨﮓ ﻭﺏ ﺭﺍ ﻧﻴﺰ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺩﺍﺭﺍﯼ ﺳﻄﻮﺡ ﻣﺘﻔﺎﻭﺗﯽ ﺍﺳﺖ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﻓﻮﻕ ‪ ،‬ﻣﺘﻘﺎﺿﻴﺎﻥ ﻣﯽ ﺗﻮﺍﻧﻨﺪ ﺻﻔﺤﺎﺕ ﻭﺏ ﺷﺨﺼﯽ ﺧﻮﺩ ﺭﺍ ﺍﻳﺠﺎﺩ ﻭ ﺍﺯ ﺁﻧﺎﻥ‬ ‫ﻧﮕﻬﺪﺍﺭﯼ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺍﺧﺘﺼﺎﺹ ﻓﻀﺎﯼ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﯼ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﺟﻤﻠﻪ‬

‫ﻭﻇﺎﻳﻒ ﻳﮏ ‪ ISP‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺑﺮﺧﯽ ﺍﺯ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺳﺮﻭﻳﺲ ﻫﺎﺋﯽ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﻃﺮﺍﺣﯽ ﻭ‬ ‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺻﻔﺤﺎﺕ ﻭﺏ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺗﻌﺪﺍﺩﯼ ﺍﺯ ﻣﺮﺍﮐﺰ ‪ ISP‬ﮔﺰﻳﻨﻪ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﺭﺍ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻧﻮﻉ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﻨﺪ‪ ، DSL ، Dial-up ) .‬ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ(‪ .‬ﺑﺮﺧﯽ‬ ‫ﺍﺯ ﻣﺮﺍﮐﺰ ‪ ISP‬ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺻﺮﻓﺎ" ﺍﺯ ﻃﺮﻳﻖ ﺧﻄﻮﻁ ﻣﻌﻤﻮﻟﯽ ﺗﻠﻔﻦ‬

‫ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫ﺍﮐﺜﺮ ﻣﺮﺍﮐﺰ ‪ ISP‬ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺗﯽ ﻧﻈﻴﺮ ﺗﻬﻴﻪ ‪ Backup‬ﺍﺯ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ‬ ‫ﻓﺎﻳﻞ ﻫﺎﯼ ﻭﺏ ﺭﺍ ﻧﻴﺰ ﺍﻧﺠﺎﻡ ﻣﯽ ﺩﻫﻨﺪ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﯽ ﮐﻪ ﺑﺎﺯﻳﺎﻓﺖ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬ ‫ﻭ ﻓﺎﻳﻞ ﻫﺎﯼ ﻭﺏ ﺑﺮﺍﯼ ﺷﻤﺎ ﻣﻬﻢ ﺍﺳﺖ ) ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ (‪ ،‬ﻳﮏ ‪ ISP‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ ﮐﻪ ‪ Backup‬ﮔﺮﻓﺘﻦ ﺍﺯ ﺩﺍﺩﻩ ﻫﺎ ﺭﺍ ﺩﺭ ﺩﺳﺘﻮﺭ ﮐﺎﺭ ﺧﻮﺩ ﻗﺮﺍﺭ ﺩﺍﺩﻩ‬ ‫ﺍﺳﺖ‪.‬‬

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‫ﭼﮕﻮﻧﻪ ﻳﮏ ‪ ISP‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﻢ؟‬

‫ﺑﺮﺍﯼ ﺍﻧﺘﺨﺎﺏ ﻳﮏ ‪ ISP‬ﭘﺎﺭﺍﻣﺘﺮﻫﺎﯼ ﻣﺘﻌﺪﺩﯼ ﺑﺮﺭﺳﯽ ﻣﯽ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺍﻣﻨﻴﺖ ‪ :‬ﺁﻳﺎ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺍﺯ ﺭﻭﻳﮑﺮﺩﻫﺎﯼ ﻣﻨﺎﺳﺐ ﺍﻣﻨﻴﺘﯽ ﺩﺭ ﺟﻬﺖ ﺣﻔﺎﻇﺖ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ ؟ ﺁﻳﺎ ﺍﺯ ﺭﻣﺰﻧﮕﺎﺭﯼ ﻭ ‪ SSL‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻔﺎﻇﺖ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺍﺭﺳﺎﻟﯽ ﺷﻤﺎ ﻧﻈﻴﺮ ﻧﺎﻡ ﻭ ﺭﻣﺰ ﻋﺒﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ؟‬

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‫ﻣﺤﺮﻣﺎﻧﮕﯽ ‪ :‬ﺁﻳﺎ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺩﺍﺭﺍﯼ ﻳﮏ ﺳﻴﺎﺳﺖ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺩﺭ ﺧﺼﻮﺹ ﺭﻋﺎﻳﺖ‬ ‫ﺣﺮﻳﻢ ﺧﺼﻮﺻﯽ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺖ ؟ ﺁﻳﺎ ﺧﻴﺎﻝ ﺷﻤﺎ ﺍﺯ ﺍﻳﻦ ﺑﺎﺑﺖ ﺭﺍﺣﺖ ﺍﺳﺖ ﮐﻪ ﭼﻪ‬ ‫ﺍﻓﺮﺍﺩﯼ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﺷﻤﺎ ﺩﺳﺘﻴﺎﺑﯽ ﺩﺍﺭﻧﺪ؟ ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺁﻧﺎﻥ ﺍﺯ ﺍﻃﻼﻋﺎﺕ‬

‫ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺍﺳﺖ؟‬ ‫•‬

‫ﺳﺮﻭﻳﺲ ﻫﺎ ‪ :‬ﺁﻳﺎ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻈﺮ ﺷﻤﺎ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﺪ؟ ﺁﻳﺎ‬

‫ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﺎﻣﻴﻦ ﮐﻨﻨﺪﻩ ﻧﻴﺎﺯ ﺷﻤﺎ ﻣﯽ ﺑﺎﺷﻨﺪ؟ ﺁﻳﺎ ﭘﺸﺘﻴﺒﺎﻧﯽ ﻻﺯﻡ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺳﺮﻭﻳﺲ ﻫﺎ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺷﻤﺎ ﮔﺬﺍﺷﺘﻪ ﻣﯽ ﺷﻮﺩ؟‬ ‫•‬

‫ﻗﻴﻤﺖ ‪ :‬ﺁﻳﺎ ﻗﻴﻤﺖ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺗﻮﺳﻂ ‪ ISP‬ﻗﺎﺑﻞ ﻗﺒﻮﻝ ﺍﺳﺖ؟ ﺁﻳﺎ ﻗﻴﻤﺖ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﻌﺪﺍﺩ ﻭ ﻧﻮﻉ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‪ ،‬ﻣﻨﻄﻘﯽ ﺍﺳﺖ؟ ﺁﻳﺎ ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺩﺭﻳﺎﻓﺖ ﺧﺪﻣﺎﺕ ﺍﺭﺯﺍﻥ ﺗﺮ‪ ،‬ﺍﺯ ﮐﻴﻔﻴﺖ ﻭ ﺍﻣﻨﻴﺖ ﭼﺸﻢ ﭘﻮﺷﯽ ﻣﯽ ﻧﻤﺎﺋﻴﺪ؟‬

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‫ﺍﻋﻤﺘﺎﺩ ﭘﺬﻳﺮﯼ ‪ :‬ﺁﻳﺎ ﺑﻪ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﻣﯽ ﺗﻮﺍﻥ ﺍﻋﺘﻤﺎﺩ‬ ‫ﺩﺍﺷﺖ ﻭ ﻳﺎ ﺩﺭ ﺍﻏﻠﺐ ﻣﻮﺍﺭﺩ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﺩﻻﻳﻞ ﻣﺘﻔﺎﻭﺗﯽ ﻧﻈﻴﺮ‬

‫ﭘﺸﺘﻴﺒﺎﻧﯽ ﻭ ﻧﮕﻬﺪﺍﺭﯼ‪ ،‬ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩ ﮐﺎﺭﺑﺮﺍﻥ ﻭ ‪ ،...‬ﻏﻴﺮ ﻓﻌﺎﻝ ﺑﻮﺩﻩ ﻭ ﻋﻤﻼ" ﺍﻣﮑﺎﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﯽ ﮐﻪ ﺑﻪ ﺩﻻﻳﻞ ﻣﺘﻔﺎﻭﺗﯽ ﻻﺯﻡ ﺍﺳﺖ ﺑﺮﺧﯽ ﺍﺯ‬ ‫ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﻏﻴﺮ ﻓﻌﺎﻝ ﮔﺮﺩﻧﺪ ﺁﻳﺎ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﮑﺎﻧﻴﺰﻡ ﻫﺎﯼ‬ ‫ﺧﺎﺻﯽ ﺑﻪ ﺷﻤﺎ ﺍﻃﻼﻉ ﺩﺍﺩﻩ ﻣﯽ ﺷﻮﺩ؟‬ ‫•‬

‫ﭘﺸﺘﻴﺒﺎﻧﯽ ﮐﺎﺭﺑﺮﺍﻥ ‪ :‬ﺁﻳﺎ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺩﺍﺭﺍﯼ ﺑﺨﺶ ﭘﺸﺘﻴﺒﺎﻧﯽ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺖ؟ ﻧﺤﻮﻩ‬ ‫ﺑﺮﺧﻮﺭﺩ ﭘﺮﺳﻨﻞ ﺑﺨﺶ ﭘﺸﺘﻴﺒﺎﻧﯽ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺍﺳﺖ؟ ﺁﻳﺎ ﺁﻧﺎﻥ ﺩﺍﺭﺍﯼ ﺩﺍﻧﺶ ﻻﺯﻡ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﭘﺎﺳﺨﮕﻮﺋﯽ ﻣﻨﻄﻘﯽ ﺑﻪ ﺳﻮﺍﻻﺕ ﺷﻤﺎ ﻣﯽ ﺑﺎﺷﻨﺪ؟‬ ‫‪58‬‬

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‫ﺳﺮﻋﺖ ‪ :‬ﺳﺮﻋﺖ ﺍﺗﺼﺎﻝ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﭼﮕﻮﻧﻪ ﺍﺳﺖ ؟ ﺁﻳﺎ ﺍﻳﻦ ﺳﺮﻋﺖ ﺑﻪ‬

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‫ﮐﻴﻔﻴﺖ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ‪ :‬ﺁﻳﺎ ‪ ISP‬ﺍﻧﺘﺨﺎﺑﯽ ﺩﺍﺭﺍﯼ ﻋﻤﻠﮑﺮﺩﯼ ﻣﺜﺒﺖ ﺩﺭ ﮐﺎﺭﻧﺎﻣﻪ ﻓﻌﺎﻟﻴﺖ‬

‫ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﯽ ﺷﻤﺎ ﺑﻪ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻭﺏ ﮐﺎﻓﯽ ﺍﺳﺖ؟‬

‫ﺧﻮﺩ ﺍﺳﺖ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻧﯽ ﮐﻪ ﻗﺒﻼ" ﺍﺯ ﺧﺪﻣﺎﺕ ﺁﻧﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ ،‬ﺍﺯ‬ ‫ﮐﻴﻔﻴﺖ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺭﺍﺿﯽ ﻣﯽ ﺑﺎﺷﻨﺪ؟‬

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‫‪DSL‬‬ ‫ﺑﺮﺍﯼ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻮﺩﻡ‬ ‫ﻣﻌﻤﻮﻟﯽ‪ ،‬ﻣﻮﺩﻡ ﮐﺎﺑﻠﯽ‪ ،‬ﺷﺒﮑﻪ ﻣﺤﻠﯽ ﻭ ﻳﺎ ﺧﻄﻮﻁ ‪،(Digital Subscriber Line(DSL‬‬ ‫ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺑﺮﺍﯼ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﯽ ﺑﺎﺷﻨﺪ‪ ، DSL .‬ﻳﮏ ﺍﺗﺼﺎﻝ‬

‫ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﯼ ﻣﻌﻤﻮﻟﯽ ﺗﻠﻔﻦ ﺑﺮﺍﯼ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻓﺮﺍﻫﻢ‬ ‫ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﻣﺰﺍﻳﺎﯼ ‪DSL‬‬ ‫•‬

‫ﺩﺭ ﺯﻣﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻂ ﺗﻠﻔﻦ ﺑﺮﺍﯼ ﺗﻤﺎﺱ ﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﻫﻤﭽﻨﺎﻥ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﺩﺍﺭﺍﯼ ﺳﺮﻋﺘﯽ ﺑﻤﺮﺍﺗﺐ ﺑﺎﻻﺗﺮ ﺍﺯ ﻣﻮﺩﻡ ﻫﺎﯼ ﻣﻌﻤﻮﻟﯽ ﺍﺳﺖ ) ‪ ٥/١‬ﻣﮕﺎﺑﺎﻳﺖ (‪.‬‬

‫ﻧﻴﺎﺯ ﺑﻪ ﮐﺎﺑﻞ ﮐﺸﯽ ﺟﺪﻳﺪ ﻧﺒﻮﺩﻩ ﻭ ﻫﻤﭽﻨﺎﻥ ﻣﯽ ﺗﻮﺍﻥ ﺍﺯ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻣﻮﺟﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﮐﺮﺩ‪.‬‬

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‫ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ‪ ، DSL‬ﻣﻮﺩﻡ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺩﺭ ﺯﻣﺎﻥ ﻧﺼﺐ ﺧﻂ ﻓﻮﻕ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬ ‫ﻣﺸﺘﺮﮎ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬

‫ﺍﺷﮑﺎﻻﺕ ‪DSL‬‬ ‫•‬

‫ﻳﮏ ﺍﺗﺼﺎﻝ ‪ DSL‬ﻫﺮ ﺍﻧﺪﺍﺯﻩ ﮐﻪ ﺑﻪ ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﻧﺰﺩﻳﮑﺘﺮ ﺑﺎﺷﺪ‪،‬‬

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‫ﺳﺮﻋﺖ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﻧﺴﺒﺖ ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺳﺖ ) ﻋﺪﻡ ﻭﺟﻮﺩ ﺗﻮﺍ‬

‫ﺩﺍﺭﺍﯼ ﮐﻴﻔﻴﺖ ﺑﻬﺘﺮﯼ ﺍﺳﺖ‪.‬‬

‫ﺯﻥ ﻣﻨﻄﻘﯽ (‬

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‫ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺩﺭ ﻫﺮ ﻣﺤﻞ ﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ﻧﻤﯽ ﺑﺎﺷﺪ‪.‬‬

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‫ﻣﺒﺎﻧﯽ ‪DSL‬‬ ‫ﺩﺭ ﺯﻣﺎﻥ ﻧﺼﺐ ﻳﮏ ﺗﻠﻔﻦ ) ﺍﺳﺘﺎﻧﺪﺍﺭﺩ( ﺩﺭ ﺍﻏﻠﺐ ﮐﺸﻮﺭﻫﺎ ﺍﺯ ﻳﮏ ﺯﻭﺝ ﮐﺎﺑﻞ ﻣﺴﯽ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﮐﺎﺑﻞ ﻣﺴﯽ ﺩﺍﺭﺍﯼ ﭘﻬﻨﺎﯼ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﯼ ﻧﺴﺒﺖ ﺑﻪ ﺁﻥ ﭼﻴﺰﯼ ﺍﺳﺖ ﮐﻪ‬

‫ﺩﺭ ﻣﮑﺎﻟﻤﺎﺕ ﺗﻠﻔﻨﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ ) ﺑﺨﺶ ﻋﻤﺪﻩ ﺍﯼ ﺍﺯﻇﺮﻓﻴﺖ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﯽ‬ ‫ﮔﺮﺩﺩ (‪ DSL .‬ﺍﺯ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﺑﻼﺍﺳﺘﻔﺎﺩﻩ ﺑﺪﻭﻥ ﺗﺎﺛﻴﺮ ﮔﺬﺍﺭﯼ ﻣﻨﻔﯽ ﺑﺮ ﮐﻴﻔﻴﺖ ﻣﮑﺎﻟﻤﺎﺕ‬

‫ﺻﻮﺗﯽ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪ ) .‬ﺗﻄﺒﻴﻖ ﻓﺮﮐﺎﻧﺲ ﻫﺎﯼ ﺧﺎﺹ ﺑﻪ ﻣﻨﻈﻮﺭﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺹ(‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ‪ ، DSL‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﻳﮏ ﺧﻂ ﺗﻠﻔﻦ ﻣﻌﻤﻮﻟﯽ‬

‫ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪ .‬ﺍﮐﺜﺮ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻭ ﺗﺠﻬﻴﺰﺍﺕ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﯼ ﻣﺤﺪﻭﺩﻳﺖ ﻓﺮﮐﺎﻧﺴﯽ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬ ‫ﺳﻮﺋﻴﭻ‪ ،‬ﺗﻠﻔﻦ ﻭ ﺳﺎﻳﺮ ﺗﺠﻬﻴﺰﺍﺗﯽ ﻣﯽ ﺑﺎﺷﻨﺪ ﮐﻪ ﺑﻨﻮﻋﯽ ﺩﺭ ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ ﺳﻴﮕﻨﺎ ﻝ ﻫﺎ ﺩﺧﺎﻟﺖ‬

‫ﺩﺍﺭﻧﺪ‪ .‬ﺻﺪﺍﯼ ﺍﻧﺴﺎﻥ ) ﺩﺭ ﻳﮏ ﻣﮑﺎﻟﻤﻪ ﺻﻮﺗﯽ ﻣﻌﻤﻮﻟﯽ ( ﺗﻮﺳﻂ ﺳﻴﮕﻨﺎﻝ ﻫﺎﺋﯽ ﺑﺎ ﻓﺮﮐﺎﻧﺲ‬ ‫ﺑﻴﻦ ﺻﻔﺮ ﺗﺎ ‪ ٣٤٠٠‬ﻗﺎﺑﻞ ﺍﻧﺘﻘﺎﻝ ﺍﺳﺖ‪ .‬ﻣﺤﺪﻭﺩﻩ ﻓﻮﻕ ﺑﺴﻴﺎﺭ ﻧﺎﭼﻴﺰ ﺍﺳﺖ )ﻣﺜﻼ" ﺍﻏﻠﺐ‬ ‫ﺑﻠﻨﺪﮔﻮﻫﺎﯼ ﺍﺳﺘﺮﻳﻮ ﮐﻪ ﺩﺍﺭﺍﯼ ﻣﺤﺪﻭﺩﻩ ﺑﻴﻦ ‪ ٢٠‬ﺗﺎ ‪ ٢٠,٠٠٠‬ﻫﺮﺗﺰ ﻣﯽ ﺑﺎﺷﻨﺪ(‪ .‬ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺷﺪﻩ ﺩﺭ ﺳﻴﺴﺘﻢ ﺗﻠﻔﻦ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺘﻘﺎﻝ ﺳﻴﮕﻨﺎﻝ ﻫﺎﺋﯽ ﺑﺎ ﻇﺮﻓﻴﺖ ﭼﻨﺪﻳﻦ ﻣﻴﻠﻴﻮﻥ ﻫﺮﺗﺰ ﻣﯽ ﺑﺎﺷﺪ‪.‬‬

‫ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺩﺭ ﻣﮑﺎﻟﻤﺎﺕ ﺻﻮﺗﯽ ﺻﺮﻓﺎ" ﺍﺯ ﺑﺨﺶ ﺑﺴﻴﺎﺭ ﻣﺤﺪﻭﺩﯼ ﺍﺯ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﻣﻮﺟﻮﺩ‪،‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻧﺸﺪﻩ ﻣﯽ ﺗﻮﺍﻥ ﻋﻼﻭﻩ ﺑﺮ ﺑﻬﺮﻩ ﺑﺮﺩﺍﺭﯼ ﺍﺯ‬

‫ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﯼ ﻣﻮﺟﻮﺩ‪ ،‬ﺑﮕﻮﻧﻪ ﺍﯼ ﻋﻤﻞ ﻧﻤﻮﺩ ﮐﻪ ﮐﻴﻔﻴﺖ ﻣﮑﺎﻟﻤﺎﺕ ﺻﻮﺗﯽ ﻧﻴﺰ ﺩﭼﺎﺭ ﺍﻓﺖ‬ ‫ﻧﮕﺮﺩﻧﺪ‪ .‬ﺗﺠﻬﻴﺰﺍﺕ ﭘﻴﺸﺮﻓﺘﻪ ﺍﯼ ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺼﻮﺭﺕ ﺩﻳﺠﻴﺘﺎﻝ ﺍﺭﺳﺎﻝ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻗﺎﺩﺭ‬ ‫ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻇﺮﻓﻴﺖ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﺑﺼﻮﺭﺕ ﮐﺎﻣﻞ ﻣﯽ ﺑﺎﺷﻨﺪ‪ DSL .‬ﭼﻨﻴﻦ ﻫﺪﻓﯽ ﺭﺍ ﺩﻧﺒﺎﻝ‬ ‫ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺩﺭ ﺍﻏﻠﺐ ﻣﻨﺎﺯﻝ ﻭ ﺍﺩﺍﺭﺍﺕ ﺑﺮﺧﯽ ﺍﺯ ﮐﺸﻮﺭﻫﺎﯼ ﺩﻧﻴﺎ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﻳﮏ ‪ DSL‬ﻧﺎﻣﺘﻘﺎﺭﻥ‬ ‫)‪ (ADSL‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ADSL .‬ﻓﺮﮐﺎﻧﺲ ﻫﺎﯼ ﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ﺩﺭﻳﮏ ﺧﻂ ﺭﺍ ﺗﻘﺴﻴﻢ ﺗﺎ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺎﺩﺭ ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﻓﺮﺽ ﺑﺮ ﺍﻳﻦ‬

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‫ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﺳﺮﻋﺖ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

‫ﺑﺎﺷﺪ‪.‬‬

‫ﺻﻮﺕ ﻭ ﺩﺍﺩﻩ‬ ‫ﮐﻴﻔﻴﺖ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻳﻖ ‪ ، DSL‬ﺑﻪ ﻣﺴﺎﻓﺖ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﮐﻨﻨﺪﻩ ﻭ ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺑﺴﺘﮕﯽ ﺩﺍﺭﺩ‪ ADSL .‬ﺍﺯ ﻳﮏ ﺗﮑﻨﻮﻟﻮﮊﯼ ﺑﺎ ﻧﺎﻡ "‬ ‫ﺗﮑﻨﻮﻟﻮﮊﯼ ﺣﺴﺎﺱ ﺑﻪ ﻣﺴﺎﻓﺖ " ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻤﻮﺍﺯﺍﺕ ﺍﻓﺰﺍﻳﺶ ﻃﻮﻝ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ‪،‬‬ ‫ﮐﻴﻔﻴﺖ ﺳﻴﮕﻨﺎﻝ ﺍﻓﺖ ﻭ ﺳﺮﻋﺖ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﮐﺎﻫﺶ ﭘﻴﺪﺍ ﻣﯽ ﻧﻤﺎﻳﺪ‪ ADSL .‬ﺩﺍﺭﺍﯼ‬ ‫ﻣﺤﺪﻭﺩﻳﺖ ‪ ١٨,٠٠٠‬ﻓﻮﺕ ) ‪ ٥,٤٦٠‬ﻣﺘﺮ ( ﺍﺳﺖ‪ .‬ﮐﺎﺭﺑﺮﺍﻧﯽ ﮐﻪ ﺩﺭ ﻣﺠﺎﻭﺭﺕ ﻭ ﻧﺰﺩﻳﮑﯽ‬ ‫ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ DSL‬ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪ ،‬ﺩﺍﺭﺍﯼ ﮐﻴﻔﻴﺖ ﻭ ﺳﺮﻋﺖ ﻣﻨﺎﺳﺒﯽ ﺑﻮﺩﻩ ﻭ‬

‫ﺑﻤﻮﺍﺯﺍﺕ ﺍﻓﺰﺍﻳﺶ ﻣﺴﺎﻓﺖ ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻧﻈﺮ ﮐﻴﻔﻴﺖ ﻭ ﺳﺮﻋﺖ ﺩﭼﺎﺭ ﺍﻓﺖ ﺧﻮﺍﻫﻨﺪ‬ ‫ﺷﺪ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ ADSL‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﺑﺎﻻﺗﺮﻳﻦ ﺳﺮﻋﺖ ﺩﺭ ﺣﺎﻟﺖ " ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﮐﺎﺭﺑﺮ "‬

‫)‪ (Downstream‬ﺗﺎ ‪ ٨‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪ ) .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﯽ ﺣﺪﺍﮐﺜﺮ ﻣﺴﺎﻓﺖ‬ ‫‪ ٦,٠٠٠‬ﻓﻮﺕ ﻭ ﻳﺎ ‪ ١,٨٢٠‬ﻣﺘﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ (‪ .‬ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ " ﺍﺯ ﮐﺎﺭﺑﺮ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ"‬

‫)‪ (Upstream‬ﺩﺍﺭﺍﯼ ﻣﺤﺪﻭﺩﻩ ‪ ٦٤٠‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﻋﻤﻞ‪ ،‬ﺑﻬﺘﺮﻳﻦ‬ ‫ﺳﺮﻋﺖ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﮐﺎﺭﺑﺮ‪ ١,٥ ،‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻭ‬ ‫ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ‪ ٦٤٠ ،‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬ ‫ﺍﺳﺖ‪.‬‬

‫ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﻳﻦ ﺳﻮﺍﻝ ﺩﺭ ﺫﻫﻦ ﺧﻮﺍﻧﻨﺪﮔﺎﻥ ﻣﻄﺮﺡ ﮔﺮﺩﺩ ﮐﻪ ﺍﮔﺮ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ DSL‬ﺩﺍﺭﺍﯼ‬ ‫ﻣﺤﺪﻭﺩﻳﺖ ﻓﺎﺻﻠﻪ ﺍﺳﺖ‪ ،‬ﭼﺮﺍ ﻣﺤﺪﻭﺩﻳﺖ ﻓﻮﻕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﮑﺎﻟﻤﺎﺕ ﺻﻮﺗﯽ ﺻﺪﻕ‬ ‫ﻧﻤﯽ ﮐﻨﺪ؟ ﺩﺭ ﭘﺎﺳﺦ ﺑﺎﻳﺪ ﺑﻪ ﻭﺟﻮﺩ ﻳﮏ ﺗﻔﻮﻳﺖ ﮐﻨﻨﺪﻩ ﮐﻮﭼﮏ ﮐﻪ ‪ Loading coils‬ﻧﺎﻣﻴﺪﻩ‬

‫ﻣﯽ ﺷﻮﺩ‪ ،‬ﺍﺷﺎﺭﻩ ﮐﺮﺩ‪ .‬ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺍﺯ ﺗﻔﻮﻳﺖ ﮐﻨﻨﺪﻩ ﻓﻮﻕ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻘﻮﻳﺖ ﺳﻴﮕﻨﺎﻝ‬ ‫ﺻﻮﺗﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﺘﺎﺳﻔﺎﻧﻪ ﺗﻘﻮﻳﺖ ﮐﻨﻨﺪﻩ ﻓﻮﻕ ﺑﺎ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ‪ ADSL‬ﺳﺎﺯﮔﺎﺭ‬

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‫ﻧﻴﺴﺖ ‪ .‬ﻻﺯﻡ ﺑﻪ ﺫﮐﺮ ﺍﺳﺖ ﮐﻪ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ‪ ، ADSL‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﺨﺸﯽ ﺍﺯ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ‬ ‫ﺍﺯ ﻧﻮﻉ ﻓﻴﺒﺮ ﻧﻮﺭﯼ ﺑﺎﺷﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

‫ﺗﻘﺴﻴﻢ ﺳﻴﮕﻨﺎﻝ‬

‫ﺍﺯ ﺩﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻣﺘﻔﺎﻭﺕ ﺑﺮﺍﯼ ﺗﻘﺴﻴﻢ ﺳﻴﮕﻨﺎﻟﻬﺎ ) ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺳﺎﺯﮔﺎﺭ ﻧﻤﯽ ﺑﺎﺷﻨﺪ(‪،‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ ،ANSI‬ﺑﺮﺍﯼ ‪ ADSL‬ﺳﻴﺴﺘﻤﯽ ﺑﺎ ﻧﺎﻡ ‪Discrete‬‬ ‫‪ Multitone‬ﺍﺳﺖ‪ .(DMT) .‬ﺍﮐﺜﺮ ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﺗﺠﻬﻴﺰﺍﺕ ‪ DSL‬ﺍﺯ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻓﻮﻕ‬ ‫ﺗﺒﻌﻴﺖ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺩﻳﮕﺮﯼ ﮐﻪ ﻧﺴﺒﺖ ﺑﻪ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ DMT‬ﻗﺪﻳﻤﯽ ﺗﺮ ﻭ ﺑﺴﺎﺩﮔﯽ‬ ‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻣﯽ ﮔﺮﺩﺩ‪ ،‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‪ Carrierless Amplitude phase/‬ﺍﺳﺖ)‪.(CAP‬‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ ، CAP‬ﺳﻴﮕﻨﺎﻝ ﻫﺎ ﺭﺍ ﺑﻪ ﺳﻪ ﺑﺎﻧﺪ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪ :‬ﻣﮑﺎﻟﻤﺎﺕ ﺗﻠﻔﻦ ﺩﺍﺭﺍﯼ‬

‫ﺑﺎﻧﺪ ﺻﻔﺮ ﺗﺎ ‪ ٤‬ﮐﻴﻠﻮ ﻫﺮﺗﺰ‪ ،‬ﮐﺎﻧﺎﻝ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮐﺎﺭﺑﺮ ﺑﺮﺍﯼ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺍﺭﺍﯼ‬ ‫ﺑﺎﻧﺪﯼ ﺑﻴﻦ ‪ ٢٥‬ﺗﺎ ‪ ١٦٠‬ﮐﻴﻠﻮ ﻫﺮﺗﺰ )‪ (Upstream‬ﻭ ﮐﺎﻧﺎﻝ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﺑﺮﺍﯼ ﮐﺎﺭﺑﺮ‪ ،‬ﺩﺍﺭﺍﯼ ﻣﺤﺪﻭﺩﻩ ﺍﯼ ﮐﻪ ﺍﺯ‪ ٢٤٠‬ﮐﻴﻠﻮ ﻫﺮﺗﺰ ﺷﺮﻭﻉ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺣﺪﺍﮐﺜﺮ‬

‫ﺑﺎﻧﺪ ﻓﻮﻕ ﺑﻪ ﻋﻮﺍﻣﻞ ﺗﻔﺎﻭﺗﯽ ﻧﻈﻴﺮ ‪:‬ﻃﻮﻝ ﺧﻂ ‪ ،‬ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺮﮐﺖ ﺗﻠﻔﻨﯽ‬ ‫ﺧﺎﺹ ﻭ ‪...‬ﺑﺴﺘﮕﯽ ﺩﺍﺭﺩ‪ ،‬ﺑﻬﺮﺣﺎﻝ ﺣﺪﺍﮐﺜﺮ ﻣﺤﺪﻭﺩﻩ ﺑﺎﻧﺪ ﻓﻮﻕ ﺍﺯ ‪ ١,٥‬ﻣﮕﺎﻫﺮﺗﺰ ﺗﺠﺎﻭﺯ‬ ‫ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺳﻴﺴﺘﻢ ‪ CAP‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻪ ﮐﺎﻧﺎﻝ ﻓﻮﻕ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ‬

‫ﻣﺮﺑﻮﻃﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ ، DMT‬ﻧﻴﺰ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺑﻪ ﮐﺎﻧﺎﻝ ﻫﺎﯼ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬ﺩﺭ‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻓﻮﻕ ﺍﺯ ﺩﻭ ﮐﺎﻧﺎﻝ ﻣﺠﺰﺍ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﯽ ﮔﺮﺩﺩ‪،DMT .‬‬ ‫ﺩﺍﺩﻩ ﺭﺍ ﺑﻪ ‪ ٢٤٧‬ﮐﺎﻧﺎﻝ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬ﻫﺮ ﮐﺎﻧﺎﻝ ﺩﺍﺭﺍﯼ ﺑﺎﻧﺪ ‪ ٤‬ﮐﻴﻠﻮ ﻫﺮﺗﺰ ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬

‫) ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ﺁﻥ ﺍﺳﺖ ﮐﻪ ﺷﺮﮐﺖ ﺗﻠﻔﻦ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﺧﻂ ﻣﺴﯽ ﻣﻮﺟﻮﺩ ﺭﺍ ﺑﻪ ‪٢٤٧‬‬

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‫ﺧﻂ ‪ ٤‬ﮐﻴﻠﻮ ﻫﺮﺗﺰﯼ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻭ ﻫﺮ ﻳﮏ ﺍﺯ ﺧﻄﻮﻁ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﻳﮏ ﻣﻮﺩﻡ ﻣﺘﺼﻞ ﻧﻤﻮﺩﻩ‬

‫ﺍﺳﺖ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﻫﻤﺰﻣﺎﻥ ﺍﺯ ‪ ٢٤٧‬ﻣﻮﺩﻡ ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﯼ ﺑﺎﻧﺪ ‪ ٤‬ﮐﻴﻠﻮﻫﺮﺗﺰ ﻣﯽ ﺑﺎﺷﻨﺪ(‪ .‬ﻫﺮ‬ ‫ﻳﮏ ﺍﺯ ﮐﺎﻧﺎﻝ ﻫﺎ‪ ،‬ﮐﻨﺘﺮﻝ ﻭ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﮐﻴﻔﻴﺖ ﻳﮏ ﮐﺎﻧﺎﻝ ﺍﻓﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﻴﮕﻨﺎﻝ ﺑﺮ ﺭﻭﯼ‬ ‫ﮐﺎﻧﺎﻝ ﺩﻳﮕﺮ ﺷﻴﻔﺖ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻓﺮﺁﻳﻨﺪ ﺷﻴﻔﺖ ﺩﺍﺩﻥ ﺳﻴﮕﻨﺎ ﻝ ﻫﺎ ﺑﻴﻦ ﮐﺎﻧﺎﻝ ﻫﺎﯼ‬

‫ﻣﺘﻔﺎﻭﺕ ﻭ ﺟﺴﺘﺠﻮ ﺑﺮﺍﯼ ﻳﺎﻓﺘﻦ ﺑﻬﺘﺮﻳﻦ ﮐﺎﻧﺎﻝ ‪ ،‬ﺑﺼﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﺮﺧﯽ ﺍﺯ‬ ‫ﮐﺎﻧﺎﻝ ﻫﺎ ﺑﺼﻮﺭﺕ ﺩﻭ ﻃﺮﻓﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﻧﺪ )ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ( ﮐﻨﺘﺮﻝ ﻭ ﻣﺮﺗﺐ‬

‫ﺳﺎﺯﯼ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﮐﺎﻧﺎﻝ ﻫﺎﯼ ﺩﻭ ﻃﺮﻓﻪ ﻭ ﻧﮕﻬﺪﺍﺭﯼ ﮐﻴﻔﻴﺖ ﻫﺮ ﻳﮏ ﺍﺯ ‪ ٢٤٧‬ﮐﺎﻧﺎﻝ ﻣﻮﺟﻮﺩ‪،‬‬

‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ DMT‬ﺭﺍ ﻧﺴﺒﺖ ﺑﻪ ‪ CAP‬ﺑﻤﺮﺍﺗﺐ ﭘﻴﭽﻴﺪﻩ ﺗﺮ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‬

‫‪ DMT‬ﺩﺍﺭﺍﯼ ﺍﻧﻌﻄﺎﻑ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﯼ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﮐﻴﻔﻴﺖ ﺧﻄﻮﻁ ﻭ ﮐﺎﻧﺎﻝ ﻫﺎ ﯼ ﻣﺮﺑﻮﻃﻪ‬ ‫ﺍﺳﺖ ‪.‬‬

‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﯼ ‪ CAP‬ﻭ‪ DMT‬ﺍﺯ ﺩﻳﺪ ﮐﺎﺭﺑﺮ ﺩﺍﺭﺍﯼ ﻳﮏ ﺷﺒﺎﻫﺖ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﻫﺮ ﺩﻭ ﺣﺎﻟﺖ‬ ‫ﺍﺯ ﻳﮏ ﻓﻴﻠﺘﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﻴﻠﺘﺮ ﻧﻤﻮﺩﻥ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻓﻴﻠﺘﺮﻫﺎﯼ ﻓﻮﻕ‬ ‫ﺍﺯ ﻧﻮﻉ ‪ Low-Pass‬ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻓﻴﻠﺘﺮﻫﺎﯼ ﻓﻮﻕ ﺩﺍﺭﺍﯼ ﺳﺎﺧﺘﺎﺭﯼ ﺳﺎﺩﻩ ﺑﻮﺩﻩ ﻭ ﺗﻤﺎﻡ‬ ‫ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ﺑﺎﻻﺗﺮ ﺍﺯ ﻳﮏ ﻣﺤﺪﻭﺩﻩ ﺭﺍ ﺑﻼﮎ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﻣﮑﺎﻟﻤﺎﺕ ﺻﻮﺗﯽ ﺩﺭ ﻣﺤﺪﻭﺩﻩ‬

‫ﭘﺎﻳﻴﻦ ﺗﺮ ﺍﺯ ‪ ٤‬ﮐﻴﻠﻮ ﻫﺮﺗﺰ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﻧﺪ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻓﻴﻠﺘﺮﻫﺎﯼ ﻓﻮﻕ ﺗﻤﺎﻡ ﺳﻴﮕﻨﺎ ﻝ ﻫﺎﯼ ﺑﺎﻻﺗﺮ‬ ‫ﺍﺯ ﻣﺤﺪﻭﺩﻩ ﻓﻮﻕ ﺭﺍ ﺑﻼﮎ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﺯ ﺗﺪﺍﺧﻞ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ﺩﺍﺩﻩ ﺑﺎ‬ ‫ﻣﮑﺎﻟﻤﺎﺕ ﺗﻠﻔﻨﯽ ﺟﻠﻮﮔﻴﺮﯼ ﺑﻌﻤﻞ ﻣﯽ ﺁﻳﺪ‪.‬‬ ‫ﺗﺠﻬﻴﺰﺍﺕ ‪DSL‬‬

‫‪ ADSL‬ﺍﺯ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﺧﺎﺹ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﻳﮑﯽ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺩﺭ ﻣﺤﻞ ﻣﺸﺘﺮﮐﻴﻦ ﻭ‬ ‫ﺩﺳﺘﮕﺎﻩ ﺩﻳﮕﺮ ﺑﺮﺍﯼ ‪ ، ISP‬ﺷﺮﮐﺖ ﺗﻠﻔﻦ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻧﻬﺎﯼ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ‪، DSL‬‬

‫ﻧﺼﺐ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻣﺤﻞ ﻣﺸﺘﺮﮐﻴﻦ ﺍﺯ ﻳﮏ ﺗﺮﺍﻧﺴﻴﻮﺭ ‪ DSL‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ‬ ‫ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ‪ DSL‬ﺍﺯ ﻳﮏ‪ DSL Access Multiplexer‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‬ ‫‪64‬‬

‫)‪ .(DSLAM‬ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﺍﺗﺼﺎﻻﺕ ﻣﺸﺘﺮﮐﻴﻦ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﺑﻪ ﺗﺸﺮﻳﺢ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﻓﻮﻕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫ﺗﺮﺍﻧﺴﻴﻮﺭ ‪DSL‬‬

‫ﺍﮐﺜﺮ ﻣﺸﺘﺮﮐﻴﻦ ‪ ، DSL‬ﺗﺮﺍﻧﺴﻴﻮﺭ ‪ DSL‬ﺭﺍ ﻣﻮﺩﻡ ‪ DSL‬ﻣﯽ ﻧﺎﻣﻨﺪ‪ .‬ﻣﻬﻨﺪﺳﻴﻦ ﻭ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ‬

‫ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺑﻪ ﺩﺳﺘـﮕﺎﻩ ﻓﻮﻕ ‪ ATU-R‬ﻣﯽ ﮔﻮﻳﻨﺪ‪ .‬ﺻﺮﻓـﻨﻈﺮ ﺍﺯ ﻫﺮ ﻧﺎﻣﯽ ﮐﻪ ﺑﺮﺍﯼ ﺁﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ ،‬ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﻧﻘﻄﻪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﺎﺭﺑﺮ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﺑﻪ ﺧﻂ‬ ‫‪ DSL‬ﺍﺳﺖ‪ .‬ﺗﺮﺍﻧﺴﻴﻮﺭ ﺑﺎ ﺍﺳﺘــﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻫـﺎﯼ ﻣــﺘﻔﺎﻭﺕ ﺑﻪ ﺩﺳـﺘﮕﺎﻩ ﻣﺸﺘﺮﮐﻴﻦ ﻣﺘﺼﻞ‬

‫ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺭﻭﺵ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺗﺼﺎﻻﺕ ‪ USB‬ﻭ ﻳﺎ ﺍﺗﺮﻧﺖ ﺍﺳﺖ‪.‬‬

‫‪DSLAM‬‬ ‫ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺩﺭ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ DSL‬ﻧﺼﺐ ﻭ ﺍﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ‬ ‫ﻣﺒﺘﻨﯽ ﺑﺮ ‪ DSL‬ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪ DSLAM .‬ﺍﺗﺼﺎﻻﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﻌﺪﺍﺩﯼ ﺍﺯ ﻣﺸﺘﺮﮐﻴﻦ‬ ‫ﺭﺍ ﮔﺮﻓﺘﻪ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﻪ ﻳﮏ ﺍﺗﺼﺎﻝ ﺑﺎ ﻇﺮﻓﻴﺖ ﺑﺎﻻ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺗﺒﺪﻳﻞ‬

‫ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ‪ DSLAM‬ﺩﺍﺭﺍﯼ ﺍﻧﻌﻄﺎﻑ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ‬ ‫‪ DSL‬ﻣﺘﻔﺎﻭﺕ ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﻭ ﻣﺪﻭﻻﺳﻴﻮﻥ ﻣﺘﻔﺎﻭﺕ )‪ (Cap,DMT‬ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺩﺭ ﺑﺮﺧﯽ ﺍﺯ ﻣﺪﻝ ﻫﺎﯼ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺻﯽ ﻧﻈﻴﺮ ﺍﺧﺘﺼﺎﺹ ﭘﻮﻳﺎﯼ ﺁﺩﺭﺱ‬ ‫ﻫﺎﯼ ‪ IP‬ﺑﻪ ﻣﺸﺘﺮﮐﻴﻦ‪ ،‬ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬ ‫ﻳﮑﯽ ﺍﺯ ﺗﻔﺎﻭﺕ ﻫﺎﯼ ﻣﻬﻢ ﺑﻴﻦ ‪ ADSL‬ﻭ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ‪ ،‬ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ﻭ ﺭﻓﺘﺎﺭ‬ ‫‪ DSLAM‬ﺍﺳﺖ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﺑﺴﺘﻪ ﺑﺼﻮﺭﺕ ﺍﺷﺘﺮﺍﮐﯽ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫‪65‬‬

‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻳﮑﻪ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ ‪ ،‬ﮐﺎﺭﺁﺋﯽ ﺁﻧﻬﺎ ﺗﻨﺰﻝ ﭘﻴﺪﺍ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ADSL .‬ﺑﺮﺍﯼ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺍﺧﺘﺼﺎﺻﯽ ﺍﻳﺠﺎﺩ ﻭ ﺁﻥ ﺭﺍ ﺑﻪ‬

‫‪ DSLAM‬ﻣﺘﺼﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﮐﺎﺭﺁﺋﯽ ﻣﺮﺑﻮﻃﻪ ﺗﻨﺰﻝ‬ ‫ﭘﻴﺪﺍ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﺗﺎ ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺗﻤﺎﻡ ﻇﺮﻓﻴﺖ ﻣﻮﺟﻮﺩ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﺑﺎ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻧﮑﺮﺩﻩ ﺑﺎﺷﻨﺪ‪ ،‬ﺍﺩﺍﻣﻪ ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻤﺎﻡ ﻇﺮﻓـﻴﺖ‬

‫ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ DSL‬ﻣﯽ ﺗﻮﺍﻧﻨﺪ ﻧﺴﺒﺖ ﺑﻪ ﺍﺭﺗﻘﺎﺀ ﺧﻂ‬ ‫ﺍﺭﺗﺒﺎﻃﯽ ﺍﻳﻨﺘﺮﻧﺖ ﺍﻗﺪﺍﻡ ﺗﺎ ﺗﻤﺎﻡ ﻣﺸﺘﺮﮐﻴﻦ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ‪ DSLAM‬ﺩﺍﺭﺍﯼ ﮐﺎﺭﺁﺋﯽ ﻣﻄﻠﻮﺏ‬ ‫ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﮔﺮﺩﻧﺪ‪.‬‬

‫ﺁﻳﻨﺪﻩ ‪DSL‬‬ ‫‪ ADSL‬ﺑﺎ ﺳﺎﻳﺮ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻈﻴﺮ ﻣﻮﺩﻡ ﻫﺎﯼ‬ ‫ﮐﺎﺑﻠﯽ ﻭ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺭﻗﺎﺑﺖ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺮ ﻃﺒﻖ ﺁﻣﺎﺭ ﺍﺧﺬ ﺷﺪﻩ ﺩﺭ ﺳﺎﻝ ‪،١٩٩٩‬‬

‫ﺑﻴﺶ ﺍﺯ ‪ ٣٣٠,٠٠٠‬ﻣﻨﺰﻝ ﺩﺭ ﺍﻣﺮﻳﮑﺎ ﺍﺯ ‪ DSL‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﺍﻧﺪ‪ .‬ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻣﻮﺩﻡ ﻫـﺎﯼ ﮐﺎﺑﻠﯽ ﺗﺎ ﺳﺎﻝ ‪ ١٩٩٩‬ﺑﻪ ﻣﺮﺯ ‪ ١,٣٥٠,٠٠٠‬ﮐﺎﺭﺑﺮ ﺭﺳﻴﺪﻩ ﺍﺳﺖ‪ .‬ﺑﺮ ﺍﺳﺎﺱ ﭘﻴﺶ‬ ‫ﺑﻴﻨﯽ ﺑﻌﻤﻞ ﺁﻣﺪﻩ ﺗﺎ ﺍﻭﺍﺧﺮ ﺳﺎﻝ ‪ ،٢٠٠٣‬ﺗــﻌﺪﺍﺩ ﻣـــﺸﺘﺮﮐﻴﻦ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑــﻠﯽ ﺑﻪ ﻣﺮﺯ‬ ‫‪ ٨,٩٨٠,٠٠٠‬ﻭ ﻣﺸﺘﺮﮐﻴﻦ ‪ DSL‬ﺑﻪ ‪ ٩,٣٠٠,٠٠٠‬ﺧﻮﺍﻫﺪ ﺭﺳﻴﺪ‪.‬‬

‫ﺳﺮﻋﺖ ‪ ADSL‬ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺣﺪﺍﮐﺜﺮ ‪ ١,٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪ .‬ﺍﺯ ﻟﺤﺎﻅ ﺗﺌﻮﺭﯼ‬ ‫ﺭﺳﻴﺪﻥ ﺑﻪ ﻣﺮﺯ ‪ ٧‬ﻣﮕﺎﺑﺎﻳﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺩﻭﺭ ﺍﺯ ﺩﺳﺘﺮﺱ ﻧﻤﯽ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺗﺤﻘﻴﻘﺎﺕ‬ ‫ﻋﻤﺪﻩ ﺍﯼ ﺻﻮﺭﺕ ﮔﺮﻓﺘﻪ ﻭ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ VDSL‬ﻣﻄﺮﺡ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

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‫‪VDSL‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻃﯽ ﺳﺎﻟﻴﺎﻥ ﺍﺧﻴﺮ‬ ‫ﺑﺸﺪﺕ ﺭﺷﺪ ﺩﺍﺷﺘﻪ ﺍﺳﺖ‪ .‬ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﻭ ﺧﻄﻮﻁ ‪ ADSL‬ﺩﻭ ﺭﻭﻳﮑﺮﺩ ﻣﺘﻔﺎﻭﺕ ﺩﺭ ﺍﻳﻦ‬

‫ﺯﻣﻴﻨﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﯼ ﻫﺎﯼ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﯽ ﮐﺎﺭﺑﺮﺍﻥ ﺭﺍ ﺑﺎ ﺳﺮﻋﺖ ﻣﻄﻠﻮﺏ ﺑﻪ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ﺑﺴﺮﻋﺖ ﺩﺭ ﺣﺎﻝ ﺭﺷﺪ ﺩﺭ ﺗﻤﺎﻣﯽ ﺍﺑﻌﺎﺩ ﺍﺳﺖ‪ .‬ﺗﻠﻮﻳﺰﻳﻮﻥ‬ ‫ﻫﺎﯼ ﺩﻳﺠﻴﺘﺎﻟﯽ ﻭ ﭘﺨﺶ ﺗﺼﺎﻭﻳﺮ ﻭﻳﺪﺋﻮﻳﻲ ﺩﻭ ﮐﺎﺭﺑﺮﺩ ﺟﺪﻳﺪ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻮﺩﻩ ﮐﻪ ﻋﻼﻗﻪ‬

‫ﻣﻨﺪﺍﻥ ﻭ ﻣﺸﺘﺎﻗﺎﻥ ﺯﻳﺎﺩﯼ ﺭﺍ ﺑﻪ ﺧﻮﺩ ﺟﻠﺐ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻓﻮﻕ ﻭ ﺳﺎﻳﺮ‬ ‫ﺧﺪﻣﺎﺕ ﻣﺸﺎﺑﻪ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻴﺎﺯﻣﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﺑﻤﺮﺍﺗﺐ‬ ‫ﺳﺮﻳﻌﺘﺮ ﻧﺴﺒﺖ ﺑﻪ ﻭﺿﻌﻴﺖ ﻓﻌﻠﯽ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﻭ ﻳﺎ ﺧﻄﻮﻁ ‪ ADSL‬ﻋﻠﻴﺮﻏﻢ‬

‫ﺍﺭﺍﺋﻪ ﺳﺮﻋﺖ ﻣﻨﺎﺳﺐ ﺩﺭ ﮐﺎﺭﺑـﺮﺩﻫﺎﺋﯽ ﮐﻪ ﺑﻪ ﺁﻧﻬﺎ ﺍﺷــﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﻓﺎﻗﺪ ﺳﺮﻋﺖ ﻻﺯﻡ‬ ‫ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺍﺧﻴﺮﺍ" ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﺷﺮﮐﺖ ﻫﺎﯼ ﻣﺘﻌﺪﺩﯼ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪Very high bit-rate ( VDSL‬‬ ‫‪ (DSL‬ﺭﺍ ﻣﻄﺮﺡ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﺷﺮﮐﺖ ﻫﺎ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺍﺋﻪ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺩﺭ ﺑﺮﺧﯽ ﺍﺯ‬

‫ﻧﻘﺎﻁ ﮐﺸﻮﺭﺍﻣﺮﻳﮑﺎ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ VDSL .‬ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﺑﺴﻴﺎﺭ ﺑﺎﻻﺋﯽ ﺭﺍ ﺍﺭﺍﺋﻪ ﻭ ﺳﺮﻋﺖ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ‪ ٥٢‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ ‪ .‬ﺳﺮﻋﺖ ﻓﻮﻕ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ‪ ) DSL‬ﺣﺪﺍﮐﺜﺮ ﺳﺮﻋﺖ ‪٨‬‬ ‫ﺗﺎ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ﻭ ﻳﺎ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﺑﺴﻴﺎﺭ ﺑﺎﻻ ﺑﻮﺩﻩ ﻭ ﻗﻄﻌﺎ" ﻧﻘﻄﻪ ﻋﻄﻔﯽ ﺩﺭ ﺯﻣﻴﻨﻪ‬ ‫ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻧﻈﺮ ﺳﺮﻋﺖ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻧﻘﻄﻪ ﻋﻄﻒ ﻗﺒﻠﯽ‪ ،‬ﮔﺬﺭ ﺍﺯ ﻣﺮﺣﻠﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻣﻮﺩﻡ ﻫﺎﯼ ﺑﺎ ﻇﺮﻓﻴﺖ ‪ ٥٦‬ﮐﻴﻠﻮ ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﻪ ‪ broadband‬ﺑﻮﺩ‪.‬‬ ‫‪ ADSL‬ﺍﺯ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﺧﺎﺹ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﻳﮑﯽ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺩﺭ ﻣﺤﻞ ﻣﺸﺘﺮﮐﻴﻦ‬ ‫ﻭ ﺩﺳﺘﮕﺎﻩ ﺩﻳﮕﺮ ﺑﺮﺍﯼ ‪ ،ISP‬ﺷﺮﮐﺖ ﺗﻠﻔﻦ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻧﻬﺎﯼ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ‪،DSL‬‬ ‫ﻧﺼﺐ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻣﺤﻞ ﻣﺸﺘﺮﮐﻴﻦ ﺍﺯ ﻳﮏ ﺗﺮﺍﻧﺴﻴﻮﺭ ‪ DSL‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ‬ ‫ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ‪ DSL‬ﺍﺯ ﻳﮏ ‪ Multiplexer DSL Access‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‬

‫‪ . (DSLAM).‬ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﺍﺗﺼﺎﻻﺕ ﻣﺸﺘﺮﮐﻴﻦ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬ ‫‪67‬‬

‫ﺍﮐﺜﺮ ﻣﺸﺘﺮﮐﻴﻦ ‪ ،DSL‬ﺗﺮﺍﻧﺴﻴﻮﺭ ‪ DSL‬ﺭﺍ ﻣﻮﺩﻡ ‪ DSL‬ﻣﯽ ﻧﺎﻣﻨﺪ‪ .‬ﻣﻬﻨﺪﺳﻴﻦ ﻭ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ‬

‫ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺑﻪ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ‪ ATU-R‬ﻣﯽ ﮔﻮﻳﻨﺪ‪ .‬ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﻫﺮ ﻧﺎﻣﯽ ﮐﻪ ﺑﺮﺍﯼ ﺁﻥ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ ،‬ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﻧﻘﻄﻪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﺎﺭﺑﺮ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﺑﻪ ﺧﻂ‬ ‫‪ DSL‬ﺍﺳﺖ‪ .‬ﺗﺮﺍﻧﺴﻴﻮﺭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﺑﻪ ﺩﺳﺘﮕﺎﻩ ﻣﺸﺘﺮﮐﻴﻦ ﻣﺘﺼﻞ‬

‫ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺭﻭﺵ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺗﺼﺎﻻﺕ ‪ USB‬ﻭ ﻳﺎ ﺍﺗﺮﻧﺖ ﺍﺳﺖ‪.‬‬

‫ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺩﺭ ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ DSL‬ﻧﺼﺐ ﻭ ﺍﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻣﺒﺘﻨﯽ ﺑﺮ‬ ‫‪ DSL‬ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪ DSLAM .‬ﺍﺗﺼﺎﻻﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﻌﺪﺍﺩﯼ ﺍﺯ ﻣﺸﺘﺮﮐﻴﻦ ﺭﺍ ﮔﺮﻓﺘﻪ‬

‫ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﻪ ﻳﮏ ﺍﺗﺼﺎﻝ ﺑﺎ ﻇﺮﻓﻴﺖ ﺑﺎﻻ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ‪ DSLAM‬ﺩﺍﺭﺍﯼ ﺍﻧﻌﻄﺎﻑ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ‪DSL‬‬

‫ﻣﺘﻔﺎﻭﺕ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﻭ ﻣﺪﻭﻻﺳﻴﻮﻥ ﻣﺘﻔﺎﻭﺕ )‪ (Cap,DMT‬ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ‬ ‫ﺑﺮﺧﯽ ﺍﺯ ﻣﺪﻝ ﻫﺎﯼ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺻﯽ ﻧﻈﻴﺮ ﺍﺧﺘﺼﺎﺹ ﭘﻮﻳﺎﯼ ﺁﺩﺭﺱ ﻫﺎﯼ‬ ‫‪ IP‬ﺑﻪ ﻣﺸﺘﺮﮐﻴﻦ‪ ،‬ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬ ‫ﻳﮑﯽ ﺍﺯ ﺗﻔﺎﻭﺕ ﻫﺎﯼ ﻣﻬﻢ ﺑﻴﻦ ‪ ADSL‬ﻭ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ‪ ،‬ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ﻭ ﺭﻓﺘﺎﺭ‬ ‫‪ DSLAM‬ﺍﺳﺖ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﺑﺴﺘﻪ ﺑﺼﻮﺭﺕ ﺍﺷﺘﺮﺍﮐﯽ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻳﮑﻪ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﮐﺎﺭﺁﺋﯽ ﺁﻧﻬﺎ ﺗﻨﺰﻝ ﭘﻴﺪﺍ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ADSL .‬ﺑﺮﺍﯼ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺍﺧﺘﺼﺎﺻﯽ ﺍﻳﺠﺎﺩ ﻭ ﺁﻥ ﺭﺍ ﺑﻪ‬ ‫‪ DSLAM‬ﻣﺘﺼﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﮐﺎﺭﺁﺋﯽ ﻣﺮﺑﻮﻃﻪ ﺗﻨﺰﻝ‬ ‫ﭘﻴﺪﺍ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﺗﺎ ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺗﻤﺎﻡ ﻇﺮﻓﻴﺖ ﻣﻮﺟﻮﺩ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﺑﺎ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻧﮑﺮﺩﻩ ﺑﺎﺷﻨﺪ‪ ،‬ﺍﺩﺍﻣﻪ ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻤﺎﻡ ﻇﺮﻓﻴﺖ ﺧﻂ‬

‫ﺍﺭﺗﺒﺎﻃﯽ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻣﺮﺍﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ DSL‬ﻣﯽ ﺗﻮﺍﻧﻨﺪ ﻧﺴﺒﺖ ﺑﻪ ﺍﺭﺗﻘﺎﺀ ﺧﻂ‬ ‫ﺍﺭﺗﺒﺎﻃﯽ ﺍﻳﻨﺘﺮﻧﺖ ﺍﻗﺪﺍﻡ ﺗﺎ ﺗﻤﺎﻡ ﻣﺸﺘﺮﮐﻴﻦ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ‪ DSLAM‬ﺩﺍﺭﺍﯼ ﮐﺎﺭﺁﺋﯽ ﻣﻄﻠﻮﺏ‬ ‫ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﺳﺮﻋﺖ ‪VDSL‬‬

‫ﻋﻤﻠﮑﺮﺩ ‪ ، VDSL‬ﺩﺭ ﺍﻏﻠﺐ ﻣﻮﺍﺭﺩ ﻣﺸﺎﺑﻪ ‪ ADSL‬ﺍﺳﺖ ‪ .‬ﻋﻠﻴﺮﻏﻢ ﺷﺒﺎﻫﺖ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺧﺘﻼﻓﺎﺕ ﻣﺘﻌﺪﺩﯼ ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ VDSL .‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﺳﺮﻋﺖ ‪ ٥٢‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬

‫ﺛﺎﻧﻴﻪ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﮐﺎﺭﺑﺮ )‪ (Downstream‬ﻭ ‪ ١٦‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬ ‫ﺛﺎﻧﻴﻪ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﮐﺎﺭﺑﺮ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ )‪ (Upstream‬ﺍﺳﺖ‪.‬‬ ‫ﺳﺮﻋﺖ ﻫﺎﯼ ﻓﻮﻕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ ‪ ADSL‬ﺍﺳﺖ‪ .‬ﺩﺭ ‪ ADSL‬ﺣﺪﺍﮐﺜﺮ ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﮐﺎﺭﺑﺮ‪ ٨ ،‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻭ ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮐﺎﺭﺑﺮ ﺑﻪ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ‪ ٨٠٠‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪ VDSL .‬ﺳﺮﻋﺖ ﺑﺎﻻﯼ ﺧﻮﺩ ﺭﺍ ﻣﺪﻳﻮﻥ ﻣﺤﺪﻭﺩﺗﺮ‬ ‫ﺷﺪﻥ ﻓﺎﺻﻠﻪ ﺑﻴﻦ ﻣﺸﺘﺮﮐﻴﻦ ﻭ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺍﺳﺖ ‪ .‬ﺣﺪﺍﮐﺜﺮ ﻣﺴﺎﻓﺖ‬ ‫ﻣﻮﺟﻮﺩ ‪ ٤,٠٠٠‬ﻓﻮﺕ ) ‪ ١,٢٠٠‬ﻣﺘﺮ ( ﺍﺳﺖ‪.‬‬

‫ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺩﺭ ﺣﺎﻝ ﺟﺎﻳﮕﺰﻳﻦ ﻧﻤﻮﺩﻥ ﺍﻏﻠﺐ ﺗﺠﻬﻴﺰﺍﺕ )ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﻐﺬﻳﻪ ﺍﻃﻼﻋﺎﺕ(‬

‫ﺑﻪ ﻓﻴﺒﺮ ﻧﻮﺭﯼ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪Fiber to the (FTTC‬‬ ‫‪ (curb‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺷﺮﮐﺖ ﻫﺎﯼ ﻓﻮﻕ ﻗﺼﺪ ﺩﺍﺭﻧﺪ ﮐﻪ ﺗﻤﺎﻡ ﺧﻄﻮﻁ ﻣﺴﯽ ﻣﻮﺟﻮﺩ ﺭﺍ‬

‫ﺗﺎ ﻣﺤﻠﯽ ﮐﻪ ﺍﺯ ﺁﻧﻬﺎ ﺍﻧﺸﻌﺎﺏ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﻭ ﺑﻪ ﻣﻨﺎﺯﻝ ﻣﺸﺘﺮﮐﻴﻦ ﺗﻮﺯﻳﻊ ﻣﯽ ﮔﺮﺩﺩ‪ ،‬ﺗﻌﻮﻳﺾ‬ ‫ﻧﻤﺎﻳﻨﺪ‪ .‬ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺩﺭ ﺗﻼﺵ ﺑﺮﺍﯼ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺳﻴﺴﺘﻢ ‪Fiber To the‬‬ ‫‪ (FFTN(Neighborhood‬ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺩﺭ ﻋﻮﺽ ﻧﺼﺐ ﮐﺎﺑﻞ ﻓﻴﺒﺮ‬ ‫ﻧﻮﺭﯼ ﺩﺭ ﻫﺮﺧﻴﺎﺑﺎﻥ ‪ FFTN ،‬ﺩﺍﺭﺍﯼ ﻓﻴﺒﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺗﺎ ﺟﻌﺒﻪ ﺍﺗﺼﺎﻻﺕ ) ﺍﻧﺸﻌﺎﺑﺎﺕ ( ﺑﺮﺍﯼ‬ ‫ﻳﮏ ﻫﻤﺴﺎﻳﻪ ) ﻣﺸﺘﺮﮎ ( ﺧﺎﺹ ﺍﺳﺖ‪.‬‬

‫ﺑﺎ ﺍﺍﺳﺘﻘﺮﺍﺭ ﻳﮏ ﺗﺮﺍﻧﺴﻴﻮﺭ ‪ VDSL‬ﺩﺭ ﻣﻨﺰﻝ ﻭ ﻳﮏ ‪ VDSL gateway‬ﺩﺭ ﺟﻌﺒﻪ ﺗﻘﺴﻴﻢ‬ ‫ﺍﺗﺼﺎﻻﺕ‪ ،‬ﻣﺤﺪﻭﺩﻳﺖ ﻓﺎﺻﻠﻪ ﮐﻢ ﺭﻧﮓ ﺧﻮﺍﻫﺪ ﺷﺪ‪ gateway .‬ﺑﺎﻋﺚ ﻣﺮﺍﻗﺒﺖ ﺍﺯ ﺗﺒﺪﻳﻼﺕ‬ ‫ﺁﻧﺎﻟﻮﮒ ﺑﻪ ﺩﻳﺠﻴﺘﺎﻝ ﻭ ﺩﻳﺠﻴﺘﺎﻝ ﺑﻪ ﺁﻧﺎﻟﻮﮒ ﮐﻪ ﺑﺎﻋﺚ ﻏﻴﺮﻓﻌﺎﻝ ﺷﺪﻥ ‪ ADSL‬ﺑﺮ ﺭﻭﯼ ﺧﻄﻮﻁ‬ ‫ﻓﻴﺒﺮ ﻧﻮﺭﯼ ﻣﯽ ﮔﺮﺩﺩ‪ Gateway .‬ﺩﺍﺩﻩ ﻫﺎﯼ ﻭﺭﻭﺩﯼ ﻭ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺍﺯ ﺗﺮﺍﻧﺴﻴﻮﺭ ﺭﺍ ﺑﻪ‬ ‫ﭘﺎﻟﺲ ﻫﺎﯼ ﻧﻮﺭ ﺗﺒﺪﻳﻞ ﺗﺎ ﺯﻣﻴﻨﻪ ﺍﺭﺳﺎﻝ ﺁﻧﻬﺎ ﺍﺯ ﻃﺮﻳﻖ ﻓﻴﺒﺮ ﻧﻮﺭﯼ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺩﺍﺩﻩ ﻫﺎ‬ ‫ﺑﺮﺍﯼ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﺎﺭﺑﺮ ﺍﺭﺳﺎﻝ ﻣﯽ ﮔﺮﺩﻧﺪ) ﺑﺮﮔﺸﺖ ﺩﺍﺩﻩ (‪ Gateway ،‬ﻣﻮﺟﻮﺩ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ‬ ‫‪69‬‬

‫ﻭﺭﻭﺩﯼ ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﯼ ﺭﺍ ﺗﺒﺪﻳﻞ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﯼ ﺗﺮﺍﻧﺴﻴﻮﺭ ﮐﺎﺭﺑﺮ ﺍﺭﺳﺎﻝ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‬ ‫ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﻣﺮﺗﺒﻪ ﺗﮑﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﺩﻳﺪ‪.‬‬

‫‪ ADSL‬ﻭ ‪ VDSL‬ﺻﺮﻓﺎ" ﺩﻭ ﻧﻤﻮﻧﻪ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻁ ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ‪DSL spectrum‬‬ ‫ﻣﯽ ﺑﺎﺷﻨﺪ ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﯽ ﺳﺎﻳﺮ ﻣﺪﻝ ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﮑﻨﻮﻟﻮﮊﯼ ﻓﻮﻕ ﺍﺷﺎﺭﻩ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪.‬‬

‫ﻣﻘﺎﻳﺴﻪ ﺍﻧﻮﺍﻉ ‪DSL‬‬

‫ﻧﻤﻮﻧﻪ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ DSL‬ﺗﺎﮐﻨﻮﻥ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫‪ .(ADSL(Asymmetric DSL‬ﺩﺭﻣﺪﻝ ﻓﻮﻕ ﺑﺪﻟﻴﻞ ﺗﻔﺎﻭﺕ ﺳﺮﻋﺖ ﺩﺭﻳﺎﻓﺖ ﻭ‬ ‫ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻭﺍﮊﻩ " ﻧﺎﻣﺘﻘﺎﺭﻥ " ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻣﺎﻫﻴﺖ ﻋﻤﻠﻴﺎﺕ ﺍﻧﺠﺎﻡ‬ ‫ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺑﮕﻮﻧﻪ ﺍﯼ ﺍﺳﺖ ﮐﻪ ﻫﻤﻮﺍﺭﻩ ﺣﺠﻢ ﺍﻃﻼﻋﺎﺕ ﺩﺭﻳﺎﻓﺘﯽ‬

‫ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﯽ ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ . (HDSL(High bit-rate DSL‬ﺳﺮﻋﺖ ﻣﺪﻝ ﻓﻮﻕ ﺩﺭ ﺣﺪ ﺧﻄﻮﻁ ‪ T1‬ﺍﺳﺖ‬ ‫) ‪ ٥/١‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ‪.‬ﺳﺮﻋﺖ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎ ﺕ ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ‬

‫ﻳﮑﺴﺎﻥ ﺑﻮﺩﻩ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻧﻴﺎﺯ ﺑﻪ ﺩﻭ ﺧﻂ ﻣﺠﺰﺍ ﻧﺴﺒﺖ ﺑﻪ ﺧﻂ ﺗﻠﻔﻦ‬ ‫ﻣﻌﻤﻮﻟﯽ ﻣﻮﺟﻮﺩ ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ . (ISDL(ISDN DSL‬ﻣﺪﻝ ﻓﻮﻕ ﺩﺭ ﺍﺑﺘﺪﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﻩ ﺍﺯ‬ ‫‪ ISDN‬ﻗﺮﺍﺭ ﮔﺮﻓﺖ‪ ISDL .‬ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺳﺎﻳﺮ ﻣﺪﻝ ﻫﺎﯼ ‪ DSL‬ﺩﺍﺭﺍﯼ ﭘﺎﻳﻴﻦ‬ ‫ﺗﺮﻳﻦ ﺳﺮﻋﺖ ﺍﺳﺖ ‪ .‬ﺳﺮﻋﺖ ﺍﻳﻦ ﺧﻄﻮﻁ ‪ ١٤٤‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ )ﺩﻭ ﺟﻬﺖ(‪.‬‬

‫•‬

‫‪ . ( MSDSL(Multirate Symmetric DSL‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ‬ ‫ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻳﮑﺴﺎﻥ ﺍﺳﺖ ‪ .‬ﻧﺮﺥ ﺳﺮﻋﺖ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ‬ ‫ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ ، DSL‬ﺗﻨﻈﻴﻢ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫•‬

‫‪ . (RADSL(Rate Adaptive‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻣﺪﻝ ‪ ADSL‬ﺑﻮﺩﻩ ﻭ ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ‬ ‫ﺑﻪ ﻣﻮﺩﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ﮐﻪ ﺳﺮﻋﺖ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻋﻮﺍﻣﻠﯽ ﻧﻈﻴﺮ ﻣﺴﺎﻓﺖ‬

‫ﻭ ﮐﻴﻔﻴﺖ ﺧﻂ ﺗﻌﻴﻴﻦ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪70‬‬

‫•‬

‫‪ . ( SDLS(Symmetric DSL‬ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻳﮑﺴﺎﻥ‬ ‫ﺍﺳﺖ ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﺑﺮ ﺧﻼﻑ ‪ HDSL‬ﮐﻪ ﺍﺯ ﺩﻭ ﺧﻂ ﻣﺠﺰﺍ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪،‬‬

‫ﺻﺮﻓﺎ" ﺑﻪ ﻳﮏ ﺧﻂ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫•‬

‫‪ . ( VDSL(Very high bit-rate‬ﻣﺪﻝ ﻓﻮﻕ ﺑﺼﻮﺭﺕ "ﻧﺎﻣﺘﻘﺎﺭﻥ " ﺑﻮﺩﻩ ﻭ ﺩﺭ‬

‫•‬

‫‪ .(VoDSL(Voice-over DSL‬ﻳﮏ ﻧﻮﻉ ﺧﺎﺹ ﺍﺯ ‪ IP‬ﺗﻠﻔﻨﯽ ﺍﺳﺖ ‪ .‬ﺩﺭ ﻣﺪﻝ‬

‫ﻣﺴﺎﻓﺖ ﻫﺎﯼ ﮐﻮﺗﺎﻩ ﺑﻬﻤﺮﺍﻩ ﺧﻄﻮﻁ ﻣﺴﯽ ﺗﻠﻔﻦ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫ﻓﻮﻕ ﭼﻨﺪﻳﻦ ﺧﻂ ﺗﻠﻔﻦ ﺗﺮﮐﻴﺐ ﻭ ﺑﻪ ﻳﮏ ﺧﻂ ﺗﻠﻔﻦ ﺗﺒﺪﻳﻞ ﺗﺒﺪﻳﻞ ﻣﯽ ﺷﻮﻧﺪ‪.‬‬

‫ﺟﺪﻭﻝ ﺯﻳﺮ ﻧﻤﻮﻧﻪ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ DSL‬ﺭﺍ ﻧﺸﺎﻥ ﻣﯽ ﺩﻫﺪ‪.‬‬ ‫ﻧﻮﻉ‬

‫ﺣﺪﺍﮐﺜﺮ‬

‫ﺣﺪﺍﮐﺜﺮ ﺳﺮﻋﺖ‬

‫‪DSL‬‬

‫ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ‬

‫ﺩﺭﻳﺎﻓﺖ‬

‫‪ADSL‬‬

‫‪800 Kbps‬‬

‫‪8 Mbps‬‬

‫ﺣﺪﺍﮐﺜﺮ‬ ‫ﻣﺴﺎﻓﺖ‬

‫ﺧﻄﻮﻁ‬

‫ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬

‫ﺍﺯ ﺗﻠﻔﻦ‬

‫‪18,000 ft‬‬ ‫‪(5,500‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪Yes‬‬

‫‪12,000 ft‬‬ ‫‪(3,650 1.54 Mbps 1.54 Mbps HDSL‬‬ ‫)‪m‬‬

‫‪2‬‬

‫‪No‬‬

‫‪IDSL‬‬

‫‪144 Kbps‬‬

‫‪144 Kbps‬‬

‫‪35,000 ft‬‬ ‫‪(10,700‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪No‬‬

‫‪MSDSL‬‬

‫‪2 Mbps‬‬

‫‪2 Mbps‬‬

‫‪29,000 ft‬‬ ‫‪(8,800‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪No‬‬

‫‪RADSL‬‬

‫‪1 Mbps‬‬

‫‪7 Mbps‬‬

‫‪18,000 ft‬‬ ‫‪(5,500‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪Yes‬‬

‫‪SDSL‬‬

‫‪2.3 Mbps‬‬

‫‪2.3 Mbps‬‬

‫‪22,000 ft‬‬ ‫‪(6,700‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪No‬‬

‫‪VDSL‬‬

‫‪16 Mbps‬‬

‫‪52 Mbps‬‬

‫‪4,000 ft‬‬ ‫‪(1,200‬‬ ‫)‪m‬‬

‫‪1‬‬

‫‪Yes‬‬

‫‪71‬‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻣﺘﻌﺪﺩﯼ ﻗﺎﺩﺭ ﺑﻪ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺍﺯ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻣﻌﻤﻮﻟﯽ‪ ،‬ﻣﻮﺩﻡ ﮐﺎﺑﻠﯽ‪ ،‬ﺧﻄﻮﻁ ‪،DSL‬‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻫﻴﭽﮑﺪﺍﻡ ﺍﺯ ﻭﺳﺎﻳﻞ ﺍﺭﺗﺒﺎﻃﯽ ﻓﻮﻕ ﻧﺒﺎﺷﻨﺪ )ﺑﺪﻟﻴﻞ ﻭﺟﻮﺩ ﻣﺴﺎﻓﺖ ﺯﻳﺎﺩ ﺑﻴﻦ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﻩ ﻭ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ (‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ‬

‫ﺍﯼ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺍﺯ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻭ ﻳﺎ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻣﺒﺘﻨﯽ ﺑﺮ‬ ‫ﮐﺎﺑﻞ ﺑﺮﺍﯼ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺳﻴﺴﺘﻢ ﻫﺎ ﺍﺯ ﻳﮏ "ﺑﺸﻘﺎﺏ‬

‫ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ " ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ) ﺩﻭ ﻃﺮﻓﻪ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻣﻌﻤﻮﻻ" ﺩﺭ‬ ‫ﺍﻳﻦ ﻧﻮﻉ ﺳﻴﺴﺘﻢ ﻫﺎ ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﻌﺎﺩﻝ ﻳﮏ ﺩﻫﻢ ﺳﺮﻋﺖ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺍﺳﺖ‪ .‬ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﻭ ﺧﻄﻮﻁ ‪ DSL‬ﻧﺴﺒﺖ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺩﺍﺭﺍﯼ ﺳﺮﻋﺖ‬

‫ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﯼ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺳﺮﻋﺖ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺩﻩ‬ ‫ﺑﺮﺍﺑﺮ ﺳﺮﻋﺖ ﻳﮏ ﻣﻮﺩﻡ ﻣﻌﻤﻮﻟﯽ ﺍﺳﺖ‪.‬‬ ‫ﻣﻮﺳﺴﺎﺕ ﻭ ﺷﺮﮐﺖ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﺗﺎﮐﻨﻮﻥ ﺳﺮﻭﻳﺲ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻋﻼﻗﻪ‬ ‫ﻣﻨﺪﺍﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﻨﺪ‪ Teledesic, StarBand,Pegasus Express .‬ﻭ‬ ‫‪ Tachyon‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺍﺯ ﺷﺮﮐﺖ ﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺑﺼﻮﺭﺕ‬ ‫ﺩﻭ ﻃﺮﻓﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ‪ Tachyon‬ﺩﺭ ﺍﻣﺮﻳﮑﺎ‪ ،‬ﺍﺭﻭﭘﺎﯼ ﻏﺮﺑﯽ ﻭ‬ ‫ﻣﮑﺰﻳﮏ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ ‪ Pegasus Express .‬ﻧﺴﺨﻪ ﺩﻭ ﻃﺮﻓﻪ ‪ DirectPC‬ﺍﺳﺖ‪.‬‬ ‫ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺩﻭ ﻃﺮﻓﻪ ﺍﺯ ﻋﻨﺎﺻﺮ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ ‪:‬‬ ‫•‬

‫ﻳﮏ "ﺑﺸﻘﺎﺏ " )‪ (Dish‬ﺑﺎ ﺍﺑﻌﺎﺩ ﺩﻭ ﻭ ﻳﺎ ﺳﻪ ﻓﻮﺕ‬

‫•‬

‫ﺩﻭ ﻋﺪﺩ ﻣﻮﺩﻡ ) ‪( Uplink,downlink‬‬

‫•‬

‫ﮐﺎﺑﻞ ﻫﺎﯼ ﮐﻮﺍﮐﺴﻴﺎﻝ ﺑﻴﻦ ﺑﺸﻘﺎﺏ ﻭ ﻣﻮﺩﻡ‬

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‫ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﯼ ﺩﻭ ﻃﺮﻓﻪ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ IP multicasting‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﺩﺭ‬

‫ﺍﻳﻦ ﺣﺎﻟﺖ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ‪ ٥,٠٠٠‬ﮐﺎﻧﺎﻝ ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺻﺮﻓﺎ" ﻳﮏ ﻣﺎﻫﻮﺍﺭﻩ‬ ‫ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪ ، IP multicasting .‬ﺩﺍﺩﻩ ﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺍﺯ ﻳﮏ ﻧﻘﻄﻪ ﺑﻪ ﭼﻨﺪﻳﻦ‬ ‫ﻧﻘﻄﻪ ﻭ ﺑﺼﻮﺭﺕ ﻓﺸﺮﺩﻩ‪ ،‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ) ﺩﺭ ﻳﮏ ﺯﻣﺎﻥ (‪ .‬ﺑﺎ ﻓﺸﺮﺩﻩ ﺳﺎﺯﯼ ﺍﻃﻼﻋﺎﺕ‪،‬‬ ‫ﺣﺠﻢ ﺩﺍﺩﻩ ﻫﺎ ﮐﺎﻫﺶ ﻭ ﺍﺯ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﻣﻮﺟﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﺑﻬﻴﻨﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺩﺭ ﺳﻴﺴﺘﻢ ‪ ) DirectPC‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ‪ ، (DirectTV‬ﮐﺎﺭﺑﺮﺍﻥ ﻫﻤﭽﻨﺎﻥ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ‬ ‫ﻳﮏ ‪ ISP‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﯽ ﺑﺎﻳﺴﺖ‬ ‫ﺑﺎ ‪ ISP‬ﺗﻤﺎﺱ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫‪VOIP‬‬ ‫‪ IP‬ﺗﻠﻔﻨﯽ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﮑﺎﻟﻤﺎﺕ ﺗﻠﻔــﻨﯽ ﺑﺮ ﺭﻭﯼ ﻳﮏ ﺷﺒـﮑﻪ ﻣﺒﺘﻨﯽ ﺑﺮ ﺩﺍﺩﻩ ﺍﺳﺖ‪ .‬ﺑﻪ‬

‫ﻧﮑﻨﻮﻟﻮﮊﯼ ﻓﻮﻕ ‪ (Voice-over IP(VoIP‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﯽ ﺷﻮﺩ‪ .‬ﺍﻣﺮﻭﺯﻩ ﻣﮑﺎﻟﻤﺎﺕ ﮔﺴﺘﺮﺩﻩ‬ ‫ﺍﯼ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﻫﺎﯼ ﻣﺒﺘﻨﯽ ﺑﺮ ﺩﺍﺩﻩ ) ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﻧﺖ ( ﺍﻧﺠﺎﻡ ﻣﯽ ﺷﻮﺩ‪.‬‬ ‫‪Circuit Switching‬‬ ‫ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﻠﻔﻦ ﺑﻴﺶ ﺍﺯ ﻳﮑﺼﺪ ﺳﺎﻝ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺗﮑــﻨﻮﻟﻮﮊﯼ‬

‫‪Circuit‬‬

‫‪ Switching‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺑﻤﺤﺾ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒـــﺎﻁ ﺑﻴﻦ ﺩﻭ ﻧﻔﺮ‪،‬‬ ‫ﺩﺭ ﺗﻤﺎﻡ ﻣﺪﺕ ﺯﻣﺎﻥ ﻣﮑﺎﻟﻤﻪ ﻳﮏ ﻣﺪﺍﺭ ﺍﺧﺘﺼﺎﺻﯽ ﺑﺮﺍﯼ ﺁﻧﻬﺎ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﺪﻳﻦ‬

‫ﺗﺮﺗﻴﺐ ﺑﺮﺍﯼ ﺩﻭ ﻧﻘﻄﻪ ﻣﺮﺑﻮﻃﻪ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺩﻭ ﺳﻮﻳﻪ ﺍﻳﺠﺎﺩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻳﮏ‬ ‫ﻣﮑﺎﻟﻤﻪ ﺻﻮﺗﯽ ﺑﻪ ﺻﻮﺭﺕ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﭘﺲ ﺍﺯ ﺑﺮﺩﺍﺷﺘﻦ ﮔﻮﺷﯽ ﺗﻠﻔﻦ ﻳﮏ ﺑﻮﻕ ﺷﻨﻴﺪﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﻮﻕ ﻓﻮﻕ ﺑﻤﻨﺰﻟﻪ ﺑﺮﻗﺮﺍﺭﯼ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺷﺮﮐﺖ ﺗﻠﻔﻦ ) ﻣﺮﮐﺰ ﻣﺮﺑﻮﻃﻪ ( ﺍﺳﺖ‪.‬‬

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‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻴﺴﺘﻢ ﺗﻠﻔﻦ ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺷﻤﺎﺭﻩ ﮔﻴﺮﯼ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫ﺍﺭﺗﺒﺎﻁ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺯ ﻃﺮﻳﻖ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ ﺳﻮﺋﻴﺞ ﻫﺎ ﻋﺒﻮﺭ ﺩﺍﺩﻩ ﺷﺪﻩ ﺗﺎ ﺑﻪ ﻣﺨﺎﻃﺐ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺳﺪ‪.‬‬

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‫ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺗﻠﻔﻦ ﺷﻤﺎ ﻭ ﻣﺨﺎﻃﺐ ﺑﺮﻗﺮﺍﺭ ﻭ ﻳﮏ ﻣﺪﺍﺭ ﻓﻌﺎﻝ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

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‫ﻣﮑﺎﻟﻤﻪ ﺑﺎ ﻣﺨﺎﻃﺐ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ ﻣﺪﺕ ﺯﻣﺎﻥ ﺩﻟﺨﻮﺍﻩ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﻗﻄﻊ ﻣﮑﺎﻟﻤﻪ ‪ ،‬ﻣﺪﺍﺭ ﻓﻌﺎﻝ ﺷﺪﻩ ﺑﻴﻦ ﺷﻤﺎ ﻭ ﻣﺨﺎﻃﺐ ﻏﻴﺮ ﻓﻌﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻓﺮﺽ ﮐﻨﻴﺪ ﻣﺪﺕ ﺯﻣﺎﻥ ﻣﮑﺎﻟﻤﻪ ﺷﻤﺎ ﺩﻩ ﺩﻗﻴﻘﻪ ﺑﺎﺷﺪ ‪ ،‬ﺩﺭ ﻃﻮﻝ ﻣﺪﺕ ﺯﻣﺎﻥ ﻓﻮﻕ ﻣﺪﺍﺭ ﺍﻳﺠﺎﺩ‬

‫ﺷﺪﻩ ﺑﻴﻦ ﺩﻭ ﺗﻠﻔﻦ ﺑﺼﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﻓﻌﺎﻝ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻗﺪﻳﻤﯽ ﻣﺨﺎﺑﺮﺍﺗﯽ‪،‬‬

‫ﻣﮑﺎﻟﻤﻪ ﺗﻠﻔﻨﯽ ﺑﺎ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺛﺎﺑﺖ ‪ ٦٤‬ﮐﻴﻠﻮ ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻭ ﻳﺎ ‪ ١٠٢٤‬ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬ ‫ﺩﺭ ﻫﺮ ﺟﻬﺖ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﺮﻓﺖ ) ﻣﺠﻤﻮﻉ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ‪ ١٢٨‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ‪.‬ﺑﺎ‬

‫ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺩﺭ ﻫﺮ ﮐﻴﻠﻮﺑﺎﻳﺖ‪ ،‬ﻫﺸﺖ ﮐﻴﻠﻮﺑﻴﺖ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ‪ ١٦‬ﮐﻴﻠﻮ‬ ‫ﺑﺎﻳﺖ ﻭ ﻳﺎ ﺩﺭ ﻫﺮ ﺩﻗﻴﻘﻪ ‪ ٩٦٠‬ﮐﻴﻠﻮﺑﺎﻳﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻝ ﻣﯽ ﮔﺮﺩﺩ) ﺯﻣﺎﻧﯽ ﮐﻪ ﻣﺪﺍﺭ ﻓﻌﺎﻝ‬ ‫ﺍﺳﺖ ( ‪.‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭ ﻣﺪﺕ ﺯﻣﺎﻥ ﺩﻩ ﺩﻗﻴﻘﻪ ﺍﺭﺗﺒﺎﻁ ﺗﻠﻔﻨﯽ ‪ ،‬ﻣﺠﻤﻮﻉ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻝ ﺷﺪﻩ‬ ‫‪ ٩٦٠٠‬ﮐﻴﻠﻮ ﺑﺎﻳﺖ ) ‪ ٩/٤‬ﻣﮕﺎﺑﺎﻳﺖ ( ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺩﺭ ﻳﮏ ﻣﮑﺎﻟﻤﻪ ﺗﻠﻔﻨﯽ ﺍﮐﺜﺮ ﺩﺍﺩﻩ ﻫﺎﯼ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺑﻴﻬﻮﺩﻩ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺯﻣﺎﻧﯽ ﮐﻪ ﺷﻤﺎ ﺣﺮﻑ‬ ‫ﻣﯽ ﺯﻧﻴﺪ‪ ،‬ﻣﺨﺎﻃﺐ ﺻﺮﻓﺎ" ﮔﻮﺵ ﻣﯽ ﺩﻫﺪ‪ .‬ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﯽ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﻫﺮ ﻣﻘﻄﻊ ﺯﻣﺎﻧﯽ‪،‬‬ ‫ﺍﺯﻧﺼﻒ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﺑﻴﺸﺘﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﯽ ﮔﺮﺩﺩ‪ ) .‬ﺳﮑﻮﺕ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﺧﻂ ﺩﺭ ﻣﺪﺕ‬

‫ﺯﻣﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺯﻳﺎﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ( ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺣﺠﻢ ﺍﻃﻼﻋــــﺎﺕ ﺍﺭﺳﺎﻝ ﺷﺪﻩ‪،‬‬ ‫ﺑﻪ ‪ ٤/٧‬ﻣﮕﺎﺑﺎﻳﺖ ﺗﻨﺰﻝ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫ﺷﺒﮑﻪ ﻫﺎﯼ ﻣﺒﺘﻨﯽ ﺑﺮ ﺩﺍﺩﻩ ﺍﺯ ﺭﻭﺵ ‪ Circuit switching‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﮑﺮﺩﻩ ﻭ ﺩﺭ ﻣﻘﺎﺑﻞ‪،‬‬ ‫ﺭﻭﺵ ‪ Packet Switching‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫‪Packet Switching‬‬ ‫ﺩﺭ ﺭﻭﺵ ‪ Packet Switching‬ﺑﺮ ﺧﻼﻑ ‪ Switching Circuit‬ﮐﻪ‬

‫ﺑﺼﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﻓﻌﺎﻝ ﻧﮕﻪ ﻣﯽ ﺩﺍﺭﺩ‪ ،‬ﺻﺮﻓﺎ" ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ) ﻳﮏ‬ ‫ﺑﺨﺶ ﮐﻮﭼﮏ ﺩﺍﺩﻩ ﮐﻪ ﺑﻪ ﺁﻥ ‪ packet‬ﮔﻔﺘﻪ ﻣﯽ ﺷﻮﺩ ( ﺍﺭﺗﺒﺎﻁ ﻓﻌﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﻓﺮﺳﺘﻨﺪﻩ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ ‪ Packet‬ﺗﻘﺴﻴﻢ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﯼ‬ ‫ﺍﻃﻼﻋﺎﺗﯽ ﺁﺩﺭﺱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪ .‬ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ‬ ‫ﺑﺴﺘﻪ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﻠﺤﻖ ﺗﺎ ﺍﻃﻼﻋﺎﺕ ﺍﻭﻟﻴﻪ ﺑﻮﺟﻮﺩ ﺁﻳﻨﺪ‪.‬‬

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‫ﺭﻭﺵ ﻓﻮﻕ ﺑﺴﻴﺎﺭ ﮐﺎﺭﺁ ﺑﻮﺩﻩ ﻭ ﺯﻣﺎﻥ ﻓﻌﺎﻝ ﺑﻮﺩﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺭﺍ ﺑﻪ ﺣﺪﺍﻗﻞ‬

‫ﻣﻘﺪﺍﺭ ﺧﻮﺩ ﻣﯽ ﺭﺳﺎﻧﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﺷﺒﮑﻪ ﻧﻴﺰ ﮐﺎﻫﺶ ﺧﻮﺍﻫﺪ‬ ‫ﻳﺎﻓﺖ ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻗﺎﺩﺭ ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﻭ ﻳﺎ‬ ‫ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﯼ ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻧﻴﺰ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

‫ﺗﮑﻨﻮﻟﻮﮊﯼ ‪ VoIP‬ﺍﺯ ﺭﻭﺵ ‪ Packet Switching‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮐﻨﺪ‪ .‬ﺑﺎﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ‬

‫ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﭼﻨﺪﻳﻦ ﻣﮑﺎﻟﻤﻪ ﺗﻠﻔﻨﯽ ﻓﺮﺍﻫﻢ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، PSTN‬ﻳﮏ‬ ‫ﻣﮑﺎﻟﻤﻪ ﺩﻩ ﺩﻗﻴﻘﻪ ﺍﯼ ‪ ،‬ﺩﻩ ﺩﻗﻴﻘﻪ ﮐﺎﻣﻞ ﺍﺯ ﺯﻣﺎﻥ ﺍﻧﺘﻘﺎﻝ ﺑﺎ ﻧﺮﺥ ‪ ١٢٨‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺭﺍ ﺍﺷﻐﺎﻝ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺭﻭﺵ ‪ ، VoIP‬ﻣﮑﺎﻟﻤﻪ ﺩﻩ ﺩﻗﻴﻘﻪ ﺍﯼ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺻﺮﻓﺎ" ‪ ٥/٣‬ﺩﻗﻴﻘﻪ ﺯﻣﺎﻥ‬

‫ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﺑﺎ ﻧﺮﺥ ‪ ٦٤‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺷﻐﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ‪ ٦٤‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ‬ ‫ﺛﺎﻧﻴﻪ ﺑﺮﺍﯼ ﻣﺪﺕ ‪ ٥/٣‬ﺩﻗﻴﻘﻪ ‪ ،‬ﻭ ‪ ١٢٨‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﺮﺍﯼ ﺯﻣﺎﻥ ﺑﺎﻗﻴﻤﺎﻧﺪﻩ ‪ ٦/ ٥‬ﺁﺯﺍﺩ‬ ‫ﺧﻮﺍﻫﺪ ﻣﺎﻧﺪ‪.‬‬

‫ﻓﺮﺽ ﮐﻨﻴﺪ ﮐﻪ ﺷﺮﮐﺖ ﺷﻤﺎ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻤﻨﻄﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ‪ VoIP‬ﺭﺍ‬ ‫ﺧﺮﻳﺪﺍﺭﯼ ﻭ ﻧﺼﺐ ﮐﺮﺩﻩ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺻﺪﻫﺎ ﺗﻠﻔﻦ ﻭ ﻳﮏ ‪Private (PBX‬‬ ‫‪ (branch exchange‬ﻧﻴﺰ ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ ‪ PBX .‬ﺳﻮﺋﻴﭽﯽ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻤﻨﻈﻮﺭ‬

‫ﺍﺭﺗﺒﺎﻁ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ ﺗﻠﻔﻦ ﻫﺎ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻭ ﺑﻪ ﻳﮏ ﻳﺎ ﭼﻨﺪﻳﻦ ﺧﻂ ﺧﺎﺭﺝ ﺍﺯ ﺷﺮﮐﺖ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻣﺜﺎﻝ ﻓﻮﻕ ‪ PBX‬ﺑﺼﻮﺭﺕ ﻳﮏ ‪ gateway‬ﺍﺳﺖ‪.‬‬

‫ﺍﺯ ‪ gateway‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺩﻭ ﺷﺒﮑﻪ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻴﮕﺮﺩﺩ‪ PBX .‬ﻳﮏ ‪ Gateway‬ﺍﺳﺖ ‪ ).‬ﭼﻮﻥ ﺳﻴﮕﻨﺎﻝ ﻫﺎﯼ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪circuit-‬‬

‫‪ switching‬ﻫﺮ ﻳﮏ ﺍﺯ ﺗﻠﻔﻦ ﻫﺎ ﺭﺍ ﺑﻪ ﺩﺍﺩﻩ ﻫﺎﯼ ﺩﻳﺠﻴﺘﺎﻝ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ IP‬ﻭ ‪ Packet Switching‬ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﺪ(‪.‬‬ ‫ﺭﻭﺵ ﺑﺮﻗﺮﺍﺭﯼ ﻳﮏ ﻣﮑﺎﻟﻤﻪ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺷﺒﮑﻪ ‪ Packet-Switching‬ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫‪ VoIP‬ﺑﺼﻮﺭﺕ ﺯﻳﺮ ﺍﺳﺖ ‪:‬‬ ‫•‬

‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺭﺍ ﻓﻌﺎﻝ ﺗﺎ ﺍﺯ ﻃﺮﻳﻖ ﺁﻥ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺑﺮﺍﯼ ‪ PBX‬ﺍﺭﺳﺎﻝ ﮔﺮﺩﺩ‪.‬‬

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‫‪ PBX‬ﺳﻴﮕﻨﺎﻝ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﻳﮏ ﺑﻮﻕ ﺁﺯﺍﺩ ﺭﺍ ﺑﺮﺍﯼ ﻓﺮﺳﺘﻨﺪﻩ ﺍﺭﺳﺎﻝ ﻣﯽ ﺩﺍﺭﺩ‪.‬‬ ‫‪76‬‬

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‫ﻓﺮﺳﺘﻨﺪﻩ ﺍﻗﺪﺍﻡ ﺑﻪ ﺷﻤﺎﺭﻩ ﮔﻴﺮﯼ ﺗﻠﻔﻦ ﻣﺨﺎﻃﺐ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺷﻤﺎﺭﻩ ﻓﻮﻕ ﺩﺭ‬

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‫ﭘﺲ ﺍﺯ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺷﻤﺎﺭﻩ ﺗﻮﺳﻂ ﻓﺮﺳﺘﻨﺪﻩ‪ PBX ،‬ﺑﻤﻨﻈﻮﺭ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ‬

‫ﺍﺩﺍﻣﻪ ﺗﻮﺳﻂ ‪ PBX‬ﺑﺼﻮﺭﺕ ﻣﻮﻗﺖ ﺫﺧﻴﺮﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫ﻓﺮﻣﺖ‪ ،‬ﺁﻥ ﺭﺍ ﺑﺮﺭﺳﯽ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫‪ PBX‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺠﻮﻩ ﺗﻄﺒﻴﻖ ﺷﻤﺎﺭﻩ ﺩﺭﻳﺎﻓﺘﯽ ﺑﺎ ﺷﺨﺺ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻗﺪﺍﻣﺎﺕ ﻻﺯﻡ ﺭﺍ‬ ‫ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭﻓﺮﺁﻳﻨﺪ ﺗﻄﺒﻴﻖ‪ ،‬ﺷﻤﺎﺭﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﺁﺩﺭﺱ ‪ IP‬ﺩﺳﺘﮕﺎﻩ ﺩﻳﮕﺮ ﮐﻪ‬ ‫"ﻣﻴﺰﺑﺎﻥ ‪ "IP‬ﻧﺎﻣﻴﺪﻩ ﻣﯽ ﮔﺮﺩﺩ‪ ،‬ﻣﻠﺤﻖ ﻣﯽ ﮔﺮﺩﺩ‪" .‬ﻣﻴﺰﺑﺎﻥ ‪ "IP‬ﻋﻤﻼ" ﻳﮏ ‪PBX‬‬ ‫ﺩﻳﺠﻴﺘﺎﻟﯽ ﺩﻳﮕﺮ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﺳﻴﺘﻢ ﺗﻠﻔﻦ ﻣﺤﻠﯽ ﮐﻪ ﺑﺎ ﺁﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﺷﺪﻩ ‪ ،‬ﻧﺼﺐ‬

‫ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩ ﺧﺎﺻﯽ ﮐﻪ ﻣﺨﺎﻃﺐ ﺍﺯ ﻳﮏ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ‪ VoIP‬ﻣﺒﺘﻨﯽ ﺑﺮ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ ‪" ،‬ﻣﻴﺰﺑﺎﻥ ‪ ، "IP‬ﺳﻴﺴﺘﻤﯽ ﺍﺳﺖ ﮐﻪ ﻗﺼﺪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﺎ ﺁﻥ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬ ‫•‬

‫ﻳﮏ ‪ session‬ﺑﻴﻦ ‪ PBX‬ﺍﺩﺍﺭﻩ ﺗﻤﺎﺱ ﮔﻴﺮﻧﺪﻩ ﻭ "ﻣﻴﺰﺑﺎﻥ ‪ "IP‬ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻫﺮ‬ ‫ﺳﻴﺴﺘﻢ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎ یﻤﺸﺎﺑﻪ ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺳﻴﺴﺘﻢ ﻫﺎ ﺩﻭ ﮐﺎﻧﺎﻝ ﺑﺮﺍﯼ ﻫﺮ ﺟﻬﺖ ﺭﺍ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬

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‫ﻣﮑﺎﻟﻤﻪ ﺑﻪ ﻣﺪﺕ ﺯﻣﺎﻥ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪.‬ﺩﺭ ﺯﻣﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﻣﮑﺎﻟﻤﻪ‪PBX ،‬‬ ‫ﺷﺮﮐﺖ ﺷﻤﺎ ﻭ ﻣﻴﺰﺑﺎﻥ ‪ IP‬ﻣﺨﺎﻃﺐ‪ ،‬ﺑﺴﺘﻪ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ ﺭﺍ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺩﺭﻳﺎﻓﺖ‬ ‫ﻣﯽ ﺩﺍﺭﻧﺪ‪.‬‬

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‫ﻣﮑﺎﻟﻤﻪ ﺑﻪ ﺍﺗﻤﺎﻡ ﺭﺳﻴﺪﻩ ﻭ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻏﻴﺮﻓﻌﺎﻝ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﻗﻄﻊ ﺍﺭﺗﺒﺎﻁ ‪ ،‬ﻣﺪﺍﺭ) ﺍﺭﺗﺒﺎﻁ ( ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺗﻠﻔﻦ ﺗﻤﺎﺱ ﮔﻴﺮﻧﺪﻩ ﻭ ‪ PBX‬ﺁﺯﺍﺩ‬ ‫ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

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‫‪ PBX‬ﺳﻴﮕﻨﺎﻟﯽ ﺭﺍ ﺑﺮﺍﯼ ﻣﻴﺰﺑﺎﻥ ‪ IP‬ﺍﺭﺳﺎﻝ ﻭ ﺧﺎﺗﻤﻪ ﻣﮑﺎﻟﻤﻪ ﺭﺍ ﺍﻋﻼﻡ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﭘﺲ ﺍﺯ ﺍﺗﻤﺎﻡ ‪ ، session‬ﺩﺳﺘﮕﺎﻩ ‪ PBX‬ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﺗﻄﺒﻴﻖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺑﻪ "ﻣﻴﺰﺑﺎﻥ‬ ‫‪ "IP‬ﺭﺍ ﺍﺯ ﺣﺎﻓﻈﻪ ﺧﻮﺩ ﭘﺎﮎ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﻃﺮﻳﻖ ﺗﻠﻔﻦ ﺑﺎ ﺩﺳﺘﮕﺎﻫﻬﺎﺋﯽ ﻧﻈﻴﺮ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﻃﻮﻝ ﻳﮏ‬

‫ﺷﺒﮑﻪ‪ ،‬ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﻣﺸﺘﺮﮎ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ‬

‫ﺍﺯ ﺩﻭ ﭘﺮﻭﺗﮑﻞ ﻋﻤﺪﻩ ﺑﺮﺍﯼ ‪ VoIP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﯼ ﻓﻮﻕ ﺭﻭﺵ ﻫﺎﯼ ﻣﺮﺑﻮﻁ‬

‫ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﻣﺘﻔﺎﻭﺕ ﺍﺯ ﻃﺮﻳﻖ ‪ VoIP‬ﺭﺍ ﻣﺸﺨﺺ ﻭ ‪ Codec‬ﻫﺎﯼ ﺻﻮﺗﯽ ﺭﺍ‬ ‫ﻧﻴﺰ ﺗﻌﻴﻴﻦ ﻣﯽ ﻧﻤﺎﻳﺪ‪" .‬ﮐﺪﮎ " ﺍﺯ ﺗﻠﻔﻴﻖ ﺩﻭ ﻭﺍﮊﻩ ‪ Code‬ﻭ ‪ Decode‬ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﮐﺪﮎ ‪ ،‬ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺻﻮﺗﯽ ﺭﺍ ﺑﻪ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺩﻳﺠﻴﺘﺎﻟﯽ ﻓﺸﺮﺩﻩ ﺷﺪﻩ ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺍﻭﻟﻴﻦ ﭘﺮﻭﺗﮑﻞ ‪ H.323‬ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ‬ ‫) ‪ ITU(International Telecommunication Union‬ﺍﺳﺖ‪ H.323 .‬ﻳﮏ‬ ‫ﭘﺮﻭﺗﮑﻞ ﭘﻴﺸﺮﻓﺘﻪ ﻭ ﭘﻴﭽﻴﺪﻩ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻣﺸﺨﺼﺎﺕ ﻻﺯﻡ ﺑﺮﺍﯼ ﻭﻳﺪﺋﻮﮐﻨﻔﺮﺍﻧﺲ ﻫﺎﯼ‬

‫ﻣﺤﺎﻭﺭﻩ ﺍﯼ ﻭ ﺍﺷﻨﺘﺮﺍﮎ ﺩﺍﺩﻩ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﺻﻮﺗﯽ ﻧﻈﻴﺮ ‪ IP‬ﺗﻠﻔﻨﯽ ﺭﺍ ﺗﻌﺮﻳﻒ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪ H.323‬ﺩﺍﺭﺍﯼ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺑﻮﺩﻩ ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﯼ ﮐﺎﺭﺑﺮﺩ ﺧﺎﺹ‬ ‫ﺧﻮﺩ ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪H.323 Protocol‬‬ ‫‪Video‬‬ ‫‪H.261‬‬ ‫‪H.263‬‬

‫‪Audio‬‬

‫‪Data‬‬

‫‪T.122 G.711‬‬ ‫‪T.124 G.722‬‬ ‫‪T.125 G.723.1‬‬ ‫‪T.126 G.728‬‬ ‫‪T.127 G.729‬‬

‫‪Transport‬‬ ‫‪H.225‬‬ ‫‪H.235‬‬ ‫‪H.245‬‬ ‫‪H.450.1‬‬ ‫‪H.450.2‬‬ ‫‪H.450.3‬‬ ‫‪RTP‬‬ ‫‪X.224.0‬‬

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‫ﺧﻴﺮﺍ" ﭘﺮﻭﺗﮑﻞ ﺩﻳﮕﺮﯼ ﺑﺎ ﻧﺎﻡ ‪ (session Initiation Protocol(SIP‬ﺗﻮﺳﻂ ‪IETF‬‬

‫ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪ SIP.‬ﻧﺴﺒﺖ ﺑﻪ ‪ H.323‬ﺩﺍﺭﺍﯼ ﮐﺎﺭﺍﺋﯽ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﯼ ﺑﻮﺩﻩ ﻭ ﺻﺮﻓﺎ"‬ ‫ﺑﺮﺍﯼ ‪ IP‬ﺗﻠﻔﻨﯽ ﻃﺮﺍﺣﯽ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﺭﻭﺵ ﻫﺎﯼ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪VoIP‬‬ ‫ﺑﺮﺍﯼ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، VoIP‬ﭼﻬﺎﺭ ﺣﺎﻟﺖ ﻣﺘﻔﺎﻭﺕ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪:‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ .‬ﺳﺎﺩﻩ ﺗــﺮﻳﻦ ﺭﻭﺵ ﺍﺳــﺘﻔﺎﺩﻩ ﺍﺯ ‪ VoIP‬ﺍﺳﺖ‪ .‬ﺷﺮﮐﺖ ﻫﺎﯼ‬ ‫ﻣﺘﻌﺪﺩﯼ‪ ،‬ﺧﺪﻣﺎﺕ ﻓﻮﻕ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﺩﻫﻨﺪ‪ .‬ﺑﺮﺍﯼ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﺑﻪ ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬ ‫ﻣﺮﺑﻮﻃﻪ‪ ،‬ﻣﻴــﮑﺮﻭﻓﻦ‪ ،‬ﺑﻠــﻨﺪﮔﻮ‪ ،‬ﮐﺎﺭﺕ ﺻﺪﺍ ﻭ ﺧﻂ ﺍﺭﺗﺒﺎﻃﯽ ﺑﺎ ﺳﺮﻋﺖ ﻣﻨﺎﺳﺐ‬ ‫) ﺧﻄﻮﻁ ‪ DSL‬ﻭ ﻳﺎ ﻣﻮﺩﻡ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ( ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ MSN Explorer .‬ﻳﮏ‬

‫ﻧﻤﻮﻧﻪ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺗﻠﻔﻦ ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﻣﯽ ﺗﻮﺍﻥ ﺍﺯ ﻃﺮﻳﻖ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺎ ﻫﺮ‬ ‫ﺷﺨﺺ ﮐﻪ ﺩﺍﺭﺍﯼ ﻳﮏ ﺧﻂ ﺗﻠﻔﻦ ﺍﺳﺖ‪ ،‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﮐﺮﺩ‪ .‬ﺑﺮﺍﯼ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ‬

‫ﻓﻮﻕ ﺑﻪ ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻓﻮﻕ ﺍﻏﻠﺐ‬

‫ﺑﺼﻮﺭﺕ ﺭﺍﻳﮕﺎﻥ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﻫﺰﻳﻨﻪ ﻣﮑﺎﻟﻤﺎﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ‪،‬‬

‫ﺑﻤﺮﺍﺗﺐ ﭘﺎﻳﻴﻦ ﺗﺮ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻗﺪﻳﻤﯽ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺗﻠﻔﻦ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﺷﺮﮐﺖ ﻫﺎ ‪ ،‬ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﻫﺎﯼ ﺧﺎﺻﯽ ﺭﺍ ﺑﻤﻨﻈﻮﺭ ﺗﻤﺎﺱ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﻣﻌﻤﻮﻟﯽ ﺗﻠﻔﻦ ﺑﺎ ﮐﺎﺭﺑﺮﺍﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﻧﺼﺐ ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬

‫ﺧﺎﺹ ﺑﻤﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﺑﺮ ﺭﻭﯼ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ‪ ،‬ﺍﻟﺰﺍﻣﯽ‬ ‫ﺍﺳﺖ‪.‬‬

‫•‬

‫ﺗﻠﻔﻦ ﺑﻪ ﺗﻠﻔﻦ ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ Gateways‬ﻣﯽ ﺗﻮﺍﻥ ﺑﺎ ﻫﺮ ﺗﻠﻔﻦ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺩﺭ ﺳﻄﺢ‬ ‫ﺩﻧﻴﺎ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﮐﺮﺩ‪ .‬ﺑﺮﺍﯼ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﮐﻪ ﺗﻮﺳﻂ ﺑﺮﺧﯽ ﺍﺯ ﺷﺮﮐﺖ‬

‫ﻫﺎ ﺍﺭﺍﺋﻪ ﻣﯽ ﮔﺮﺩﺩ‪ ،‬ﻣﯽ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﻳﮑﯽ ﺍﺯ ‪ Gateway‬ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺁﻧﺎﻥ‬

‫ﺗﻤﺎﺱ ﺑﺮﻗﺮﺍﺭ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﻣﺸﺨﺺ ﻭ ﻧﻬﺎﻳﺘﺎ" ﺗﻮﺳﻂ‬ ‫‪79‬‬

‫ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ IP‬ﻓﺮﺍﻫﻢ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺍﺑﺘﺪﺍ ﺍﺯ ﻳﮏ ﺷﻤﺎﺭﻩ ﺧﺎﺹ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﮔﺮﺩﺩ‪ ).‬ﺷﻤﺎﺭﻩ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Gateway‬ﺷﺮﮐﺖ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﻓﻮﻕ (‪.‬‬ ‫ﺍﮐﺜﺮ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺑﺎ ﻧﺼﺐ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ‪ VoIP‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ IP‬ﺗﻠﻔﻨﯽ ﺭﺍ‬

‫ﺑﺮﺍﯼ ﮐﺎﺭﺑﺮﺍﻥ ﺧﻮﺩ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﯼ ﻓﻮﻕ ﺑﺎ ﺳﺮﻋﺖ ﺩﺭ ﺣﺎﻝ ﺭﺷﺪ ﻭ ﮔﺴﺘﺮﺵ‬ ‫ﻫﻤﮕﺎﻧﯽ ﺍﺳﺖ‪ .‬ﮐﻴﻔﻴﺖ ﺑﺎﻻ ﻭ ﻫﺰﻳﻨﻪ ﭘﺎﻳﻴﻦ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﺩﻻﻳﻞ ﻓﺮﺍﮔﻴﺮ ﺷﺪﻥ ﺗﮑﻨﻮﻟﻮﮊﯼ ﻓﻮﻕ‬ ‫ﺍﺳﺖ‪.‬‬

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‫ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬ ‫ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺳﺎﻟﻴﺎﻥ ﺍﺧﻴﺮ ﺑﺎ ﺍﺳﺘﻘﺒﺎﻝ ﮔﺴﺘﺮﺩﻩ ﺟﻮﺍﻣﻊ ﺑﺸﺮﯼ ﺭﻭﺑﺮﻭ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﺍﻣﺮﻭﺯﻩ ﮐﻤﺘﺮ ﺷﺨﺼﯽ ﺭﺍ ﻣﯽ ﺗﻮﺍﻥ ﻳﺎﻓﺖ ﮐﻪ ﻭﺍﮊﻩ ﻓﻮﻕ ﺑﺮﺍﯼ ﺍﻭ ﺑﻴﮕﺎﻧﻪ ﺑﺎﺷﺪ‪ .‬ﻧﺸﺮﻳﺎﺕ‪،‬‬ ‫ﺭﺍﺩﻳﻮ ﻭ ﺗﻠﻮﻳﺰﻳﻮﻥ ﺑﻪ ﺻﻮﺭﺕ ﺭﻭﺯﺍﻧﻪ ﻣﻮﺿﻮﻋﺎﺗﯽ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﻣﻨﺘﺸﺮ‬

‫ﻭ ﺍﻓﺮﺍﺩ ﻭ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﺍﺯ ﺯﻭﺍﻳﺎﯼ ﻣﺘﻔﺎﻭﺕ ﺑﻪ ﺑﺮﺭﺳﯽ ﻣﻘﻮﻟﻪ ﻓﻮﻕ ﻣﯽ ﭘﺮﺩﺍﺯﻧﺪ‪ .‬ﺷﺮﮐﺖ ﻫﺎ ﻭ‬

‫ﻣﻮﺳﺴﺎﺕ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﻫﻤﮕﺎﻡ ﺑﺎ ﺳﻴﺮ ﺗﺤﻮﻻﺕ ﺟﻬﺎﺗﯽ ﺩﺭ ﺯﻣﻴﻨﻪ ﺗﺠﺎﺭﺕ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺗﻼﺵ ﺑﺮﺍﯼ ﺗﻐﻴﻴﺮ ﺳﺎﺧﺘﺎﺭ ﻣﻨﻄﻘﯽ ﻭ ﻓﻴﺰﻳﮑﯽ ﺳﺎﺯﻣﺎﻥ ﺧﻮﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ‬ ‫ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺗﺠﺎﺭﺕ‬

‫ﻗﺒﻞ ﺍﺯ ﺑﺮﺭﺳﯽ " ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ "‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﻳﮏ ﺗﺼﻮﻳﺮ ﺫﻫﻨﯽ ﻣﻨﺎﺳﺐ ﺍﺯ‬

‫ﺗﺠﺎﺭﺕ ﺳﻨﺘﯽ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﺎﺋﻴﻢ ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺷﻨﺎﺧﺖ " ﺗﺠﺎﺭﺕ "‪ ،‬ﺑﺎ " ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ "‬

‫ﻧﻴﺰ ﺁﺷﻨﺎ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬ ‫ﺑﺮﺍﯼ ﻭﺍﮊﻩ "ﺗﺠﺎﺭﺕ" ﺩﺭ ﺍﮐﺜﺮ ﻭﺍﮊﻩ ﻧﺎﻣﻪ ﻫﺎ ﺗﻌﺎﺭﻳﻒ ﺯﻳﺮ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﻣﺒﺎﺩﻻﺕ ﺍﺟﺘﻤﺎﻋﯽ‪ :‬ﺗﺒﺎﺩﻝ ﺍﻳﺪﻩ ﻫﺎ ‪ ،‬ﻋﻘﺎﻳﺪ ﻭ ﺗﻤﺎﻳﻼﺕ ) ﺧﻮﺍﺳﺘﻪ ﻫﺎ (‬

‫•‬

‫ﻣﺒﺎﺩﻟﻪ ﻳﺎ ﺧﺮﻳﺪ ﻭ ﻓﺮﻭﺵ ﮐﺎﻻ ﺩﺭ ﻣﻘﻴﺎﺱ ﺑﺎﻻ ﮐﻪ ﺑﻪ ﻫﻤﺮﺍﻩ ﺣﻤﻞ ﮐﺎﻻ ﺍﺯ ﻧﻘﻄﻪ ﺍﯼ ﺑﻪ‬ ‫ﻧﻘﻄﻪ ﺍﯼ ﺩﻳﮕﺮ ﻣﯽ ﺑﺎﺷﺪ ‪.‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ‪ ،‬ﺗﻌﺮﻳﻒ ﺩﻭﻡ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﺮﺍﯼ "ﺗﺠﺎﺭﺕ " ﺭﺍ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺤﻮﺭ ﺑﺤﺚ ﺍﻧﺘﺨﺎﺏ ﻭ ﺑﺮ‬

‫ﺭﻭﯼ ﺁﻥ ﻣﺘﻤﺮﮐﺰ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬

‫ﺗﺠﺎﺭﺕ ﺩﺭ ﺳﺎﺩﻩ ﺗﺮﻳﻦ ﻧﮕﺎﻩ‪ ،‬ﻣﺒﺎﺩﻟﻪ ﮐﺎﻻ ﻭ ﺧﺪﻣﺎﺕ ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﺴﺐ ﺩﺭﺁﻣﺪ ) ﭘﻮﻝ ( ﺍﺳﺖ‪.‬‬ ‫ﺯﻧﺪﮔﯽ ﺍﻧﺴﺎﻥ ﻣﻤﻠﻮ ﺍﺯ ﻓﺮﺁﻳﻨﺪﻫﺎﯼ ﺗﺠﺎﺭﯼ ﺑﻮﺩﻩ ﻭ ﺗﺠﺎﺭﺕ ﺑﺎ ﻣﻴﻠﻴﻮﻧﻬﺎ ﺷﮑﻞ ﻣﺘﻔﺎﻭﺕ ﺩﺭ‬

‫ﺯﻧﺪﮔﯽ ﺑﺸﺮﻳﺖ ﻧﻤﻮﺩ ﭘﻴﺪﺍ ﮐﺮﺩﻩ ﺍﺳﺖ ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﻻﯼ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻳﮏ ﻓﺮﻭﺷﮕﺎﻩ‬ ‫ﺗﺎﻣﻴﻦ ﻭ ﺧﺮﻳﺪﺍﺭﯼ ﻣﯽ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺩﺭ ﺗﺠﺎﺭﺕ ﺷﺮﻳﮏ ﻭ ﺩﺭ ﻓﺮﺁﻳﻨﺪﻫﺎﯼ ﺁﻥ ﺩﺭﮔﻴﺮ ﺷﺪﻩ ﺍﻳﺪ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻴﮑﻪ ﺩﺭ ﺷﺮﮐﺘﯽ ﻣﺸﻐﻮﻝ ﺑﮑﺎﺭ ﻫﺴﺘﻴﺪ ﮐﻪ ﮐﺎﻻﺋﯽ ﺭﺍ ﺗﻮﻟﻴﺪ ﻣﯽ ﻧﻤﺎﻳﺪ ‪ ،‬ﺩﺭﮔﻴﺮ ﻳﮑﯽ ﺩﻳﮕﺮ‬

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‫ﺍﺯ ﺯﻧﺠﻴﺮﻩ ﻫﺎﯼ ﺗﺠﺎﺭﺕ ﺷﺪﻩ ﺍﻳﺪ‪ .‬ﺗﻤﺎﻡ ﺟﻠﻮﻩ ﻫﺎﯼ ﺗﺠﺎﺭﺕ ﺑﺎ ﻫﺮ ﺭﻭﻳﮑﺮﺩ ﻭ ﺳﻴﺎﺳﺘﯽ ﺩﺍﺭﺍﯼ‬ ‫ﺧﺼﺎﻳﺺ ﺯﻳﺮ ﻣﯽ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫ﺧﺮﻳﺪﺍﺭﺍﻥ ‪ .‬ﺍﻓﺮﺍﺩﻳﮑﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﻝ ﺧﻮﺩ ﻗﺼﺪ ﺧﺮﻳﺪ ﻳﮏ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺭﺍ‬

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‫ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ‪ .‬ﺍﻓﺮﺍﺩﻳﮑﻪ ﮐﺎﻻ ﻭ ﺧﺪﻣﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺧﺮﻳﺪﺍﺭﺍﻥ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﺩﻫﻨﺪ‪.‬‬

‫ﺩﺍﺭﻧﺪ‪.‬‬

‫ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﺑﻪ ﺩﻭ ﮔﺮﻭﻉ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﻣﯽ ﮔﺮﺩﻧﺪ‪ :‬ﺧﺮﺩﻩ ﻓﺮﻭﺷﺎﻥ‪ ،‬ﮐﻪ ﮐﺎﻻ ﻭ ﻳﺎ‬ ‫ﺧﺪﻣﺎﺗﯽ ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ" ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻭ ﻋﻤﺪﻩ ﻓﺮﻭﺷﺎﻥ ﻭ ﻋﻮﺍﻣﻞ‬ ‫ﻓﺮﻭﺵ‪ ،‬ﮐﻪ ﮐﺎﻻ ﻭ ﺧﺪﻣﺎﺕ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺧﺮﺩﻩ ﻓﺮﻭﺷﺎﻥ ﻭ ﺳﺎﻳﺮ ﻣﻮﺳﺴﺎﺕ‬ ‫ﺗﺠﺎﺭﯼ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ‪ .‬ﺍﻓﺮﺍﺩﻳﮑﻪ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺗﯽ ﺭﺍ ﺍﻳﺠﺎﺩ ﺗﺎ ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﺁﻧﻬﺎ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬ ‫ﺧﺮﻳﺪﺍﺭﺍﻥ ﻗﺮﺍﺭ ﺩﻫﻨﺪ‪ .‬ﻳﮏ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ ﮐﺎﺭ ﺧﻮﺩ ﻫﻤﻮﺍﺭﻩ ﻳﮏ‬

‫ﻓﺮﻭﺷﻨﺪﻩ ﻧﻴﺰ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﮐﺎﻻﯼ ﺗﻮﻟﻴﺪﯼ ﺧﻮﺩ ﺭﺍ ﺑﻪ ﻋﻤﺪﻩ ﻓﺮﻭﺷﺎﻥ ‪،‬‬ ‫ﺧﺮﺩﻩ ﻓﺮﻭﺷﺎﻥ ﻭ ﻳﺎ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﻣﺼﺮﻑ ﮐﻨﻨﺪﻩ ﮔﺎﻥ ﻣﯽ ﻓﺮﻭﺷﻨﺪ‪.‬‬ ‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻣﺸﺎﻫﺪﻩ ﻣﯽ ﮔﺮﺩﺩ ‪" ،‬ﺗﺠﺎﺭﺕ " ﺍﺯ ﺯﺍﻭﻳﻪ ﻓﻮﻕ ﺩﺍﺭﺍﯼ ﻣﻔﺎﻫﻴﻢ ﺳﺎﺩﻩ ﺍﯼ ﺍﺳﺖ‪.‬‬

‫ﺗﺠﺎﺭﺕ ﺍﺯ ﺧﺮﻳﺪ ﻳﮏ ﻣﺤﺼﻮﻝ ﺳﺎﺩﻩ ﻧﻈﻴﺮ " ﺑﺴﺘﻨﯽ " ﺗﺎ ﻣﻮﺍﺭﺩ ﭘﻴﭽﻴﺪﻩ ﺍﯼ ﻧﻈﻴﺮ ﺍﺟﺎﺭﻩ‬ ‫ﻣﺎﻫﻮﺍﺭﻩ ﺭﺍ ﺷﺎﻣﻞ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺗﻤﺎﻡ ﺟﻠﻮﻩ ﻫﺎﯼ ﺗﺠﺎﺭﺕ ﺍﺯ ﺳﺎﺩﻩ ﺗﺮﻳﻦ ﺳﻄﺢ ﺗﺎ ﭘﻴﭽﻴﺪﻩ ﺗﺮﻳﻦ‬ ‫ﺣﺎﻟﺖ ﺁﻥ ‪ ،‬ﺑﺮ ﻣﻘﻮﻻﺗﯽ ﻫﻤﭽﻮﻥ ‪ :‬ﺧﺮﻳﺪﺍﺭﺍﻥ ‪ ،‬ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﻭ ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﻣﺘﻤﺮﮐﺰ ﺧﻮﺍﻫﺪ‬

‫ﺑﻮﺩ‪.‬‬

‫ﻋﻨﺎﺻﺮ ﺗﺠﺎﺭﺕ‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﻗﺼﺪ ﻣﻌﺮﻓﯽ ﻋﻨﺎﺻﺮ ﺫﻳﺮﺑﻂ ﺩﺭ ﺗﺠﺎﺭﺕ ﻭ ﻓﻌﺎﻟﻴﺖ ﻫﺎﯼ ﺗﺠﺎﺭﯼ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪،‬‬

‫ﻣﻮﺿﻮﻋﺎﺕ ﻭ ﻣﻮﺍﺭﺩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺪﻟﻴﻞ ﺩﺭﮔﻴﺮ ﺷﺪﻥ ﺑﺎ ﺟﺰﺋﻴﺎﺕ ﭘﻴﭽﻴﺪﻩ ﺗﺮ ﺑﻨﻈﺮ ﺧﻮﺍﻫﻨﺪ ﺁﻣﺪ‪.‬‬ ‫ﻋﻨﺎﺻﺮ ﺫﻳﻞ ﺗﻤﺎﻡ ﺍﻟﻤﺎﻥ ﻫﺎﯼ ﺫﻳﺮﺑﻂ ﺩﺭ ﻳﮏ ﻓﻌﺎﻟﻴﺖ ﺗﺠﺎﺭﯼ ﻣﻌﻤﻮﻟﯽ ﺭﺍ ﺗﺸﺮﻳﺢ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ‪ ،‬ﻓﻌﺎﻟﻴﺖ ﺷﺎﻣﻞ ﻓﺮﻭﺵ ﺑﺮﺧﯽ ﻣﺤﺼﻮﻻﺕ ﺗﻮﺳﻂ ﻳﮏ ﺧﺮﺩﻩ ﻓﺮﻭﺵ ﺑﻪ‬

‫ﻣﺼﺮﻑ ﮐﻨﻨﺪﻩ ﺍﺳﺖ ‪:‬‬ ‫‪82‬‬

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‫ﺩﺭ ﺻﻮﺭﺕ ﺗﻤﺎﻳﻞ ﻓﺮﻭﺵ ﻣﺤﺼﻮﻝ ﻭ ﻳﺎ ﻣﺤﺼﻮﻻﺗﯽ ﺑﻪ ﻳﮏ ﻣﺼﺮﻑ ﮐﻨﻨﺪﻩ‪ ،‬ﻣﺴﺌﻠﻪ‬

‫ﺍﺳﺎﺳﯽ ﺩﺍﺷﺘﻦ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺗﯽ ﺧﺎﺹ ﺑﺮﺍﯼ ﻋﺮﺿﻪ ﺍﺳﺖ‪ .‬ﮐﺎﻻ ﻣﯽ ﺗﻮﺍﻧﺪ ﻫﺮ ﭼﻴﺰﯼ‬ ‫ﺭﺍ ﺷﺎﻣﻞ ﮔﺮﺩﺩ‪ .‬ﻓﺮﻭﺷﻨﺪﻩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﮐﺎﻻﯼ ﺧﻮﺩ ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ" ﺍﺯ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﻭ ﻳﺎ‬ ‫ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﻋﺎﻣﻞ ﻓﺮﻭﺵ ﺗﻬﻴﻪ ﮐﺮﺩﻩ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺑﺮﺧﯽ ﺣﺎﻻﺕ ﻣﻤﮑﻦ ﺍﺳﺖ ﻓﺮﻭﺷﻨﺪﻩ‬

‫‪ ،‬ﺧﻮﺩ ﮐﺎﻻﺋﯽ ﺭﺍ ﺗﻮﻟﻴﺪ ﻭ ﺑﻘﺮﻭﺵ ﻣﯽ ﺭﺳﺎﻧﺪ‪.‬‬ ‫•‬

‫ﻓﺮﻭﺷﻨﺪﻩ ﺑﺮﺍﯼ ﻓﺮﻭﺵ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﻣﯽ ﺑﺎﻳﺴﺖ " ﻣﮑﺎﻧﯽ ﻣﻨﺎﺳﺐ " ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬ ‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﻣﮑﺎﻥ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﯽ ﺗﻮﺍﻧﺪ ﺩﺭ ﺑﺮﺧﯽ ﺣﺎﻻﺕ ﺑﺴﻴﺎﺭ ﻣﻮﻗﺘﯽ ﺑﺎﺷﺪ‪ .‬ﻣﺜﻼ"‬

‫ﻳﮏ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﺧﻮﺩ ﺑﻤﻨﺰﻟﻪ ﻳﮏ ﻣﮑﺎﻥ ﺍﺳﺖ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﯼ ﻣﺘﻘﺎﺿﯽ ﮐﺎﻻ ﻭ ﻳﺎ‬ ‫ﺧﺪﻣﺎﺕ ﺑﺎ ﺗﻤﺎﺱ ﺗﻠﻔﻨﯽ ﺑﺎ ﻓﺮﻭﺷﻨﺪﻩ ﻗﺎﺩﺭ ﺑﻪ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﻭ ﺩﺭﻳﺎﻓﺖ ﮐﺎﻻﯼ ﻣﻮﺭﺩ‬ ‫ﻧﻈﺮ ﺧﻮﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺮﺍﯼ ﺍﮐﺜﺮ ﮐﺎﻻﻫﺎﯼ ﻓﻴﺰﻳﮑﯽ ﻣﯽ ﺑﺎﻳﺴﺖ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ‪ ،‬ﻳﮏ‬

‫ﻣﻐﺎﺯﻩ ﻭ ﻳﺎ ﻓﺮﻭﺷﮕﺎﻩ ﺑﺎﺷﺪ‪.‬‬ ‫•‬

‫ﺑﺮﺍﯼ ﻓﺮﻭﺵ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ‪ ،‬ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﺭﺍﻫﮑﺎﺭﻫﺎﺋﯽ ﺑﺮﺍﯼ ﺟﺬﺏ‬ ‫ﺍﻓﺮﺍﺩ ﺑﻪ ﻣﮑﺎﻥ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ " ﻣﺎﺭﮐﺘﻴﻨﮓ " ﻧﺎﻣﻴﺪﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﺩﺭ‬

‫ﺻﻮﺭﺗﻴﮑﻪ ﺍﻓﺮﺍﺩ ﺍﺯ ﻣﺤﻞ ﻭ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﻳﮏ ﮐﺎﻻ ﻭ ﺧﺪﻣﺎﺕ ﺁﮔﺎﻫﯽ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﻓﺮﻭﺵ ﻫﻴﭽﮕﻮﻧﻪ ﮐﺎﻻﺋﯽ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺍﻧﺘﺨﺎﺏ ﻣﺤﻞ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﺩﺭ‬ ‫ﻳﮏ ﻣﺮﮐﺰ ﺗﺠﺎﺭﯼ ﺷﻠﻮﻍ ‪ ،‬ﻳﮑﯽ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﺍﻓﺰﺍﻳﺶ ﺗﺮﺩﺩ ﺑﻪ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﺍﺳﺖ‪.‬‬

‫ﺍﺭﺳﺎﻝ ﭘﺴﺘﯽ ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎ ﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﻣﺤﺼﻮﻻﺕ‪ ،‬ﻳﮑﯽ ﺩﻳﮕﺮ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ‬

‫ﻣﻌﺮﻓﯽ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﻳﮏ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺍﺳﺖ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺷﻴﻮﻩ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ‬ ‫ﺗﺒﻠﻴﻐﺎﺗﯽ‪ ،‬ﺭﺍﻫﮑﺎﺭﯼ ﺩﻳﮕﺮ ﺩﺭ ﻣﻌﺮﻓﯽ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﻓﺮﻭﺷﻨﺪﻩ ﻧﻴﺎﺯﻣﻨﺪ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺩﺭﻳﺎﻓﺖ ﺳﻔﺎﺭﺷﺎﺕ ﺍﺳﺖ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻠﻔﻦ ﻭ ﻧﺎﻣﻪ‪،‬‬ ‫ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﺩﺭﻳﺎﻓﺖ ﺳﻔﺎﺭﺵ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻣﯽ ﺑﺎﺷﺪ‪ .‬ﺣﻀﻮﺭ ﻓﻴﺰﻳﮑﯽ ﺩﺭ‬

‫ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ ﻳﮏ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺍﺯ ﺩﻳﮕﺮ ﺭﻭﺵ ﻫﺎﯼ ﺳﻨﺘﯽ ﺑﺮﺍﯼ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﮐﺎﻻ‬ ‫ﺍﺳﺖ ‪ .‬ﭘﺲ ﺍﺯ ﺛﺒﺖ ﺳﻔﺎﺭﺵ‪ ،‬ﻓﺮﺁﻳﻨﺪﻫﺎﯼ ﻻﺯﻡ ﺗﻮﺳﻂ ﭘﺮﺳﻨﻞ ﺷﺎﻏﻞ ﺩﺭ ﺷﺮﮐﺖ ﻭ ﻳﺎ‬

‫ﻣﻮﺳﺴﻪ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪.‬‬ ‫‪83‬‬

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‫ﻓﺮﻭﺷﻨﺪﻩ ﻧﻴﺎﺯﻣﻨﺪ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺩﺭﻳﺎﻓﺖ ﭘﻮﻝ ﺍﺳﺖ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭼﮏ‪ ،‬ﮐﺎﺭﺕ ﺍﻋﺘﺒﺎﺭﯼ ﻭ‬ ‫ﻳﺎ ﭘﻮﻝ ﻧﻘﺪ ﺭﻭﺵ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺑﺮﺧﯽ ﺍﺯ ﻓﻌﺎﻟﻴﺖ ﻫﺎﯼ‬ ‫ﺗﺠﺎﺭﯼ ﺍﺯ ﻓﺮﻭﺷﻨﺪﻩ ﺗﺎ ﺯﻣﺎﻥ ﺗﻮﺯﻳﻊ ﮐﺎﻻ ﭘﻮﻟﯽ ﺩﺭﻳﺎﻓﺖ ﻧﻤﯽ ﮔﺮﺩﺩ‪.‬‬

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‫ﻓﺮﻭﺷﻨﺪﻩ ﻧﻴﺎﺯﻣﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﻋﺮﺿﻪ ﻭ ﺗﻮﺯﻳﻊ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﻣﯽ ﺑﺎﺷﺪ‪.‬‬ ‫ﺩﺭ ﺑﺮﺧﯽ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎ ﺑﻤﺤﺾ ﺍﻧﺘﺨﺎﺏ ﮐﺎﻻ ﺗﻮﺳﻂ ﻣﺸﺘﺮﯼ ﻭ ﭘﺮﺩﺍﺧﺖ ﻭﺟﻪ ﺁﻥ‪،‬‬

‫ﻋﻤﻠﻴﺎﺕ ﺗﻮﺯﻳﻊ ﮐﺎﻻ ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﺛﺒﺖ‬ ‫ﺳﻔﺎﺭﺵ ﻣﺒﺘﻨﯽ ﺑﺮ ﻧﺎﻣﻪ‪ ،‬ﮐﺎﻻﯼ ﺧﺮﻳﺪﺍﺭﯼ ﺷﺪﻩ ﭘﺲ ﺍﺯ ﺑﺴﺘﻪ ﺑﻨﺪﯼ ﺑﻪ ﻣﻘﺼﺪ ﻣﺸﺘﺮﯼ‬

‫ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺣﺠﻢ ﮐﺎﻻ ﺯﻳﺎﺩ ﻧﺒﺎﺷﺪ ﺍﺯ ﻣﺒﺎﺩﻻﺕ ﭘﺴﺘﯽ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺍﺭﺳﺎﻝ ﮐﺎﻻ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺣﺠﻢ ﮐﺎﻻ ﺯﻳﺎﺩ ﺑﺎﺷﺪ ﺍﺯ ﮐﺎﻣﻴﻮﻥ‪ ،‬ﻗﻄﺎﺭ ﻭ ﻳﺎ‬ ‫ﮐﺸﺘﯽ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﻭ ﺗﻮﺯﻳﻊ ﮐﺎﻻ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

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‫ﺩﺭ ﺑﺮﺧﯽ ﻣﻮﺍﺭﺩ ‪ ،‬ﺧﺮﻳﺪﺍﺭﺍﻥ ﻳﮏ ﮐﺎﻻ ﺗﻤﺎﻳﻞ ﻭ ﻋﻼﻗﻪ ﺍﯼ ﻧﺴﺒﺖ ﺑﻪ ﺁﻥ ﭼﻴﺰﯼ ﮐﻪ‬ ‫ﺧﺮﻳﺪﺍﺭﯼ ﻧﻤﻮﺩﻩ ﺍﻧﺪ ﻧﺪﺍﺷﺘﻪ ﻭ ﻗﺼﺪ ﺑﺮﮔﺸﺖ ﺁﻥ ﺭﺍ ﺩﺍﺭﻧﺪ‪ .‬ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﮐﺎﻻ ﻭ ﻳﺎ‬ ‫ﺧﺪﻣﺎﺕ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﺭﻭﺵ ﻫﺎﺋﯽ ﺑﺮﺍﯼ ﻗﺒﻮﻝ ﻣﻮﺍﺭﺩ "ﺑﺮﮔﺸﺖ ﺍﺯ ﻓﺮﻭﺵ " ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﺑﺮﺧﯽ ﻣﻮﺍﺭﺩ ﻣﻤﮑﻦ ﺍﺳﺖ ﮐﺎﻻﺋﯽ ﺩﺭ ﺯﻣﺎﻥ ﺗﻮﺯﻳﻊ ﺁﺳﻴﺐ ﺩﻳﺪﻩ ﺑﺎﺷﺪ‪ .‬ﻓﺮﻭﺷﻨﺪﮔﺎﻥ‬ ‫ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﺑﺮﺍﯼ ﺗﻀﻤﻴﻦ ﮔﺎﺭﺍﻧﺘﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺑﺮﺧﯽ ﺍﺯ ﮐﺎﻻﻫﺎﯼ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﻪ ﻣﺸﺘﺮﻳﺎﻥ ﺩﺍﺭﺍﯼ ﭘﻴﭽﻴﺪﮔﯽ ﻫﺎﯼ ﺧﺎﺹ ﺧﻮﺩ ﺑﻮﺩﻩ ﻭ‬ ‫ﻧﻴﺎﺯﻣﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﺪﻣﺎﺕ ﭘﺲ ﺍﺯ ﻓﺮﻭﺵ ﻭ ﻳﺎ ﺣﻤﺎﻳﺖ ﻓﻨﯽ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ‬ ‫ﻣﻮﺍﺭﺩﯼ ﻭﺟﻮﺩ ﺑﺨﺶ ﻫﺎﺋﯽ ﺩﺭ ﺷﺮﮐﺖ ﻭ ﻳﺎ ﻣﻮﺳﺴﻪ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ‬ ‫ﺍﻟﺰﺍﻣﯽ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻳﮑﯽ ﺍﺯ ﻧﻤﻮﻧﻪ ﮐﺎﻻﻫﺎﺋﯽ ﺍﺳﺖ ﮐﻪ ﻧﻴﺎﺯﻣﻨﺪ ﺧﺪﻣﺎﺕ ﭘﺲ‬

‫ﺍﺯ ﻓﺮﻭﺵ ﻭ ﺣﻤﺎﻳﺖ ﻓﻨﯽ ﺍﺯ ﺩﻳﺪﮔﺎﻩ ﻣﺸﺘﺮﻳﺎﻥ ) ﺧﺮﻳﺪﺍﺭﺍﻥ ( ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺗﻤﺎﻡ ﻋﻨﺎﺻﺮ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺭﺍ ﻣﯽ ﺗﻮﺍﻥ ﺩﺭ ﻳﮏ ﺷﺮﮐﺖ ﺗﺠﺎﺭﯼ ﺳﻨﺘﯽ ﻣﺸﺎﻫﺪﻩ ﮐﺮﺩ‪ .‬ﻓﻌﺎﻟﻴﺖ‬ ‫ﻫﺎﯼ ﺗﺠﺎﺭﯼ ﺷﺮﮐﺖ ﻫﺎﯼ ﻓﻮﻕ ﻣﯽ ﺗﻮﺍﻧﺪ ﺷﺎﻣﻞ ﻣﻘﻮﻟﻪ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺗﯽ ﺑﺎﺷﺪ‪.‬‬

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‫ﺩﺭ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺗﻤﺎﻡ ﻋﻨﺎﺻﺮ ﺍﺷﺎﺭﻩ ﺷﺪﻩ‪ ،‬ﺣﻀﻮﺭﯼ ﻣﺸﻬﻮﺩ ﺑﺎ ﺗﻐﻴﻴﺮﺍﺕ ﺧﺎﺻﯽ ﺩﺍﺭﻧﺪ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺪﻳﺮﻳﺖ ﻭ ﺍﺟﺮﺍﯼ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻪ ﻋﻨﺎﺻﺮ ﺯﻳﺮ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪:‬‬ ‫•‬

‫ﻳﮏ ﻣﺤﺼﻮﻝ‬

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‫ﻣﺤﻠﯽ ﺑﺮﺍﯼ ﻓﺮﻭﺵ ﮐﺎﻻ‪ .‬ﺩﺭ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﺑﻤﻨﺰﻟﻪ ﻣﮑﺎﻥ ﺍﺭﺍﺋﻪ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻭ ﻳﺎ ﺭﻭﺵ ﻫﺎﺋﯽ ﺑﺮﺍﯼ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺎﻳﺖ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺛﺒﺖ ﺳﻔﺎﺭﺵ‪ ).‬ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ﻓﺮﻡ ﻫﺎ ﺋﯽ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺩﺭﻳﺎﻓﺖ ﭘﻮﻝ‪ ) .‬ﮐﺎﺭﺕ ﺍﻋﺘﺒﺎﺭﯼ ﺍﺯ ﻧﻤﻮﻧﻪ ﻫﺎﯼ ﻣﺘﺪﺍﻭﻝ ﺍﺳﺖ (‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺗﻮﺯﻳﻊ ﮐﺎﻻ‬

‫ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﻣﯽ ﺷﻮﺩ(‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﻣﻮﺍﺭﺩ ﺑﺮﮔﺸﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺗﻮﺳﻂ ﺧﺮﻳﺪﺍﺭﺍﻥ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﻣﻮﺍﺭﺩ ﻣﺮﺑﻮﻁ ﺑﻪ ﮔﺎﺭﺍﻧﺘﯽ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺷﯽ ﺑﺮﺍﯼ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﭘﺲ ﺍﺯ ﻓﺮﻭﺵ ) ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﺍﺭﺍﺋﻪ‬ ‫ﭘﺎﻳﮕﺎﻩ ﻫﺎﯼ ﺍﻃﻼﻉ ﺭﺳﺎﻧﯽ ﻭ‪(...‬‬

‫ﭼﺮﺍ ﺗﺒﻠﻴﻐﺎﺕ ﺯﻳﺎﺩ ؟‬ ‫ﭘﻴﺮﺍﻣﻮﻥ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺗﺒﻠﻴﻐﺎﺕ ﺯﻳﺎﺩ ﻭ ﮔﺎﻫﺎ" ﺑﯽ ﺭﻭﻳﻪ ﺍﯼ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﻋﻠﺖ‬ ‫ﺗﺒﻠﻴﻐﺎﺕ ﺯﻳﺎﺩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﻣﯽ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻨﺎﺩ ﺑﻪ ﺑﺮﺧﯽ ﺍﺯ ﺁﻣﺎﺭﻫﺎ ﻭ‬ ‫ﺍﺭﻗﺎﻡ ﻣﻮﺟﻮﺩ ﻣﺘﻮﺟﻪ ﺷﺪ‪:‬‬ ‫•‬

‫ﺗﺎ ﺳﺎﻝ ‪ ٢٠٠١‬ﻣﻴﻼﺩﯼ ﺑﺎﻟﻎ ﺑﺮ ‪ ١٧‬ﻣﻴﻠﻴﺎﺭﺩ ﺩﻻﺭ ﺩﺭ ﺳﻄﺢ ﺧﺮﺩﻩ ﻓﺮﻭﺷﯽ ﻣﺒﺎﺩﻻﺕ‬ ‫ﺗﺠﺎﺭﯼ ﺻﻮﺭﺕ ﮔﺮﻓﺘﻪ ﺍﺳﺖ‪.‬‬

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‫ﺗﻌﺪﺍﺩ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺍﺯ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺯ ﺭﻗﻢ ‪ ١,٣‬ﻣﻴﻠﻴﻮﻥ ﻧﻔﺮ ﺩﺭ ﺳﺎﻝ ‪١٩٩٦‬‬ ‫ﺑﻪ ‪ ٨‬ﻣﻴﻠﻴﻮﻥ ﻧﻔﺮ ﺩﺭ ﺳﺎﻝ ‪ ٢٠٠١‬ﺭﺳﻴﺪﻩ ﺍﺳﺖ‪.‬‬

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‫‪ ٧٠‬ﺩﺭﺻﺪ ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﻣﻨﺰﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻭ ﺍﻳﻦ‬ ‫ﮔﺮﻭﻩ ‪ ٦٠‬ﺩﺭﺻﺪ ﺧﺮﻳﺪ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩﻩ ﺍﻧﺪ‪.‬‬

‫ﺑﺮ ﺍﺳﺎﺱ ﺁﻣﺎﺭﻫﺎﯼ ﻣﻮﺟﻮﺩ‪ ،‬ﮔﺮﻭﻩ ﮐﺎﻻﻫﺎﯼ ﺯﻳﺮ ﺩﺍﺭﺍﯼ ﺑﻴﺸﺘﺮﻳﻦ ﻣﻴﺰﺍﻥ ﻓﺮﻭﺵ ﺗﺠﺎﺭﺕ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﺑﺨﻮﺩ ﺍﺧﺘﺼﺎﺹ ﺩﺍﺩﻩ ﺍﻧﺪ‪:‬‬ ‫•‬

‫ﻣﺤﺼﻮﻻﺕ ﮐﺎﻣﭙﻴﻮﺗﺮﯼ ) ﻧﺮﻡ ﺍﻓﺰﺍﺭ‪ ،‬ﺳﺨﺖ ﺍﻓﺰﺍﺭ (‬

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‫ﮐﺘﺎﺏ‬

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‫ﺧﺪﻣﺎﺕ ﻣﺎﻟﯽ‬

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‫ﺳﺮﮔﺮﻣﯽ ﻫﺎ‬

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‫ﻣﻮﺯﻳﮏ‬

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‫ﺍﻟﮑﺘﺮﻭﻧﻴﮏ ﻫﺎﯼ ﺧﺎﻧﮕﯽ‬

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‫ﭘﻮﺷﺎﮎ‬

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‫ﻫﺪﺍﻳﺎ ﻭ ﮔﻞ‬

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‫ﺧﺪﻣﺎﺕ ﻣﺴﺎﻓﺮﺗﯽ‬

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‫ﺍﺳﺒﺎﺏ ﺑﺎﺯﯼ‬

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‫ﺑﻠﻴﻂ ﻓﺮﻭﺷﯽ‬

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‫ﺍﻃﻼﻋﺎﺕ‬

‫ﺑﺮﺭﺳﯽ ﺷﺮﮐﺖ ‪Dell‬‬

‫ﺍﻣﺮﻭﺯﻩ ﺷﺮﮐﺖ ﻫﺎﯼ ﮐﻮﭼﮏ ﻭ ﺑﺰﺭﮒ ﺑﺎ ﺣﺮﮐﺎﺕ ﺳﺮﺍﺳﻴﻤﻪ ﻭ ﺷﺘﺎﺑﺎﻥ ﺑﺴﺮﻋﺖ ﺑﺴﻤﺖ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﺟﺪﻳﺪ ) ﺍﻳﻨﺘﺮﻧﺖ ( ﺑﺮﺍﯼ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻋﻠﺖ ﺍﻳﻦ‬ ‫ﻫﻤﻪ ﺗﻌﺠﻴﻞ ﻭ ﺑﻨﻮﻋﯽ ﺷﻴﺪﺍﺋﯽ ﺩﺭ ﭼﻴﺴﺖ؟ ﺷﺮﮐﺖ ‪ Dell‬ﻳﮑﯽ ﺍﺯ ﻣﻮﻓﻘﺘﺮﻳﻦ ﺷﺮﮐﺖ ﻫﺎﯼ‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺯﻣﻴﻨﻪ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺖ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺷﺎﻳﺴﺘﻪ ﺍﺳﺖ ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﺑﻪ‬ ‫ﺑﺮﺭﺳﯽ ﻭﺿﻌﻴﺖ ﺷﺮﮐﺖ ﻓﻮﻕ ﺩﺭ ﺯﻣﻴﻨﻪ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﭘﺮﺩﺍﺧﺘﻪ ﻭ ﺍﺯ ﺍﻳﻦ ﺭﻫﮕﺬﺭ ﺍﺯ‬ ‫ﺗﺠﺎﺭﺏ ﻣﻮﺟﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬ ‫‪86‬‬

‫‪ Dell‬ﻳﮑﯽ ﺍﺯ ﺻﺪﻫﺎ ﺷﺮﮐﺘﯽ ﺍﺳﺖ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﺷﺨﺼﯽ ﺗﻮﻟﻴﺪﯼ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬

‫ﻣﺸﺘﺮﻳﺎﻥ ﺣﻘﻴﻘﯽ ﻭ ﻳﺎ ﺣﻘﻮﻗﯽ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﺪ‪ .‬ﻓﻌﺎﻟﻴﺖ ﺍﻗﺘﺼﺎﺩﯼ ‪ Dell‬ﺑﺎ ﺩﺭﺝ ﺁﮔﻬﯽ ﺩﺭ ﭘﺸﺖ‬ ‫ﺟﻠﺪ ﻣﺠﻼﺕ ﮐﺎﻣﭙﻴﻮﺗﺮﯼ ﻭ ﻓﺮﻭﺵ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﻃﺮﻳﻖ ﺗﻠﻔﻦ‪ ،‬ﺁﻏﺎﺯ ﮔﺮﺩﻳﺪ‪ .‬ﺍﻣﺮﻭﺯﻩ ﺣﻀﻮﺭ‬ ‫ﺷﺮﮐﺖ ‪ Dell‬ﺩﺭ ﻋﺮﺻﻪ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺴﺮﻋﺖ ﻣﺘﺪﺍﻭﻝ ﻭ ﻋﻤﻮﻣﯽ ﺷﺪﻩ ﺍﺳﺖ‬

‫‪.‬ﺷﺮﮐﺖ ﻓﻮﻕ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﮐﺎﻻﻫﺎﯼ ﺑﻴﺸﻤﺎﺭﯼ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺑﺮ ﺍﺳﺎﺱ ﺁﻣﺎﺭﻫﺎﯼ‬

‫ﻣﻮﺟﻮﺩ ‪ ،‬ﻓﺮﻭﺵ ﺭﻭﺯﺍﻧﻪ ‪ ، Dell‬ﭼﻬﺎﺭﺩﻩ ﻣﻴﻠﻴﻮﻥ ﺩﻻﺭ ﺑﻮﺩﻩ ﻭ ﺗﻘﺮﻳﺒﺎ" ‪ ٢٥‬ﺩﺭﺻﺪ ﻓﺮﻭﺵ ﺍﻳﻦ‬ ‫ﺷﺮﮐﺖ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﺷﺮﮐﺖ ‪ Dell‬ﻗﺒﻞ ﺍﺯ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪،‬‬

‫ﺍﮐﺜﺮ ﺳﻔﺎﺭﺷﺎﺕ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺗﻠﻔﻦ ﺍﺧﺬ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺴﺖ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﯼ ﺧﺮﻳﺪﺍﺭﺍﻥ‬ ‫ﺧﻮﺩ ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﯽ ﮐﺮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻓﺮﻭﺵ ‪ ٢٥‬ﺩﺭﺻﺪﯼ ﺷﺮﮐﺖ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﻣﯽ ﺗﻮﺍﻥ‬

‫ﺑﻪ ﺟﺎﻳﮕﺎﻩ ﻭ ﺍﻫﻤﻴﺖ ﻣﻮﺿﻮﻉ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻴﺶ ﺍﺯ ﮔﺬﺷﺘﻪ ﻭﺍﻗﻒ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ‬ ‫ﺭﺍﺳﺘﺎ ﻣﯽ ﺗﻮﺍﻥ ﺑﻪ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﺍﺷﺎﺭﻩ ﮐﺮﺩ‪:‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺷﺮﮐﺖ ‪ Dell‬ﺗﻮﺍﻧﺴﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﻣﻴﺰﺍﻥ ﻓﺮﻭﺵ ﺍﺯ ﻃﺮﻳﻖ ﺗﻠﻔﻦ ﺭﺍ ‪٢٥‬‬ ‫ﺩﺭﺻﺪ ﮐﺎﻫﺶ ﻭ ‪ ٢٥‬ﺩﺭﺻﺪ ﺑﻪ ﻣﻴﺰﺍﻥ ﻓﺮﻭﺵ ﺧﻮﺩ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺑﻴﻔﺰﺍﻳﺪ ‪ ،‬ﺩﻟﻴﻞ‬ ‫ﺭﻭﺷﻦ ﻭ ﻗﺎﻃﻌﯽ ﺑﺮﺍﯼ ﻭﺟﻮﺩ ﻣﺰﺍﻳﺎﯼ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ؟ ‪Dell‬‬

‫ﺻﺮﻓﺎ" ﮐﺎﻣﭙﻴﻮﺗﺮ ﻋﺮﺿﻪ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﺪﻳﺮﻳﺖ ﻓﺮﻭﺵ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﻫﺰﻳﻨﻪ‬ ‫ﻫﺎﯼ ﮐﻤﺘﺮﯼ ﺭﺍ ﺑﻪ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺗﺤﻤﻴﻞ ﻧﻤﺎﻳﺪ ﻭ ﻳﺎ ﺍﻓﺮﺍﺩﻳﮑﻪ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﮐﺎﻻﯼ‬ ‫ﺧﻮﺩ ﺭﺍ ﺧﺮﻳﺪﺍﺭﯼ ﻣﯽ ﻧﻤﺎﻳﻨﺪ ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺧﺮﻳﺪ ﺗﺠﻬﻴﺰﺍﺕ ﮐﻤﮑﯽ ﺩﻳﮕﺮﯼ ﻧﻤﺎﻳﻨﺪ ﻭ ﻳﺎ‬

‫ﺍﮔﺮ ﻫﺰﻳﻨﻪ ﻫﺎﯼ ﻋﻤﻠﻴﺎﺕ ﻓﺮﻭﺵ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺑﻤﺮﺍﺗﺐ ﮐﻤﺘﺮﺷﺪﻩ ﻭ ﻳﺎ ﺍﮔﺮ ﺍﺭﺍﺋﻪ ﮐﺎﻻ‬ ‫ﺑﺮ ﺭﻭﯼ ﻭﺏ ﺑﺎﻋﺚ ﺍﻓﺰﺍﻳﺶ ﺧﺮﻳﺪﺍﺭﺍﻥ ﻭ ﺣﺠﻢ ﻋﻤﻠﻴﺎﺕ ﻓﺮﻭﺵ ﮔﺮﺩﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺮﺍﯼ ﺷﺮﮐﺖ ‪ Dell‬ﻣﻘﺮﻭﻥ ﺑﺼﺮﻓﻪ ﻭ ﺗﻮﺍﻡ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﺑﻬﺮﻩ ﻭﺭﯼ‬

‫ﺑﻮﺩﻩ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺷﺮﮐﺖ ‪ ، Dell‬ﺩﺭ ﻓﺮﺁﻳﻨﺪ ﻓﺮﻭﺵ ﮐﺎﻻ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ‪ ،‬ﻓﺮﻭﺵ ﺳﻨﺘﯽ ﻭ‬ ‫ﻣﺒﺘﻨﯽ ﺑﺮ ﺗﻠﻔﻦ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﺩﺳﺖ ﻧﺪﻫﺪ‪ ،‬ﭼﻪ ﺍﺗﻔﺎﻗﯽ ﻣﯽ ﺍﻓﺘﺪ؟ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﻣﯽ ﺗﻮﺍﻧﺪ‬ ‫ﺻﺤﺖ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ‪ ،‬ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺑﻪ ﺗﻤﺎﻳﻞ ﻋﺪﻩ ﺍﯼ ﺑﺮﺍﯼ ﺧﺮﻳﺪ ﮐﺎﻻ ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ‬ ‫‪87‬‬

‫ﺑﺴﺘﮕﯽ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﮔﺮﺍﻳﺶ ﺑﺴﻤﺖ ﺧﺮﻳﺪ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺼﻮﺭﺕ ﻳﮏ ﻧﻴﺎﺯ‬

‫ﻣﻄﺮﺡ ﺷﺪﻩ ﺍﺳﺖ ﻭ ﺍﺯ ﺍﻳﻦ ﺑﺎﺑﺖ ﻧﮕﺮﺍﻧﯽ ﭼﻨﺪﺍﻧﯽ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫•‬

‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻓﺮﻭﺵ ﻋﻘﻴﺪﻩ ﺍﯼ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﮐﻪ‪ :‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﻣﺸﺘﺮﯼ ﮐﺎﺭ ﺧﻮﺩ ﺭﺍ ﺑﺎ ﻳﮏ‬ ‫ﻓﺮﻭﺷﻨﺪﻩ ﺁﻏﺎﺯ ﻣﯽ ﻧﻤﺎﻳﺪ‪ ،‬ﻧﮕﻬﺪﺍﺭﯼ ﺁﻥ ﻣﺸﺘﺮﯼ ﺑﺮﺍﯼ ﻓﺮﻭﺷﻨﺪﻩ ﺑﻤﺮﺍﺗﺐ ﺭﺍﺣﺖ ﺗﺮ ﺍﺯ‬ ‫ﺟﺬﺏ ﻣﺸﺘﺮﻳﺎﻥ ﺟﺪﻳﺪ ﺍﺳﺖ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺗﺼﻤﻴﻢ ﺑﻪ ﺍﻳﺠﺎﺩ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ‬

‫ﺯﻭﺩﺗﺮ ﺍﺗﺤﺎﺫ ﮔﺮﺩﺩ‪ ،‬ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﻳﺮ ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﮐﻪ ﺑﻌﺪﺍ" ﺗﺼﻤﻴﻢ ﻓﻮﻕ ﺭﺍ ﺍﺗﺨﺎﺫ‬ ‫ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ ،‬ﭘﻴﺸﻘﺪﻡ ﺧﻮﺍﻫﻴﺪ ﺑﻮﺩ‪ .‬ﺷﺮﮐﺖ ‪ Dell‬ﺳﺎﻳﺖ ﺧﻮﺩ ﺭﺍ ﺧﻴﻠﯽ ﺯﻭﺩ ﻃﺮﺍﺣﯽ‬

‫ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﺍﻳﻦ ﻃﺮﻳﻖ ﺍﺯ ﺳﺎﻳﺮ ﺭﻗﺒﺎﯼ ﺧﻮﺩ ﭘﻴﺸﯽ ﮔﺮﻓﺘﻪ ﺍﺳﺖ‬ ‫ﻋﻮﺍﻣﻞ ﺳﻪ ﮔﺎﻧﻪ ﻓﻮﻕ‪ ،‬ﺩﻻﻳﻞ ﻋﻤﺪﻩ ﺑﺴﻤﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺖ‪.‬‬ ‫ﮔﻴﺮﺍﺋﯽ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﺩﻻﻳﻞ ﺯﻳﺮ ﻋﻠﻞ ﮔﻴﺮﺍﺋﯽ ﻭ ﺟﺎﺫﺑﻪ ﻓﺮﺍﻭﺍﻥ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﮐﺎﻫﺶ ﻫﺰﻳﻨﻪ ﻫﺎ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺨﻮﺑﯽ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﮔﺮﺩﺩ‬ ‫‪ ،‬ﻫﺰﻳﻨﻪ ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﻗﺒﻞ ﺍﺯ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﻭ ﻫﺰﻳﻨﻪ ﻫﺎﯼ ﺧﺪﻣﺎﺕ ﭘﺲ‬ ‫ﺍﺯ ﻓﺮﻭﺵ ﺑﻌﺪ ﺍﺯ ﺍﺭﺍﺋﻪ ﮐﺎﻻ ﮐﺎﻫﺶ ﻣﯽ ﻳﺎﺑﺪ‪.‬‬

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‫ﺧﺮﻳﺪ ﺑﻴﺸﺘﺮ ﺩﺭ ﻫﺮ ﺗﺮﺍﮐﻨﺶ‪ .‬ﺳﺎﻳﺖ ﺁﻣﺎﺯﻭﻥ ﻭﻳﮋﮔﯽ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﺩﻫﺪ ﮐﻪ ﺩﺭ‬ ‫ﻓﺮﻭﺷﮕﺎﻫﻬﺎﯼ ﻣﻌﻤﻮﻟﯽ ﻧﻈﻴﺮ ﺁﻥ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻣﺸﺨﺼﺎﺕ ﻳﮏ ﮐﺘﺎﺏ ﺭﺍ‬

‫ﻣﻄﺎﻟﻌﻪ ﻣﯽ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻣﯽ ﺗﻮﺍﻥ ﺑﺨﺸﯽ ﺑﺎ ﻧﺎﻡ " ﺍﻓﺮﺍﺩﻳﮑﻪ ﮐﺘﺎﺏ ﻓﻮﻕ ﺭﺍ ﺳﻔﺎﺭﺵ ﺩﺍﺩﻩ ﺍﻧﺪ‬ ‫‪ ،‬ﭼﻪ ﭼﻴﺰﻫﺎﯼ ﺩﻳﮕﺮﯼ ﺭﺍ ﺧﺮﻳﺪﺍﺭﯼ ﻧﻤﻮﺩﻩ ﺍﻧﺪ"‪ ،‬ﺭﺍ ﻧﻴﺰ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‬ ‫ﺍﻣﮑﺎﻥ ﻣﺸﺎﻫﺪﻩ ﺳﺎﻳﺮ ﮐﺘﺐ ﻣﺮﺗﺒﻂ ﮐﻪ ﺳﺎﻳﺮﻳﻦ ﺧﺮﻳﺪ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ ،‬ﻓﺮﺍﻫﻢ‬ ‫ﻣﯽ ﮔﺮﺩﺩ‪.‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺧﺮﻳﺪ ﮐﺘﺐ ﺑﻴﺸﺘﺮ ﺗﻮﺳﻂ ﻣﺮﺍﺟﻌﻪ ﮐﻨﻨﺪﮔﺎﻥ ﺑﻪ ﺳﺎﻳﺖ ﻧﺴﺒﺖ‬ ‫ﺑﻪ ﻳﮏ ﮐﺘﺎﺑﻔﺮﻭﺷﯽ ﻣﻌﻤﻮﻟﯽ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺁﻣﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻭﺏ ﺳﺎﻳﺖ ﺑﮕﻮﻧﻪ ﺍﯼ ﻃﺮﺍﺣﯽ ﺷﺪﻩ ﺑﺎﺷﺪ ﮐﻪ ﺑﺎ ﺳﺎﻳﺮ ﻣﺮﺍﺣﻞ ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫ﺗﺠﺎﺭﺕ ﺩﺭﮔﻴﺮ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﺑﻴﺸﺘﺮﯼ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻭﺿﻌﻴﺖ ﮐﺎﻻﯼ‬ ‫ﺧﺮﻳﺪﺍﺭﯼ ﺷﺪﻩ ﺑﺮﺍﯼ ﻣﺸﺘﺮﻳﺎﻥ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺷﺮﮐﺖ‬ ‫‪88‬‬

‫‪ Dell‬ﻭﺿﻌﻴﺖ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺍﺯ ﻣﺮﺣﻠﻪ ﺗﻮﻟﻴﺪ ﺗﺎ ﻋﺮﺿﻪ ‪ ،‬ﺛﺒﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﻣﺸﺘﺮﻳﺎﻥ ﺩﺭ‬

‫ﻫﺮ ﻟﺤﻈﻪ ﻗﺎﺩﺭ ﺑﻪ ﻣﺸﺎﻫﺪﻩ ﺁﺧﺮﻳﻦ ﻭﺿﻌﻴﺖ ﺳﻔﺎﺭﺵ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫•‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﻓﺮﺍﺩ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺘﺨﺎﺏ ﮐﺎﻻﯼ ﺧﻮﺩ ﺑﺎ ﺭﻭﺵ ﻫﺎﯼ‬ ‫ﻣﺘﻔﺎﻭﺗﯽ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﻣﮑﺎﻧﺎﺕ ﺯﻳﺮ ﺭﺍ ﺍﺭﺍﺋﻪ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪:‬‬

‫ ﺍﻣﮑﺎﻥ ﺛﺒﺖ ﻳﮏ ﺳﻔﺎﺭﺵ ﻃﯽ ﭼﻨﺪ ﺭﻭﺯ‬‫ ﺍﻣﮑﺎﻥ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻣﺤﺼﻮﻝ ﻭ ﻣﺸﺎﻫﺪﻩ ﻗﻴﻤﺖ ﻫﺎﯼ ﻭﺍﻗﻌﯽ‬‫ ﺍﻣﮑﺎﻥ ﺍﻳﺠﺎﺩ ﺁﺳﺎﻥ ﺳﻔﺎﺭﺵ ﻫﺎﯼ ﺍﺧﺘﺼﺎﺻﯽ ﭘﻴﭽﻴﺪﻩ‬‫ ﺍﻣﮑﺎﻥ ﻣﻘﺎﻳﺴﻪ ﻗﻴﻤﺖ ﮐﺎﻻ ﺑﻴﻦ ﭼﻨﺪﻳﻦ ﻓﺮﻭﺷﻨﺪﻩ‬‫‪ -‬ﺍﻣﮑﺎﻥ ﺟﺴﺘﺠﻮﯼ ﺁﺳﺎﻥ ﺑﺮﺍﯼ ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬

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‫ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎﯼ ﺑﺰﺭﮔﺘﺮ‪ .‬ﻳﮏ ﺷﺮﮐﺖ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻳﮏ ﮐﺎﺗﻮﻟﻮﮒ ﺑﺮ ﺭﻭﯼ ﻭﺏ ﺑﻮﺩﻩ‬ ‫ﮐﻪ ﻫﺮﮔﺰ ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺁﻥ ﺍﺯ ﻃﺮﻳﻖ ﭘﺴﺖ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻣﺜﻼ" ﺁﻣﺎﺯﻭﻥ ﺑﻴﺶ‬ ‫ﺍﺯ ﺳﻪ ﻣﻴﻠﻴﻮﻥ ﮐﺘﺎﺏ ﺭﺍ ﺑﻔﺮﻭﺵ ﻣﯽ ﺭﺳﺎﻧﺪ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺘﺐ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ‬ ‫ﺳﺎﻳﺖ ﺁﻣﺎﺯﻭﻥ ﺍﺭﺍﺋﻪ ﻭﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺮﺍﺟﻌﻪ ﮐﻨﻨﺪﮔﺎﻥ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ‪ ،‬ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

‫ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ ﭘﺴﺖ‪ ،‬ﺑﺴﻴﺎﺭ ﻣﺸﮑﻞ ﻭ ﻳﺎ ﻏﻴﺮﻣﻤﮑﻦ ﺑﻨﻈﺮ ﻣﯽ ﺁﻳﺪ‪.‬‬ ‫•‬

‫ﺑﻬﺒﻮﺩ ﺍﺭﺗﺒﺎﻁ ﻣﺘﻘﺎﺑﻞ ﺑﺎ ﻣﺸﺘﺮﻳﺎﻥ‪ .‬ﺑﺎ ﻃﺮﺍﺣﯽ ﻣﻨﺎﺳﺐ ﺳﺎﻳﺖ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺑﺰﺍﺭ ﻫﺎﯼ‬ ‫ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﻣﺘﻘﺎﺑﻞ ﺑﺎ ﻣﺸﺘﺮﻳﺎﻥ ﺑﺎ ﺭﻭﺵ ﻫﺎﯼ ﻣﻄﻤﺌﻦ ﺗﺮ ﻭ ﺑﺪﻭﻥ‬ ‫ﺻﺮﻑ ﻫﺰﻳﻨﻪ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ" ﻣﺸﺘﺮﯼ ﭘﺲ ﺍﺯ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﺑﺎ ﺩﺭﻳﺎﻓﺖ ﻳﮏ‬ ‫ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺯ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﺧﻮﺩ ﻣﻄﻤﺌﻦ ﺷﺪﻩ ﻭ ﻳﺎ ﺩﺭ ﺻﻮﺭﺕ ﺍﺭﺳﺎﻝ ﮐﺎﻻ‬ ‫ﺑﺮﺍﯼ ﻣﺸﺘﺮﯼ‪ ،‬ﻣﯽ ﺗﻮﺍﻥ ﺍﺯ ﻃﺮﻳﻖ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭﯼ ﺭﺍ ﻣﻄﻠﻊ ﻧﻤﻮﺩ‪ .‬ﻫﻤﻮﺍﺭﻩ ﻳﮏ‬

‫ﻣﺸﺘﺮﯼ ﺭﺍﺿﯽ ﻭ ﺧﻮﺷﺤﺎﻝ ﺗﻤﺎﻳﻞ ﺑﻪ ﺧﺮﻳﺪ ﻣﺠﺪﺩ ﺍﺯ ﺷﺮﮐﺖ ﻭ ﻳﺎ ﻣﻮﺳﺴﻪ ﺍﺭﺍﺋﻪ‬ ‫ﺩﻫﻨﺪﻩ ﮐﺎﻻ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺫﮐﺮ ﻳﮏ ﻧﮑﺘﻪ ﺩﻳﮕﺮ ﺿﺮﻭﺭﯼ ﺑﻨﻈﺮ ﻣﯽ ﺭﺳﺪ‪ .‬ﺗﺠﺎﺭﺕ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻪ ﺍﻓﺮﺍﺩ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺍﻣﮑﺎﻥ ﺍﻳﺠﺎﺩ ﻣﺪﻝ ﻫﺎﯼ ﮐﺎﻣﻼ" ﺟﺪﻳﺪ ﺗﺠﺎﺭﯼ‬ ‫‪89‬‬

‫ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺷﺮﮐﺖ ﻫﺎﯼ ﺗﺠﺎﺭﯼ ﻣﺒﺘﻨﯽ ﺑﺮ ﺛﺒﺖ ﺳﻔﺎﺭﺵ ﭘﺴﺘﯽ‪ ،‬ﻫﺰﻳﻨﻪ ﻫﺎﯼ ﺯﻳﺎﺩﯼ‬

‫ﺻﺮﻑ ﭼﺎﭖ ﻭ ﺍﺭﺳﺎﻝ ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎ‪ ،‬ﭘﺎﺳﺨﮕﻮﺋﯽ ﺑﻪ ﺗﻠﻔﻦ ﻫﺎ ﻭ ﺭﺩﻳﺎﺑﯽ ﺳﻔﺎﺭﺷﺎﺕ‪،‬‬ ‫ﻣﻴﮕﺮﺩﺩ‪ .‬ﺩﺭ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﻫﺰﻳﻨﻪ ﺗﻮﺯﻳﻊ ﮐﺎﺗﻮﻟﻮﮒ ﻭ ﺭﺩﻳﺎﺑﯽ ﺳﻔﺎﺭﺷﺎﺕ ﺑﺴﻤﺖ ﺻﻔﺮ‬ ‫ﻣﻴﻞ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ ﻋﺮﺿﻪ ﮐﺎﻻ ﺑﺎ ﻗﻴﻤﺖ ﺍﺭﺯﺍﻧﺘﺮ ﻓﺮﺍﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺟﻨﺒﻪ ﻫﺎﯼ ﺳﺎﺩﻩ ﻭ ﺳﺨﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﻣﻮﺍﺭﺩﻳﮑﻪ ﺍﺯ ﺁﻧﻬﺎ ﺑﻌﻨﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﺩﺷﻮﺍﺭ ﻭ ﺳﺨﺖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻳﺎﺩ‬ ‫ﻣﯽ ﺷﻮﺩ ‪ ،‬ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬ ‫•‬

‫ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﺳﺎﻳﺖ‬

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‫ﺗﺮﺍﻓﻴﮏ ﻣﺮﺍﺟﻌﺎﺕ ﺛﺎﻧﻮﻳﻪ ﺑﺮ ﺭﻭﯼ ﺳﺎﻳﺖ‬

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‫ﺗﻤﺎﻳﺰ ﺧﻮﺩ ﺑﺎ ﺳﺎﻳﺮ ﺭﻗﺒﺎﺀ‬

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‫ﺗﻤﺎﻳﻞ ﺍﻓﺮﺍﺩ ﺑﻪ ﺧﺮﻳﺪ ﮐﺎﻻ ﺍﺯ ﺳﺎﻳﺖ ‪.‬ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺎﻳﺖ ﻳﮏ ﻣﻮﺿﻮﻉ ﻭ ﺧﺮﻳﺪ ﺍﺯ ﺳﺎﻳﺖ‬ ‫ﻣﻮﺿﻮﻋﯽ ﺩﻳﮕﺮ ﺍﺳﺖ‪.‬‬

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‫ﺍﺭﺗﺒﺎﻁ ﻭ ﺗﻌﺎﻣﻞ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺎ ﺳﺎﻳﺮ ﺩﺍﺩﻩ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﺎﺯﻣﺎﻥ‬

‫ﺍﻣﺮﻭﺯﻩ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺳﺎﻳﺖ ﻫﺎﯼ ﺑﻴﺸﻤﺎﺭﯼ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﻭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺳﺎﻳﺖ ﺟﺪﻳﺪ‬

‫ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﮐﺎﺭ ﻣﺸﮑﻠﯽ ﻧﻴﺴﺖ ﻭﻟﯽ ﺟﺬﺏ ﻣﺨﺎﻃﺒﻴﻦ ﺟﻬﺖ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺎﻳﺖ ﻭ‬ ‫ﺧﺮﻳﺪ ﺍﺯ ﺁﻥ ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﻣﺴﺌﻠﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ‪.‬‬

‫ﻣﻮﺍﺭﺩﻳﮑﻪ ﺍﺯ ﺁﻧﻬﺎ ﺑﻌﻨﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﺳﺎﺩﻩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻳﺎﺩ ﻣﯽ ﺷﻮﺩ‪،‬‬

‫ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ ‪:‬‬ ‫•‬

‫ﺍﻳﺠﺎﺩ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ‬

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‫ﺍﺧﺬ ﺳﻔﺎﺭﺷﺎﺕ‬

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‫ﭘﺬﻳﺮﺵ ﭘﺮﺩﺍﺧﺖ‬ ‫‪90‬‬

‫ﺍﻳﺠﺎﺩ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﻣﯽ ﺑﺎﻳﺴﺖ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ‬

‫ﮔﻴﺮﺩ‪:‬‬ ‫•‬

‫ﺗﺎﻣﻴﻦ ﮐﻨﻨﺪﮔﺎﻥ ‪ .‬ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﺗﺎﻣﻴﻦ ﮐﻨﻨﺪﮔﺎﻥ ﺧﻮﺏ ﺍﻣﮑﺎﻥ ﻋﺮﺿﻪ ﮐﺎﻻ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ‬ ‫ﺩﺍﺷﺖ‪.‬‬

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‫ﻗﻴﻤﺖ ‪ .‬ﻳﮑﯽ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﺑﺨﺶ ﻫﺎﯼ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﻋﺮﺿﻪ ﮐﺎﻻ ﺑﺎ ﻗﻴﻤﺖ‬

‫ﻣﻨﺎﺳﺐ ﺍﺳﺖ ‪ .‬ﺍﻣﮑﺎﻥ ﻣﻘﺎﻳﺴﻪ ﻗﻴﻤﺖ ﻳﮏ ﮐﺎﻻ ﺑﺴﺎﺩﮔﯽ ﺑﺮﺍﯼ ﻣﺸﺘﺮﻳﺎﻥ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﻭ‬ ‫ﻫﻤﻮﺍﺭﻩ ﻗﻴﻤﺖ ﻳﮏ ﮐﺎﻻ ﺑﺎ ﻣﻮﺍﺭﺩ ﻣﺸﺎﺑﻪ ﮐﻪ ﺍﺯ ﻃﺮﻳﻖ ﺳﺎﻳﺮ ﻓﺮﻭﺷﻨﺪﮔﺎﻥ ﺍﺭﺍﺋﻪ ﻣﯽ ﮔﺮﺩﺩ‬

‫‪ ،‬ﻣﻘﺎﻳﺴﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺑﺎ ﻣﺸﺘﺮﯼ ‪ .‬ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﻣﺘﻨﻮﻉ ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻣﻮﺟﻮﺩ‬ ‫ﺟﻬﺖ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻣﺸﺘﺮﯼ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﭘﺎﻳﮕﺎﻩ ﻫﺎﯼ‬ ‫ﺩﺍﻧﺶ ‪ ،‬ﺗﺎﻻﺭﻫﺎﯼ ﻣﺒﺎﺣﺜﻪ ‪ ،‬ﺍﺗﺎﻕ ﻫﺎﯼ ﮔﻔﺘﮕﻮ ﻭ ‪ ...‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ‬

‫ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺸﺘﺮﯼ ﻫﻤﻮﺍﺭﻩ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺣﺴﺎﺱ ﻧﻤﺎﻳﺪ ﮐﻪ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﻣﺸﮑﻞ ﻭ‬ ‫ﻳﺎ ﺩﺭﺧﻮﺍﺳﺖ ﺍﻃﻼﻋﺎﺕ ﺑﻴﺸﺘﺮ ‪ ،‬ﺑﺪﻭﻥ ﭘﺎﺳﺦ ﻧﺨﻮﺍﻫﻨﺪ ﻣﺎﻧﺪ‪.‬‬ ‫•‬

‫ﺗﻮﺯﻳﻊ ﮐﺎﻻ ‪ ،‬ﺧﺪﻣﺎﺕ ﭘﺲ ﺍﺯ ﻓﺮﻭﺵ ﻭ ﺍﻣﮑﺎﻥ ﺑﺮﮔﺸﺖ ﺍﺯ ﻓﺮﻭﺵ ﺍﺯ ﺟﻤﻠﻪ ﻣﻮﺍﺭﺩﯼ‬ ‫ﺍﺳﺖ ﮐﻪ ﺩﺭ ﻣﻮﻓﻘﻴﺖ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮏ ﻧﻘﺶ ﺑﺴﺰﺍﺋﯽ ﺩﺍﺭﺩ‪.‬‬

‫ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﻗﺎﺑﻠﻴﺖ ﻫﺎﯼ ﺯﻳﺮ ﻧﻴﺰ ﻣﯽ ﺗﻮﺍﻧﺪ ﻋﺮﺿﻪ ﻭ‬ ‫ﺑﺎﻋﺚ ﻣﻮﻓﻘﻴﺖ ﺩﺭ ﺍﻣﺮ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺍﺭﺳﺎﻝ ﻫﺪﻳﻪ ) ﺟﺎﻳﺰﻩ (‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﻫﻤﺒﺴﺘﮕﯽ‬

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‫ﺗﺨﻔﻴﻒ ﻫﺎﯼ ﻭﻳﮋﻩ‬

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‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﺧﺮﻳﺪﺍﺭ ﺗﮑﺮﺍﺭﯼ‬

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‫ﻓﺮﻭﺵ ﺍﺩﻭﺍﺭﯼ ﻭ ﻓﺼﻠﯽ‬ ‫‪91‬‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﻣﮑﺎﻧﺎﺕ ﻓﻮﻕ ﺭﺍ ﻓﺮﺍﻫﻢ ﻧﻤﺎﻳﺪ‪،‬‬ ‫ﺩﺭﻏﻴﺮﺍﻳﻨﺼﻮﺭﺕ ﺍﻧﺠﺎﻡ ﻫﺮ ﻳﮏ ﺍﺯ ﻣﻮﺍﺭﺩ ﻓﻮﻕ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﻫﻤﺒﺴﺘﮕﯽ‬

‫ﻳﮑﯽ ﺍﺯ ﺑﺨﺶ ﻫﺎﯼ ﻣﻬﻢ ﺩﺭ ﺯﻣﻴﻨﻪ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺗﻮﺟﻪ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ‬

‫ﻫﺎﯼ ﻫﻤﺒﺴﺘﮕﯽ ) ﺍﻧﺠﻤﻨﯽ ( ﻣﯽ ﺑﺎﺷﺪ‪ .‬ﻭﻳﮋﮔﯽ ﻓﻮﻕ ﺗﻮﺳﻂ ﺁﻣﺎﺯﻭﻥ ﺑﺨﺪﻣﺖ ﮔﺮﻓﺘﻪ ﺷﺪﻩ‬

‫ﺍﺳﺖ‪ .‬ﺁﻣﺎﺯﻭﻥ ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﻮﺩﻩ ﺗﺎ ﻫﺮ ﺷﺨﺺ ﻗﺎﺩﺭ ﺑﻪ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﻓﺮﻭﺷﮕﺎﻩ‬

‫ﮐﺘﺎﺏ ﺍﺧﺘﺼﺎﺻﯽ ﺑﺎﺷﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺍﺯ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺘﺎﺑﻔﺮﻭﺷﯽ ﻫﺎﯼ ﻓﻮﻕ ‪ ،‬ﮐﺘﺎﺑﯽ ﺧﺮﻳﺪﺍﺭﯼ ﻣﯽ‬ ‫ﮔﺮﺩﺩ‪ ،‬ﻓﺮﺩﯼ ﮐﻪ ﺩﺍﺭﺍﯼ ﮐﺘﺎﺑﻔﺮﻭﺷﯽ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ ‪ ،‬ﮐﻤﻴﺴﻴﻮﻧﯽ ) ﺣﺪﺍﮐﺜﺮ ‪ ١٥‬ﺩﺭﺻﺪ ﻗﻴﻤﺖ‬

‫ﮐﺘﺎﺏ ( ﺭﺍ ﺍﺯ ﺁﻣﺎﺯﻭﻥ ﺩﺭﻳﺎﻓﺖ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﻤﺒﺴﺘﮕﯽ‪ ،‬ﻗﺎﺑﻠﻴﺖ ﻫﺎﯼ ﺯﻳﺎﺩﯼ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬

‫ﺁﻣﺎﺯﻭﻥ ﻗﺮﺍﺭ ﻣﯽ ﺩﻫﺪ ‪ .‬ﻣﺪﻝ ﻓﻮﻕ ﺍﻣﺮﻭﺯﻩ ﺗﻮﺳﻂ ﻫﺰﺍﺭﺍﻥ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﻳﮕﺮ‬ ‫ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﺍﺯ ﺁﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

‫ﻳﮑﯽ ﺍﺯ ﮔﺮﺍﻳﺸﺎﺕ ﺟﺪﻳﺪ ﺩﺭ ﺯﻣﻴﻨﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﻫﻤﺒﺴﺘﮕﯽ‪ ،‬ﺭﻭﺵ ‪Cost Per(CPC link‬‬ ‫‪ (click‬ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺑﺮ ﺭﻭﯼ ﺳﺎﻳﺖ‪ ،‬ﻳﮏ ﻟﻴﻨﮏ ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﺎﻳﺖ ﺩﻳﮕﺮ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﺑﺮ ﺭﻭﯼ ﻟﻴﻨﮏ ﻓﻮﻕ ﮐﻠﻴﮏ ﮔﺮﺩﺩ‪ ،‬ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﺷﻤﺎ ﻣﺒﻠﻐﯽ ﭘﺮﺩﺍﺧﺖ‬

‫ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺵ ﻓﻮﻕ‪ ،‬ﻣﺪﻟﯽ ﻣﻴﺎﻧﻪ ﺑﻴﻦ ﺭﻭﺵ ﻫﺎﯼ ﺗﺒﻠﻴﻐﺎﺗﯽ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ Banner‬ﻭ ﺑﺮﻧﺎﻣﻪ‬

‫ﻫﺎﯼ ﻫﻤﺒﺴﺘﮕﯽ ﻣﺒﺘﻨﯽ ﺑﺮ ﮐﻤﻴﺴﻴﻮﻥ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺭﻭﺵ ﺗﺒﻠﻴﻐﺎﺗﯽ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ ،Banner‬ﺷﺮﮐﺖ‬

‫ﺗﺒﻠﻴﻎ ﮐﻨﻨﺪﻩ ﺗﻤﺎﻡ ﺭﻳﺴﮏ ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻓﺮﺩﯼ ﺑﺮ ﺭﻭﯼ ‪Banner‬‬ ‫ﮐﻠﻴﮏ ﻧﻨﻤﺎﻳﺪ‪ ،‬ﺗﺒﻠﻴﻎ ﮐﻨﻨﺪﻩ ﭘﻮﻝ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﺩﺳﺖ ﺩﺍﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺭﻭﺵ ﺍﺧﺬ ﮐﻤﻴﺴﻴﻮﻥ‪ ،‬ﺗﻤﺎﻡ‬ ‫ﺭﻳﺴﮏ ﺑﺮ ﻋﻬﺪﻩ ﻭﺏ ﺳﺎﻳﺖ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻭﺏ ﺳﺎﻳﺖ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﯼ ﻣﺸﺘﺮﯼ ﺭﺍ ﺑﻪ‬ ‫ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺭﺳﺎﻝ ) ﻫﺪﺍﻳﺖ ( ﻭﻟﯽ ﻫﻴﭽﮑﺪﺍﻡ ﺍﺯ ﺁﻧﻬﺎ ﮐﺎﻻﺋﯽ ﺭﺍ ﺧﺮﻳﺪﺍﺭﯼ‬ ‫ﻧﻨﻤﺎﻳﻨﺪ ‪ ،‬ﻣﺒﻠﻐﯽ ﺑﻪ ﻭﺏ ﺳﺎﻳﺖ ﭘﺮﺩﺍﺧﺖ ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ‪ CPC‬ﺩﻭ ﻃﺮﻑ ﺭﻳﺴﮏ‬

‫ﻣﻮﺟﻮﺩ ﺭﺍ ﺑﺼﻮﺭﺕ ﻣﺸﺘﺮﮎ ﻗﺒﻮﻝ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮏ‬

‫ﺳﻪ ﺭﻭﺵ ﻋﻤﺪﻩ ﺑﺮﺍﯼ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻳﮏ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮏ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪:‬‬ ‫•‬

‫‪ . Enterprise Computing‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺷﺮﮐﺖ ﻭ ﻳﺎ ﻣﻮﺳﺴﻪ ﻣﺮﺑﻮﻁ‬ ‫ﺍﻗﺪﺍﻡ ﺑﻪ ﺗﻬﻴﻪ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻭ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﻭﺭﺯﻳﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻭﺏ‬

‫ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺧﻮﺩ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺁﻣﺎﺯﻭﻥ ﻭ ﺳﺎﻳﺮ ﺷﺮﮐﺖ ﻫﺎﯼ ﺑﺰﺭﮒ ﺍﺯ‬ ‫ﺭﻭﺵ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻧﺘﺨﺎﺏ ﺭﻭﺵ ﻓﻮﻕ ﻣﺸﺮﻭﻁ ﺑﻪ ﻭﺟﻮﺩ ﻋﻮﺍﻣﻞ ﺯﻳﺮ‬

‫ﺍﺳﺖ‬

‫ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﯼ ﺗﺮﺍﻓﻴﮏ ﺑﺴﻴﺎﺭ ﺑﺎﻻﺋﯽ ﺍﺳﺖ ) ﭼﻨﺪﻳﻦ ﻣﻴﻠﻴﻮﻥ ﺩﺭ ﻫﺮ ﻣﺎﻩ (‬‫‪ -‬ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﯼ ﻳﮏ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﯽ ﺑﺰﺭﮒ ﺑﻮﺩﻩ ﮐﻪ ﺷﺎﻣﻞ ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎﯼ‬

‫ﻣﺮﺑﻮﻁ ﺑﻪ ﻣﺤﺼﻮﻻﺕ ﺍﺳﺖ ) ﻣﺨﺼﻮﺻﺎ" ﺍﮔﺮ ﮐﺎﺗﻮﻟﻮﮒ ﻫﺎ ﺑﺴﺮﻋﺖ ﺗﻐﻴﻴﺮﻣﯽ ﻳﺎﺑﻨﺪ(‪.‬‬ ‫ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﯼ ﻳﮏ ﭼﺮﺧﻪ ﻓﺮﻭﺵ ﭘﻴﭽﻴﺪﻩ ﺑﻮﺩﻩ ﮐﻪ ﻣﺴﺘﻠﺰﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﻡ‬‫ﻫﺎﯼ ﺍﺧﺘﺼﺎﺻﯽ ‪ ،‬ﺟﺪﺍﻭﻝ ﻣﺘﻔﺎﻭﺕ ﻗﻴﻤﺖ ﻭ ‪ ...‬ﺍﺳﺖ ‪.‬‬

‫ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﯼ ﺳﺎﻳﺮ ﭘﺮﺩﺍﺯﺵ ﻫﺎﯼ ﺗﺠﺎﺭﯼ ﺑﻮﺩﻩ ﻭ ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﻭﭘﻴﻮﺳﺘﮕﯽ‬‫ﺁﻧﻬﺎ ﺑﺎ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬ ‫•‬

‫ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﻣﻴﺰﺑﺎﻧﯽ ﻣﺠﺎﺯﯼ ‪ .‬ﻓﺮﻭﺷﻨﺪﻩ ﺗﺠﻬﻴﺰﺍﺕ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺭﺍ‬

‫ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺑﺴﺘﻪ ﻧﺮﻡ ﺍﻓﺰﺍﺭﯼ ﺍﺧﺘﺼﺘﺎﺻﯽ ﻋﺮﺿﻪ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺨﺸﯽ ﺍﺯ ﺑﺴﺘﻪ ﻧﺮﻡ‬

‫ﺍﻓﺰﺍﺭﯼ ﺷﺎﻣﻞ ﺍﻣﻨﻴﺖ ﺍﺳﺖ ‪ .‬ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﯽ ﻧﻴﺰ ﺑﺨﺶ ﺩﻳﮕﺮﯼ ﺍﺯ ﺑﺴﺘﻪ‬ ‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﯼ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﺩﺍﻣﻪ ﺷﺮﮐﺖ ﻣﺮﺑﻮﻃﻪ‬

‫ﻣﯽ ﺗﻮﺍﻧﺪ ﺑﺎ ﺑﺨﺪﻣﺖ ﮔﺮﻓﺘﻦ ﻃﺮﺍﺣﺎﻥ ﻭﺏ ﻭ ﭘﻴﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﻳﺠﺎﺩ ﻭ‬ ‫ﻧﮕﻬﺪﺍﺭﯼ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺧﻮﺩ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺳﺎﺩﻩ ‪ .‬ﺍﮐﺜﺮ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﺷﺮﮐﺖ ﻫﺎ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﺑﺮﺍﯼ ﭘﻴﺎﺩﻩ‬

‫ﺳﺎﺯﯼ ﺳﺎﻳﺖ ﺗﺠﺎﺭﺕ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬ﺳﻴﺴﺘﻢ ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ‬

‫ﻓﺮﻡ ﻫﺎﯼ ﺳﺎﺩﻩ ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﻣﺘﻘﺎﺿﯽ ﺗﮑﻤﻴﻞ ﻣﯽ ﮔﺮﺩﻧﺪ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﺮﺑﻮﻃﻪ ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﺗﻤﺎﻡ ﺻﻔﺤﺎﺕ ﻭﺏ ﺫﻳﺮﺑﻂ ﺭﺍ ﺗﻮﻟﻴﺪ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪93‬‬

‫ﻳﺎﺩﮔﻴﺮﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﻋﺮﺻﻪ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﻧﻴﺰ ﭼﺎﻟﺶ ﻫﺎﯼ ﺟﺪﻳﺪﯼ ﺭﺍ ﺍﻳﺠﺎﺩ ﮐﺮﺩﻩ ﺍﺳﺖ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺯﻳﺮﺳﺎﺧﺖ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺮﺍﯼ ﺁﻣﻮﺯﺵ‪ ،‬ﺩﺭ ﺳﺎﻟﻴﺎﻥ ﺍﺧﻴﺮ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﻭ‬ ‫ﻣﺮﺍﮐﺰ ﻋﻠﻤﯽ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺍﺳﺖ‪ .‬ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﺁﻣﻮﺯﺵ ﻣﺒﺘﻨﯽ ﺑﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ )‪،(CBT‬‬ ‫ﺁﻣﻮﺯﺵ ﻣﺒﺘﻨﯽ ﺑﺮ ﺍﻳﻨﺘﺮﻧﺖ )‪ (IBT‬ﻭ ﺁﻣﻮﺯﺵ ﻣﺒﺘﻨﯽ ﺑﺮ ﻭﺏ )‪ (WBT‬ﻧﻤﻮﻧﻪ ﺍﺳﺎﻣﯽ ﺍﻧﺘﺨﺎﺏ‬ ‫ﺷﺪﻩ ﺑﺮﺍﯼ ﺭﻭﺵ ﻫﺎﯼ ﺟﺪﻳﺪ ﺁﻣﻮﺯﺷﯽ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺁﻣﻮﺯﺵ ) ﻳﺎﺩ ﺩﺍﺩﻥ ﻭ ﻳﺎﺩ ﮔﻴﺮﯼ (‪ ،‬ﻃﯽ‬

‫ﺳﺎﻟﻴﺎﻥ ﺁﻳﻨﺪﻩ ﺑﺎ ﺍﻧﻘﻼﺑﯽ ﺑﺰﺭﮒ ﺭﻭﺑﺮﻭ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺍﻣﮑﺎﻧﺎﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﯼ ﻭ ﻧﺮﻡ ﺍﻓﺮﺍﺭﯼ‬ ‫ﻣﻮﺟﻮﺩ‪ ،‬ﺑﺸﺮﻳﺖ ﺭﺍ ﺑﻪ ﺳﻤﺖ ﻳﮏ ﺍﻧﻘﻼﺏ ﺑﺰﺭﮒ ﺁﻣﻮﺯﺷﯽ ﺳﻮﻕ ﻣﯽ ﺩﻫﺪ‪.‬‬ ‫ﺁﻣﻮﺯﺵ ﻫﺎﯼ ‪ Online‬ﺍﺯ ﺳﺎﻝ ‪ ١٩٩٠‬ﻣﻄﺮﺡ ﻭ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﺷﺪ ﺗﺠﻬﻴﺰﺍﺕ ﻭ ﺍﻣﮑﺎﻧﺎﺕ‬

‫ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﺩﻫﻪ ﮔﺬﺷﺘﻪ‪ ،‬ﮔﺎﻡ ﻫﺎﯼ ﻣﻮﺛﺮﯼ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﺮﺩﺍﺷﺘﻪ ﺷﺪﻩ ﻭ ﺍﻳﻨﮏ ﺩﺭ ﻧﻘﻄﻪ‬ ‫ﻋﻄﻔﯽ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺍﺳﺖ‪ .‬ﺁﺷﻨﺎﺋﯽ ﺑﺎ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﺟﺪﻳﺪ ﺑﺮﺍﯼ ﺗﻤﺎﻣﯽ ﺩﺳﺖ‬ ‫ﺍﻧﺪﺭﮐﺎﺭﺍﻥ ﺍﻣﺮ ﺁﻣﻮﺯﺵ‪ ،‬ﺣﺎﺋﺰ ﺍﻫﻤﻴﺖ ﺍﺳﺖ‪ .‬ﺍﮔﺮ ﺩﺍﻧﺎﺋﯽ ﺭﺍ ﻋﻴﻦ ﺗﻮﺍﻧﺎﺋﯽ ﺑﺪﺍﻧﻴﻢ ‪ ،‬ﺟﻮﺍﻣﻌﯽ ﺍﺯ‬

‫ﺑﺸﺮﻳﺖ ﺑﻪ ﺗﻮﺍﻧﺎﺋﯽ ﻭ ﺧﻮﺩ ﺑﺎﻭﺭﯼ ﺧﻮﺍﻫﻨﺪ ﺭﺳﻴﺪ ﮐﻪ ﺯﻳﺮ ﺳﺎﺧﺖ ﻣﻨﺎﺳﺒﯽ ﺭﺍ ﺑﺮﺍﯼ ﺳﻴﺴﺘﻢ‬ ‫ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﺧﻮﺩ ﺍﻧﺘﺨﺎﺏ ﻭ ﺑﺮ ﻫﻤﻴﻦ ﺍﺳﺎﺱ ﺣﺮﮐﺎﺕ ﻫﺪﻓﻤﻨﺪ ﻭ ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﺁﻣﻮﺯﺷﯽ ﺭﺍ‬ ‫ﺑﺎ ﺗﺎﮐﻴﺪ ﺑﺮ ﻋﻨﺎﺻﺮ ﻣﺘﻔﺎﻭﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺳﻴﺴﺘﻢ ﺁﻣﻮﺯﺷﯽ‪ ،‬ﺁﻏﺎﺯ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺁﻣﻮﺯﺵ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻓﺮﺻﺖ ﻣﻨﺎﺳﺒﯽ ﺭﺍ ﺑﺮﺍﯼ ﺗﻤﺎﻣﯽ ﺩﺳﺖ ﺍﻧﺪﺭﮐﺎﺭﺍﻥ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﻓﺮﺍﻫﻢ‬ ‫ﻧﻤﻮﺩﻩ ﺍﺳﺖ ﺗﺎ ﺑﺘﻮﺍﻧﻨﺪ ﺑﺎ ﺑﻬﺮﻩ ﮔﻴﺮﯼ ﺍﺯ ﺁﺧﺮﻳﻦ ﻓﻦ ﺁﻭﺭﯼ ﻫﺎﯼ ﻣﻮﺟﻮﺩ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﺭﺳﺎﻟﺖ‬ ‫ﺧﻮﺩ ﺭﺍ ﮐﻪ ﻫﻤﺎﻥ ﺁﻣﻮﺯﺵ ﺍﺳﺖ ﺑﺎ ﺳﺮﻋﺖ ﻭﮐﻴﻔﻴﺘﯽ ﻣﻄﻠﻮﺏ ﺩﺭﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﺩﻫﻨﺪ‪.‬‬ ‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﭼﻴﺴﺖ ؟‬

‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﺍﻣﮑﺎﻥ ﻓﺮﺍﮔﻴﺮﯼ ﻣﺴﺘﻘﻞ ﺍﺯ ﺯﻣﺎﻥ ﻭ ﻣﮑﺎﻥ ﺭﺍ ﺑﺮﺍﯼ ﺩﺍﻧﺶ ﭘﮋﻭﻫﺎﻥ ﻓﺮﺍﻫﻢ‬ ‫ﻣﯽ ﺁﻭﺭﺩ‪ .‬ﺟﺎﻳﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺴﻴﺎﺭ ﺣﺎﺋﺰ ﺍﻫﻤﻴﺖ ﺍﺳﺖ‪.‬‬ ‫ﺑﺎ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻣﻨﺎﺳﺐ ﮐﺎﻣﭙﻴﻮﺗﺮ)ﺳﺨﺖ ﺍﻓﺰﺍﺭ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻭ ﺷﺒﮑﻪ(‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻣﻮﺯﺵ ﻫﺎﯼ‬

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‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺮﺍﯼ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻥ ﻓﺮﺍﻫﻢ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻋﻤﻠﮑﺮﺩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺁﻣﻮﺯﺵ ﻫﺎﯼ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻧﻈﻴﺮ ﻋﻤﻠﮑﺮﺩ ﻣﻮﺑﺎﻳﻞ ﺩﺭ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻣﻨﺎﺳﺐ‬ ‫ﻣﻮﺑﺎﻳﻞ ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﻣﺴﺘﻘﻞ ﺍﺯ ﺯﻣﺎﻥ ﻭ ﻣﮑﺎﻥ ﺧﺎﺹ ﺑﺮﺍﯼ ﺍﻓﺮﺍﺩ ﺑﻮﺟﻮﺩ ﻣﯽ ﺁﻳﺪ‪.‬‬ ‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﺗﻮﺍﻧﺪ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ ، CD-ROM‬ﺷﺒﮑﻪ‪ ،‬ﺍﻳﻨﺘﺮﺍﻧﺖ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎﺷﺪ‪.‬‬

‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺮﺍﯼ ﺍﺭﺍﺋﻪ ﻣﺤﺘﻮﯼ ﺍﺯ ﻋﻨﺎﺻﺮ ﺍﻃﻼﻋﺎﺗﯽ ﺑﺎ ﻓﺮﻣﺖ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﻧﻈﻴﺮ‪:‬‬ ‫ﻣﺘﻦ ‪ ،‬ﻭﻳﺪﺋﻮ ‪ ،‬ﺻﺪﺍ‪ ،‬ﺍﻧﻴﻤﻴﺸﻦ‪ ،‬ﮔﺮﺍﻓﻴﮏ ﻭ ﻣﺤﻴﻂ ﻫﺎﯼ ﻣﺠﺎﺯﯼ ﻭ ﻳﺎ ﺷﺒﻴﻪ ﺳﺎﺯﯼ ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺗﺠﺎﺭﺏ ﺑﺪﺳﺖ ﺁﻣﺪﻩ ﺍﺯ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻤﺮﺍﺗﺐ ﮔﺴﺘﺮﺩﻩ ﺗﺮ ﺍﺯ ﺗﺠﺎﺭﺏ‬ ‫ﺁﻣﻮﺯﺷﯽ ﺑﺪﺳﺖ ﺁﻣﺪﻩ ﺩﺭ ﻳﮏ ﮐﻼﺱ ﺩﺭﺱ ﺳﻨﺘﯽ ﺍﺳﺖ ‪ .‬ﺁﻫﻨﮓ ﻓﺮﺍﮔﻴﺮﯼ ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﯼ‬

‫ﺁﻣﻮﺯﺷﯽ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺯ ﻳﮏ ﺭﻭﻧﺪ ﻣﺸﺨﺺ ﻭ ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﺗﺒﻌﻴﺖ ﮐﺮﺩﻩ ﻭ ﻣﺨﺎﻃﺒﺎﻥ ﺧﻮﺩ‬ ‫ﺭﺍ ﺑﺎ ﻫﺮ ﻧﻮﻉ ﺳﻠﻴﻘﻪ ﻭ ﮔﺮﺍﻳﺶ ﺑﺴﺮﻋﺖ ﺟﺬﺏ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﻣﺰ ﻣﻮﻓﻘﻴﺖ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺷﻴﻮﻩ ﺍﺭﺍﺋﻪ‪ ،‬ﻧﻮﻉ ﻣﺤﺘﻮﻳﺎﺕ ﻭ ﺗﻮﺯﻳﻊ‬ ‫) ﻋﺮﺿﻪ ( ﻣﻨﺎﺳﺐ ﻣﯽ ﺩﺍﻧﻨﺪ‪ .‬ﺩﺭ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺯ ﺍﻏﻠﺐ ﻣﺴﺎﺋﻞ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺳﻨﺘﯽ ﻧﻈﻴﺮ ‪ :‬ﺳﺨﻨﺮﺍﻧﯽ ﻫﺎﯼ ﻳﮑﻄﺮﻓﻪ‪ ،‬ﺗﻌﺎﻣﻞ ﻭ ﺍﺭﺗﺒﺎﻁ ﺿﻌﻴﻒ ﺑﺎ ﻓﺮﺍﮔﻴﺮﺍﻥ‪،‬‬ ‫ﺍﺟﺘﻨﺎﺏ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﻣﯽ ﺗﻮﺍﻥ ﺑﺴﺮﻋﺖ ﻣﺤﻴﻂ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﻣﻮﺛﺮ ﻭ ﮐﺎﺭﺁ ﺭﺍ ﺑﺎ ﺑﻬﺮﻩ ﮔﻴﺮﯼ ﺍﺯ ﻋﻨﺎﺻﺮ ﻣﺘﻔﺎﻭﺕ‬ ‫ﺁﻣﻮﺯﺷﯽ ﺍﻳﺠﺎﺩ ﮐﺮﺩ‪.‬‬ ‫ﺳﻄﻮﺡ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﭼﻬﺎﺭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﻃﺒﻘﻪ ﺑﻨﺪﯼ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﮔﺮﻭﻩ ﻫﺎﯼ ﻓﻮﻕ ﺳﻄﻮﺡ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺁﻣﻮﺯﺷﯽ ﺍﺯ ﺍﺑﺘﺪﺍﺋﯽ ﺗﺎ ﺳﻄﻮﺡ ﭘﻴﺸﺮﻓﺘﻪ ﺭﺍ ﺗﻀﻤﻴﻦ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪:‬‬ ‫•‬

‫ﭘﺎﻳﮕﺎﻩ ﻫﺎﯼ ﺩﺍﻧﺶ ‪ .‬ﭘﺎﻳﮕﺎﻩ ﻫﺎﯼ ﺩﺍﻧﺶ ﻭ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺩ ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺁﻣﻮﺯﺵ ﻭﺍﻗﻌﯽ‬ ‫ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻧﻤﯽ ﺷﻮﻧﺪ‪ .‬ﺑﺎﻧﮏ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ ﺷﮑﻞ ﺍﻭﻟﻴﻪ ﺍﯼ ﺍﺯ ﺁﻣﻮﺯﺵ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺎﻧﮏ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ ﻓﻮﻕ ﺭﺍ ﻣﯽ ﺗﻮﺍﻥ ﺩﺭ ﺳﺎﻳﺖ ﻫﺎﯼ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﯼ ﻣﺘﻌﺪﺩ‪ ،‬ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪ .‬ﺑﺎﻧﮏ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ ﺑﺎ ﻳﮏ ﺭﻭﺵ‬ ‫ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﺗﻮﺿﻴﺤﺎﺕ ﻭ ﺭﺍﻫﻨﻤﺎﺋﯽ ﻫﺎﯼ ﺿﺮﻭﺭﯼ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬ ‫‪95‬‬

‫ﺳﻮﺍﻻﺕ ﻣﻄﺮﺡ ﺷﺪﻩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ‬

‫ﻫﺎﯼ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺹ ﺗﻮﺳﻂ ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺑﺼﻮﺭﺕ ﻣﺮﺣﻠﻪ ﺑﻪ‬ ‫ﻣﺮﺣﻠﻪ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺘﻘﺎﺿﻴﺎﻥ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ‪.‬ﺑﺎﻧﮏ ﻫﺎﯼ ﺍﻃﻼﻋﺎﺗﯽ ﻓﻮﻕ ‪ ،‬ﺍﻏﻠﺐ‬ ‫ﺑﺼﻮﺭﺕ ﻣﺘﻌﺎﻣﻞ ﺑﺎ ﮐﺎﺭﺑﺮﺍﻥ ﺧﻮﺩ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﺜﻼ" ﮐﺎﺭﺑﺮﺍﻥ ﻣﯽ ﺗﻮﺍﻧﻨﺪ‬

‫ﮐﻠﻤﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺑﺨﺶ ﻣﺮﺑﻮﻃﻪ ﺗﺎﻳﭗ ﺗﺎ ﺯﻣﻴﻨﻪ ﺟﺴﺘﺠﻮ ﺩﺭ ﺑﺎﻧﮏ‬

‫ﺍﻃﻼﻋﺎﺗﯽ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺍﻣﮑﺎﻥ ﺍﻧﺘﺨﺎﺏ ﻣﻮﺿﻮﻉ ﻣﻮﺭﺩ ﻋﻼﻗﻪ ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﻟﻴﺴﺖ ﻫﺎﯼ ﻣﺮﺗﺐ ﺷﺪﻩ ) ﻣﻮﺿﻮﻋﯽ ﻭ ﻳﺎ ﺍﻟﻔﺒﺎﺋﯽ ( ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬

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‫ﺣﻤﺎﻳﺖ ﻓﻨﯽ ‪ . online‬ﺣﻤﺎﻳﺖ ‪ online‬ﻧﻴﺰ ﻧﻮﻉ ﺧﺎﺻﯽ ﺍﺯ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬ ‫ﺑﻮﺩﻩ ﮐﻪ ﺩﺭ ﻣﻮﺍﺭﺩﯼ ﺷﺒﺎﻫﺖ ﻫﺎﺋﯽ ﺑﺎ ﭘﺎﻳﮕﺎﻩ ﻫﺎﯼ ﺩﺍﻧﺶ ‪ ،‬ﺩﺍﺭﺩ‪ .‬ﺑﺮﺍﯼ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ‬ ‫ﺣﻤﺎﻳﺖ ﻫﺎﯼ ﻓﻨﯽ ‪ ، online‬ﺍﺯ ﺭﻭﺵ ﻫﺎﯼ ﻣﺘﻌﺪﺩﯼ ﻧﻈﻴﺮ ‪ :‬ﺗﺎﻻﺭﻫﺎﯼ ﻣﺒﺎﺣﺜﻪ‪ ،‬ﺍﺗﺎﻕ‬

‫ﻫﺎﯼ ﮔﻔﺘﮕﻮ‪ ،‬ﺳﻴﺴﺘﻢ ﻫﺎﯼ ‪ ، BBS‬ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﻳﺎ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﻓﻮﺭﯼ ﻭ ﺯﻧﺪﻩ‬ ‫‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻓﻮﻕ ﺗﻌﺎﻣﻞ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﯼ ﺭﺍ ﻧﺴﺒﺖ ﺑﻪ ﭘﺎﻳﮕﺎﻩ‬ ‫ﻫﺎﯼ ﺩﺍﻧﺶ ﺑﺎ ﻣﺨﺎﻃﺐ ‪ ،‬ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺁﻣﻮﺯﺵ ﻧﺎﻣﺘﻘﺎﺭﻥ ‪ .‬ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﺩﺭ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻭﻟﻴﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﯽ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺧﻮﺩ ﺁﻣﻮﺯﯼ ﺑﺎ ﻣﺤﻮﺭﻳﺖ ﻓﺮﺍﮔﻴﺮﺍﻥ ﻓﺮﺍﻫﻢ‬

‫ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺍﯼ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻭ ﺍﺟﺮﺍﯼ ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻭ ﺭﻭﺵ ﻫﺎﯼ‬

‫ﻣﺘﻌﺪﺩﯼ ﻧﻈﻴﺮ‪ :‬ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﻣﺒﺘﻨﯽ ﺑﺮ ‪ ، CD-ROM‬ﺍﻳﻨﺘﺮﺍﻧﺖ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻳﮏ ﻋﻤﻠﻴﺎﺕ‬

‫ﺧﺎﺹ ﺍﺯ ﻃﺮﻳﻖ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ‪ ، BBS‬ﮔﺮﻭﻩ ﻫﺎ ﻭ ﺗﺎﻻﺭﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﻣﺒﺎﺣﺜﻪ ﻭ ﭘﺴﺖ‬

‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻓﻮﻕ ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺩﺭ ﺑﺮﺧﯽ ﻣﻮﺍﺭﺩ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻓﻮﻕ‪ ،‬ﺑﺼﻮﺭﺕ ﮐﺎﻣﻼ" ﺧﻮﺩ ﺁﻣﻮﺯ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﻟﻴﻨﮏ ﻫﺎﯼ‬

‫ﺧﺎﺻﯽ ﺑﺮﺍﯼ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﻣﻨﺎﺑﻊ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭﺍﻳﻦ ﻧﻮﻉ ﺳﻴﺴﺘﻢ ﻫﺎ‪ ،‬ﺍﺯ‬ ‫ﻣﺮﺑﻴﺎﻥ ﺁﻣﻮﺯﺷﯽ ﮐﻪ ﺑﺼﻮﺭﺕ ﺯﻧﺪﻩ ﻓﻌﺎﻟﻴﺖ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺭﺍ ﻣﺪﻳﺮﻳﺖ‬

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‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﯽ ﮔﺮﺩﺩ‪ .‬ﭼﺎﺭﭼﻮﺏ ﻭ ﺳﺎﺧﺘﺎﺭ ﺍﺭﺍﺋﻪ ﻣﻮﺿﻮﻉ ﻭ ﻣﺤﺘﻮﯼ ﺍﻏﻠﺐ‬ ‫ﺑﺼﻮﺭﺕ ﺧﻮﺩﺁﻣﻮﺯ ﺑﺎ ﻫﺪﺍﻳﺖ ﻟﻴﻨﮏ ﻫﺎﯼ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺩﺭ ﻣﻮﺿﻮﻋﺎﺕ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪.‬‬

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‫ﺁﻣﻮﺯﺵ ﻫﻤﺰﻣﺎﻥ ‪ .‬ﺁﻣﻮﺯﺵ ﻫﻤﺰﻣﺎﻥ ﺑﺼﻮﺭﺕ ﺑﻼﺩﺭﻧﮓ ﺑﺎ ﮐﻤﮏ ﻳﮏ ﻣﺮﺑﯽ ﺁﻣﻮﺯﺷﯽ‬ ‫ﮐﻪ ﺑﺼﻮﺭﺕ ﺯﻧﺪﻩ ﻧﺎﻇﺮ ﺗﻤﺎﻡ ﻓﻌﺎﻟﻴﺖ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺍﺳﺖ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪.‬‬

‫ﺩﺭ ﺳﻴﺴﺘﻢ ﻓﻮﻕ‪ ،‬ﻓﺮﺍﮔﻴﺮﺍﻥ ﺑﺎ ﻭﺭﻭﺩ ﺑﻪ ﮐﻼﺱ ﻣﺠﺎﺯﯼ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ‬ ‫ﻣﺴﺘﻘﻴﻢ ﺑﺎ ﻣﺮﺑﯽ ﻭ ﺳﺎﻳﺮ ﻓﺮﺍﮔﻴﺮﺍﻥ ﻣﻮﺟﻮﺩ ﺩﺭ ﮐﻼﺱ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﺗﻤﺎﻡ ﻭﻳﮋﮔﯽ ﻫﺎﯼ ﻳﮏ ﮐﻼﺱ ﺩﺭﺱ ﺑﺼﻮﺭﺕ ﻣﺠﺎﺯﯼ ﺷﺒﻴﻪ‬ ‫ﺳﺎﺯﯼ ﻭ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺮﺑﯽ ﻭ ﻓﺮﺍﮔﻴﺮﺍﻥ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﻣﺜﻼ" ﻣﯽ ﺗﻮﺍﻥ ﺑﺼﻮﺭﺕ ﻣﺠﺎﺯﯼ‬ ‫ﺩﺳﺖ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﯼ ﺳﻮﺍﻝ ﮐﺮﺩﻥ ﺑﺎﻻ ﺑﺮﺩﻩ ﻭ ﻳﺎ ﺣﺘﯽ ﺍﺯ ﻳﮏ ﺗﺨﺘﻪ ﺳﻴﺎﻩ ﻣﺠﺎﺯﯼ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﻣﺤﺘﻮﻳﺎﺕ ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﺑﺮ ﺭﻭﯼ ﺁﻥ ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪ .‬ﺟﻠﺴﺎﺕ ﺁﻣﻮﺯﺷﯽ‬

‫ﻣﻤﮑﻦ ﺍﺳﺖ ﺻﺮﻓﺎ" ﺩﺭ ﺣﺪ ﻭ ﺍﻧﺪﺍﺯﻩ ﻳﮏ ﺟﻠﺴﻪ ﺑﻮﺩﻩ ﻭ ﻳﺎ ﻫﻔﺘﻪ ﻫﺎ‪ ،‬ﻣﺎﻩ ﻫﺎ ﻭ ﻳﺎ ﺣﺘﯽ‬ ‫ﺳﺎﻝ ﻫﺎ‪ ،‬ﺑﻄﻮﻝ ﺍﻧﺠﺎﻣﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺁﻣﻮﺯﺵ ﻫﺎ ﻣﻌﻤﻮﻻ" ﺍﺯ ﻃﺮﻳﻖ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﯼ‬

‫ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﮐﻨﻔﺮﺍﻧﺲ ﻫﺎﯼ ﺻﻮﺗﯽ ﻭ ﻳﺎ ﺗﺼﻮﻳﺮﯼ ‪ ،‬ﺍﻳﻨﺘﺮﻧﺖ ﺗﻠﻔﻨﯽ ﺍﻧﺠﺎﻡ ﻣﯽ ﮔﻴﺮﺩ‪.‬‬ ‫ﺭﻭﺍﻧﺸﻨﺎﺳﯽ ﻳﺎﺩﮔﻴﺮﯼ‬

‫ﭼﻪ ﻧﻮﻉ ﺗﺤﻮﻻﺕ ﻭ ﻳﺎ ﺍﺗﻔﺎﻗﺎﺗﯽ ﺩﺭ ﻣﻐﺰ ﺍﻧﺴﺎﻥ ﺩﺭ ﺯﻣﺎﻥ ﻓﺮﺍﮔﻴﺮﯼ‪ ،‬ﺑﻮﺟﻮﺩ ﻣﯽ ﺁﻳﺪ؟ ﺁﻣﻮﺯﺵ‬

‫ﺩﺭ ﺍﺑﺘﺪﺍ ﻧﻴﺎﺯﻣﻨﺪ ﻣﺤﺮﮎ ﻫﺎﯼ ﻻﺯﻡ ﺍﺳﺖ ‪.‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﺮﺍﮔﻴﺮﯼ ﻣﻮﺛﺮ ﻭ ﮐﺎﺭﺁ ‪ ،‬ﻣﺤﺮﮎ ﻫﺎﯼ‬ ‫ﻣﻮﺟﻮﺩ ﻣﯽ ﺑﺎﻳﺴﺖ ﻧﮕﻬﺪﺍﺭﯼ ﮔﺮﺩﻧﺪ‪ .‬ﻣﺘﺎﺳﻔﺎﻧﻪ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻧﺮﻭﻧﯽ )ﻋﺼﺒﯽ( ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﻐﺰ‬ ‫ﮐﻪ ﻣﺴﺌﻮﻝ ﮐﻨﺘﺮﻝ ﻣﺤﺮﮎ ﻫﺎ ﻭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﯼ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺣﺎﻓﻈﻪ ﻣﯽ ﺑﺎﺷﺪ‪ ،‬ﺑﺴﺮﻋﺖ ﺩﭼﺎﺭ‬ ‫ﺧﺴﺘﮕﯽ ﻣﯽ ﮔﺮﺩﻧﺪ )ﭘﺲ ﺍﺯ ﮔﺬﺷﺖ ﭼﻨﺪ ﺩﻗﻴﻘﻪ(‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺁﻧﻬﺎ ﻧﻴﺎﺯﻣﻨﺪ ﺑﺎﺯﺳﺎﺯﯼ ﺩﺭ‬

‫ﻓﻮﺍﺻﻞ ﺑﻴﻦ ﺳﻪ ﺗﺎ ﭘﻨﺞ ﺩﻗﻴﻘﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ ،‬ﺩﺭ ﻏﻴﺮ ﺍﻳﻨﺼﻮﺭﺕ ﻣﻴﺰﺍﻥ ﭘﺎﺳﺨﮕﻮﺋﯽ ﻭ ﻓﺮﺍﮔﻴﺮﯼ ﺁﻧﻬﺎ‬ ‫ﺩﭼﺎﺭ ﺍﻓﺖ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺁﻧﻬﺎ ﺑﺴﺮﻋﺖ ﺑﺎﺯﺳﺎﺯﯼ ﻣﯽ ﮔﺮﺩﻧﺪ‪ ،‬ﺳﻴﺴﺘﻢ ﺁﻣﻮﺯﺷﯽ ﻣﯽ ﺑﺎﻳﺴﺖ‬

‫ﺑﺴﺮﻋﺖ ﺑﺎ ﺧﺴﺘﮕﯽ ﻭ ﺩﻟﺰﺩﮔﯽ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ ﺑﺮﺍﯼ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺑﺮﺧﻮﺭﺩ ﻣﻨﺎﺳﺐ ﺭﺍ ﺩﺍﺷﺘﻪ ‪ ،‬ﺗﺎ‬ ‫ﺍﻣﮑﺎﻥ ﻳﺎﺩﮔﻴﺮﯼ ﻣﻮﺛﺮﺗﺮ ﺑﻮﺟﻮﺩ ﺁﻳﺪ‪.‬‬

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‫ﻳﺎﺩﮔﻴﺮﯼ ﺑﺮ ﺍﺳﺎﺱ ﺍﻟﮕﻮ ﻫﺎ‪ ،‬ﻣﻮﺛﺮﺗﺮﻳﻦ ﻣﺪﻝ ﻳﺎﺩﮔﻴﺮﯼ ﻣﺤﺴﻮﺏ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ‪،‬‬

‫ﺍﻟﮕﻮﻫﺎ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺍﯼ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺩﻳﮕﺮ ﺟﺎﺑﺠﺎ ﻣﯽ ﮔﺮﺩﻧﺪ‪ .‬ﺍﻟﮕﻮﻫﺎﺋﯽ ﮐﻪ ﻧﺮﻭﻥ ﻫﺎﯼ ﻣﺮﺑﻮﻁ‬

‫ﺑﺨﻮﺩ ﺭﺍ ﻣﺴﺌﻮﻝ ﭘﺎﺳﺨﮕﻮﺋﯽ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ ،‬ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﻣﺘﻔﺎﻭﺕ ﺩﺭ ﻣﺤﻞ ﻫﺎﯼ ﻣﺘﻔﺎﻭﺕ ﻣﻐﺰ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﻣﺜﻼ"‬ ‫•‬

‫ﮔﻮﺵ ﺩﺍﺩﻥ ﺑﻪ ﻳﮏ ﺣﻘﻴﻘﺖ ‪ .‬ﺯﻣﺎﻧﻴﮏ ﺁﺭﺩ ﺑﺎ ﺗﺨﻢ ﻣﺮﻍ ﺗﺮﮐﻴﺐ ﻣﯽ ﮔﺮﺩﺩ‪ ،‬ﺧﻤﻴﺮﯼ‬ ‫ﺑﻮﺟﻮﺩ ﻣﯽ ﺁﻳﺪ ﮐﻪ ﻣﯽ ﺗﻮﺍﻥ ﺁﻥ ﺭﺍ ﺑﻪ ﻗﻄﻌﺎﺗﯽ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻣﺎﮐﺎﺭﻭﻧﯽ ﺑﺮﺵ ﺩﺍﺩ‪.‬‬

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‫ﺍﺭﺗﺒﺎﻁ ﻳﮏ ﻣﻔﻬﻮﻡ ﺑﺎ ﻳﮏ ﺣﻘﻴﻘﺖ ‪ .‬ﻏﺬﺍ ﮐﻪ ﺩﺍﺭﺍﯼ ﮐﺮﺑﻮﻫﻴﺪﺭﺍﺕ ﺑﺎﻻﺋﻲ ﺍﺳﺖ‪ ،‬ﺑﺮﺍﯼ‬ ‫ﺗﻮﻟﻴﺪ ﺍﻧﺮﮊﯼ ﺑﺪﻥ ﻻﺯﻡ ﺍﺳﺖ‪.‬‬

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‫ﺗﺠﺴﻢ ﺩﻭ ﭼﻴﺰ ﺑﺎﻳﮑﺪﻳﮕﺮ ‪ .‬ﺗﻴﻢ ﻫﺎﯼ ﻭﺭﺯﺷﯽ ﺑﻪ ﺍﻧﺮﮊﯼ ﺳﺮﻳﻊ ﻧﻴﺎﺯ ﺩﺍﺷﺘﻪ ﻭ ﺁﻥ ﺭﺍ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﮐﺮﺑﻮﻫﻴﺪﺭﺍﺕ ﺗﺎﻣﻴﻦ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻨﻦ ﻗﺒﻞ ﺍﺯ ﺑﺎﺯﯼ ﻳﮏ ﻭﻋﺪﻩ ﻏﺬﺍ ﻣﻨﺎﺳﺐ‬

‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻓﻮﻕ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﻫﻤﮑﺎﺭﯼ ﺑﺎﻳﮑﺪﻳﮕﺮ ﺣﺎﻓﻈﻪ ﺭﺍ ﺷﮑﻞ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ ) ﻳﺎﺩﮔﻴﺮﯼ ( ﻫﺪﻑ ﺷﮑﻞ ﺩﻫﯽ ﺣﺎﻓﻈﻪ‪ ،‬ﺩﺭ ﻫﺮﻳﮏ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻧﺮﻭﻧﯽ‬ ‫ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺍﻃﻼﻋﺎﺗﯽ ﮐﻪ ﺑﮕﻮﻧﻪ ﺍﯼ ﻃﺮﺍﺣﯽ ﻣﯽ ﮔﺮﺩﻧﺪ ﺗﺎ ﺍﺯ ﻳﮏ ﺳﻴﺴﺘﻢ ﻧﺮﻭﻧﯽ‬ ‫ﺑﻪ ﺳﻴﺴﺘﻢ ﻧﺮﻭﻧﯽ ﺩﻳﮕﺮ ﺣﺮﮐﺖ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺩﺍﺭﺍﯼ ﮐﺎﺭﺁﺋﯽ ﺑﻴﺸﺘﺮﯼ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻳﺎﺩﮔﻴﺮﯼ‬

‫ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻳﺎﺩﮔﻴﺮﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﻧﮕﻬﺪﺍﺷﺖ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﻬﺒﻮﺩ ﻣﯽ ﺑﺨﺸﺪ ؟‬

‫ﺁﻣﻮﺯﺵ ﻋﻼﻭﻩ ﺑﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﻧﺮﻭﻧﯽ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ‪ ،‬ﻣﺴﺘﻠﺰﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻋﻨﺎﺻﺮ ﺩﻳﮕﺮ‬

‫ﻧﻈﻴﺮ ‪ :‬ﺍﺭﺗﺒﺎﻁ ﻣﺘﻘﺎﺑﻞ‪ ،‬ﺗﺨﻴﻞ ﻭ ﻓﻴﺪﺑﮏ ﺍﺳﺖ‪ .‬ﻳﺎﺩﮔﻴﺮﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻋﻨﺎﺻﺮ‬

‫ﻣﺘﻔﺎﻭﺕ‪ ،‬ﮐﻪ ﺑﺎﻋﺚ ﺍﻳﺠﺎﺩ ﻋﻨﺎﺻﺮ ﺟﺪﻳﺪ ﺁﻣﻮﺯﺷﯽ ﻣﯽ ﮔﺮﺩﺩ ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﻓﺮﺍﮔﻴﺮﯼ ﺭﺍ ﺣﺬﺍﺏ ﺗﺮ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺍﻳﺠﺎﺩ ﺟﺬﺍﺑﻴﺖ ﺩﺭ ﻳﺎﺩﮔﻴﺮﯼ ﻳﮑﯽ ﺍﺯ ﺩﻻﻳﻞ ﻣﻮﻓﻘﻴﺖ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﺍﺳﺖ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺍﺯ ﻋﻨﺎﺻﺮ ﺟﺪﻳﺪ ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﯼ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻧﮕﺮﺩﺩ‪،‬‬

‫ﻋﻤﻼ" ﺟﺬﺍﺑﻴﺖ ﻫﺎﯼ ﻻﺯﻡ ﺑﺮﺍﯼ ﺁﻣﻮﺯﺵ ﺭﺍ ﺍﺯ ﺩﺳﺖ ﺩﺍﺩﻩ ﺍﻳﻢ‪ .‬ﺑﺮﺍﯼ ﻣﻮﻓﻘﻴﺖ ﺩﺭ ﺁﻣﻮﺯﺵ‬

‫ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻧﮑﺎﺕ ﺯﻳﺮ ﻣﯽ ﺑﺎﻳﺴﺖ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ ﮔﻴﺮﺩ‪.‬‬ ‫‪98‬‬

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‫ﺑﺮﺭﺳﯽ ﻧﻮﻉ ﻣﺤﺘﻮﻳﺎﺕ ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﺼﺎﻭﻳﺮ‪ ،‬ﺻﺪﺍ ﻭ ﻣﺘﻦ ﻭ ﺗﺮﮐﻴﺐ ﻣﻨﺎﺳﺐ ﺁﻧﻬﺎ ﺑﺎ‬

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‫ﺍﺭﺗﺒﺎﻁ ﻣﺘﻔﺎﺑﻞ ﺑﺎ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺑﮕﻮﻧﻪ ﺍﯼ ﮐﻪ ﺍﻳﺠﺎﺩ ﻣﺤﺮﮎ ﻫﺎﯼ ﻻﺯﻡ ﺭﺍ ﺗﻀﻤﻴﻦ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻳﮑﺪﻳﮕﺮ ﭘﻴﺎﻣﺪﻫﺎﯼ ﻣﺜﺒﺘﯽ ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺎﺯﻳﻬﺎ ‪ ،‬ﺍﻣﺘﺤﺎﻧﺎﺕ ﮐﻮﺗﺎﻩ ﻣﺪﺕ ﺑﺮﺍﯼ ﺍﺧﺬ ﻓﻴﺪﺑﮏ ﺳﺮﻳﻊ ﺍﺯ ﻓﺮﺍﮔﻴﺮﺍﻥ‬ ‫ﻣﻨﺎﺳﺐ ﺗﺮﻳﻦ ﺭﻭﺵ ﺑﺮﺍﯼ ﺳﻨﺠﺶ ﻣﻴﺰﺍﻥ ﻣﻮﻓﻘﻴﺖ ﺩﺭ ﺁﻣﻮﺯﺵ ﺍﺳﺖ‪.‬‬

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‫ﺍﻳﺠﺎﺩ ﻓﻴﺪﺑﮏ ﻫﺎﯼ ﺳﺮﻳﻊ ‪ .‬ﺩﻭﺭﻩ ﻫﺎﯼ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﺭﻭﺵ ﻫﺎﺋﯽ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺧﺬ ﻓﻴﺪ ﺑﮏ ﺳﺮﻳﻊ ﺍﺳﺘﻔﺎﺩﻩ ﺗﺎ ﺩﺭ ﺻﻮﺭﺕ ﺍﺷﮑﺎﻝ ﻭ ﻳﺎ ﻋﺪﻡ ﻣﻮﻓﻘﻴﺖ‪،‬‬ ‫ﺳﺮﻳﻌﺎ" ﻧﺴﺒﺖ ﺑﻪ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻥ ﺁﻥ ﺍﻗﺪﺍﻡ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻓﻴﺪﺑﮏ ﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﻣﯽ ﺑﺎﻳﺴﺖ‬ ‫ﺩﺭ ﺳﺮﻳﻌﺘﺮﻳﻦ ﺯﻣﺎﻥ ﻣﻤﮑﻦ ﺍﺧﺬ ﮔﺮﺩﻧﺪ‪ .‬ﺁﻣﻮﺯﺵ ﺩﺭ ﻫﺮ ﻣﺮﺣﻠﻪ ﺑﺮ ﺍﺳﺎﺱ ﺁﻣﻮﺯﺵ ﺩﺭ‬ ‫ﻣﺮﺣﻠﻪ ﻗﺒﻞ ﺍﻳﺠﺎﺩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﺸﺨﻴﺺ ﻭ ﺍﺧﺬ ﻓﻴﺪﺑﮏ ﻫﺎﯼ ﺳﺮﻳﻊ‪ ،‬ﻣﺮﺍﺣﻞ‬

‫ﻣﺘﻔﺎﻭﺕ ﺁﻣﻮﺯﺷﯽ ﺭﺍ ﺑﺪﺭﺳﺘﯽ ﺗﺒﻴﻦ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺩﺭ ﻳﮏ ﻣﺮﺣﻠﻪ‬

‫ﻣﻮﻓﻘﻴﺘﯽ ﺣﺎﺻﻞ ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﻣﺮﺣﻠﻪ ﺑﻌﺪ ﮐﻪ ﺑﺮ ﺍﺳﺎﺱ ﻣﺮﺣﻠﻪ ﻗﺒﻞ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪،‬‬ ‫ﺩﺭ ﺍﻣﺮ ﺁﻣﻮﺯﺵ ﺗﻮﻓﻴﻖ ﭼﻨﺪﺍﻧﯽ ﺍﻳﺠﺎﺩ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺻﻤﻴﻤﯽ ﺑﺎ ﺳﺎﻳﺮ ﻓﺮﺍﮔﻴﺮﺍﻥ ﻭ ﻣﺮﺑﻴﺎﻥ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺗﺎﻕ ﻫﺎﯼ‬ ‫ﮔﻔﺘﮕﻮ‪ ،‬ﺗﺎﻻﺭﻫﺎﯼ ﻣﺒﺎﺣﺜﻪ‪ ،‬ﭘﻴﺎﻡ ﻫﺎﯼ ﻓﻮﺭﯼ ﻭ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ‬ ‫ﻣﺘﻘﺎﺑﻞ ﺑﺎ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺴﻴﺎﺭ ﻣﻮﺛﺮ ﻭ ﮐﺎﺭﺳﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺍﻳﺠﺎﺩ ﮐﻤﻴﺘﻪ ﻫﺎﯼ‬ ‫‪ Online‬ﺑﻄﺮﺯ ﭼﺸﻤﮕﻴﺮﯼ ﺩﺭ ﻋﻤﻠﮑﺮﺩ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﺁﻣﻮﺯﺷﯽ ﺗﺎﺛﻴﺮ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﻪ ﻓﺮﺍﮔﻴﺮﺍﻥ ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ﺗﺎ ﻫﺮ ﻓﺮﺩ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫ﻣﺴﺎﻳﻞ ﻭ ﺗﻮﺍﻧﺎﺋﯽ ﺧﻮﺩ‪ ،‬ﺁﻫﻨﮓ ﻳﺎﺩﮔﻴﺮﯼ ﺭﺍ ﺧﻮﺩ ﻣﺸﺨﺺ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﯼ‪ ،‬ﻓﺮﺍﮔﻴﺮﺍﻥ‬ ‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﻪ ﺩﻻﻳﻠﯽ‪ ،‬ﭼﻨﺪ ﺭﻭﺯﯼ ﺍﺯ ﺳﻴﺴﺘﻢ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻨﻤﺎﻳﻨﺪ ﻭ ﺍﺯ ﺁﻣﻮﺯﺵ ﺩﻭﺭ ﺑﺎﺷﻨﺪ‪،‬‬

‫ﭘﺲ ﺍﺯ ﺑﺮﻃﺮﻑ ﺷﺪﻥ ﻣﺸﮑﻼﺕ‪ ،‬ﻣﺠﺪﺩﺍ" ﻗﺎﺩﺭ ﺑﻪ ﺍﺩﺍﻣﻪ ﺁﻣﻮﺯﺵ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﻭﺭﻩ ﻫﺎﯼ‬ ‫ﺁﻣﻮﺯﺷﯽ ﻣﺒﺘﻨﯽ ﺑﺮ ﺁﻣﻮﺯﺵ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺍﺭﺍﯼ ﻋﻨﺎﺻﺮ ﻗﺎﺑﻞ ﮐﻨﺘﺮﻟﯽ ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﻧﺪ‪ .‬ﻋﻨﺎﺻﺮ ﮐﻨﺘﺮﻟﯽ ﻓﻮﻕ ﺩﺭ ﮐﻼﺱ ﻫﺎ ﯼ ﺁﻣﻮﺯﺵ ﻣﻌﻤﻮﻟﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻧﺸﺪﻩ ﻭ‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﺩﺭ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﻓﺮﺍﮔﻴﺮﺍﻥ ﻗﺎﺩﺭ ﺑﻪ ﮐﻨﺘﺮﻝ ﻓﺮﺁﻳﻨﺪ ﺁﻣﻮﺯﺵ‪،‬‬ ‫‪99‬‬

‫ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻗﺎﺑﻠﻴﺖ ﺗﻨﻈﻴﻢ ﺁﻫﻨﮓ ﺁﻣﻮﺯﺵ ﺗﻮﺳﻂ ﻓﺮﺍﮔﻴﺮﺍﻥ ﻳﮑﯽ ﺍﺯ ﺩﻻﻳﻞ ﻣﻬﻢ ﺩﺭ ﺭﺍﺑﻄﻪ‬

‫ﺑﺎ ﻣﻮﺛﺮ ﺑﻮﺩﻥ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺖ‪.‬‬

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‫ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬ ‫ﺷﻬﺮﻭﻧﺪﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺭﻭﺯﺍﻧﻪ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﺑﺮﺍﯼ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻣﺒﺎﺩﻟﻪ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻳﮑﯽ ﺍﺯ ﺍﻭﻟﻴﻦ ﺳﺮﻭﻳﺲ ﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺤﺴﻮﺏ ﺷﺪﻩ ﻭ ﺍﻣﺮﻭﺯﻩ‬ ‫ﺍﺯ ﺁﻥ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﺍﺑﺰﺍﺭ ﺍﺭﺗﺒﺎﻃﯽ ﻗﺪﺭﺗﻤﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﻳﮏ ﻧﺎﻣﻪ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﮔﺴﺘﺮﺩﻩ ﻭ ﻣﺴﻴﺮﯼ ﻃﻮﻻﻧﯽ ﻃﯽ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻳﮏ ﭘﻴﺎﻡ ‪E-Mail‬‬

‫ﺍﻭﻟﻴﻦ ﭘﻴﺎﻡ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺳﺎﻝ ‪ ١٩٧١‬ﺗﻮﺳﻂ ﻣﻬﻨﺪﺳﯽ ﺑﺎ ﻧﺎﻡ " ‪Ray‬‬ ‫‪ "Tomlinson‬ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﻗﺒﻞ ﺍﺯ ﺗﺤﻘﻖ ﺭﻭﻳﺪﺍﺩ ﻓﻮﻕ ‪ ،‬ﺻﺮﻓﺎ" ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ‬

‫ﺑﺮﺍﯼ ﮐﺎﺭﺑﺮﺍﻥ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺴﺮ ﺑﻮﺩ‪ .‬ﭘﻴﺎﻡ ﺍﺭﺳﺎﻟﯽ ﺗﻮﺳﻂ ‪Tomlinson‬‬

‫ﻗﺎﺑﻠﻴﺖ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﻪ ﺳﺎﻳﺮ ﻣﺎﺷﻴﻦ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻋﻼﻣﺖ‬ ‫"@" ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻣﺎﺷﻴﻦ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺑﻮﺩ‪ ، E-Mail .‬ﻳﮏ ﭘﻴﺎﻡ ﻣﺘﻨﯽ ﺳﺎﺩﻩ‬ ‫ﺍﺳﺖ ﮐﻪ ﺑﺮﺍﯼ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﺍﺭﺳﺎﻝ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﻨﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺍﺑﺘﺪﺍ ﻭ ﻫﻢ ﺍﻳﻨﮏ‬

‫ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ﻣﺘﻦ ﻫﺎﯼ ﮐﻮﺗﺎﻩ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺑﺮﺧﯽ ﻣﻮﺍﺭﺩ ﻣﻤﮑﻦ ﺍﺳﺖ‪ ،‬ﻓﺮﺳﺘﻨﺪﮔﺎﻥ ﻧﺎﻣﻪ‬ ‫ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺎ ﺍﻓﺰﻭﺩﻥ "ﺿﻤﺎﺋﻢ "‪ ،‬ﺣﺠﻢ ﻳﮏ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﺍﻓﺰﺍﻳﺶ ﺩﻫﻨﺪ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ‪E-mail‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺎﻫﺪﻩ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ‪ ،‬ﻣﯽ ﺑﺎﻳﺴﺖ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﺳﺮﻭﻳﺲ‬ ‫ﮔﻴﺮﻧﺪﻩ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻣﻌﺮﻭﻑ‬

‫‪ outlook‬ﻭ ﻳﺎ ‪ outlook express‬ﺷﺮﮐﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ‪ Eudora ،‬ﻭ ﻳﺎ‬ ‫‪ Pegasus‬ﺑﻤﻨﻄﻮﺭ ﻣﺸﺎﻫﺪﻩ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻓﺮﺍﺩﻳﮑﻪ ﺍﺯ‬ ‫ﺧﺪﻣﺎﺕ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍﻳﮕﺎﻥ ﻧﻈﻴﺮ ‪ Hotmail‬ﻭ ﻳﺎ ‪ Yahoo‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﺯ‬

‫ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﮐﻪ ﺑﺼﻮﺭﺕ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﯽ ﺷﻮﺩ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬

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‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﻧﻮﻉ ﺧﻮﺩ ‪ ،‬ﺩﺍﺭﺍﯼ ﻭﻇﺎﻳﻒ ﺯﻳﺮ‬

‫ﻣﯽ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫ﻧﻤﺎﻳﺶ ﻟﻴﺴﺖ ﺗﻤﺎﻡ ﭘﻴﺎﻡ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺻﻨﺪﻭﻕ ﭘﺴﺘﯽ ﺍﺯ ﻃﺮﻳﻖ " ﻋﻨﺎﻭﻳﻦ ﭘﻴﺎﻡ ﻫﺎ " ‪.‬‬ ‫ﻋﻨﻮﺍﻥ ﻳﮏ ﭘﻴﺎﻡ ﻣﺸﺨﺺ ﮐﻨﻨﺪﻩ ﻓﺮﺳﺘﻨﺪﻩ‪ ،‬ﻣﻮﺿﻮﻉ‪ ،‬ﺗﺎﺭﻳﺦ ﻭ ﺯﻣﺎﻥ ﻭ ﺍﻧﺪﺍﺯﻩ ﭘﻴﺎﻡ ﺍﺳﺖ‪.‬‬

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‫ﺍﻣﮑﺎﻥ ﺍﻧﺘﺨﺎﺏ ﻳﮏ ﭘﻴﺎﻡ ﺍﺯ ﻃﺮﻳﻖ ﻋﻨﻮﺍﻥ ﺁﻥ ﻓﺮﺍﻫﻢ ﺷﺪﻩ ﻭﻣﻄﺎﻟﻌﻪ ﻣﺤﺘﻮﻳﺎﺕ ﭘﻴﺎﻡ‬

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‫ﺍﻣﮑﺎﻥ ﺍﻳﺠﺎﺩ ﭘﻴﺎﻡ ﻫﺎﯼ ﺟﺪﻳﺪ ﻭ ﺍﺭﺳﺎﻝ ﺁﻧﻬﺎ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﻳﮏ‬ ‫ﭘﻴﺎﻡ ﻣﯽ ﺑﺎﻳﺴﺖ ﺁﺩﺭﺱ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﻣﻮﺿﻮﻉ ﭘﻴﺎﻡ ﺭﺍ ﻣﺸﺨﺺ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﺤﺘﻮﻳﺎﺕ ﭘﻴﺎﻡ‬ ‫ﺭﺍ ﺗﺎﻳﭗ ﮐﺮﺩ‪.‬‬

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‫ﺍﮐﺜﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﻣﮑﺎﻥ ﺍﺿﺎﻓﻪ ﮐﺮﺩﻥ ﺿﻤﺎﺋﻢ ﺑﻪ‬ ‫ﻳﮏ ﭘﻴﺎﻡ ﺭﺍ ﻧﻴﺰ ﻓﺮﺍﻫﻢ ﻣﯽ ﺁﻭﺭﻧﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﻓﻮﻕ ﻫﻤﭽﻨﻴﻦ ﺍﻣﮑﺎﻥ ﺫﺧﻴﺮﻩ ﮐﺮﺩﻥ‬

‫ﺿﻤﺎﺋﻢ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﻴﺎﻡ ﻫﺎﯼ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺭﺍ ﻧﻴﺰ ﺩﺍﺭﺍ ﻣﯽ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺳﺎﺩﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻳﮏ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻣﻮﺟﻮﺩ ﻣﯽ ﺑﺎﻳﺴﺖ ﺑﻪ ﻳﮏ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﺮﺗﺒﻂ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺧﯽ ﺍﺯ ﻣﺎﺷﻴﻦ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﻧﺼﺐ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻻﺯﻡ ﺑﻌﻨﻮﺍﻥ " ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ " ﺩﺭ ﺷﺒﮑﻪ ﺍﻳﻔﺎﯼ ﻭﻇﻴﻔﻪ‬ ‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، telnet‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ Ftp‬ﻭ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﯽ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎﯼ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻓﻌﺎﻟﻴﺖ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ ﻧﺼﺐ ﺷﺪﻩ ﺑﺮ ﺭﻭﯼ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺑﺼﻮﺭﺕ ﺷﺒﺎﻧﻪ ﺭﻭﺯﯼ ﺩﺭ ﺣﺎﻟﺖ ﺍﺟﺮﺍﺀ ﺑﻮﺩﻩ ﻭ ﺑﻪ ﭘﻮﺭﺕ ﻫﺎﯼ ﺧﺎﺻﯽ‬ ‫ﮔﻮﺵ ﻓﺮﺍ ﻣﯽ ﺩﻫﻨﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺩﺭ ﺍﻧﺘﻈﺎﺭ ﺍﺭﺗﺒﺎﻁ ﺳﺎﻳﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ) ﺳﺮﻭﻳﺲ‬

‫ﮔﻴﺮﻧﺪﮔﺎﻥ( ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ﻣﺮﺑﻮﻃﻪ ﻣﯽ ﺑﺎﺷﻨﺪ‪ .‬ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺭ ﺳﺎﺩﻩ ﺗﺮﻳﻦ ) ﺣﺎﻟﺖ ﺁﻣﻮﺯﺷﯽ ( ﺣﺎﻟﺖ ﺑﺼﻮﺭﺕ ﺯﻳﺮ ﻋﻤﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪:‬‬ ‫‪102‬‬

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‫ﻫﺮ ﺷﺨﺺ ﺑﺮ ﺭﻭﯼ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺍﺭﺍﯼ ﻳﮏ ‪ Account‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻭ‬

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‫ﺑﺮﺍﯼ ﻫﺮ ﻳﮏ ﺍﺯ ﺍﻓﺮﺍﺩﻳﮑﻪ ﺩﺍﺭﺍﯼ ‪ Account‬ﻣﯽ ﺑﺎﺷﻨﺪ‪ ،‬ﻳﮏ ﻓﺎﻳﻞ ﺳﺎﺩﻩ ﻣﺘﻨﯽ ﺩﺭ‬

‫ﺩﺭﻳﺎﻓﺖ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺖ‪.‬‬

‫ﻓﻮﻟﺪﺭ ﻣﻮﺭﺩ ﻧﻈﺮ ﺫﺧﻴﺮﻩ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬

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‫ﺍﻓﺮﺍﺩﻳﮑﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺮﺍﯼ ﺷﺨﺺ ﺑﺨﺼﻮﺻﯽ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪،‬‬ ‫ﻣﯽ ﺑﺎﻳﺴﺖ ﻳﮏ ﭘﻴﺎﻡ ﻣﺘﻨﯽ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﭘﺲ ﺍﺯ ﺁﻣﺎﺩﻩ ﻧﻤﻮﻥ ﭘﻴﺎﻡ ‪ ،‬ﺑﺎ ﻓﺸﺮﺩﻥ ﺩﮐﻤﻪ "ﺍﺭﺳﺎﻝ"‪ ،‬ﭘﻴﺎﻡ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﯼ ﮔﻴﺮﻧﺪﻩ‬ ‫ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻭ ﭘﻴﺎﻡ ﺣﺎﻭﯼ ﺁﺩﺭﺱ ﻓﺮﺳﺘﻨﺪﻩ‪ ،‬ﮔﻴﺮﻧﺪﻩ ﻭ ﻣﺤﺘﻮﻳﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﺮﺍﯼ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﻃﻼﻋﺎﺕ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺭﺍ ﺑﺎ ﻳﮏ ﻓﺮﻣﺖ ﻣﻨﺎﺳﺐ ﺑﻪ‬ ‫ﺍﻧﺘﻬﺎﯼ ﻓﺎﻳﻞ ﻣﺘﻨﯽ ﮐﻪ ﺑﺮﺍﯼ ﻫﺮ ﻓﺮﺩ ﺑﺎ ﻧﺎﻡ ‪ Account‬ﻭﯼ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‪ ،‬ﺍﺿﺎﻓﻪ‬ ‫ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﻃﻼﻋﺎﺕ ﺩﻳﮕﺮ ﻧﻈﻴﺮ ‪ :‬ﺯﻣﺎﻥ ﻭ ﺗﺎﺭﻳﺦ ﺩﺭﻳﺎﻓﺖ ﭘﻴﺎﻡ ﺭﺍ ﻧﻴﺰ‬

‫ﺫﺧﻴﺮﻩ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﻳﮕﺮ ﺑﺮﺍﯼ ﻳﮏ ﮔﻴﺮﻧﺪﻩ‬

‫ﺧﺎﺹ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﻴﺎﻡ ﻫﺎﯼ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺭﺍ ﺑﻪ ﺍﻧﺘﻬﺎﯼ ﻓﺎﻳﻞ ﻣﺘﻨﯽ )ﺣﺎﻭﯼ‬ ‫ﭘﻴﺎﻡ ﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ( ﺍﺿﺎﻓﻪ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ‬ ‫ﮔﻴﺮﻧﺪﻩ ﺧﻮﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﻭ ﻣﺸﺎﻫﺪﻩ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪":‬‬

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‫ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﯽ ﺧﻮﺍﻫﺪ ﮐﻪ ﻳﮏ ﻧﺴﺨﻪ ﺍﺯ ﻓﺎﻳﻞ ﻣﺘﻨﯽ‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺨﺺ ﮔﻴﺮﻧﺪﻩ ﺭﺍ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﯽ ﺧﻮﺍﻫﺪ ﮐﻪ ﻣﺤﺘﻮﻳﺎﺕ ﻓﺎﻳﻞ ﻣﺘﻨﯽ ﺭﺍ‬ ‫ﺣﺬﻑ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻗﺎﺩﺭ ﺑﻪ ﺫﺧﻴﺮﻩ ﺳﺎﺯﯼ ﻓﺎﻳﻞ ﻣﺘﻨﯽ ﺣﺎﻭﯼ ﭘﻴﺎﻡ ﻫﺎ ﺑﺮ ﺭﻭﯼ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﻮﺩ ﺍﺳﺖ‪.‬‬

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‫ﺩﺭ ﻓﺎﻳﻞ ﻣﺘﻨﯽ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺑﺪﻧﺒﺎﻝ ﺧﻄﻮﻃﯽ ﺑﺎﺷﺪ ﮐﻪ ﺑﺎ ﻋﻨﻮﺍﻥ "ﺍﺯ" ﻭﺟﻮﺩ ﺩﺍﺭﻧﺪ‪.‬‬

‫ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻗﺎﺩﺭ ﺑﻪ ﻧﻤﺎﻳﺶ ﻟﻴﺴﺖ ﺗﻤﺎﻡ ﭘﻴﺎﻡ ﻫﺎ ﺑﺮ ﺍﺳﺎﺱ ﻋﻨﺎﻭﻳﻦ ﻣﺮﺑﻮﻃﻪ‬ ‫ﺍﺳﺖ‪.‬‬

‫ﻣﺜﺎﻝ ﻓﻮﻕ ﺻﺮﻓﺎ" ﻳﮏ ﺳﻴﺴﺘﻢ ﺑﺴﻴﺎﺭ ﺳﺎﺩﻩ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺭﺍ ﻧﺸﺎﻥ‬

‫ﻣﯽ ﺩﺍﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﯽ ﻳﮏ ﺳﻴﺴﺘﻢ ﻭﺍﻗﻌﯽ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫ﺳﻴﺴﺘﻢ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭﺍﻗﻌﯽ‬

‫ﺳﻴﺴﺘﻢ ﻭﺍﻗﻌﯽ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺩﺍﺭﺍﯼ ﺩﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﺘﻔﺎﻭﺕ ﺑﻮﺩﻩ ﮐﻪ ﺑﺮ ﺭﻭﯼ ﻳﮏ‬

‫ﻣﺎﺷﻴﻦ ﺍﺟﺮﺍﺀ ﻣﯽ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻳﮑﯽ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪Simple Mail Transfer(SMTP‬‬

‫‪ (Protocol‬ﺑﻮﺩﻩ ﻭ ﻣﺴﺘﻮﻟﻴﺖ ﭘﻴﺎﻡ ﻫﺎﯼ ﺍﺭﺳﺎﻟﯽ ) ﺧﺮﻭﺝ ( ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﺭﺍ‬ ‫ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﻭﻡ‪ ( Post office Protocol (POP3 ،‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ‬

‫ﻣﺴﺪﻭﻟﻴﺖ ﭘﻴﺎﻡ ﻫﺎﯼ ﺩﺭﻳﺎﻓﺘﯽ ) ﻭﺭﻭﺩ ( ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﺟﺎﻳﮕﺎﻩ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺭﺍ ﻧﺸﺎﻥ ﻣﯽ ﺩﻫﺪ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺑﻪ ﭘﻮﺭﺕ ‪ ٢٥‬ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ POP3‬ﺑﻪ ﭘﻮﺭﺕ ‪ ١١٠‬ﮔﻮﺵ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪SMTP‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﺍﺯ ﻃﺮﻳﻖ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺧﻮﺩ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺑﺮﻧﺎﻣﻪ‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‪ ،‬ﺍﺭﺗﺒﺎﻁ‬

‫ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻣﻮﺟﻮﺩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺎ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‬

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‫‪ SMTP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ) ﺗﻮﺯﻳﻊ ( ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻧﻤﺎﻳﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ‬

‫ﻋﻤﻠﮑﺮﺩ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ ﺭﺍ ﻧﺸﺎﻥ ﻣﯽ ﺩﻫﺪ‪.‬‬

‫ﮐﺎﺭﺑﺮﺍﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺗﻮﺳﻂ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﻣﯽ ﺑﺎﻳﺴﺖ‬

‫ﺗﻨﻈﻴﻤﺎﺕ ﻻﺯﻡ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﺁﺩﺭﺱ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺷﻤﺎ‬ ‫‪ [email protected]‬ﺑﺎﺷﺪ‪ ،‬ﺩﺭ ﺯﻣﺎﻥ ﺗﻨﻈﻴﻢ ﭘﺎﺭﺍﻣﺘﺮﻫﺎﯼ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ )ﺑﻌﻨﻮﺍﻥ‬ ‫ﻣﺜﺎﻝ‪ ،(Outlook :‬ﻧﺎﻡ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻣﯽ ﺑﺎﻳﺴﺖ ﻣﺸﺨﺺ ﮔﺮﺩﺩ‬

‫) ﻓﺮﺽ ﮐﻨﻴﺪ ﻧﺎﻡ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ mail.test.com‬ﺑﺎﺷﺪ(‪ .‬ﭘﺲ ﺍﺯ‬

‫ﺁﻣﺎﺩﻩ ﻧﻤﻮﺩﻥ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﻓﺸﺮﺩﻥ ﺩﮐﻤﻪ "ﺍﺭﺳﺎﻝ"‪ ،‬ﻋﻤﻠﻴﺎﺕ ﺯﻳﺮ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪:‬‬ ‫•‬

‫ﺑﺮﻧﺎﻣﻪ ‪ ،Outlook express‬ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻣﻮﺟﻮﺩ ﺩﺭ‬

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‫ﺑﺮﻧﺎﻣﻪ ‪ Outlook Express‬ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻣﮑﺎﻟﻤﻪ ﺍﯼ ﺭﺍ ﺑﺮﻗﺮﺍﺭﻭ ﺑﻪ‬

‫‪ com.١mail.test‬ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ‪ ، ٢٥‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، SMTP‬ﺁﺩﺭﺱ ﻫﺎﯼ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﻭ ﻣﺤﺘﻮﻳﺎﺕ ﭘﻴﺎﻡ ﺭﺍ ﺍﻋﻼﻥ‬ ‫ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺁﺩﺭﺱ ﮔﻴﺮﻧﺪﻩ ) ﺑﻌﻨﻮﺍﻥ ﻣﺜﺎﻝ ‪ ( [email protected]‬ﺭﺍ‬ ‫ﺑﻪ ﺩﻭ ﺑﺨﺶ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪:‬‬ ‫‪ -‬ﻧﺎﻡ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ )‪(Reza‬‬

‫‪ -‬ﻧﺎﻡ ﺣﻮﺯﻩ )‪(test1.com‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﺩﺍﺭﺍﯼ ﺻﻨﺪﻭﻕ ﭘﺴﺘﯽ ﺑﺮ ﺭﻭﯼ ﻫﻤﺎﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

‫ﺑﺎﺷﺪ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﭘﻴﺎﻡ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺭﺍ ﺑﺴﺎﺩﮔﯽ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ‪ POP3‬ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺍﯼ ﺑﺎ ﻧﺎﻡ " ‪Delivery‬‬

‫‪ ) "agent‬ﺁﮊﺍﻧﺲ ﺗﻮﺯﻳﻊ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﺑﺮ ﺭﻭﯼ‬

‫ﺣﻮﺯﻩ ﺍﯼ ﺩﻳﮕﺮ ﺑﺎﺷﺪ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻧﻴﺎﺯﻣﻨﺪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺣﻮﺯﻩ‬

‫ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ ‪.‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، SMTP‬ﺑﺎ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺍﺭﺗﺒﺎﻁ ﻭ ﺍﺯ ﺍﻭ ﻣﯽ ﺧﻮﺍﻫﺪ ﮐﻪ ﺁﺩﺭﺱ‬ ‫‪ aIP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺣﻮﺯﻩ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺑﻪ ﺍﻃﻼﻉ ﻭﯼ ﺑﺮﺳـﺎﻧﺪ‪.‬‬ ‫) ﻓﺮﺽ ﺍﻳﻦ ﺍﺳﺖ ﮐﻪ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﺩﺍﺭﺍﯼ ﺻﻨﺪﻭﻕ ﭘﺴﺘﯽ ﺑﺮ ﺭﻭﯼ ﻫﻤﺎﻥ ﮐﺎﻣﭙــﻴﻮﺗﺮ‬

‫ﻓﺮﺳﺘـﺪﻩ ﻧﻴـﺴﺖ (‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ‪ ، DNS‬ﺁﺩﺭﺱ ) ﻭ ﻳﺎ ﺁﺩﺭﺱ ﻫﺎﯼ ( ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ) ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ( ‪ SMTP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺣﻮﺯﻩ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺍﻋﻼﻡ‬

‫ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ‪ Test1.com‬ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺣﻮﺯﻩ ‪ Test2.com‬ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ‪ ، ٢٥‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ‬

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‫ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ‪ ، Test2.com‬ﭘﻴﺎﻡ ﺍﺭﺳﺎﻟﯽ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺁﻥ ﺭﺍ‬

‫ﺩﺭ ﺻﻨﺪﻭﻕ ﭘﺴﺘﯽ ﻣﺮﺑﻮﻁ ﺑﻪ ﮔﻴﺮﻧﺪﻩ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ‪ Test1.com‬ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﯼ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ‪ Test2.com‬ﻧﮕﺮﺩﺩ ‪ ،‬ﭘﻴﺎﻡ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ‬ ‫ﻣﺤﻠﯽ ﺧﺎﺹ ﺩﺭ ﻧﻮﺑﺖ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ‪ .‬ﺳﺮﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺩﺭ ﺍﮐﺜﺮ ﻣﺎﺷﻴﻦ ﻫﺎ ﺍﺯ ﺑﺮﻧﺎﻣﻪ‬

‫ﺍﯼ ﺑﺎ ﻧﺎﻡ ‪ Sendmail‬ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﻭﺍﻗﻌﯽ ﻳﮏ ﭘﻴﺎﻡ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩﻩ ﻭ ﺑﺮﺍﯼ ﭘﻴﺎﻡ‬ ‫ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ ﺻﻒ‪ ،‬ﺍﺯ ﺻﻔﯽ ﺑﺎ ﻧﺎﻡ ‪ sendmail queue‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﺑﺮﻧﺎﻣﻪ‬

‫‪ Sendmail‬ﺑﺼﻮﺭﺕ ﺍﺩﻭﺍﺭﯼ) ﺗﮑﺮﺍﺭﯼ( ﺳﻌﯽ ﺩﺭ ﺍﺭﺳﺎﻝ ﻣﺠﺪﺩ ﭘﻴﺎﻡ ﻫﺎﯼ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺻﻒ ﻣﯽ ﻧﻤﺎﻳﺪ ‪ .‬ﻣﺜﻼ" ﻣﻤﮑﻦ ﺍﺳﺖ ﻫﺮ ‪ ١٥‬ﺩﻗﻴﻘﻪ ﻳﮑﺒﺎﺭ ﺗﻼﺵ ﻣﺠﺪﺩ ﺧﻮﺩ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﺭﺍ‬ ‫ﺍﻧﺠﺎﻡ ﺩﻫﺪ‪ .‬ﭘﺲ ﺍﺯ ﮔﺬﺷﺖ ﭼﻬﺎﺭ ﺳﺎﻋﺖ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ﻧﺎﻣﻪ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ‪ ،‬ﭘﻴﺎﻣﯽ ﻣﺒﻨﯽ‬

‫ﺑﺮ ﻭﺟﻮﺩ ﺍﺷﮑﺎﻝ ﺩﺭ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ‪ ،‬ﻓﺮﺳﺘﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﭘﻨﺞ ﺭﻭﺯ‪ ،‬ﺍﮐﺜﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﯼ‬ ‫ﭘﻴﮑﺮﺑﻨﺪﯼ ‪ Sendmail‬ﭘﻴﺎﻣﯽ ﻣﺒﻨﯽ ﺑﺮ ﻋﺪﻡ ﻣﻮﻓﻘﻴﺖ ﺩﺭ ﺗﻮﺯﻳﻊ ﭘﻴﺎﻡ ﺭﺍ ﺑﺮﺍﯼ ﺍﺭﺳﺎﻝ‬

‫ﻣﯽ ﺩﺍﺭﻧﺪ‪.‬‬

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‫ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﯽ ﺑﻴﻦ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺑﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺯﺑﺎﻥ ﺳﺎﺩﻩ ﻣﺘﻨﯽ ﻭ ﺧﻮﺍﻧﺎ‪ ،‬ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺮﻧﺎﻣﻪ‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺧﻮﺩ ﺭﺍ ﻣﻌﺮﻓﯽ ‪ ،‬ﺁﺩﺭﺱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﻭ ﻣﺤﺘﻮﻳﺎﺕ ﭘﻴﺎﻡ ﺭﺍ ﻣﺸﺨﺺ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ) .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ‪ telnet‬ﻣﯽ ﺗﻮﺍﻥ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ‬

‫ﻭ ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ‪ ٢٥‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﮐﺮﺩ(‪.‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ SMTP‬ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ﺳﺎﺩﻩ ﺍﯼ‬ ‫ﻧﻈﻴﺮ ‪ HELLO,MAIL,RCPT,DATA‬ﻭ ‪ ...‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫‪ .HELLO‬ﻣﻌﺮﻓﯽ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‬

‫•‬

‫‪ . EHLO‬ﻣﻌﺮﻓﯽ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺩﺭﺧﻮﺍﺳﺖ ﺣﺎﻟﺖ ﺗﻮﺳﻪ ﻳﺎﻓﺘﻪ‬

‫•‬

‫‪ .MAIL FROM‬ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﻓﺮﺳﺘﻨﺪﻩ‬

‫•‬

‫‪ . RCPT TO‬ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﮔﻴﺮﻧﺪﻩ‬

‫•‬

‫‪ . DATA‬ﻣﺤﺘﻮﻳﺎﺕ ﭘﻴﺎﻡ ﺭﺍ ﻣﺸﺨﺺ ﻣﯽ ﮐﻨﺪ‪.‬‬

‫•‬

‫‪ . RESET‬ﺑﺮﺍﯼ ‪ Reset‬ﻧﻤﻮﺩﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪.‬‬

‫•‬

‫‪ . QUIT‬ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﻗﻄﻊ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫•‬

‫‪ . HELP‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺩﺳﺘﻮﺭﺍﺕ ﺗﻮﺿﻴﺤﺎﺕ ﻻﺯﻡ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪POP3‬‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ‪ ،‬ﺻﻨﺪﻭﻕ ﭘﺴﺘﯽ ﺧﻮﺩ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ‬

‫ﻧﺎﻣﻪ ﻫﺎﯼ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﯽ ﺑﺮﺭﺳﯽ ﻣﯽ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ POP3‬ﺍﺯ ﻃﺮﻳﻖ‬ ‫ﭘﻮﺭﺕ ‪ ١١٠‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﯽ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ POP3‬ﺑﻪ ﻳﮏ ﻧﺎﻡ ‪ Account‬ﻭ‬ ‫ﺭﻣﺰ ﻋﺒﻮﺭ ﻧﻴﺎﺯ ﺩﺍﺭﺩ‪ .‬ﭘﺲ ﺍﺯ ﺗﺎﻳﻴﺪ ﺍﻋﺘﺒﺎﺭ ﻭ ﻣﺠﻮﺯ ﺷﻤﺎ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ POP3‬ﻓﺎﻳﻞ ﻫﺎﯼ‬

‫ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻓﻌﺎﻝ ﻭ ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺁﻧﺎﻥ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺭﺍﺩﻳﻮ ﺍﻳﻨﺘﺮﻧﺘﯽ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﻋﺮﺻﻪ ﭘﺨﺶ ﺻﻮﺕ ) ﺻﺪﺍ ( ﻭ ﺗﺼﻮﻳﺮ‪ ،‬ﻧﻴﺰ ﺗﺤﻮﻻﺕ ﭼﺸﻤﮕﻴﺮﯼ ﺭﺍ‬

‫ﺑﻮﺟﻮﺩ ﺁﻭﺭﺩﻩ ﺍﺳﺖ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﺗﺤﻮﻝ ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﺭﺍﺩﻳﻮ ﺍﺯ ﺳﺎﻝ ‪ ١٩٢٠‬ﺍﺳﺖ‪ .‬ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺍﺯ ﺍﻭﺍﺧﺮ ﺳﺎﻝ ‪ ١٩٩٠‬ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﺟﺪﯼ‬ ‫ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺍﻧﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﺍﺩﻳﻮﻫـﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﻣﯽ ﺗﻮﺍﻥ ﺍﺯ ﻫﺮ ﻣﺤﻞ ﻭ ﺗﻮﺳﻂ ﺻﺮﻓﺎ" ﻳـﮏ‬ ‫ﺩﺳﺘﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻨﺘﺸﺮ ﺷﺪﻩ‪ ،‬ﺩﺳﺘﻴﺎﺑﯽ ﭘﻴﺪﺍ ﮐﺮﺩ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﺍﺩﻳﻮ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺸﺮ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺍﺯ ﺍﻭﺍﻳﻞ ﺳﺎﻝ ‪ ١٩٢٠‬ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺳﺎﻝ‬ ‫‪ ١٩٥٤‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﺑﺪﺍﻉ ﺗﺮﺍﺗﺰﻳﺴﺘﻮﺭ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﺍﺩﻳﻮ ﺑﺸﺪﺕ ﺭﺷﺪ ﻭ ﻣﺘﺪﺍﻭﻝ ﮔﺮﺩﻳﺪ‪.‬‬

‫ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺩﺭ ﺍﻭﺍﺧﺮ ﻗﺮﻥ ﺑﻴﺴﺘﻢ ﻭ ﺍﻭﺍﻳﻞ ﻗﺮﻥ ﺑﻴﺴﺖ ﻭ ﻳﮑﻢ ﻣﻄﺮﺡ ﻭ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫ﺯﻳﺮﺳﺎﺧﺖ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺴﺮﻋﺖ ﺑﺎ ﺍﺳﺘﻘﺒﺎﻝ ﻣﻮﺍﺟﻪ ﮔﺮﺩﻳﺪﻧﺪ‪ .‬ﺑﺮﺍﯼ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺭﺍﺩﻳﻮﻫﺎﯼ‬ ‫ﺍﻳﻨﺘﺮﻧﺘﯽ ﺑﻪ ﻳﮑﺪﺳﺘﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺨﺼﯽ ﻭ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻴﺎﺯ ﺍﺳﺖ‪ .‬ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺑﺼﻮﺭﺕ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺭﺍ ﺩﺭ ﺍﺗﻮﻣﺒﻴﻞ‪ PDA ،‬ﻭ ﺗﻠﻔﻦ‬ ‫ﻫﺎﯼ ﺳﻠﻮﻟﯽ ﻓﺮﺍﻫﻢ ﮐﺮﺩﻩ ﺍﺳﺖ‪ .‬ﻧﺴﻞ ﺟﺪﻳﺪ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﺩﺍﺭﺍﯼ ﻗﺎﺑﻠﻴﺖ ﻫﺎﯼ‬ ‫ﮔﺴﺘﺮﺩﻩ ﺍﯼ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﻣﺰﺍﻳﺎﯼ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ‬

‫ﺍﻳﺴﺘﮕﺎﻫﻬﺎﯼ ﺭﺍﺩﻳﻮﺋﯽ ﺳﻨﺘﯽ‪ ،‬ﺩﺍﺭﺍﯼ ﺩﻭ ﻣﺤﺪﻭﺩﻳﺖ ﻋﻤﺪﻩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺸﺮ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﯽ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬ ‫•‬

‫ﻗﺪﺭﺕ ﺍﻳﺴﺘﮕﺎﻩ ﻓﺮﺳﺘﻨﺪﻩ ) ﻣﻌﻤﻮﻻ" ﻳﮑﺼﺪ ‪(miles‬‬

‫ﺍﻣﻮﺍﺝ ﺭﺍﺩﻳﻮﺋﯽ ﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ) ﺻﺪﻫﺎ ﺍﻳﺴﺘﮕﺎﻩ ﻣﺤﻠﯽ ﻣﻤﮑﻦ ﺍﺳﺖ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‬

‫ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺩﺍﺭﺍﯼ ﻣﺤﺪﻭﺩﻳﺖ ﺟﻐﺮﺍﻓﻴﺎﺋﯽ ﻧﻤﯽ ﺑﺎﺷﻨﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺍﻧﺘﺸﺎﺭ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺗﻮﺳﻂ ﻳﮏ ﺭﺍﺩﻳﻮﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺩﺭ ﺷﺮﻕ‪ ،‬ﻗﺎﺑﻞ ﺷﻨﻴﺪﻥ ﺩﺭ ﻏﺮﺏ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

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‫ﭘﺘﺎﻧﺴﻴﻞ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺑﺴﻴﺎﺭ ﮔﺴﺘﺮﺩﻩ ﺍﺳﺖ‪ .‬ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺭﺍﺩﻳﻮﻫﺎﯼ‬ ‫ﺳﻨﺘﯽ ﮐﻪ ﺻﺮﻓﺎ" ﺍﺯ ﺻﻮﺕ ﺑﺮﺍﯼ ﭘﺨﺶ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺗﺼﺎﻭﻳﺮ‪ ،‬ﮔﺮﺍﻓﻴﮏ‪ ،‬ﻣﺘﻦ‪ ،‬ﻟﻴﻨﮏ ﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﻭ ﺍﺭﺗﺒﺎﻁ ﻣﺘﻘﺎﺑﻞ ﺑﺎ ﺷﻨﻮﻧﺪﻩ ﺭﺍ ﻧﻴﺰ ﺍﺭﺍﺋﻪ‬

‫ﻣﯽ ﺩﻫﻨﺪ‪.‬‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ ﻋﻤﻠﮑﺮﺩ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﺩﺭ ﻣﻮﺍﺭﺩ ﻣﺘﻌﺪﺩﯼ‬ ‫ﺗﻮﺻﻴﻪ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ" ﺩﺭ ﻳﮏ ﺳﻴﺴﺘﻢ ﺁﻣﻮﺯﺷﯽ ﻭ ﻳﺎ ﺁﻣﻮﺯﺵ ﻫﺎﯼ ﻣﺒﺘﻨﯽ ﺑﺮ ﻭﺏ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺍﺯ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺸﺮ ﺍﻃﻼﻋﺎﺕ ﺑﺴﻴﺎﺭ ﺣﺎﺋﺰ ﺍﻫﻤﻴﺖ ﺍﺳﺖ‪ .‬ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ‬

‫ﺍﺯ ﻃﻴﻒ ﮔﺴﺘﺮﺩﻩ ﺍﯼ ﺍﺯ ﺍﻣﻮﺍﺝ ﺑﺮﺍﯼ ﻧﺸﺮ ﺍﻃﻼﻋﺎﺕ ﺧﺼﻮﺻﺎ" ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﻮﺯﻳﮏ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺍﻳﺠﺎﺩ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺭﺍﺩﻳﻮ ﺍﻳﻨﺘﺮﻧﺘﯽ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺭﺍﺩﻳﻮﺋﯽ ﺍﻳﻨﺘﺮﻧﺘﯽ ﺑﻪ ﺍﻣﮑﺎﻧﺎﺕ ﺯﻳﺮ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪:‬‬ ‫•‬ ‫•‬

‫‪CD player‬‬ ‫ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻫﺎﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﮑﺜﻴﺮ ﻳﮏ ‪ Track‬ﻣﻮﺯﻳﮏ ﺍﺯ ﻳﮏ ‪ CD‬ﺑﻪ ﻫﺎﺭﺩ ﺩﻳﺴﮏ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ‬

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‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻭﻳﺮﺍﻳﺶ ﻭ ﺿﺒﻂ ﺻﺪﺍ‬

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‫ﻣﻴﮑﺮﻭﻓﻦ‬

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‫‪ Mixer‬ﻫﺎﯼ ﺻﻮﺗﯽ‬

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‫‪Compressor ، Equalizer‬‬

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‫ﮐﺎﺭﺕ ﺻﺪﺍ‬

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‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺧﺘﺼﺎﺻﯽ ﺑﻬﻤﺮﺍﻩ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻫﺎﯼ ‪encoder‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪Streaming media‬‬

‫ﺑﺮﺍﯼ ﻧﺸﺮ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻳﻖ ﺭﺍﺩﻳﻮﻫﺎﯼ ﺍﻳﻨﺘﺮﻧﺘﯽ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺩﻧﺒﺎﻝ ﻣﯽ ﮔﺮﺩﺩ‪:‬‬

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‫ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﮐﺎﺭﺕ ﺻﺪﺍ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﻭﺍﺭﺩ ﻣﯽ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻳﺴﺘﻢ ﻓﻮﻕ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ ﺩﺭﻳﺎﻓﺘﯽ ﺭﺍ ﺑﻪ ﻓﺮﻣﺖ‬

‫‪Streaming‬‬

‫ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺍﻃﻼﻋﺎ ﺕ ﺻﻮﺗﯽ ﺩﺭﻳﺎﻓﺘﯽ‪ ،‬ﻧﻤﻮﻧﻪ ﺳﺎﺯﯼ ﻭ ﭘﺲ ﺍﺯ ﻗﺸﺮﺩﻩ ﺳﺎﺯﯼ ﺁﻣﺎﺩﻩ ﺍﺭﺳﺎﻝ ﺑﺮ‬ ‫ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬

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‫ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ ﻓﺸﺮﺩﻩ ﺷﺪﻩ‪ ،‬ﺑﺮﺍﯼ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺭﺳﺎﻝ ﻣﯽ ﮔﺮﺩﻧﺪ‪ .‬ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﻣﯽ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﯼ ﻳﮏ ﭘﻬﻨﺎﯼ ﺑﺎﻧﺪ ﺑﺎﻻ ﺑﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎﺷﺪ‪.‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﮐﺮﺩﻩ ﻭ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﺷﻨﻮﻧﺪﻩ ﮐﻪ ﺩﺍﺭﺍﯼ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ‪ Player‬ﻭ ﻳﺎ ‪ Plug-in‬ﻣﯽ ﺑﺎﺷﻨﺪ‪،‬‬

‫ﻗﺎﺩﺭ ﺑﻪ ﺷﻨﻴﺪﻥ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻓﻮﻕ‪ ،‬ﺍﻃﻼﻋﺎ ﺕ ﺻﻮﺗﯽ ‪stream‬‬ ‫ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺭﺍ ﺑﻪ ﺻﻮﺗﯽ ﮐﻪ ﻗﺎﺑﻞ ﺷﻨﻴﺪﻥ ﺗﻮﺳﻂ ﺷﻨﻮﻧﺪﻩ ﺑﺎﺷﻨﺪ‪،‬‬

‫ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ ﺑﺮﺍﯼ ﻋﺮﺿﻪ ﺻﻮﺕ ﺑﺮ ﺭﻭﯼ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ‪:‬‬ ‫‪ Download‬ﻭ ‪ . Streaming media‬ﺩﺭ ﺭﻭﺵ ‪ ، download‬ﻳﮏ ﻓﺎﻳﻞ ﺻﻮﺗﯽ‬ ‫ﺑﺮ ﺭﻭﯼ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﺎﺭﺑﺮ ﺫﺧﻴﺮﻩ ﻣﯽ ﮔﺮﺩﺩ‪ .‬ﻓﺮﻣﺖ ﻫﺎﯼ ﻓﺸﺮﺩﻩ ﻧﻈﻴﺮ ‪ ،mp3‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ‬

‫ﻓﺮﻣﺖ ﻓﺎﻳﻞ ﻫﺎﯼ ﺻﻮﺗﯽ ﺑﺮﺍﯼ ‪ Download‬ﮐﺮﺩﻥ ﻣﯽ ﺑﺎﺷﻨﺪ‪ ) .‬ﺍﺭﺳﺎﻝ ﻫﺮ ﻧﻮﻉ ﻓﺎﻳﻞ‬ ‫ﺻﻮﺗﯽ ﺗﻮﺳﻂ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎ ﻭ ﻳﺎ ﺳﺎﻳﺖ ﻫﺎﯼ ‪ Ftp‬ﺍﻣﮑﺎﻥ ﭘﺬﻳﺮ ﺍﺳﺖ(‪.‬‬ ‫ﺩﺭ ﺭﻭﺵ ‪ ، Streaming‬ﻓﺎﻳﻞ ﺻﻮﺗﯽ ﺫﺧﻴﺮﻩ ﻧﻤﯽ ﮔﺮﺩﺩ ﺑﻠﮑﻪ ﺻﺮﻓﺎ" ﭘﺠﺶ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺍﻧﺘﺸﺎﺭ ﺍﻃﻼﻋﺎﺕ ﺑﮑﻤﮏ ﺭﻭﺵ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﻭ ﺑﺎ ﺑﻬﺮﻩ ﮔﻴﺮﯼ ﺍﺯ ﺳﻪ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺍﻧﺠﺎﻡ‬ ‫ﻣﯽ ﮔﻴﺮﺩ ‪ Encode :‬ﻭ ‪ Server‬ﻭ ‪ . Player‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ encoder‬ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ‬ ‫ﺭﺍ ﺑﻪ ﻓﺮﻣﺖ ‪ streaming‬ﺗﺒﺪﻳﻞ ﻣﯽ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪،‬ﺍﻃﻼﻋﺎﺕ ﺗﺒﺪﻳﻞ ﺷﺪﻩ ﺭﺍ ﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ﺑﺮ ﺭﻭﺱ ﺍﻳﻨﺘﺮﻧﺖ ﻧﻤﻮﺩﻩ ﻭ ﻧﺮﻡ‬

‫ﺍﻓﺰﺍﺭ ‪ ، player‬ﻣﺴﺪﻭﻝ ﺑﺎﺯﻳﺎﺑﯽ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪ .‬ﺩﺭ ﭘﺤﺶ ﻣﺴﺘﻘﻴﻢ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﯼ‬ ‫‪ encoder‬ﻭ ‪ Streamer‬ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﻓﻌﺎﻟﻴﺖ ﻣﯽ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻃﻼﻋﺎﺕ ﺻﻮﺗﯽ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﮐﺎﺭﺕ ﺻﺪﺍ ﺑﻪ ﺳﻴﺴﺘﻢ ﻣﺮﺑﻮﻃﻪ ﺗﻐﺬﻳﻪ ﻭ ﭘﺲ ﺍﺯ ‪ Encode‬ﻧﻤﻮﺩﻥ ﺁﻧﻬﺎ ﺗﻮﺳﻂ ﻧﺮﻡ‬ ‫‪111‬‬

‫ﺍﻓﺰﺍﺭ ﻣﺮﺑﻮﻃﻪ ﺑﺮ ﺭﻭﯼ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ streaming‬ﻗﺮﺍﺭ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪ .‬ﺑﺎﺗﻮﺟﻪ ﺑﻪ‬

‫ﺣﺠﻢ ﺑﺎﻻﯼ ﻋﻤﻠﻴﺎﺕ ﻣﺤﺎﺳﺒﺎﺗﯽ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ Streaming‬ﻣﯽ ﺑﺎﻳﺴﺖ ﻳﮏ ﺳﺮﻭﻳﺲ‬

‫ﺩﻫﻨﺪﻩ ﻗﺪﺭﺗﻤﻨﺪ ﻭ ﺍﺧﺘﺼﺎﺻﯽ ﺑﺎﺷﺪ‪.‬‬

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113

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‬ ‫ﻳﮏ ﺷﺒﮑﻪ ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎ )ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﭼﺎﭘﮕﺮﻭ‪ (...‬ﺑﻮﺩﻩ ﮐﻪ ﺑﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺭﻭﺵ ﺍﺭﺗﺒﺎﻃﻲ )ﮐﺎﺑﻞ‪ ،‬ﺍﻣﻮﺍﺝ ﺭﺍﺩﻳﻮﺋﻲ‪ ،‬ﻣﺎﻫﻮﺍﺭﻩ( ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﺘﺮﺍﮎ ﻣﻨﺎﺑﻊ‬ ‫ﻓﻴﺰﻳﮑﻲ )ﭼﺎﭘﮕﺮ( ﻭ ﺍﺷﺘﺮﺍﮎ ﻣﻨﺎﺑﻊ ﻣﻨﻄﻘﻲ )ﻓﺎﻳﻞ( ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺷﺒﮑﻪ ﻫﺎ‬ ‫ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻧﻴﺰ ﻣﺮﺗﺒﻂ ﺷﺪﻩ ﻭ ﺷﺎﻣﻞ ﺯﻳﺮ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﺷﺒﮑﻪ ﻫﺎ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺭﺍ ﺑﺮ ﺍﺳﺎﺱ ﻣﻮﻟﻔﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ‬

‫ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺧﻲ ﺍﺯ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺍﺷﺎﺭﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﺑﺮ ﺍﺳﺎﺱ ﻧﻮﻉ ﻭﻇﺎﻳﻒ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﻭﻇﺎﻳﻒ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﺩﻭﮔﺮﻭﻩ ﻋﻤﺪﻩ‪:‬‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ )‪ (Servers‬ﻭ ﻳﺎ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ )‪ (Clients‬ﺗﻘﺴﻴﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﺩﺭ ﺷﺒﮑﻪ ﮐﻪ ﺑﺮﺍﻱ ﺳﺎﻳﺮﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺳﺮﻭﻳﺲ ﻫﺎ ﻭﺧﺪﻣﺎﺗﻲ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪،‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﺧﺪﻣﺎﺕ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‬

‫ﺗﻮﺳﻂ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﻨﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ‪ ،Client-Server‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺷﺒﮑﻪ ﻧﻤﻲ ﺗﻮﺍﻧﺪ ﻫﻢ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭ‬ ‫ﻫﻢ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ، Peer-To-Peer‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺗﻮﺍﻧﺪ ﻫﻢ ﺑﺼﻮﺭﺕ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﻭ ﻫﻢ ﺑﺼﻮﺭﺕ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻳﮏ ﺷﺒﮑﻪ ‪ LAN‬ﺩﺭ ﺳﺎﺩﻩ ﺗﺮﻳﻦ ﺣﺎﻟﺖ ﺍﺯ ﺍﺟﺰﺍﻱ ﺯﻳﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺨﺼﻲ ‪ .‬ﻳﮏ ﺷﺒﮑﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﺷﺎﻣﻞ ﭼﻨﺪ ﺻﺪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺎﺷﺪ‪ .‬ﺣﺪﺍﻗﻞ‬ ‫ﻳﮑﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﺸﺨﺺ ﮔﺮﺩﺩ‪.‬‬

‫)ﺩﺭﺻﻮﺭﺗﻲ ﮐﻪ ﺷﺒﮑﻪ ﺍﺯ ﻧﻮﻉ ‪ Client-Server‬ﺑﺎﺷﺪ(‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪،‬‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ ﮐﻪ ﻫﺴﺘﻪ ﺍﺳﺎﺳﻲ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺑﺮ ﺭﻭﻱ ﺁﻥ ﻧﺼﺐ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻳﮏ ﻋﺪﺩ ﮐﺎﺭﺕ ﺷﺒﮑﻪ )‪ (NIC‬ﺑﺮﺍﻱ ﻫﺮ ﺩﺳﺘﮕﺎﻩ‪ .‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻧﻈﻴﺮ ﮐﺎﺭﺕ ﻫﺎﺋﻲ‬ ‫ﺍﺳﺖ ﮐﻪ ﺑﺮﺍﻱ ﻣﻮﺩﻡ ﻭ ﺻﺪﺍ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻣﺴﺌﻮﻝ‬

‫ﺩﺭﻳﺎﻓﺖ‪ ،‬ﺍﻧﺘﻘﺎﻝ‪ ،‬ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﻣﻮﻗﺖ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻭﻇﺎﻳﻒ ﻓﻮﻕ ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺍﺭﺍﻱ ﭘﺮﺩﺍﺯﻧﺪﻩ‪ ،‬ﺣﺎﻓﻈﻪ ﻭ ﮔﺬﺭﮔﺎﻩ‬ ‫ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﻫﺴﺘﻨﺪ‪.‬‬

‫ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﺑﺮ ﺍﺳﺎﺱ ﺗﻮﭘﻮﻟﻮﮊﻱ‬ ‫ﺍﻟﮕﻮﻱ ﻫﻨﺪﺳﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺟﻬﺖ ﺍﺗﺼﺎﻝ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‪ ،‬ﺗﻮﭘﻮﻟﻮﮊﻱ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺒﮑﻪ ﻫﺎ‪ ،‬ﻋﺎﻣﻠﻲ ﻣﻬﻢ ﺩﺭ ﺟﻬﺖ ﮐﺸﻒ ﻭ ﺑﺮﻃﺮﻑ‬ ‫ﻧﻤﻮﺩﻥ ﺧﻄﺎﺀ ﺩﺭ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺍﻧﺘﺨﺎﺏ ﻳﮏ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺧﺎﺹ ﻧﻤﻲ ﺗﻮﺍﻧﺪ ﺑﺪﻭﻥ ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﺎ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﺭﻭﺵ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻂ ﻣﻄﺮﺡ ﮔﺮﺩﺩ‪ .‬ﻧﻮﻉ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺍﻧﺘﺨﺎﺑﻲ ﺟﻬﺖ‬

‫ﺍﺗﺼﺎﻝ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻪ ﻳﮑﺪﻳﮕﺮ‪ ،‬ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺮ ﻧﻮﻉ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﺭﻭﺵ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻂ‬

‫ﺗﺎﺛﻴﺮ ﻣﻲ ﮔﺬﺍﺭﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﺎﺛﻴﺮ ﻣﺴﺘﻘﻴﻢ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺍﻧﺘﺨﺎﺑﻲ ﺩﺭ ﻧﻮﻉ ﮐﺎﺑﻞ ﮐﺸﻲ ﻭ ﻫﺰﻳﻨﻪ‬ ‫ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺁﻥ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺩﻗﺖ ﻭ ﺗﺎﻣﻞ ﺑﻪ ﺍﻧﺘﺨﺎﺏ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻳﮏ ﺷﺒﮑﻪ ﻫﻤﺖ‬ ‫‪115‬‬

‫ﮔﻤﺎﺷﺖ‪ .‬ﻋﻮﺍﻣﻞ ﻣﺨﺘﻠﻔﻲ ﺟﻬﺖ ﺍﻧﺘﺨﺎﺏ ﻳﮏ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺑﻬﻴﻨﻪ ﻣﻄﺮﺡ ﻣﻲ ﺷﻮﺩ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﺍﻳﻦ‬ ‫ﻋﻮﺍﻣﻞ ﺑﺸﺮﺡ ﺫﻳﻞ ﺍﺳﺖ‪:‬‬

‫‪ -‬ﻫﺰﻳﻨﻪ ‪ .‬ﻫﺮ ﻧﻮﻉ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﮐﻪ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ‪ LAN‬ﺍﻧﺘﺨﺎﺏ ﮔﺮﺩﺩ‪ ،‬ﺩﺭ ﻧﻬﺎﻳﺖ ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫ﻋﻤﻠﻴﺎﺕ ﻧﺼﺐ ﺷﺒﮑﻪ ﺩﺭ ﻳﮏ ﺳﺎﺧﺘﻤﺎﻥ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﮔﺮﺩﺩ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﻓﺮﺁﻳﻨﺪﻱ ﻃﻮﻻﻧﻲ‬ ‫ﺟﻬﺖ ﻧﺼﺐ ﮐﺎﻧﺎﻝ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﮐﺎﺑﻞ ﻫﺎ ﻭ ﻣﺤﻞ ﻋﺒﻮﺭ ﮐﺎﺑﻞ ﻫﺎ ﺩﺭ ﺳﺎﺧﺘﻤﺎﻥ ﺍﺳﺖ‪ .‬ﺩﺭ‬ ‫ﺣﺎﻟﺖ ﺍﻳﺪﻩ ﺁﻝ ﮐﺎﺑﻞ ﮐﺸﻲ ﻭ ﺍﻳﺠﺎﺩ ﮐﺎﻧﺎﻝ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺒﻞ ﺍﺯ ﺗﺼﺮﻑ ﻭ‬

‫ﺑﮑﺎﺭﮔﻴﺮﻱ ﺳﺎﺧﺘﻤﺎﻥ ﺍﻧﺠﺎﻡ ﮔﺮﻓﺘﻪ ﺑﺎﺷﺪ‪ .‬ﺑﻬﺮﺣﺎﻝ ﻣﻲ ﺑﺎﻳﺴﺖ ﻫﺰﻳﻨﻪ ﻧﺼﺐ ﺷﺒﮑﻪ ﺑﻬﻴﻨﻪ ﮔﺮﺩﺩ‪.‬‬

‫ ﺍﻧﻌﻄﺎﻑ ﭘﺬﻳﺮﻱ ‪ .‬ﻳﮑﻲ ﺍﺯ ﻣﺰﺍﻳﺎﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ،LAN‬ﺗﻮﺍﻧﺎﺋﻲ ﭘﺮﺩﺍﺯﺵ ﺩﺍﺩﻩ ﻫﺎ ﻭ‬‫ﮔﺴﺘﺮﺩﮔﻲ ﻭ ﺗﻮﺯﻳﻊ ﮔﺮﻩ ﻫﺎ ﺩﺭ ﻳﮏ ﻣﺤﻴﻂ ﺍﺳﺖ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺗﻮﺍﻥ ﻣﺤﺎﺳﺒﺎﺗﻲ ﺳﻴﺴﺘﻢ ﻭ‬

‫ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺗﻤﺎﻡ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪ .‬ﺩﺭ ﺍﺩﺍﺭﺍﺕ ﻫﻤﻪ ﭼﻴﺰ‬ ‫ﺗﻐﻴﻴﺮ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪).‬ﻟﻮﺍﺯﻡ ﺍﺩﺍﺭﻱ‪ ،‬ﺍﺗﺎﻗﻬﺎ ﻭ ‪ .(...‬ﺗﻮﭘﻮﻟﻮﮊﻱ ﺍﻧﺘﺨﺎﺑﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺴﺎﺩﮔﻲ ﺍﻣﮑﺎﻥ‬

‫ﺗﻐﻴﻴﺮ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺜﻼ" ﺍﻳﺴﺘﮕﺎﻫﻲ ﺭﺍ ﺍﺯ ﻧﻘﻄﻪ ﺍﻱ ﺑﻪ ﻧﻘﻄﻪ ﺩﻳﮕﺮ‬ ‫ﺍﻧﺘﻘﺎﻝ ﻭ ﻳﺎ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺟﺪﻳﺪ ﺩﺭ ﺷﺒﮑﻪ ﺑﺎﺷﻴﻢ‪.‬‬ ‫ﺳﻪ ﻧﻮﻉ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺭﺍﻳﺞ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫‪BUS‬‬ ‫‪STAR‬‬ ‫‪RING‬‬ ‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪BUS‬‬

‫ﻳﮑﻲ ﺍﺯ ﺭﺍﻳﺠﺘﺮﻳﻦ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻫﺎ ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﺪﻝ‬

‫ﻓﻮﻕ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﺻﻠﻲ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ )ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ( ﺑﻪ ﺁﻥ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻣﺰﺍﻳﺎﻱ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪BUS‬‬ ‫•‬

‫ﮐﻢ ﺑﻮﺩﻥ ﻃﻮﻝ ﮐﺎﺑﻞ ‪ .‬ﺑﺪﻟﻴﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺧﻂ ﺍﻧﺘﻘﺎﻝ ﺟﻬﺖ ﺍﺗﺼﺎﻝ ﺗﻤﺎﻡ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‪ ،‬ﺩﺭ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﺯ ﮐﺎﺑﻞ ﮐﻤﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻣﻮﺿﻮﻉ ﻓﻮﻕ ﺑﺎﻋﺚ‬ ‫ﭘﺎﻳﻴﻦ ﺁﻣﺪﻥ ﻫﺰﻳﻨﻪ ﻧﺼﺐ ﻭ ﺍﻳﺠﺎﺩ ﺗﺴﻬﻴﻼﺕ ﻻﺯﻡ ﺩﺭ ﺟﻬﺖ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ‬ ‫ﺑﻮﺩ‪.‬‬

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‫ﺳﺎﺧﺘﺎﺭ ﺳﺎﺩﻩ ‪ .‬ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ BUS‬ﺩﺍﺭﺍﻱ ﻳﮏ ﺳﺎﺧﺘﺎﺭ ﺳﺎﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‬ ‫ﺻﺮﻓﺎ" ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ﺑﺮﺍﻱ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﺗﻮﺳﻌﻪ ﺁﺳﺎﻥ‪ .‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺟﺪﻳﺪ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺮﺍﺣﺘﻲ ﺩﺭ ﻧﻘﻄﻪ ﺍﻱ ﺍﺯ ﺷﺒﮑﻪ ﺍﺿﺎﻓﻪ‬ ‫ﮐﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺿﺎﻓﻪ ﺷﺪﻥ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﺑﻴﺸﺘﺮ ﺩﺭ ﻳﮏ ﺳﮕﻤﻨﺖ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬

‫ﺗﻘﻮﻳﺖ ﮐﻨﻨﺪﻩ ﻫﺎﺋﻲ ﺑﻪ ﻧﺎﻡ ‪ Repeater‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬ ‫ﻣﻌﺎﻳﺐ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪BUS‬‬ ‫•‬

‫ﻣﺸﮑﻞ ﺑﻮﺩﻥ ﻋﻴﺐ ﻳﺎﺑﻲ ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﺳﺎﺩﮔﻲ ﻣﻮﺟﻮﺩ ﺩﺭ ﺗﻮﻳﻮﻟﻮﮊﻱ ‪ BUS‬ﺍﻣﮑﺎﻥ ﺑﺮﻭﺯ‬

‫ﺍﺷﺘﺒﺎﻩ ﺭﺍ ﮐﺎﻫﺶ ﻣﻲ ﺩﻫﻨﺪ‪ ،‬ﻭﻟﻲ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﮐﺸﻒ ﺁﻥ ﺳﺎﺩﻩ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﮐﻨﺘﺮﻝ ﺷﺒﮑﻪ ﺩﺭ ﻫﺮ ﮔﺮﻩ‬ ‫ﺩﺍﺭﺍﻱ ﻣﺮﮐﺰﻳﺖ ﻧﺒﻮﺩﻩ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﻣﻲ ﺑﺎﻳﺴﺖ ﻧﻘﺎﻁ ﺯﻳﺎﺩﻱ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺗﺸﺨﻴﺺ ﺧﻄﺎﺀ ﺑﺎﺯﺩﻳﺪ ﻭ ﺑﺮﺭﺳﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫•‬

‫ﺍﻳﺰﻭﻟﻪ ﮐﺮﺩﻥ ﺧﻄﺎﺀ ﻣﺸﮑﻞ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻓﻮﻕ‬ ‫ﺩﭼﺎﺭ ﻣﺸﮑﻞ ﮔﺮﺩﺩ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺩﺭ ﻣﺤﻠﻲ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﺍﺳﺖ ﺭﻓﻊ‬

‫ﻋﻴﺐ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩ ﺧﺎﺹ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﮔﺮﻩ ﺭﺍ ﺍﺯ ﺷﺒﮑﻪ ﺟﺪﺍ ﮐﺮﺩ‪ .‬ﺩﺭ ﺣﺎﻟﺘﻴﮑﻪ‬ ‫ﺍﺷﮑﺎﻝ ﺩﺭ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﺎﺷﺪ‪ ،‬ﺗﻤﺎﻡ ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺷﺒﮑﻪ ﺧﺎﺭﺝ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﻣﺎﻫﻴﺖ ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ﻫﺎ ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺑﺮﺍﻱ ﺗﻮﺳﻌﻪ ﺷﺒﮑﻪ ﺍﺯ ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺭ ﺳﺎﺧﺘﺎﺭ ﺷﺒﮑﻪ ﺗﻐﻴﻴﺮﺍﺗﻲ ﻧﻴﺰ ﺩﺍﺩﻩ ﺷﻮﺩ‪ .‬ﻣﻮﺿﻮﻉ ﻓﻮﻕ‬

‫ﻣﺴﺘﻠﺰﻡ ﺑﮑﺎﺭﮔﻴﺮﻱ ﮐﺎﺑﻞ ﺑﻴﺸﺘﺮ ﻭ ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻥ ﺍﺗﺼﺎﻻﺕ ﻣﺨﺼﻮﺹ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬ ‫‪117‬‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪STAR‬‬

‫ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺍﺯ ﻧﺎﻡ ﺁﻥ ﻣﺸﺨﺺ ﺍﺳﺖ‪ ،‬ﺍﺯ ﻣﺪﻟﻲ ﺷﺒﻴﻪ‬ ‫"ﺳﺘﺎﺭﻩ" ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻣﻌﻤﻮﻻ" ﺑﻪ ﻳﮏ‬ ‫ﺩﺳﺘﮕﺎﻩ ﺧﺎﺹ ﺑﺎ ﻧﺎﻡ " ﻫﺎﺏ " ﻣﺘﺼﻞ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬

‫ﻣﺰﺍﻳﺎﻱ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪STAR‬‬ ‫•‬

‫ﺳﺎﺩﮔﻲ ﺳﺮﻭﻳﺲ ﺷﺒﮑﻪ ‪ .‬ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ STAR‬ﺷﺎﻣﻞ ﺗﻌﺪﺍﺩﻱ ﺍﺯ ﻧﻘﺎﻁ ﺍﺗﺼﺎﻟﻲ ﺩﺭ ﻳﮏ‬ ‫ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ﺍﺳﺖ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺗﻐﻴﻴﺮ ﺩﺭ ﺳﺎﺧﺘﺎﺭ ﻭ ﺳﺮﻭﻳﺲ ﺷﺒﮑﻪ ﺭﺍ ﺁﺳﺎﻥ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﻫﺮ ﺍﺗﺼﺎﻝ ﻳﮑﺪﺳﺘﮕﺎﻩ ‪ .‬ﻧﻘﺎﻁ ﺍﺗﺼﺎﻟﻲ ﺩﺭ ﺷﺒﮑﻪ ﺫﺍﺗﺎ" ﻣﺴﺘﻌﺪ ﺍﺷﮑﺎﻝ ﻫﺴﺘﻨﺪ‪ .‬ﺩﺭ‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ STAR‬ﺍﺷﮑﺎﻝ ﺩﺭ ﻳﮏ ﺍﺗﺼﺎﻝ‪ ،‬ﺑﺎﻋﺚ ﺧﺮﻭﺝ ﺁﻥ ﺧﻂ ﺍﺯ ﺷﺒﮑﻪ ﻭ‬ ‫ﺳﺮﻭﻳﺲ ﻭ ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﺧﻂ ﻣﺰﺑﻮﺭ ﺍﺳﺖ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺗﺎﺛﻴﺮﻱ ﺩﺭ ﻋﻤﻠﮑﺮﺩ ﺳﺎﻳﺮ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻧﺨﻮﺍﻫﺪ ﮔﺬﺍﺷﺖ‪.‬‬

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‫ﮐﻨﺘﺮﻝ ﻣﺮﮐﺰﻱ ﻭ ﻋﻴﺐ ﻳﺎﺑﻲ ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﻣﺴﺌﻠﻪ ﮐﻪ ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ‬ ‫ﻫﺮ ﺍﻳﺴﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﺍﺳﺖ‪ ،‬ﺍﺷﮑﺎﻻﺕ ﻭ ﺍﻳﺮﺍﺩﺍﺕ ﺩﺭ ﺷﺒﮑﻪ ﺑﺴﺎﺩﮔﻲ‬

‫ﺗﺸﺨﻴﺺ ﻭ ﻣﻬﺎﺭ ﺧﻮﺍﻫﻨﺪ ﮔﺮﺩﻳﺪ‪.‬‬ ‫•‬

‫ﺭﻭﺵ ﻫﺎﻱ ﺳﺎﺩﻩ ﺩﺳﺘﻴﺎﺑﻲ ‪ .‬ﻫﺮ ﺍﺗﺼﺎﻝ ﺩﺭ ﺷﺒﮑﻪ ﺷﺎﻣﻞ ﻳﮏ ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ﻭ ﻳﮏ ﮔﺮﻩ‬

‫ﺟﺎﻧﺒﻲ ﺍﺳﺖ ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺣﻬﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ‬

‫ﺍﻃﻼﻋﺎﺕ ﺩﺍﺭﺍﻱ ﺍﻟﮕﻮﺭﻳﺘﻤﻲ ﺳﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﻣﻌﺎﻳﺐ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪STAR‬‬ ‫•‬

‫ﺯﻳﺎﺩ ﺑﻮﺩﻥ ﻃﻮﻝ ﮐﺎﺑﻞ ‪ .‬ﺑﺪﻟﻴﻞ ﺍﺗﺼﺎﻝ ﻣﺴﺘﻘﻴﻢ ﻫﺮ ﮔﺮﻩ ﺑﻪ ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ‪ ،‬ﻣﻘﺪﺍﺭ ﺯﻳﺎﺩﻱ‬ ‫ﮐﺎﺑﻞ ﻣﺼﺮﻑ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﻫﺰﻳﻨﻪ ﮐﺎﺑﻞ ﻧﺴﺒﺖ ﺑﻪ ﺗﻤﺎﻡ ﺷﺒﮑﻪ‪،‬ﮐﻢ ﺍﺳﺖ‪،‬‬

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‫ﺗﺮﺍﮐﻢ ﺩﺭ ﮐﺎﻧﺎﻝ ﮐﺸﻲ ﺟﻬﺖ ﮐﺎﺑﻞ ﻫﺎ ﻭ ﻣﺴﺎﺋﻞ ﻣﺮﺑﻮﻁ ﺑﻪ ﻧﺼﺐ ﻭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺁﻧﻬﺎ‬

‫ﺑﻄﻮﺭ ﻗﺎﺑﻞ ﺗﻮﺟﻬﻲ ﻫﺰﻳﻨﻪ ﻫﺎ ﺭﺍ ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﻣﺸﮑﻞ ﺑﻮﺩﻥ ﺗﻮﺳﻌﻪ ‪ .‬ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻥ ﻳﮏ ﮔﺮﻩ ﺟﺪﻳﺪ ﺑﻪ ﺷﺒﮑﻪ ﻣﺴﺘﻠﺰﻡ ﻳﮏ ﺍﺗﺼﺎﻝ ﺍﺯ‬

‫ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ﺑﻪ ﮔﺮﻩ ﺟﺪﻳﺪ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﺩﺭ ﺯﻣﺎﻥ ﮐﺎﺑﻞ ﮐﺸﻲ ﭘﻴﺶ ﺑﻴﻨﻲ ﻫﺎﻱ ﻻﺯﻡ‬ ‫ﺟﻬﺖ ﺗﻮﺳﻌﻪ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻭﻟﻲ ﺩﺭ ﺑﺮﺧﻲ ﺣﺎﻻﺕ ﻧﻈﻴﺮ ﺯﻣﺎﻧﻴﮑﻪ ﻃﻮﻝ‬ ‫ﺯﻳﺎﺩﻱ ﺍﺯ ﮐﺎﺑﻞ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﻮﺩﻩ ﻭ ﻳﺎ ﺍﺗﺼﺎﻝ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮔﺮﻩ ﻫﺎﻱ ﻏﻴﺮ ﻗﺎﺑﻞ ﭘﻴﺶ‬

‫ﺑﻴﻨﻲ ﺍﻭﻟﻴﻪ‪ ،‬ﺗﻮﺳﻌﻪ ﺷﺒﮑﻪ ﺭﺍ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫•‬

‫ﻭﺍﺑﺴﺘﮕﻲ ﺑﻪ ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻧﻘﻄﻪ ﻣﺮﮐﺰﻱ )ﻫﺎﺏ( ﺩﺭ ﺷﺒﮑﻪ ﺑﺎ ﻣﺸﮑﻞ‬ ‫ﻣﻮﺍﺟﻪ ﺷﻮﺩ‪ ،‬ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﻏﻴﺮﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪RING‬‬

‫ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﺼﻮﺭﺕ ﻳﮏ ﺣﻠﻘﻪ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ‬

‫ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ )ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ( ﺑﻪ ﻳﮏ‬ ‫ﮐﺎﺑﻞ ﮐﻪ ﺑﺼﻮﺭﺕ ﻳﮏ ﺩﺍﻳﺮﻩ ﺑﺴﺘﻪ ﺍﺳﺖ‪ ،‬ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻫﺮ ﮔﺮﻩ ﺑﻪ ﺩﻭ ﻭ‬

‫ﻓﻘﻂ ﺩﻭ ﻫﻤﺴﺎﻳﻪ ﻣﺠﺎﻭﺭ ﺧﻮﺩ ﻣﺘﺼﻞ ﺍﺳﺖ‪ .‬ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮔﺮﻩ ﻣﺠﺎﻭﺭ ﺩﺭﻳﺎﻓﺖ ﻭ ﺑﻪ ﮔﺮﻩ ﺑﻌﺪﻱ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺍﺩﻩ ﻫﺎ ﻓﻘﻂ ﺩﺭ ﻳﮏ ﺟﻬﺖ ﺣﺮﮐﺖ ﮐﺮﺩﻩ ﻭ ﺍﺯ ﺍﻳﺴﺘﮕﺎﻫﻲ ﺑﻪ‬ ‫ﺍﻳﺴﺘﮕﺎﻩ ﺩﻳﮕﺮ ﺍﻧﺘﻘﺎﻝ ﭘﻴﺪﺍ ﻣﻲ ﮐﻨﻨﺪ‪.‬‬

‫ﻣﺰﺍﻳﺎﻱ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪RING‬‬ ‫•‬

‫ﮐﻢ ﺑﻮﺩﻥ ﻃﻮﻝ ﮐﺎﺑﻞ ‪ .‬ﻃﻮﻝ ﮐﺎﺑﻠﻲ ﮐﻪ ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ ﺑﮑﺎﺭ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻗﺎﺑﻞ‬

‫ﻣﻘﺎﻳﺴﻪ ﺑﻪ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ BUS‬ﻧﺒﻮﺩﻩ ﻭ ﻃﻮﻝ ﮐﻤﻲ ﺭﺍ ﺩﺭ ﺑﺮﺩﺍﺭﺩ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺑﺎﻋﺚ‬

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‫ﮐﺎﻫﺶ ﺗﻌﺪﺍﺩ ﺍﺗﺼﺎﻻﺕ )ﮐﺎﻧﮑﺘﻮﺭ( ﺩﺭ ﺷﺒﮑﻪ ﺷﺪﻩ ﻭ ﺿﺮﻳﺐ ﺍﻋﺘﻤﺎﺩ ﺑﻪ ﺷﺒﮑﻪ ﺭﺍ‬

‫ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﻧﻴﺎﺯ ﺑﻪ ﻓﻀﺎﺋﻲ ﺧﺎﺹ ﺟﻬﺖ ﺍﻧﺸﻌﺎﺑﺎﺕ ﺩﺭ ﮐﺎﺑﻞ ﮐﺸﻲ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬ﺑﺪﻟﻴﻞ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ﺟﻬﺖ ﺍﺗﺼﺎﻝ ﻫﺮ ﮔﺮﻩ ﺑﻪ ﮔﺮﻩ ﻫﻤﺴﺎﻳﻪ ﺍﺵ‪ ،‬ﺍﺧﺘﺼﺎﺹ ﻣﺤﻞ ﻫﺎﺋﻲ‬ ‫ﺧﺎﺹ ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﺎﺑﻞ ﮐﺸﻲ ﺿﺮﻭﺭﺗﻲ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﻣﻨﺎﺳﺐ ﺟﻬﺖ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﺎﻋﺚ ﺑﺎﻻ ﺭﻓﺘﻦ ﻧﺮﺥ ﺳﺮﻋﺖ‬

‫ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﭼﻮﻥ ﺩﺭ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺗﺮﺍﻓﻴﮏ ﺩﺍﺩﻩ ﻫﺎ ﺩﺭ ﻳﮏ‬ ‫ﺟﻬﺖ ﺍﺳﺖ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ‬

‫ﺗﻤﺎﻳﻞ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﻫﺮ ﺑﺨﺶ ﺍﺯﺷﺒﮑﻪ ﺍﺯ ﻳﮏ ﻧﻮﻉ ﮐﺎﺑﻞ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﻣﺜﻼ" ﺩﺭ ﻣﺤﻴﻂ ﻫﺎﻱ ﺍﺩﺭﺍﻱ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﻣﺴﻲ ﻭ ﺩﺭ ﻣﺤﻴﻂ ﮐﺎﺭﺧﺎﻧﻪ ﺍﺯ‬ ‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬

‫ﻣﻌﺎﻳﺐ ﺗﻮﭘﻮﻟﻮﮊﻱ ‪RING‬‬ ‫•‬

‫ﺍﺷﮑﺎﻝ ﺩﺭ ﻳﮏ ﮔﺮﻩ ﺑﺎﻋﺚ ﺍﺷﮑﺎﻝ ﺩﺭ ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ‬

‫ﺍﺷﮑﺎﻝ ﺩﺭ ﻳﮏ ﮔﺮﻩ‪ ،‬ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﺑﺎ ﺍﺷﮑﺎﻝ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻭ ﺗﺎ ﺯﻣﺎﻧﻴﮑﻪ ﮔﺮﻩ‬ ‫ﻣﻌﻴﻮﺏ ﺍﺯ ﺷﺒـﮑﻪ ﺧﺎﺭﺝ ﻧﮕﺮﺩﺩ‪ ،‬ﻫــﻴﭽﮕﻮﻧﻪ ﺗﺮﺍﻓﻴــــﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺭﻭﻱ ﺷﺒــﮑﻪ‬ ‫ﻧﻤﻲ ﺗﻮﺍﻥ ﺩﺍﺷﺖ‪.‬‬

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‫ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﻣﺸﮑﻞ ﺍﺳﺖ ‪ .‬ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ ﺩﺭ ﻳﮏ ﮔﺮﻩ ﻣﻲ ﺗﻮﺍﻧﺪ ﺭﻭﻱ ﺗﻤﺎﻡ‬ ‫ﮔﺮﻫﻬﺎﻱ ﺩﻳﮕﺮ ﺗﺎﺛﻴﺮ ﮔﺬﺍﺭ ﺑﺎﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻋﻴﺐ ﻳﺎﺑﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﭼﻨﺪﻳﻦ ﮔﺮﻩ‬

‫ﺑﺮﺭﺳﻲ ﺗﺎ ﮔﺮﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﭘﻴﺪﺍ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺗﻐﻴﻴﺮ ﺩﺭﺳﺎﺧﺘﺎﺭﺷﺒﮑﻪ ﻣﺸﮑﻞ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﮔﺴﺘﺮﺵ ﻭ ﻳﺎ ﺍﺻﻼﺡ ﺣﻮﺯﻩ‬

‫ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﺗﺤﺖ ﭘﻮﺷﺶ ﺷﺒﮑﻪ‪ ،‬ﺑﺪﻟﻴﻞ ﻣﺎﻫﻴﺖ ﺣﻠﻘﻮﻱ ﺷﺒﮑﻪ ﻣﺴﺎﺋﻠﻲ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ‬

‫ﺁﻣﺪ‪.‬‬ ‫•‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ﺑﺮ ﺭﻭﻱ ﻧﻮﻉ ﺩﺳﺘﻴﺎﺑﻲ ﺗﺎﺛﻴﺮ ﻣﻲ ﮔﺬﺍﺭﺩ‪ .‬ﻫﺮ ﮔﺮﻩ ﺩﺭ ﺷﺒﮑﻪ ﺩﺍﺭﺍﻱ‬ ‫ﻣﺴﺌﻮﻟﻴﺖ ﻋﺒﻮﺭ ﺩﺍﺩﻥ ﺩﺍﺩﻩ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﮔﺮﻩ ﻣﺠﺎﻭﺭ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺷﺘﻪ ﺍﺳﺖ‪ .‬ﻗﺒﻞ ﺍﺯ‬ ‫‪120‬‬

‫ﺍﻳﻨﮑﻪ ﻳﮏ ﮔﺮﻩ ﺑﺘﻮﺍﻧﺪ ﺩﺍﺩﻩ ﺧﻮﺩ ﺭﺍ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺑﺮﺳﺪ‬ ‫ﮐﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﺍﺳﺖ‪.‬‬

‫ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﺑﺮ ﺍﺳﺎﺱ ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻲ ﺗﺤﺖ ﭘﻮﺷﺶ ‪.‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﺗﺤﺖ ﭘﻮﺷﺶ ﺑﻪ ﺳﻪ ﮔﺮﻭﻩ ﺗﻘﺴﻴﻢ‬

‫ﻣﻲ ﮔﺮﺩﻧﺪ‪:‬‬ ‫•‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ) ﮐﻮﭼﮏ ( ‪LAN‬‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺘﻮﺳﻂ ‪MAN‬‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮔﺴﺘﺮﺩﻩ ‪WAN‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ . LAN‬ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﮐﻪ ﺗﻮﺳﻂ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﭘﻮﺷﺶ ﺩﺍﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ ،‬ﻳﮏ ﻣﺤﻴﻂ ﮐﻮﭼﮏ ﻧﻈﻴﺮ ﻳﮏ ﺳﺎﺧﺘﻤﺎﻥ ﺍﺩﺍﺭﻱ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﺩﺍﺭﺍﻱ‬ ‫ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫ﺗﻮﺍﻧﺎﺋﻲ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ‬

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‫ﻣﺤﺪﻭﺩﻳﺖ ﻓﺎﺻﻠﻪ‬

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‫ﻗﺎﺑﻠﻴﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺍﺭﺯﺍﻥ ﻧﻈﻴﺮ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ‬

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‫ﻧﺮﺥ ﭘﺎﻳﻴﻦ ﺧﻄﺎﺀ ﺩﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺤﺪﻭﺩ ﺑﻮﺩﻥ ﻓﺎﺻﻠﻪ‬

‫ﺍﻃﻼﻋﺎﺕ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ . MAN‬ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﮐﻪ ﺗﻮﺳﻂ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﭘﻮﺷﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪،‬‬ ‫ﺩﺭ ﺣﺪ ﻭ ﺍﻧﺪﺍﺯﻩ ﻳﮏ ﺷﻬﺮ ﻭ ﻳﺎ ﺷﻬﺮﺳﺘﺎﻥ ﺍﺳﺖ‪ .‬ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﺑﺸﺮﺡ‬

‫ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﭘﻴﭽﻴﺪﮔﻲ ﺑﻴﺸﺘﺮ ﻧﺴﺒﺖ ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ‬

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‫ﻗﺎﺑﻠﻴﺖ ﺍﺭﺳﺎﻝ ﺗﺼﺎﻭﻳﺮ ﻭ ﺻﺪﺍ‬

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‫ﻗﺎﺑﻠﻴﺖ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ . WAN‬ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﮐﻪ ﺗﻮﺳﻂ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﭘﻮﺷﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪،‬‬ ‫ﺩﺭ ﺣﺪ ﻭ ﺍﻧﺪﺍﺯﻩ ﮐﺸﻮﺭ ﻭ ﻗﺎﺭﻩ ﺍﺳﺖ‪ .‬ﻭﻳﮋﮔﻲ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺑﺸﺮﺡ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﻗﺎﺑﻠﻴﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﮐﺸﻮﺭﻫﺎ ﻭ ﻗﺎﺭﻩ ﻫﺎ‬

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‫ﻗﺎﺑﻠﻴﺖ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺷﺒﮑﻪ ﻫﺎﻱ ‪LAN‬‬

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‫ﺳﺮﻋﺖ ﭘﺎﻳﻴﻦ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﺴﺒﺖ ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ‪LAN‬‬

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‫ﻧﺮﺥ ﺧﻄﺎﻱ ﺑﺎﻻ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﮔﺴﺘﺮﺩﮔﻲ ﻣﺤﺪﻭﺩﻩ ﺗﺤﺖ ﭘﻮﺷﺶ‬

‫ﮐﺎﺑﻞ ﺩﺭ ﺷﺒﮑﻪ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﺍﺯ ﮐﺎﺑﻞ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯﭼﻨﺪﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺑﺮﺧﻲ‬ ‫ﻣﻮﺍﺭﺩ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺻﺮﻓﺎ" ﺍﺯ ﻳﮏ ﻧﻮﻉ ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﻳﺎ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺷﺮﺍﻳﻂ‬ ‫ﻣﻮﺟﻮﺩ ﺍﺯ ﭼﻨﺪﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ .‬ﻧﻮﻉ ﮐﺎﺑﻞ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺑﺮﺍﻱ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ‬

‫ﻋﻮﺍﻣﻞ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ‪ :‬ﺗﻮﭘﻮﻟﻮﮊﻱ ﺷﺒﮑﻪ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻭ ﺍﻧﺪﺍﺯﻩ ﺷﺒﮑﻪ ﺑﺴﺘﮕﻲ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺁﮔﺎﻫﻲ ﺍﺯ ﺧﺼﺎﻳﺺ ﻭ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎ ﻭ ﺗﺎﺛﻴﺮ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﻬﺎ ﺑﺮ‬ ‫ﺳﺎﻳﺮ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺷﺒﮑﻪ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﻣﻮﻓﻖ ﺑﺴﻴﺎﺭ ﻻﺯﻡ‬

‫ﺍﺳﺖ‪.‬‬

‫ﮐﺎﺑﻞ ‪(UTP( Unshielded Twisted pair‬‬ ‫ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻠﻲ ﮐﻪ ﺩﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﻫﺎ ﺩﺍﺭﺍﻱ ﺩﻭ ﺭﺷﺘﻪ ﺳﻴﻢ ﺑﻪ ﻫﻢ ﭘﻴﭽﻴﺪﻩ ﺑﻮﺩﻩ ﮐﻪ ﻫﺮ ﺩﻭ ﻧﺴﺒﺖ‬ ‫ﺯﻣﻴﻦ ﺩﺍﺭﺍﻱ ﻳﮏ ﺍﻣﭙﺪﺍﻧﺶ ﻳﮑﺴﺎﻥ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ ﺗﺎﺛﻴﺮ ﭘﺬﻳﺮﻱ ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﮐﺎﺑﻞ ﻫﺎ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﺠﺎﻭﺭ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﻣﻨﺎﺑﻊ ﺧﺎﺭﺟﻲ ﮐﺎﻫﺶ ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪ .‬ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ‬

‫ﺗﺎﺑﻴﺪﻩ ﺩﺍﺭﺍﻱ ﺩﻭ ﻣﺪﻝ ﻣﺘﻔﺎﻭﺕ‪) Shielded :‬ﺭﻭﮐﺶ ﺩﺍﺭ( ﻭ ‪) Unshielded‬ﺑﺪﻭﻥ‬ ‫ﺭﻭﮐﺶ( ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﮐﺎﺑﻞ ‪ UTP‬ﻧﺴﺒﺖ ﺑﻪ ﮐﺎﺑﻞ ‪ STP‬ﺑﻤﺮﺍﺗﺐ ﻣﺘﺪﺍﻭﻝ ﺗﺮ ﺑﻮﺩﻩ ﻭ ﺩﺭ ﺍﮐﺜﺮ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫‪122‬‬

‫ﮐﻴﻔﻴﺖ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﻣﺘﻐﻴﺮ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﻌﻤﻮﻟﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺑﺮﺍﻱ ﺗﻠﻔﻦ ﺗﺎ‬

‫ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺭﺍ ﺷﺎﻣﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﮐﺎﺑﻞ ﺩﺍﺭﺍﻱ ﭼﻬﺎﺭ ﺯﻭﺝ ﺳﻴﻢ ﺑﻮﺩﻩ ﻭ ﺩﺭﻭﻥ‬

‫ﻳﮏ ﺭﻭﮐﺶ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﻧﺪ‪ .‬ﻫﺮ ﺯﻭﺝ ﺑﺎ ﺗﻌﺪﺍﺩ ﻣﺸﺨﺼﻲ ﭘﻴﭻ ﺗﺎﺑﺎﻧﺪﻩ ﺷﺪﻩ ) ﺩﺭ ﻭﺍﺣﺪ ﺍﻳﻨﭻ‬ ‫( ﺗﺎ ﺗﺎﺛﻴﺮ ﭘﺬﻳﺮﻱ ﺁﻥ ﺍﺯ ﺳﺎﻳﺮ ﺯﻭﺝ ﻫﺎ ﻭ ﻳﺎﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﮐﺎﻫﺶ ﻳﺎﺑﺪ‪.‬‬

‫ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺩﺍﺭﺍﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺑﻮﺩﻩ ﮐﻪ ﺩﺭ ﮔﺮﻭﻫﻬﺎﻱ )‪(Categories‬‬

‫ﻣﺘﻔﺎﻭﺕ ﺯﻳﺮ ﺗﻘﺴﻴﻢ ﺷﺪﻩ ﺍﻧﺪ‪:‬‬

‫ﮐﺎﺭﺑﺮﺩ‬

‫‪Type‬‬

‫‪ Cat 1‬ﻓﻘﻂ ﺻﻮﺕ ) ﮐﺎﺑﻞ ﻫﺎﻱ ﺗﻠﻔﻦ (‬ ‫‪ Cat 2‬ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ ‪ ٤‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬ ‫‪ Cat 3‬ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ ‪ ١٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬ ‫‪ Cat 4‬ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ ‪ ٢٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬ ‫‪ Cat 5‬ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ ‪ ١٠٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫ﻣﺰﺍﻳﺎﻱ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ‪:‬‬ ‫•‬

‫ﺳﺎﺩﮔﻲ ﻭ ﻧﺼﺐ ﺁﺳﺎﻥ‬

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‫ﺍﻧﻌﻄﺎﻑ ﭘﺬﻳﺮﻱ ﻣﻨﺎﺳﺐ‬

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‫ﺩﺍﺭﺍﻱ ﻭﺯﻥ ﮐﻢ ﺑﻮﺩﻩ ﻭ ﺑﺮﺍﺣﺘﻲ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻣﻌﺎﻳﺐ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ‪:‬‬ ‫•‬

‫ﺗﻀﻌﻴﻒ ﻓﺮﮐﺎﻧﺲ‬

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‫ﺑﺪﻭﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ﻫﺎ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﻞ ﺳﻴﮕﻨﺎﻝ ﺩﺭ ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ‬

‫•‬

‫ﭘﺎﻳﻴﻦ ﺑﻮﺩﻥ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‬

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‫ﺑﺪﻟﻴﻞ ﭘﺬﻳﺮﺵ ﭘﺎﺭﺍﺯﻳﺖ ﺩﺭ ﻣﺤﻴﻂ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﺳﻨﮕﻴﻦ ﺑﺨﺪﻣﺖ ﮔﺮﻓﺘﻪ ﻧﻤﻲ ﺷﻮﻧﺪ‪.‬‬

‫ﻧﻤﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﮐﺎﻧﮑﺘﻮﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺑﺮﺍﻱ ﮐﺎﺑﻞ ﻫﺎﻱ‪ ،UTP‬ﺍﺯ ﻧﻮﻉ ‪ RJ-45‬ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﮐﺎﻧﮑﺘﻮﺭ ﻓﻮﻕ ﺷﺒﺎﻫﺖ‬ ‫ﺯﻳﺎﺩﻱ ﺑﻪ ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ ﺗﻠﻔﻦ )‪ (RJ-11‬ﺩﺍﺭﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻴﻦ ﻫﺎﻱ ﮐﺎﻧﮑﺘﻮﺭ ﻓﻮﻕ‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺪﺭﺳﺘﻲ ﭘﻴﮑﺮﺑﻨﺪﻱ ﮔﺮﺩﻧﺪ‪( Jack Registered:RJ ) .‬‬

‫ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻝ‬ ‫ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻣﺤﻴﻂ ﻫﺎﻱ ﺍﻧﺘﻘﺎﻝ ﺩﺭ ﻣﺨﺎﺑﺮﺍﺕ ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻝ ﻭ ﻳﺎ ﻫﻢ ﻣﺤﻮﺭ‬

‫ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﻫﺎ ﺍﺯ ﺳﺎﻝ ‪ ١٩٣٦‬ﺑﺮﺍﻱ ﺍﻧﺘﻘﺎﻝ ﺍﺧﺒﺎﺭ ﻭ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺩﻧﻴﺎﺭ ﺑﻪ ﮐﺎﺭ‬ ‫ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﻫﺎ‪ ،‬ﺩﻭ ﺳﻴﻢ ﺗﺸﮑﻴﻞ ﺩﻫﻨﺪﻩ ﻳﮏ ﺯﻭﺝ‪ ،‬ﺍﺯ ﺣﺎﻟﺖ ﻣﺘﻘﺎﺭﻥ‬ ‫ﺧﺎﺭﺝ ﺷﺪﻩ ﻭ ﻫﺮ ﺯﻭﺝ ﺍﺯ ﻳﮏ ﺳﻴﻢ ﺩﺭ ﻣﻐﺰ ﻭ ﻳﮏ ﻻﻳﻪ ﻣﺴﻲ ﺑﺎﻓﺘﻪ ﺷﺪﻩ ﺩﺭ ﺍﻃﺮﺍﻑ ﺁﻥ‬

‫ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻧﻮﻉ ﺩﻳﮕﺮ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﻮﺍﮐﺴﻴﺎﻝ‪ ،‬ﺑﻪ ﺣﺎﻱ ﻻﻳﻪ ﻣﺴﻲ ﺑﺎﻓﺘﻪ ﺷﺪﻩ‪ ،‬ﺍﺯ‬ ‫ﺗﻴﻮﭖ ﻣﺴﻲ ﺍﺳﺘﻮﺍﻧﻪ ﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻣﺎﺩﻩ ﺍﻱ ﭘﻼﺳﺘﻴﮑﻲ ﺍﻳﻦ ﺩﻭ ﻫﺎﺩﻱ ﺭﺍ ﺍﺯ ﻳﮑﺪﻳﮕﺮ‬ ‫ﺟﺪﺍ ﻣﻲ ﮐﻨﺪ‪ .‬ﻣﺎﺩﻩ ﭘﻼﺳﺘﻴﮑﻲ ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺼﻮﺭﺕ ﺩﻳﺴﮑﻬﺎﻱ ﭘﻼﺳﺘﻴﮑﻲ ﻳﺎ ﺷﻴﺸﻪ ﺍﻱ ﺩﺭ‬

‫ﻓﻮﺍﺻﻞ ﻣﺨﺘﻠﻒ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﻣﺎﻧﻊ ﺍﺯ ﺗﻤﺎﺱ ﺩﻭ ﻫﺎﺩﻱ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺷﻮﺩ ﻭ ﻳﺎ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﻭ‬ ‫ﻫﺎﺩﻱ ﺩﺭ ﺗﻤﺎﻡ ﻃﻮﻝ ﮐﺎﺑﻞ ﺑﻮﺳﻴﻠﻪ ﻣﻮﺍﺩ ﭘﻼﺳﺘﻴﮑﻲ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﺟﺪﺍ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻣﺰﺍﻳﺎﻱ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﻮﺍﮐﺴﻴﺎﻝ ‪:‬‬

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‫ﻗﺎﺑﻠﻴﺖ ﺍﻋﺘﻤﺎﺩ ﺑﺎﻻ‬

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‫ﻇﺮﻓﻴﺖ ﺑﺎﻻﻱ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﺣﺪﺍﮐﺜﺮ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ‪ ٣٠٠‬ﻣﮕﺎﻫﺮﺗﺰ‬

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‫ﺩﻭﺍﻡ ﻭ ﭘﺎﻳﺪﺍﺭﻱ ﺧﻮﺏ‬

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‫ﭘﺎﻳﻄﻦ ﺑﻮﺩﻥ ﻣﺨﺎﺭﺝ ﻧﮕﻬﺪﺍﺭﻱ‬

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‫ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺁﻧﺎﻟﻮﮒ ﻭ ﺩﻳﺠﻴﺘﺎﻝ‬

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‫ﻫﺰﻳﻨﻪ ﭘﺎﺋﻴﻦ ﺩﺭ ﺯﻣﺎﻥ ﺗﻮﺳﻌﻪ‬

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‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻧﺴﺒﺘﺎ" ﻭﺳﻴﻊ ﮐﻪ ﻣﻮﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﮐﺜﺮ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺍﺯ ﺟﻤﻠﻪ ﺗﻠﻪ‬ ‫ﮐﻨﻔﺮﺍﻧﺲ ﺻﻮﺗﻲ ﻭ ﺗﺼﻮﻳﺮﻱ ﺍﺳﺖ‪.‬‬

‫ﻣﻌﺎﻳﺐ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﻮﺍﮐﺴﻴﺎﻝ ‪:‬‬ ‫•‬

‫ﻣﺨﺎﺭﺝ ﺑﺎﻻﻱ ﻧﺼﺐ‬

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‫ﻧﺼﺐ ﻣﺸﮑﻞ ﺗﺮ ﻧﺴﺒﺖ ﺑﻪ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ‬

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‫ﻣﺤﺪﻭﺩﻳﺖ ﻓﺎﺻﻠﻪ‬

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‫ﻧﻴﺎﺯ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻋﻨﺎﺻﺮ ﺧﺎﺹ ﺑﺮﺍﻱ ﺍﻧﺸﻌﺎﺑﺎﺕ‬

‫ﺍﺯ ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ )‪ (Bayone -Neill - Concelman(BNC‬ﺑﻬﻤﺮﺍﻩ ﮐﺎﺑﻞ ﻫﺎﻱ‬

‫ﮐﻮﺍﮐﺴﻴﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻏﻠﺐ ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺍﺭﺍﻱ ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ ﻻﺯﻡ ﺩﺭ ﺍﻳﻦ‬ ‫ﺧﺼﻮﺹ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺷﺒﮑﻪ ﻭ ﺍﻧﻮﺍﻉ ﺁﻥ‬ ‫ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺯ ﺍﺗﺼﺎﻝ ﺩﻭ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺭ ﺍﺑﻌﺎﺩ ﻣﺘﻔﺎﻭﺕ ﻭ ﺑﺎ ﺍﻫﺪﺍﻑ ﮔﻮﻧﺎﮔﻮﻥ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ‪( LAN) Local-Area Networks‬ﻭ)‪(Wide-Area Networks‬‬

‫‪ ( WAN‬ﺩﻭ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ،LAN‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﻧﺎﺣﻴﻪ ﻣﺤﺪﻭﺩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﻧﻈﻴﺮ ﻣﻨﺰﻝ ﻭ ﻳﺎ ﻣﺤﻴﻂ ﮐﺎﺭ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ‬ ‫ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ،WAN‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻭ ﻳﺎ ﻣﺨﺎﺑﺮﺍﺗﻲ‪ ،‬ﺍﻣﻮﺍﺝ‬

‫ﺭﺍﺩﻳﻮﺋﻲ ﻭ ﺳﺎﻳﺮ ﮔﺰﻳــﻨﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‪ ،‬ﺩﺳﺘــــﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ ﻳﮏ ﺷﺒــﮑﻪ ﺑﻪ‬

‫ﻳﮑﺪﻳـــﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﭼﮕﻮﻧﻪ ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﻣﻲ ﮔﺮﺩﻧﺪ ؟‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺮ ﺍﺳﺎﺱ ﺳﻪ ﻭﻳﮋﮔﻲ ﻣﺘﻔﺎﻭﺕ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩ‪:‬‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻭ ﻣﻌﻤﺎﺭﻱ‬ ‫•‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ ،‬ﻧﺤﻮﻩ ﺍﺳﺘﻘﺮﺍﺭ) ﺁﺭﺍﻳﺶ( ﻫﻨﺪﺳﻲ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻦ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ‬

‫‪ bus , ring‬ﻭ‪ ، star‬ﺳﻪ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ "ﺍﺗﺮﻧﺖ" ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺩﺭ ﺑﺮﺧﻲ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ Token Ring‬ﺷﺮﮐﺖ ‪IBM‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ .‬ﭘﺮﻭﺗﮑﻞ‪ ،‬ﺩﺭ ﺣﻘﻴﺖ ﺑﻪ ﻣﻨﺰﻟﻪ ﻳﮏ ﺍﻋﻼﻣﻴﻪ ﺭﺳﻤﻲ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺁﻥ‬

‫ﻗﻮﺍﻧﻴﻦ ﻭ ﺭﻭﻳﻪ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻭﻳﺎ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ‪ ،‬ﺗﻌﺮﻳﻒ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﺍﺭﺍﻱ ﺩﻭ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﺩﺳﺘﮕﺎﻩ )ﻧﻈﻴﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ( ﺑﺎﺷﻴﻢ ﻭ ﺑﺨﻮﺍﻫﻴﻢ ﺁﻧﺎﻥ‬ ‫ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﻗﻄﻌﺎ" ﺑﻪ ﻭﺟﻮﺩ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺩﺭ ﺷﺒﮑﻪ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﺗﺎﮐﻨﻮﻥ ﺻﺪﻫﺎ ﭘﺮﻭﺗﮑﻞ ﺑﺎ ﺍﻫﺪﺍﻑ ﻣﺘﻔﺎﻭﺕ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

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‫‪ TCP/IP‬ﻳﮑﻲ ﺍﺯ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺩﺭ ﺯﻣﻴﻨﻪ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﮐﻪ ﺧﻮﺩ ﺍﺯ ﻣﺠﻤﻮﻋﻪ‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﺩﻳﮕﺮ‪ ،‬ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺟﺪﻭﻝ ﺯﻳﺮ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ‬

‫‪ TCP/IP‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪ .‬ﺩﺭ ﮐﻨﺎﺭ ﺟﺪﻭﻝ ﻓﻮﻕ ‪ ،‬ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻧﻴﺰ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‬ ‫ﺍﺳﺖ ﺗﺎ ﻣﺸﺨﺺ ﮔﺮﺩﺩ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻓﻮﻕ ﺩﺭ ﭼﻪ ﻻﻳﻪ ﺍﻱ ﺍﺯ ﻣﺪﻝ‬

‫‪ OSI‬ﮐﺎﺭ ﻣﻲ ﮐﻨﻨﺪ‪ .‬ﺑﻪ ﻣﻮﺍﺯﺍﺕ ﺣﺮﮐﺖ ﺍﺯ ﭘﺎﺋﻴﻦ ﺗﺮﻳﻦ ﻻﻳﻪ )ﻻﻳﻪ ﻓﻴﺰﻳﮑﻲ( ﺑﻪ ﺑﺎﻻﺗﺮﻳﻦ‬ ‫ﻻﻳﻪ )ﻻﻳﻪ ‪ ،(Application‬ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭ ﻫﺮ ﻻﻳﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ‪ ،‬ﺯﻣﺎﻧﻲ ﺭﺍ ﺻﺮﻑ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪TCP/IP‬‬

‫ﻣﺪﻝ ﻣﺮﺟﻊ‬ ‫‪OSI‬‬

‫• ‪ OSI‬ﺍﺯ ﮐﻠﻤﺎﺕ ‪ Open Systems Interconnect‬ﺍﻗﺘﺒﺎﺱ ﻭ ﻳﮏ ﻣﺪﻝ ﻣﺮﺟﻊ‬ ‫ﺩﺭ ﺧﺼﻮﺹ ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﻴﻦ ﺩﻭ ﻧﻘﻄﻪ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻭ ﺍﺭﺗﺒﺎﻃﻲ ﺍﺳﺖ‪.‬‬ ‫ﻫﺪﻑ ﻋﻤﺪﻩ ﻣﺪﻝ ‪ ،OSI‬ﺍﺭﺍﺋﻪ ﺭﺍﻫﻨﻤﺎﺋﻲ ﻫﺎﻱ ﻻﺯﻡ ﺑﻪ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﻣﺤﺼﻮﻻﺕ‬ ‫ﺷﺒﮑﻪ ﺍﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻮﻟﻴﺪ ﻣﺤﺼﻮﻻﺕ ﺳﺎﺯﮔﺎﺭ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺖ‪.‬‬

‫ﻣﺪﻝ ‪ OSI‬ﺗﻮﺳﻂ ﮐﻤﻴﺘﻪ ‪ IEEE‬ﺍﻳﺠﺎﺩ ﺗﺎ ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ‬ ‫ﮐﻨﻨﺪﮔﺎﻥ ﻣﺘﻌﺪﺩ ﻗﺎﺩﺭ ﺑﻪ ﮐﺎﺭ ﻭ ﻳﺎ ﺳﺎﺯﮔﺎﺭﻱ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺸﮑﻞ ﻋﺪﻡ ﺳﺎﺯﮔﺎﺭﻱ‬ ‫ﺑﻴﻦ ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪﺷﺪﻩ ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﻫﺎﻱ ﺑﺰﺭﮒ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺯﻣﺎﻧﻲ‬

‫ﺁﻏﺎﺯ ﮔﺮﺩﻳﺪ ﮐﻪ ﺷﺮﮐﺖ ‪ HP‬ﺗﺼﻤﻴﻢ ﺑﻪ ﺍﻳﺠﺎﺩ ﻣﺤﺼﻮﻻﺕ ﺷﺒﮑﻪ ﺍﻱ ﻧﻤﻮﺩ ﻭ‬ ‫ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ‪ HP‬ﺑﺎ ﻣﺤﺼﻮﻻﺕ ﻣﺸﺎﺑﻪ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺷﺮﮐﺖ‬

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‫ﻫﺎﻱ ﺩﻳﮕﺮ ﻧﻈﻴﺮ ‪ ،IBM‬ﺳﺎﺯﮔﺎﺭ ﻧﺒﻮﺩ‪ .‬ﻣﺜﻼ" ﺯﻣﺎﻧﻲ ﮐﻪ ﺷﻤﺎ ﭼﻬﻞ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺭﺍ ﺑﺮﺍﻱ‬ ‫ﺷﺮﮐﺖ ﺧﻮﺩ ﺗﻬﻴﻪ ﻣﻲ ﻧﻤﻮﺩﻳﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺳﺎﻳﺮ ﺗﺠﻬﻴﺰﺍﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺷﺒﮑﻪ ﻧﻴﺰ ﺍﺯ‬

‫ﻫﻤﺎﻥ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺧﺮﻳﺪﺍﺭﻱ ﻣﻲ ﮔﺮﺩﻳﺪ)ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﻭﺟﻮﺩ ﺳﺎﺯﮔﺎﺭﻱ ﺑﻴﻦ ﺁﻧﺎﻥ(‪.‬‬ ‫ﻣﺸﮑﻞ ﻓﻮﻕ ﭘﺲ ﺍﺯ ﻣﻌﺮﻓﻲ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ ،OSI‬ﺑﺮﻃﺮﻑ ﮔﺮﺩﻳﺪ‪.‬‬ ‫ﻣﺪﻝ ‪ OSI‬ﺩﺍﺭﺍﻱ ﻫﻔﺖ ﻻﻳﻪ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ‬

‫ﻋﻤﻠﻴﺎﺗﻲ ﺧﺎﺻﻲ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺎﻻﺗﺮﻳﻦ ﻻﻳﻪ‪ ،‬ﻻﻳﻪ ﻫﻔﺖ ) ‪ ( Application‬ﻭ‬ ‫ﭘﺎﺋﻴﻦ ﺗﺮﻳﻦ ﻻﻳﻪ‪ ،‬ﻻﻳﻪ ﻳﮏ )‪ (Physiacal‬ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﺍﺭﺳﺎﻝ‬ ‫ﺩﺍﺩﻩ ﺑﺮﺍﻱ ﻳﮏ ﮐﺎﺭﺑﺮ ﺩﻳﮕﺮ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪ ،‬ﺩﺍﺩﻩ ﻫﺎ ﺣﺮﮐﺖ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻻﻳﻪ ﻫﻔﺘﻢ‬

‫ﺷﺮﻭﻉ ﻧﻤﻮﺩﻩ ﻭ ﭘـﺲ ﺍﺯ ﺗـــﺒﺪﻳﻞ ﺑﻪ ﺳﮕﻤﻨﺖ‪ ،datagram ،‬ﺑﺴـﺘﻪ‬ ‫ﺍﻃﻼﻋــــــﺎﺗﻲ‬

‫) ‪ ( Packet‬ﻭ ﻓﺮﻳﻢ‪ ،‬ﺩﺭ ﻧﻬﺎﻳﺖ ﺩﺭ ﻃﻮﻝ ﮐﺎﺑﻞ ) ﻋﻤﻮﻣﺎ" ﮐﺎﺑﻞ‬

‫ﻫﺎﻱ ‪ ( twisted pair‬ﺍﺭﺳﺎﻝ ﺗﺎ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﺮﺳﺪ‪.‬‬ ‫•‬

‫ﻣﻌﻤﺎﺭﻱ ‪ ،‬ﺑﻪ ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﻣﻌﻤﺎﺭﻱ ﮐﻪ ﻋﻤﺪﺗﺎ" ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺍﺷﺎﺭﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ Peer- Peer-To :‬ﻭ ‪ .Server - Client‬ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ‪ Peer-To-Peer‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺧﺘﺼﺎﺻﻲ ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺍﺯ‬

‫ﻃﺮﻳﻖ ‪ workgroup‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ‪ ،‬ﭼﺎﭘﮕﺮﻫﺎ ﻭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪،‬‬ ‫ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫•‬

‫] ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ، Server - Client‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭ ﻳﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻧﻲ‬ ‫ﺍﺧﺘﺼﺎﺻﻲ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ) ﻧﻈﻴﺮ ﻳﮏ ﮐﻨﺘﺮﻝ ﮐﻨﻨﺪﻩ ‪ Domain‬ﺩﺭ ﻭﻳﻨﺪﻭﺯ ( ﮐﻪ ﺗﻤﺎﻣﻲ‬

‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻫﺎ ﻭ ﺧﺪﻣﺎﺕ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‪ ،‬ﺑﻪ ﺁﻥ‬ ‫‪ log on‬ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﮐﺜﺮ ﺳﺎﺯﻣﺎﻥ ﻭ ﻣﻮﺳﺴﺎﺕ ﺍﺯ ﻣﻌﻤﺎﺭﻱ ‪Server - Client‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫‪ MAC Address‬ﭼﻴﺴﺖ؟‬ ‫ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒــﮑﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳـﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫ﺷﻨﺎﺳﺎﺋﻲ ﻭ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﻣﻨﺤﺼﺮﺑﻔﺮﺩ ﺑﺎﺷﺪ ‪ .‬ﻗﻄﻌﺎ" ﺗﺎﮐﻨﻮﻥ ﺑﺎ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻭ ﻳـﺎ‬ ‫‪ ) MAC‬ﺍﻗﺘﺒﺎﺱ ﺷﺪﻩ ﺍﺯ ﮐﻠﻤﺎﺕ ‪ ( Media Access Control‬ﺑﺮﺧﻮﺭﺩ ﺩﺍﺷﺘﻪ ﺍﻳﺪ‬

‫ﻭ ﺷﺎﻳﺪ ﺍﻳﻦ ﺳﻮﺍﻝ ﺑﺮﺍﻱ ﺷﻤﺎ ﻣﻄﺮﺡ ﺷﺪﻩ ﺑﺎﺷﺪ ﮐﻪ ﺍﻭﻻ" ﺿﺮﻭﺭﺕ ﻭﺟﻮﺩ ﺩﻭ ﻧﻮﻉ ﺁﺩﺭﺱ‬

‫ﭼﻴﺴﺖ ﻭ ﺛﺎﻧﻴﺎ" ﺟﺎﻳﮕﺎﻩ ﺍﺳﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﭼﻴﺴﺖ؟‬

‫‪ ، MAC Address‬ﻳﮏ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﺍﺳﺖ ﺩﺭ ﺣﺎﻟﻲ ﮐﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ ، IP‬ﺑﻪ ﻣﻨﺰﻟﻪ‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨﻄﻘﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨﻄﻘﻲ ﺷﻤﺎ ﺭﺍ ﻣﻠﺰﻡ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﮐﻪ ﺑﻪ ﻣﻨــﻈﻮﺭ‬ ‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﮐﺎﺭﺕ ﺷﺒﮑﻪ‪ ،‬ﺩﺭﺍﻳﻮﺭﻫﺎ ﻭ ﻳﺎ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺧﺎﺻـﻲ ﺭﺍ ﺩﺭ ﺣﺎﻓــﻈﻪ‬

‫ﻣﺴﺘﻘﺮ ﻧﻤﺎﺋﻴﺪ ) ﻣﺜﻼ" ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ .( IP‬ﺍﻳﻦ ﻭﺿﻌﻴﺖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ‬ ‫‪ MAC Address‬ﺻﺪﻕ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ ﻭ ﺍﻳﻨﮕﻮﻧﻪ ﺁﺩﺭﺱ ﻫﺎ ﻧﻴﺎﺯﻣﻨﺪ ﺩﺭﺍﻳﻮﺭﻫﺎﻱ ﺧﺎﺻﻲ‬ ‫ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ ‪ ،‬ﭼﺮﺍﮐﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﺩﺭﻭﻥ ﺗﺮﺍﺷﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﻧﺪ‪.‬‬ ‫ﺩﻟﻴﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪MAC Address‬‬

‫ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻫﺎﺋﻲ ﺧﺎﺹ ﺷﻨﺎﺳﺎﺋﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﺮﺍﻱ ﺷﻨﺎﺳﺎﺋﻲ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ‪ ،‬ﺻﺮﻑ ﺩﺍﺷﺘﻦ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺑﻪ ﺗﻨﻬﺎﺋﻲ‬ ‫ﮐﻔﺎﻳﺖ ﻧﺨﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺣﺘﻤﺎ" ﻋﻼﻗﻪ ﻣﻨﺪﻳﺪ ﮐﻪ ﻋﻠﺖ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺭﺍ ﺑﺪﺍﻧﻴﺪ ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ‪ ،‬ﻻﺯﻡ‬ ‫ﺍﺳﺖ ﻧﮕﺎﻫﻲ ﺑﻪ ﻣﺪﻝ ﻣﻌﺮﻭﻑ ‪ ( OSI (Open Systems Interconnect‬ﻭ ﻻﻳﻪ‬

‫ﻫﺎﻱ ﺁﻥ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪:‬‬

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‫ﻣﺪﻝ ‪OSI‬‬ ‫‪...‬‬ ‫‪ Network‬ﻻﻳﻪ ﺳﻮﻡ ﺁﺩﺭﺱ ‪ IP‬ﺩﺭ ﺍﻳﻦ‬ ‫‪Layer‬‬ ‫ﻻﻳﻪ ﻗﺮﺍﺭ ﺩﺍﺭﺩ‬ ‫‪ DataLink‬ﻻﻳﻪ ﺩﻭﻡ ﺁﺩﺭﺱ ‪ MAC‬ﺩﺭ‬ ‫‪Layer‬‬ ‫ﺍﻳﻦ ﻻﻳﻪ ﻗﺮﺍﺭ ﺩﺍﺭﺩ‬ ‫‪Physical‬‬ ‫‪Layer‬‬

‫ﻻﻳﻪ ﺍﻭﻝ‬ ‫ﺷﺒﮑﻪ ﻓﻴﺰﻳﮑﻲ‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ ‪ MAC Address ،‬ﺩﺭ ﻻﻳﻪ ‪ ) DataLink‬ﻻﻳﻪ ﺩﻭﻡ‬

‫ﻣﺪﻝ ‪ ( OSI‬ﻗﺮﺍﺭ ﺩﺍﺭﺩ ﻭ ﺍﻳﻦ ﻻﻳﻪ ﻣﺴﺌﻮﻝ ﺑﺮﺭﺳﻲ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ﮐﻪ ﺩﺍﺩﻩ ﻣﺘﻌﻠﻖ‬ ‫ﺑﻪ ﮐﺪﺍﻣﻴﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬ ‫ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ) ‪ ( Packet‬ﺑﻪ ﻻﻳﻪ ‪ Datalink‬ﻣﻲ ﺭﺳﺪ ) ﺍﺯ ﻃﺮﻳﻖ ﻻﻳﻪ‬

‫ﺍﻭﻝ (‪ ،‬ﻭﻱ ﺁﻥ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ ﺑﺎﻻﺋﻲ ﺧﻮﺩ ) ﻻﻳﻪ ﺳﻮﻡ ( ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﺎ‬

‫ﻧﻴﺎﺯﻣﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﺧﺎﺻﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺳﺎﺋﻲ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺒﻞ ﺍﺯ ﻻﻳﻪ ﺳﻮﻡ ﻫﺴـﺘﻴﻢ‪.‬‬ ‫‪ ،MAC Address‬ﺩﺭ ﭘﺎﺳﺦ ﺑﻪ ﻧﻴﺎﺯ ﻓﻮﻕ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﻭ ﺑﺎ ﺍﺳـﺘﻘﺮﺍﺭ ﺩﺭ ﻻﻳﻪ ﺩﻭﻡ‪،‬‬

‫ﻭﻇﻴﻔﻪ ﺷﻨﺎﺳﺎﺋﻲ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺒﻞ ﺍﺯ ﻻﻳﻪ ﺳﻮﻡ ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﺗﻤﺎﻣﻲ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ‬ ‫ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺑﺮﺭﺳﻲ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻧﻤﻮﺩﻩ ﺗﺎ ﻣﺸﺨﺺ ﮔﺮﺩﺩ ﮐﻪ ﺁﻳﺎ‬

‫‪ MAC Address‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺨﺶ "ﺁﺩﺭﺱ ﻣﻘﺼﺪ " ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺑﺎ ﺁﺩﺭﺱ‬ ‫ﺁﻧﺎﻥ ﻣﻄﺎﺑﻘﺖ ﻣﻲ ﻧﻤﺎﻳﺪ؟ ﻻﻳﻪ ﻓﻴﺰﻳﮑﻲ) ﻻﻳﻪ ﺍﻭﻝ ( ﻗﺎﺩﺭ ﺑﻪ ﺷﻨﺎﺧﺖ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ‬

‫ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﻭ ﻓﺮﻳﻢ ﻫﺎﺋﻲ ﺭﺍ ﺗﻮﻟﻴﺪ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ‪Datalink‬‬ ‫ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﻣﻄﺎﺑﻘﺖ ‪ MAC Address‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺨﺶ "ﺁﺩﺭﺱ ﻣﻘﺼﺪ‬ ‫" ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺑﺎ ‪ MAC Address‬ﻳﮑﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‪،‬‬ ‫‪130‬‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺁﻥ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺑﺎ ﺍﺭﺳﺎﻝ ﺁﻥ ﺑﻪ ﻻﻳﻪ ﺳﻮﻡ ‪ ،‬ﺁﺩﺭﺱ ﺷﺒﮑﻪ ﺍﻱ ﺑﺴﺘﻪ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ) ‪ ( IP‬ﺑﺮﺭﺳﻲ ﺗﺎ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺣﺎﺻﻞ ﮔﺮﺩﺩ ﮐﻪ ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﺎ ﺁﺩﺭﺱ ﺷﺒﮑﻪ ﺍﻱ‬ ‫ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎ ﺁﻥ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﺪﻩ ﺍﺳﺖ ﺑﺪﺭﺳﺘﻲ ﻣﻄﺎﺑﻘﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺳﺎﺧﺘﺎﺭ ‪MAC Address‬‬

‫ﻳﮏ ‪ MAC Address‬ﺑﺮ ﺭﻭﻱ ﻫﺮ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻫﻤﻮﺍﺭﻩ ﺩﺍﺭﺍﻱ ﻃﻮﻟﻲ ﻣﺸﺎﺑﻪ ﻭ ﻳﮑﺴﺎﻥ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ ) .‬ﺷﺶ ﺑﺎﻳﺖ ﻭ ﻳﺎ ‪ ٤٨‬ﺑﻴﺖ (‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﺭﺳﻲ ‪ Address MAC‬ﻳﮏ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺁﻥ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺁﻥ ﺭﺍ ﺑﺎ ﻓﺮﻣﺖ ﻣﺒﻨﺎﻱ ﺷﺎﻧﺰﺩﻩ‬ ‫) ‪ ،( Hex‬ﻣﺸﺎﻫﺪﻩ ﺧﻮﺍﻫﻴﺪ ﺩﻳﺪ ‪ .‬ﻣﺜﻼ" ‪ MAC Address‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ‬

‫ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﺻﻮﺭﺕ ﺯﻳﺮ ﺑﺎﺷﺪ‪:‬‬ ‫ﻣﺸﺎﻫﺪﻩ ‪MAC Address‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺳﺘﻮﺭ ‪ IPconfig/all‬ﻭ ﻣﺸﺎﻫﺪﻩ ﺑﺨﺶ ‪Physical‬‬ ‫‪: address‬‬ ‫‪BA‬‬ ‫‪50‬‬ ‫‪00‬‬ ‫ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺗﻮﺳﻂ‬

‫‪6A‬‬ ‫‪DB‬‬ ‫‪79‬‬ ‫ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ‬

‫‪ IEEE‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ‪RFC‬‬ ‫‪١٧٠٠‬‬

‫ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﻧﻈﻴﺮ ﺍﻳﻨﺘﻞ‪ ،‬ﮐﺎﺭﺕ ﻫﺎ ﻱ ﺷﺒﮑﻪ ﺧﻮﺩ ﺭﺍ ﺗﻮﻟﻴﺪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺁﻧﺎﻥ ﻫﺮ‬

‫ﺁﺩﺭﺱ ﺩﻟﺨﻮﺍﻫﻲ ﺭﺍ ﻧﻤﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺮﺍﻱ ‪ MAC Address‬ﺩﺭ ﻧﻈﺮ ﺑﮕﻴﺮﻧﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬ ‫ﺗﻤﺎﻣﻲ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺑﺨﻮﺍﻫﻨﺪ ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﻳﮏ ﺿﺎﺑﻄﻪ ﺧﺎﺹ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ‬ ‫ﺗﻌﺮﻳﻒ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻗﻄﻌﺎ" ﺍﻣﮑﺎﻥ ﺗﻌﺎﺭﺽ ﺑﻴﻦ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ‬

‫ﺁﻣﺪ‪ ) .‬ﻋﺪﻡ ﺗﺸﺨﻴﺺ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﮐﺎﺭﺕ ﻭ ﻭﺟﻮﺩ ﺩﻭ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﺯ ﺩﻭ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺑﺎ ﺁﺩﺭﺱ ﻫﺎﻱ ﻳﮑﺴﺎﻥ (‪ .‬ﺣﺘﻤﺎ" ﺍﻳﻦ ﺳﻮﺍﻝ ﺑﺮﺍﻱ ﺷﻤﺎ ﻣﻄﺮﺡ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ‬

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‫‪ MAC Address‬ﺗﻮﺳﻂ ﭼﻪ ﺍﻓﺮﺍﺩ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻥ ﻫﺎﺋﻲ ﻭ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺑﻪ ﮐﺎﺭﺕ ﻫﺎﻱ‬

‫ﺷﺒﮑﻪ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ؟ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﺧﻮﺭﺩ ﺑﺎ ﻣﺸﮑﻼﺕ ﻓﻮﻕ‪ ،‬ﮔﺮﻭﻩ ‪ ، IEEE‬ﻫﺮ‬ ‫‪ MAC Address‬ﺭﺍ ﺑﻪ ﺩﻭ ﺑﺨﺶ ﻣﺴﺎﻭﻱ ﺗﻘﺴﻴﻢ ﮐﻪ ﺍﺯ ﺍﻭﻟﻴﻦ ﺑﺨﺶ ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺷﻨﺎﺳﺎﺋﻲ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﮐﺎﺭﺕ ﻭ ﺩﻭﻣﻴﻦ ﺑﺨﺶ ﺑﻪ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺍﺧﺘﺼﺎﺹ ﺩﺍﺩﻩ ﺷﺪﻩ ﺗﺎ ﺁﻧﺎﻥ‬

‫ﻳﮏ ﺷﻤﺎﺭﻩ ﺳﺮﻳﺎﻝ ﺭﺍ ﺩﺭ ﺁﻥ ﺩﺭﺝ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﮐﺪ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺑﺮ ﺍﺳﺎﺱ ‪ RFC-1700‬ﺑﻪ ﺁﻧﺎﻥ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ‬ ‫ﻣﺸﺎﻫﺪﻩ ‪ RFC‬ﻓﻮﻕ ﺣﺘﻤﺎ" ﻣﺘﻮﺟﻪ ﺧﻮﺍﻫﻴﺪ ﺷﺪ ﮐﻪ ﺑﺮﺧﻲ ﺍﺯ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺩﺍﺭﺍﻱ ﺑﻴﺶ ﺍﺯ‬

‫ﻳﮏ ﮐﺪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺑﻪ ﺣﺠﻢ ﮔﺴﺘﺮﺩﻩ ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪﻱ ﺁﻧﺎﻥ ﺑﺮﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﺎ ﺍﻳﻦ ﮐﻪ ‪ MAC Address‬ﺩﺭ ﺣﺎﻓﻈﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺛﺒﺖ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺑﺮﺧﻲ ﺍﺯ ﺗﻮﻟﻴﺪ‬ ‫ﮐﻨﻨﺪﮔﺎﻥ ﺑﻪ ﺷﻤﺎ ﺍﻳﻦ ﺍﺟﺎﺯﻩ ﺭﺍ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ ﮐﻪ ﺑﺎ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺧﺎﺹ‪،‬‬ ‫ﺑﺘﻮﺍﻧﻴﺪ ﺑﺨﺶ ﺩﻭﻡ ‪ MAC Address‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺧﻮﺩ ﺭﺍ ﺗﻐﻴﻴﺮ ﺩﻫﻴﺪ) ﺷﻤﺎﺭﻩ ﺳﺮﻳﺎﻝ‬ ‫ﮐﺎﺭﺕ ﺷﺒﮑﻪ ( ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﺠﺪﺩ ﺍﺯ ﺳﺮﻳﺎﻝ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺳﺎﻳﺮ‬

‫ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺁﻧﺎﻥ ﺑﺮﻣﻲ ﮔﺮﺩﺩ )ﺗﺠﺎﻭﺯ ﺍﺯ ﻣﺤﺪﻭﺩ ﻣﻮﺭﺩ ﻧﻈﺮ(‪.‬‬ ‫ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺍﺣﺘﻤﺎﻝ ﺍﻳﻦ ﮐﻪ ﺷﻤﺎ ﺩﻭ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺭﺍ ﺧﺮﻳﺪﺍﺭﻱ ﻧﻤﺎﺋﻴﺪ ﮐﻪ ﺩﺍﺭﺍﻱ ‪MAC‬‬

‫‪ Address‬ﻳﮑﺴﺎﻧﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﺴﻴﺎﺭ ﺿﻌﻴﻒ ﻭ ﺷﺎﻳﺪ ﻫﻢ ﻏﻴﺮﻣﻤﮑﻦ ﺑﺎﺷﺪ‪.‬‬

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‫ﻣﺪﻝ ﻣﺮﺟﻊ ‪OSI‬‬ ‫‪ OSI‬ﺍﺯ ﮐﻠﻤﺎﺕ ‪ Open Systems Interconnect‬ﺍﻗﺘﺒﺎﺱ ﻭ ﻳﮏ‬

‫ﻣﺪﻝ ﻣﺮﺟﻊ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﻴﻦ ﺩﻭ ﻧﻘﻄﻪ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻭ ﻳﺎ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‪ .‬ﻫﺪﻑ ﻋﻤﺪﻩ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﺍﺭﺍﺋﻪ ﺗﻮﺻﻴﻪ ﻫﺎ ﻭ ﺭﺍﻫﻨﻤﺎﺋﻲ ﻫﺎﻱ ﻻﺯﻡ ﺑﻪ ﺗﻮﻟﻴﺪ‬ ‫ﮐﻨﻨﺪﮔﺎﻥ ﻣﺤﺼﻮﻻﺕ ﺷﺒﮑﻪ ﺍﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻮﻟﻴﺪ ﻣﺤﺼﻮﻻﺗﻲ ﺳﺎﺯﮔﺎﺭ ﺑﺎ ﺳﺎﻳﺮ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ‬

‫ﺍﺳﺖ‪.‬‬

‫ﻣﺪﻝ ‪ OSI‬ﺗﻮﺳﻂ ﮐﻤﻴﺘﻪ ‪ IEEE‬ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﻣﺤﺼﻮﻻﺕ‬ ‫ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﻣﺨﺘﻠﻒ ﺍﻣﮑﺎﻥ ﮐﺎﺭ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‬ ‫) ﺳﺎﺯﮔﺎﺭﻱ ﺑﻴﻦ ﻣﺤﺼﻮﻻﺕ (‪ .‬ﻣﺸﮑﻞ ﻋﺪﻡ ﺳﺎﺯﮔﺎﺭﻱ ﺑﻴﻦ ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪﺷﺪﻩ ﺗﻮﺳﻂ‬

‫ﺷﺮﮐﺖ ﻫﺎﻱ ﺑﺰﺭﮒ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ‪ ،‬ﺯﻣﺎﻧﻲ ﺁﻏﺎﺯ ﮔﺮﺩﻳﺪ ﮐﻪ ﺷﺮﮐﺖ‬ ‫‪ HP‬ﺗﺼﻤﻴﻢ ﺑﻪ ﺗﻮﻟﻴﺪ ﻳﮏ ﻣﺤﺼﻮﻝ ﺷﺒﮑﻪ ﺍﻱ ﻧﻤﻮﺩ ﻭ ﺍﻳﻦ ﻣﺤﺼﻮﻝ ﺑﺎ ﻣﺤﺼﻮﻻﺕ ﻣﺸﺎﺑﻪ‬ ‫ﺳﺎﻳﺮ ﺷﺮﮐﺖ ﻫﺎ ) ﻣﺜﻼ" ‪ ( IBM‬ﺳﺎﺯﮔﺎﺭ ﻧﺒﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺸﮑﻞ ﻓﻮﻕ‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬

‫ﻗﺼﺪ ﺗﻬﻴﻪ ﭼﻬﻞ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﺳﺎﺯﻣﺎﻥ ﺧﻮﺩ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺳﺎﻳﺮ‬ ‫ﺗﺠﻬﻴﺰﺍﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺷﺒﮑﻪ ﺭﺍ ﻧﻴﺰ ﺍﺯ ﻫﻤﺎﻥ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺗﻬﻴﻪ ﻣﻲ ﻧﻤﻮﺩﻳﺪ )ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ‬ ‫ﺳﺎﺯﮔﺎﺭﻱ ﺑﻴﻦ ﺁﻧﺎﻥ (‪ .‬ﻣﺸﮑﻞ ﻓﻮﻕ ﺗﺎ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻫﻤﭽﻨﺎﻥ ﻭﺟﻮﺩ ﺩﺍﺷﺖ‬

‫ﻭ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﻣﻌﻈﻞ ﺑﺰﺭﮒ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻄﺮﺡ ﺑﻮﺩ‪.‬‬

‫ﻣﺪﻝ ‪ OSI‬ﺩﺍﺭﺍﻱ ﻫﻔﺖ ﻻﻳﻪ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺗﻲ‬ ‫ﺧﺎﺹ ‪ ،‬ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺎﻻﺗﺮﻳﻦ ﻻﻳﻪ‪ ،‬ﻻﻳﻪ ﻫﻔﺖ ﻭ ﭘﺎﺋﻴﻦ ﺗﺮﻳﻦ ﻻﻳﻪ‪ ،‬ﻻﻳﻪ ﻳﮏ ﺍﺳﺖ‪ .‬ﺩﺭ‬

‫ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ‪ ،‬ﺩﺍﺩﻩ ﻫﺎ ﺣﺮﮐﺖ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻻﻳﻪ ﻫﻔﺘﻢ‬ ‫ﺁﻏﺎﺯ ﻧﻤﻮﺩﻩ ﻭ ﭘﺲ ﺍﺯ ﺗﺒﺪﻳﻞ ﺑﻪ ﺳﮕﻤﻨﺖ‪ ،‬ﺩﻳﺘﺎﮔﺮﺍﻡ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ) ‪ ( Packet‬ﻭ ﻓﺮﻳﻢ‪،‬‬ ‫ﺩﺭ ﻧﻬﺎﻳﺖ ﺍﺯ ﻃﺮﻳﻖ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ) ﻣﺜﻼ" ﮐﺎﺑﻞ ( ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﻋﻤﻠﮑﺮﺩ ﻫﺮ ﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ ﻣﺪﻝ ﻣﺮﺟﻊ ‪: OSI‬‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Application‬ﻻﻳﻪ ﻫﻔﺘﻢ (‬

‫□ ﺍﺭﺍﺋﻪ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺷﺒﮑﻪ ﺑﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎ)ﻧﻈﻴﺮ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ‪ ،‬ﺍﺭﺳﺎﻝ ﻓﺎﻳﻞ ﻫﺎ ﻭ‪(...‬‬ ‫□ ﺗﺸﺨﻴﺺ ﺯﻣﺎﻥ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺷﺒﮑﻪ‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Presentation‬ﻻﻳﻪ ﺷﺸﻢ (‬

‫□ ﺍﻳﺠﺎﺩ ﺍﻃﻤﻴﻨﺎﻥ ﻻﺯﻡ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺑﻮﺩﻥ ﺩﺍﺩﻩ ﺑﺮﺍﻱ ﺳﻴﺴﺘﻢ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ‬ ‫□ ﻓﺮﻣﺖ ﺩﺍﺩﻩ‬

‫□ ﺳﺎﺧﺘﻤﺎﻥ ﻫﺎﻱ ﺩﺍﺩﻩ‬ ‫□ ﺗﻮﺍﻓﻖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﮔﺮﺍﻣﺮ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺑﺮﺍﻱ ﻻﻳﻪ ‪Application‬‬ ‫□ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺩﺍﺩﻩ‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Session‬ﻻﻳﻪ ﭘﻨﺠﻢ (‬

‫•‬

‫ﻻﻳﻪ ‪ ) Transport‬ﻻﻳﻪ ﭼﻬﺎﺭﻡ (‬

‫□ ﺍ ﻳﺠﺎﺩ ‪ ،‬ﻣﺪﻳﺮﻳﺖ ﻭ ﺧﺎﺗﻤﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﺷﺪﻩ ﺑﻴﻦ ﺑﺮﻧﺎﻣﻪ ﻫﺎ‬ ‫□ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺭﻭﻳﮑﺮﺩﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺣﻤﻞ ﺩﺍﺩﻩ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ‬ ‫□ ﺣﻤﻞ ﻣﻄﻤﺌﻦ ﺩﺍﺩﻩ‬

‫□ ﺍﻳﺠﺎﺩ ‪ ،‬ﻣﺪﻳﺮﻳﺖ ﻭ ﺧﺎﺗﻤﻪ ﻣﺪﺍﺭﺍﺕ ﻣﺠﺎﺯﻱ‬ ‫‪134‬‬

‫□ ﺗﺸﺨﻴﺺ ﻭ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻥ ﺧﻄﺎﺀ‬

‫□ ﺗﻘﺴﻴﻢ ﺩﺍﺩﻩ ﺑﻪ ﻓﺮﻳﻢ ﻭ ﻧﺴﺒﺖ ﺩﻫﻲ ﻳﮏ ﺩﻧﺒﺎﻟﻪ ﻋﺪﺩﻱ ﻣﻨﺎﺳﺐ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ‬ ‫□ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ UDP ،TCP‬ﻭ ‪ SPX‬ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Network‬ﻻﻳﻪ ﺳﻮﻡ (‬

‫□ ﺍﺭﺍﺋﻪ ﺍﺭﺗﺒﺎﻁ ﻭ ﻣﺴﻴﺮ ﺍﻧﺘﺨﺎﺑﻲ ﺑﺮﺍﻱ ﺩﻭ ﺳﻴﺴﺘﻢ‬ ‫□ ﺣﻮﺯﻩ ﺭﻭﺗﻴﻨﮓ‬

‫□ ﭘﺎﺳﺦ ﺑﻪ ﺳﻮﺍﻻﺕ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ﻧﺤﻮﻩ ﺍﺭﺗﺒﺎﻁ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﮕﻤﻨﺖ‬ ‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺷﺒﮑﻪ‬ ‫□ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﺒﺪﺍﺀ‪ ،‬ﻣﻘﺼﺪ‪ Subnet ،‬ﻭ ﺗﺸﺨﻴﺺ ﻣﺴﻴﺮ ﻻﺯﻡ‬ ‫□ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ IP‬ﻭ ‪ IPX‬ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Datalink‬ﻻﻳﻪ ﺩﻭﻡ (‬ ‫□ ﺍﻧﺘﻘﺎﻝ ﻣﻄﻤﺌﻦ ﺩﺍﺩﻩ ﺍﺯ ﻃﺮﻳﻖ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‬

‫□ ﺁﺩﺭﺱ ﺩﻫﻲ ﻓﻴﺰﻳﮑﻲ ﻭ ﻳﺎ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ) ‪ ،( MAC‬ﺗﻮﭘﻮﻟﻮﮊﻱ ﺷﺒﮑﻪ‬ ‫□ ﻓﺮﻳﻢ ﻫﺎ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ‪ ) Physical‬ﻻﻳﻪ ﺍﻭﻝ (‬

‫□ ﮐﺎﺑﻞ ﻫﺎ ‪ ،‬ﮐﺎﻧﮑﺘﻮﺭﻫﺎ‪ ،‬ﻭﻟﺘﺎﮊﻫﺎ‪ ،‬ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ‬ ‫□ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﺻﻮﺭﺕ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺑﻴﺖ ﻫﺎ‪ ،‬ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﻭ‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ‬

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‫‪OSI‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﻣﻨﺎﺳﺐ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﭘﺮﻭﺗﮑﻞ ﺩﺭ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺑﺮﺧﻲ ﺍﺯ‬

‫ﻣﺪﻝ ﻫﺎﻱ ﺭﺍﻳﺞ ﺷﺒﮑﻪ ﮐﻪ ﻣﻌﻤﺎﺭﻱ ﺷﺒﮑﻪ ﺭﺍ ﺗﺸﺮﻳﺢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺁﺷﻨﺎ ﮔﺮﺩﻳﺪ‪.‬‬

‫ﻣﺪﻝ ‪ ( Open Systems Interconnection ) OSI‬ﻳﮏ ﻣﺮﺟﻊ ﻣﻨﺎﺳﺐ‬ ‫ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﻣﺪﻝ ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٤‬ﺗﻮﺳﻂ ‪) ISO‬ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﻴﻦ ﺍﻟﻤﻠﻠﻲ‬

‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺳﺎﺯﻱ ﺑﺎ ﺑﻴﺶ ﺍﺯ ‪ ١٣٠‬ﻋﻀﻮ( ﺍﺭﺍﺋﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﺍﺯ ﻫﻔﺖ ﻻﻳﻪ ﺑﺮﺍﻱ‬

‫ﺗﺸﺮﻳﺢ ﻓﺮﺁﻳﻨﺪﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺮﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎ ﻣﺴﻴﻮﻟﻴﺖ ﺍﻧﺠﺎﻡ‬ ‫ﻋﻤﻠﻴﺎﺕ ﺧﺎﺻﻲ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﻧﺪ‪ ..‬ﻣﺪﻝ ‪ OSI‬ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﻣﺮﺟﻊ ﻭ ﺭﺍﻫﻨﻤﺎ ﺑﺮﺍﻱ ﺷﻨﺎﺧﺖ‬ ‫ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺷﻨﺎ ﺋﻲ ﺑﺎ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﻳﮏ‬

‫ﺷﺒﮑﻪ‪ ،‬ﻣﻄﺎﻟﻌﻪ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﻣﻔﻴﺪ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻫﻔﺖ ﻻﻳﻪ ﻣﺪﻝ ‪ OSI‬ﺭﺍ ﻧﺸﺎﻥ‬ ‫ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻳﻖ ﻻﻳﻪ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ‬ ‫ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺍﺩﻩ ﻫﺎ ﺗﻮﺳﻂ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻭ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮ ﺗﻮﻟﻴﺪ ﺧﻮﺍﻫﻨﺪ ﺷﺪ ) ﻧﻈﻴﺮ ﻳﮏ‬ ‫ﭘﻴﺎﻡ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ(‪ .‬ﺷﺮﻭﻉ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﻫﺎ ﺍﺯ ﻻﻳﻪ ‪ Application‬ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻭ ﺑﺎ‬ ‫ﺣﺮﮐﺖ ﺑﻪ ﺳﻤﺖ ﭘﺎﻳﻴﻦ‪ ،‬ﺩﺭ ﻫﺮ ﻻﻳﻪ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺍﻧﺠﺎﻡ ﻭ ﺩﺍﺩﻩ ﻫﺎﺋﻲ ﺑﻪ ﺑﺴﺘﻪ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺁﺧﺮﻳﻦ ﻻﻳﻪ )ﻻﻳﻪ ﻓﻴﺰﻳﮑﻲ( ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‪ ،‬ﺩﺍﺩﻩ ﻫﺎ ﺑﻪ ﺳﻴﮕﻨﺎﻟﻬﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ‪ ،‬ﭘﺎﻟﺲ ﻫﺎﺋﻲ ﺍﺯ ﻧﻮﺭ ﻭ ﻳﺎ ﺳﻴﮕﻨﺎﻟﻬﺎﻱ ﺭﺍﺩﻳﻮﺋﻲ‬ ‫‪136‬‬

‫ﺗﺒﺪﻳﻞ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﮐﺎﺑﻞ ﻭ ﻳﺎ ﻫﻮﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﭘﺲ ﺍﺯ ﺩﺭﻳﺎﻓﺖ‬ ‫ﺩﺍﺩﻩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ )ﻣﻌﮑﻮﺱ ﻋﻤﻠﻴﺎﺕ ﺍﺭﺳﺎﻝ( ﺗﻮﺳﻂ ﻫﺮ ﻳﮏ ﺍﺯ‬

‫ﻻﻳﻪ ﻫﺎ ﺍﻧﺠﺎﻡ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ ﺑﺎ ﺭﺳﻴﺪﻥ ﺩﺍﺩﻩ ﺑﻪ ﻻﻳﻪ ‪ Application‬ﻭ ﺑﮑﻤﮏ ﻳﮏ ﺑﺮﻧﺎﻣﻪ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‬ ‫ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﻻﻳﻪ ﻫﺎﻱ ‪OSI‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ ﻣﺪﻝ ‪ OSI‬ﺍﺯ ﻫﻔﺖ ﻻﻳﻪ ﻣﺘﻔﺎﻭﺕ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‬ ‫ﻋﻤﻠﮑﺮﺩ ﻫﺮ ﻻﻳﻪ ﺗﺸﺮﻳﺢ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻻﻳﻪ ﻫﻔﺖ ) ‪ . (Application‬ﺍﻳﻦ ﻻﻳﻪ ﺑﺎ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭ ﻳﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ‬

‫ﮐﺎﺭﺑﺮﺩﻱ ﺍﺭﺗﺒﺎﻁ ﺩﺍﺭﺩ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﮐﺎﺭﺑﺮﺩﻱ ﻣﺘﻔﺎﻭﺕ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺗﺒﻂ ﺑﺎ ﺷﺒﮑﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻣﺜﻼ" ﮐﺎﺭﺑﺮﺍﻥ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ‬ ‫ﻓﺎﻳﻞ ﺧﻮﺍﻧﺪﻥ ﭘﻴﺎﻡ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﻭ ‪ ...‬ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫•‬

‫ﻻﻳﻪ ﺷﺶ ) ‪ . (Presentation‬ﻻﻳﻪ ﻓﻮﻕ ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻻﻳﻪ‬ ‫‪ Application‬ﺍﺧﺬ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﺗﺒﺪﻳﻞ ﺧﻮﺍﻫﺪ ﮐﺮﺩ ﮐﻪ ﺗﻮﺳﻂ ﺳﺎﻳﺮ ﻻﻳﻪ ﻫﺎ‬ ‫ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺎﺷﺪ‪.‬‬

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‫•‬

‫ﻻﻳﻪ ﭘﻨﺞ ) ‪ . (Session‬ﻻﻳﻪ ﻓﻮﻕ ﻣﺴﺌﻮﻝ ﺍﻳﺠﺎﺩ ‪ ،‬ﭘﺸﺘﻴﺒﺎﻧﻲ ﻭ ﺍﺭﺗﺒﺎﻃﺎﺕ ﻣﺮﺑﻮﻃﻪ‬

‫•‬

‫ﻻﻳﻪ ﭼﻬﺎﺭ ) ‪ . (Transport‬ﻻﻳﻪ ﻓﻮﻕ ﻣﺴﺌﻮﻝ ﭘﺸﺘﻴﺒﺎﻧﻲ ﮐﻨﺘﺮﻝ ﺟﺮﻳﺎﻥ ﺩﺍﺩﻩ ﻫﺎ ﻭ‬

‫ﺑﺎ ﺩﺳﺘﮕﺎﻩ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪.‬‬

‫ﻭ ﺑﺮﺭﺳﻲ ﺧﻄﺎﺀ ﻭ ﺑﺎﺯﻳﺎﺑﻲ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪ .‬ﮐﻨﺘﺮﻝ ﺟﺮﻳﺎﻥ‬ ‫ﺩﺍﺩﻩ ﻫﺎ ‪ ،‬ﺑﺪﻳﻦ ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ ﻻﻳﻪ ﻓﻮﻕ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﭼﻨﺪﻳﻦ ﺑﺮﻧﺎﻣﻪ‬

‫ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﻫﺮ ﺑﺮﻧﺎﻣﻪ ﺭﺍ ﺑﻪ ﻳﮏ ‪ stream‬ﺁﻣﺎﺩﻩ ﺗﺒﺪﻳﻞ‬ ‫ﺗﺎ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺷﺒﮑﻪ ﻓﻴﺰﻳﮑﻲ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﺷﻮﻧﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ﺳﻪ ) ‪ . (Network‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ ﺭﻭﺵ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﻫﺎ ﺑﺮﺍﻱ ﺩﺳﺘﮕﺎﻩ ﮔﻴﺮﻧﺪﻩ‬

‫ﺗﻌﻴﻴﻦ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻨﻄﻘﻲ‪ ،‬ﺭﻭﺗﻴﻨﮓ ﻭ ﺁﺩﺭﺱ ﺩﻫﻲ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﺍﻧﺠﺎﻡ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ﺩﻭ ) ‪ .( Data‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻓﻴﺰﻳﮑﻲ ﺑﻪ ﺩﺍﺩﻩ ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﻨﺪ‬

‫ﺷﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻧﻮﻉ ﺷﺒﮑﻪ ﻭ ﻭﺿﻌﻴﺖ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ )‪ (Packet‬ﻧﻴﺰ ﺗﻌﻴﻴﻦ‬ ‫ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ﻳﮏ )‪ . (Physical‬ﻻﻳﻪ ﻓﻮﻕ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﻣﺴﺘﻘﻴﻢ ﺑﺎ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺑﻮﺩﻩ ﻭ‬ ‫ﺧﺼﺎﻳﺺ ﻓﻴﺰﻳﮑﻲ ﺷﺒﮑﻪ ﻧﻈﻴﺮ ‪ :‬ﺍﺗﺼﺎﻻﺕ‪ ،‬ﻭﻟﺘﺎﮊ ﻭ ﺯﻣﺎﻥ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺪﻝ ‪ OSI‬ﺑﺼﻮﺭﺕ ﻳﮏ ﻣﺮﺟﻊ ﺑﻮﺩﻩ ﻭ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﭘﺸﺘﻪ ﺍﻱ ﻳﮏ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﻻﻳﻪ ﺍﺯ‬ ‫ﻣﺪﻝ ﻓﻮﻕ ﺭﺍ ﺗﺮﮐﻴﺐ ﻭ ﺩﺭ ﻳﮏ ﻻﻳﻪ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﭘﺸﺘﻪ ﺍﻱ‬

‫ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﭘﺸﺘﻪ ﺍﻱ‪ ،‬ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺍﺳﺖ ﮐﻪ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻓﻌﺎﻟﻴﺖ ﻧﻤﻮﺩﻩ‬ ‫ﺗﺎ ﺍﻣﮑﺎﻥ ﺍﻧﺠﺎﻡ ﻳﮏ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺹ ﺭﺍ ﺑﺮﺍﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻭ ﻳﺎ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻓﺮﺍﻫﻢ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻧﻤﻮﻧﻪ ﺍﻱ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﭘﺸﺘﻪ ﺍﻱ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﺯ ﭼﻬﺎﺭ ﻻﻳﻪ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻻﻳﻪ ﻳﮏ )‪ . (Interface Network‬ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﻻﻳﻪ ﻫﺎﻱ ‪ Physical‬ﻭ‬ ‫‪ Data‬ﺭﺍ ﺗﺮﮐﻴﺐ ﻭ ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ‬ ‫ﺭﻭﺕ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫•‬

‫ﻻﻳﻪ ﺩﻭ )‪ . (Internet‬ﻻﻳﻪ ﻓﻮﻕ ﻣﺘﻨﺎﻇﺮ ﻻﻳﻪ ‪ Network‬ﺩﺭ ﻣﺪﻝ ‪ OSI‬ﺍﺳﺖ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﺍﻳﻨﺘﺮﻧﺖ )‪ ، (IP‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ‪ ) IP‬ﺷﺎﻣﻞ ﻳﮏ ﻣﺸﺨﺼﻪ ﺷﺒﮑﻪ ﻭ ﻳﮏ‬

‫ﻣﺸﺨﺼﻪ ﻣﻴﺰﺑﺎﻥ ( ‪ ،‬ﺁﺩﺭﺱ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ﺳﻪ )‪ . (Transport‬ﻻﻳﻪ ﻓﻮﻕ ﻣﺘﻨﺎﻇﺮ ﺑﺎ ﻻﻳﻪ ‪ Transport‬ﺩﺭ ﻣﺪﻝ ‪OSI‬‬ ‫ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ‪ )TCP(Trnsport control protocol‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ ﺍﻳﻔﺎﻱ‬ ‫ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‬

‫•‬

‫ﻻﻳﻪ ﭼﻬﺎﺭ )‪ . (Application‬ﻻﻳﻪ ﻓﻮﻕ ﻣﺘﻨﺎﻇﺮ ﺑﺎ ﻻﻳﻪ ﻫﺎﻱ‬ ‫‪ Session,Presentation‬ﻭ ‪ Application‬ﺩﺭ ﻣﺪﻝ ‪ OSI‬ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ‬ ‫ﻫﺎﺋﻲ ﻧﻈﻴﺮ ‪ FTP‬ﻭ ‪ SMTP‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﻧﺤﻮﻩ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺁﻳﺎ ﺗﺎﮐﻨﻮﻥ ﺑﺮﺍﻱ ﺷﻤﺎ ﺍﻳﻦ ﺳﻮﺍﻝ ﻣﻄﺮﺡ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﻧﺤﻮﻩ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﺩﻭ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺍﺳﺖ؟ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺗﺎﺑﻊ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﻫﻤﺎﻧﻨﺪ ﻳﮏ‬ ‫ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﺍﺟﺮﺍﺋﻲ ﺑﻮﺩﻩ ﻭ ﻋﻤﻠﻴﺎﺕ ﻻﺯﻡ ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﺭﺍ ﺑﺮﺍﻱ ﻳﮏ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺷﻨﺎﺋﻲ ﻭ ﺁﻧﺎﻟﻴﺰ ﻓﺮﺁﻳﻨﺪ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙــﻴﻮﺗﺮ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﻳﮏ ﻧﻤﻮﻧﻪ ﻣﺜﺎﻝ ﮐﺎﺭﺑﺮﺩﻱ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﺍﺗﻮﻣﺒﻴﻞ ﺩﺭ ﮐﺎﺭﺧﺎﻧﻪ ﺍﻱ ﺗﻮﻟﻴﺪ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻳﮏ ﻧﻔﺮ ﺗﻤﺎﻣﻲ ﮐﺎﺭﻫﺎ ﺭﺍ ﺍﻧﺠﺎﻡ‬

‫ﻧﺨﻮﺍﻫﺪ ﺩﺍﺩ ‪ .‬ﺗﻮﻟﻴﺪ ﻳﮏ ﺍﺗﻮﻣﺒﻴﻞ ﺑﺮ ﺍﺳﺎﺱ ﻳﮏ ﺧﻂ ﺗﻮﻟﻴﺪ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﻭ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺣﺮﮐﺖ‬ ‫ﺍﺗﻮﻣﺒﻴﻞ ﺩﺭ ﺧﻂ ﺗﻮﻟﻴﺪ ﻫﺮ ﺷﺨﺺ ﺑﺨﺶ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻩ ﻭ ﺯﻣﺎﻧﻲ ﮐﻪ‬ ‫ﺑﻪ ﺍﻧﺘﻬﺎﻱ ﺧﻂ ﺗﻮﻟﻴﺪ ﻣﻲ ﺭﺳﻴﻢ‪ ،‬ﺍﺗﻮﻣﺒﻴﻞ ﻣﻮﺭﺩ ﻧﻈﺮ ﺗﻮﻟﻴﺪ ﻭ ﺁﻣﺎﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺩﺍﺩﻩ ﺍﺭﺳﺎﻟﻲ ﺍﺯ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﻧﻴﺰ ﺻﺪﻕ ﻣﻲ ﮐﻨﺪ‪.‬‬

‫ﻣﺪﻝ ‪ OSI‬ﮐﻪ ﺗﻮﺳﻂ ﮐﻤﻴﺘﻪ ‪ IEEE‬ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﻗﻮﺍﻧﻴﻦ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻭ ﺑﺎ ﭘﻴﺮﻭﻱ ﺍﺯ ﻣﺠﻤﻮﻋﻪ‬ ‫ﺭﻫﻨﻤﻮﺩﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺩﺭ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ ،OSI‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺳﺎﻳﺮ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ) ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﻧﻮﻉ ﮐﺎﻣﭙﻴﻮﺗﺮ ( ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺣﺮﮐﺖ ﺩﺍﺩﻩ ﺑﺎ ﺩﻭ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ ﺩﺭ‬

‫ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﺍﻧﺠﺎﻡ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺳﻤﺖ ﻓﺮﺳﺘﻨﺪﻩ ) ﺑﻪ ﻃﺮﻑ ﭘﺎﺋﻴﻦ (‪ ،‬ﺩﺍﺩﻩ ﻫﺎ ﮐﭙﺴﻮﻟﻪ‬ ‫ﺷﺪﻩ ﻭ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮔﻴﺮﻧﺪﻩ ﺍﺭﺳﺎﻝ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺩﺭ ﺳﻤﺖ ﮔﻴﺮﻧﺪﻩ ) ﺑﻪ ﻃﺮﻑ ﺑﺎﻻ (‪ ،‬ﺩﺍﺩﻩ ﻫﺎ‬

‫ﺍﺯ ﺣﺎﻟﺖ ﮐﭙﺴﻮﻟﻪ ﺧﺎﺭﺝ ﺷﺪﻩ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮔﻴﺮﻧﺪﻩ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪.‬‬

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‫ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ‪ :‬ﺷﮑﻞ ﺯﻳﺮﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫ﺗﻮﺿﻴﺤﺎﺕ ‪:‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺭﺍ ﺩﺍﺭﺩ‪ .‬ﺩﺭ ﻻﻳﻪ‬

‫‪ ، Application‬ﺭﺍﺑﻂ ﮐﺎﺭﺑﺮ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺁﻥ ﮐﺎﺭﺑﺮ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻻﻳﻪ ‪ ، Application‬ﺩﺍﺩﻩ ﺍﺭﺳﺎﻟﻲ ﺑﻪ ﺗﺮﺗﻴﺐ ﻻﻳﻪ ﻫﺎﻱ‬ ‫‪ Presentation‬ﻭ ‪ Session‬ﺭﺍ ﻃﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ ﺍﻱ ﺭﺍ ﺑﻪ ﺩﺍﺩﻩ ﺍﻭﻟﻴﻪ ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻩ ﻭ ﺩﺭ ﻧﻬﺎﻳﺖ ﺩﺍﺩﻩ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ‬

‫‪ Transport‬ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫•‬

‫ﺩﺭ ﻻﻳﻪ ‪ ، Transport‬ﺩﺍﺩﻩ ﺑﻪ ﺑﺨﺶ ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮﻱ ﺗﻘﺴﻴﻢ ﻭ ﻫﺪﺭ ‪ TCP‬ﺑﻪ ﺁﻥ‬ ‫ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺑﻪ ﺩﺍﺩﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ ‪" ، Transport‬ﺳﮕﻤﻨﺖ" ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‬

‫‪ .‬ﻫﺮ ﺳﮕﻤﻨﺖ ﺷﻤﺎﺭﻩ ﮔﺬﺍﺭﻱ ﺷﺪﻩ ﺗﺎ ﺍﻣﮑﺎﻥ ﺑﺎﺯﺳﺎﺯﻱ ﻣﺠﺪﺩ ﺁﻧﺎﻥ ﺩﺭ ﻣﻘﺼﺪ ﻭﺟﻮﺩ‬ ‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ) ﺍﻧﺘﻈﺎﺭ ﺩﺍﺭﻳﻢ ﺩﺍﺩﻩ ﺩﺭﻳﺎﻓﺘﻲ ﺗﻮﺳﻂ ﮔﻴﺮﻧﺪﻩ ﻫﻤﺎﻥ ﺩﺍﺩﻩ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ‬ ‫ﻓﺮﺳﺘﻨﺪﻩ ﺑﺎﺷﺪ(‪.‬‬

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‫ﻫﺮ ﺳﮕﻤﻨﺖ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺩﺭﺱ ﺩﻫﻲ ﺷﺒﮑﻪ )ﻣﻨﻈﻮﺭ ﺁﺩﺭﺱ ﺩﻫﻲ ﻣﻨﻄﻘﻲ‬ ‫ﺍﺳﺖ( ﻭ ﺭﻭﺗﻴﻨﮓ ﻣﻨﺎﺳﺐ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ ‪ Network‬ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﻪ ﺩﺍﺩﻩ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ ‪ ،Network‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﻳﺎ ‪ Packet‬ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﻻﻳﻪ ‪ ،Network‬ﻫﺪﺭ ‪ IP‬ﺧﻮﺩ ﺭﺍ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻩ ﻭ ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﻻﻳﻪ‬

‫‪ DataLink‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﻻﻳﻪ ‪ DataLink‬ﺑﻪ ﺩﺍﺩﻩ ﺋﻲ ﮐﻪ ﻫﻢ ﺍﻳﻨﮏ ﺷﺎﻣﻞ ﻫﺪﺭ ﻻﻳﻪ ﻫﺎﻱ ‪ Transport‬ﻭ‬ ‫‪ Network‬ﺍﺳﺖ‪" ،‬ﻓﺮﻳﻢ" ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭﻳﺎﻓﺘﻲ‪ ،‬ﮐﭙﺴﻮﻟﻪ ﺷﺪﻩ ﻭ ﺩﺭ ﻳﮏ ﻓﺮﻳﻢ ﺑﻪ ﻫﻤﺮﺍﻩ ﺁﺩﺭﺱ ﺳﺨـﺖ‬ ‫ﺍﻓـــــﺰﺍﺭﻱ) ﺁﺩﺭﺱ ‪ ( MAC‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ‬ ‫ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺩﺭ ﻓﺮﻳﻢ ﻓﻮﻕ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ‪) LLC‬ﻧﻮﻉ ﭘﺮﻭﺗﮑﻞ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ‬

‫ﻻﻳﻪ ﻗﺒﻠﻲ ﺯﻣﺎﻧﻲ ﮐﻪ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﻣﻲ ﺭﺳﺪ(‪ ،‬ﻧﻴﺰ ﺍﺿﺎﻓﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺑﺨﺶ‬ ‫ﺍﻧﺘﻬﺎﺋﻲ ﻓﺮﻳﻢ ‪ ،‬ﻓﻴﻠﺪﻱ ﺑﺎ ﻧﺎﻡ ‪ FCS‬ﮐﻪ ﺍﺯ ﮐﻠﻤﺎﺕ ‪Frame Check Sequence‬‬ ‫ﺍﻗﺘﺒﺎﺱ ﺷﺪﻩ ﺍﺳﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﺭﺳﻲ ﺧﻄﺎﺀ ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺑﺎﺷﺪ‪ ،‬ﻓﺮﻳﻢ ﺑﻪ ﺭﻭﺗﺮ‬ ‫ﻭ ﻳﺎ ‪ gateway‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻣﻨﺎﺳﺐ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻘﺮﺍﺭ ﻓﺮﻳﻢ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺑﻪ ﺻﻮﺭﺕ‬ ‫ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺩﻳﺠﻴﺘﺎﻝ ﺗﺒﺪﻳﻞ ﺷﻮﻧﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﻳﮏ ﻓﺮﻳﻢ ﻣﺸﺘﻤﻞ ﺑﺮ ﻣﺠﻤﻮﻋﻪ‬ ‫ﺍﻱ ﺍﺯ ﺻﻔﺮ ﻭ ﻳﮏ ﺍﺳﺖ‪ ،‬ﻻﻳﻪ ‪ Physical‬ﻋﻤﻠﻴﺎﺕ ﮐﭙﺴﻮﻟﻪ ﻧﻤﻮﺩﻥ ﺍﺭﻗﺎﻡ ﻣﻮﺟﻮﺩ ﺩﺭ‬

‫ﻓﺮﻳﻢ ﺑﻪ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺩﻳﺠﻴﺘﺎﻝ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﺩﺭ ﺍﺑﺘﺪﺍﻱ ﻓﺮﻳﻢ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻫﻤﺰﻣﺎﻥ ﺳﺎﺯﻱ )ﻫﻤﺎﻫﻨﮓ ﺷﺪﻥ ﺩﺭﻳﺎﻓﺖ‬

‫ﮐﻨﻨﺪﻩ ﺑﺎ ﻓﺮﺳﺘﻨﺪﻩ (‪ ،‬ﺗﻌﺪﺍﺩ ﺍﻧﺪﮐﻲ ﺻﻔﺮ ﻭ ﻳﮏ ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ‪ :‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫ﺗﻮﺿﻴﺤﺎﺕ ‪:‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﻫﻤﺎﻫﻨﮓ ﮐﺮﺩﻥ ﺧﻮﺩ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﺮﺳﺘﻨﺪﻩ‬

‫ﺩﺭ ﺟﻬﺖ ﺧﻮﺍﻧﺪﻥ ﺳﻴﮕﻨﺎﻝ ﺩﻳﺠﻴﺘﺎﻝ‪ ،‬ﺗﻌﺪﺍﺩ ﻣﺤﺪﻭﺩﻱ ﺍﺯ ﺑﻴﺖ ﻫﺎ ﺭﺍ ﻣﻲ ﺧﻮﺍﻧﺪ‪ .‬ﭘﺲ ﺍﺯ‬ ‫ﺍﺗﻤﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻫﻤﺰﻣﺎﻥ ﺳﺎﺯﻱ ﻭ ﺩﺭﻳﺎﻓﺖ ﺗﻤﺎﻣﻲ ﻓﺮﻳﻢ ﺁﻥ ﺭﺍ ﺑﻪ ﻻﻳﻪ ﺑﺎﻻﺗﺮ )ﻻﻳﻪ‬

‫‪ ،( DataLink‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﻻﻳﻪ ‪ ، DataLink‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻭﺟﻮﺩ ﺧﻄﺎﺀ ) ‪ ( CRC‬ﻭ ﻳﺎ‬ ‫ﻫﻤﺎﻥ ‪ Cyclic Redundancy Check‬ﺭﺍ ﺩﺭ ﺧﺼﻮﺹ ﺍﻃﻼﻋﺎﺕ ﺩﺭﻳﺎﻓﺘﻲ‬ ‫ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﻣﺤﺎﺳﺒﺎﺕ ﻓﻮﻕ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﻭ‬

‫ﻣﺎﺣﺼﻞ ﮐﺎﺭ ﺑﺎ ﻣﻘﺪﺍﺭ ﻣﻮﺟﻮﺩ ﺩﺭ ﻓﻴﻠﺪ ‪ FCS‬ﻣﻘﺎﻳﺴﻪ ﺷﺪﻩ ﻭ ﺑﺮ ﺍﺳﺎﺱ ﺁﻥ ﺗﺸﺨﻴﺺ‬ ‫ﺩﺍﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ ﮐﻪ ﺁﻳﺎ ﻓﺮﻳﻢ ﺩﺭﻳﺎﻓﺘﻲ ﺑﺪﻭﻥ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺍﺳﺖ؟ ﺩﺭ ﺍﺩﺍﻣﻪ‬ ‫ﻻﻳﻪ ‪ ،DataLink‬ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ ﻭ ﻳﺎ ﻫﺪﺭﻱ ﺭﺍ ﮐﻪ ﺗﻮﺳﻂ ﻻﻳﻪ ‪DataLink‬‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺍﺳﺖ ﺭﺍ ﺑﺮﺩﺍﺷﺘﻪ ﻭ ﻣﺎﺑﻘﻲ ﺩﺍﺩﻩ ﺭﺍ ﮐﻪ ﺑﻪ ﺁﻥ‬ ‫‪ Packet‬ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ ﺑﺮﺍﻱ ﻻﻳﻪ ‪ Network‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺩﺭ ﻻﻳﻪ ‪ ، Network‬ﺁﺩﺭﺱ ‪ IP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻣﻘﺎﻳﺴﻪ ﺷﺪﻩ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﻣﻄﺎﺑﻘﺖ ‪ ،‬ﻫﺪﺭ ﻻﻳﻪ ‪ Network‬ﻭ ﻳﺎ‬

‫ﻫﺪﺭ ‪ IP‬ﺍﺯ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺩﺍﺷﺘﻪ ﺷﺪﻩ ﻭ ﻣﺎﺑﻘﻲ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﻻﻳﻪ ﺑﺎﻻﺗﺮ‬ ‫) ﻻﻳﻪ ‪ ،( Transport‬ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻪ ﺩﺍﺩﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ‪ ،‬ﺳﮕﻤﻨﺖ‬

‫ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫•‬

‫ﺳﮕﻤﻨﺖ ﺩﺭ ﻻﻳﻪ ‪ Transport‬ﭘﺮﺩﺍﺯﺵ ﻭ ﻋﻤﻠﻴﺎﺕ ﺑﺎﺯﺳﺎﺯﻱ ﻣﺠﺪﺩ ﺩﺍﺩﻩ ﺩﺭﻳﺎﻓﺘﻲ‪،‬‬ ‫ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺑﺎﺯﺳﺎﺯﻱ ﻣﺠﺪﺩ ﺩﺍﺩﻩ ﺩﺭﻳﺎﻓﺘﻲ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮔﻴﺮﻧﺪﻩ ﺑﻪ‬

‫ﻓﺮﺳﺘﻨﺪﻩ ﺍﻃﻼﻉ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ ﮐﻪ ﻭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺨﺶ ﻫﺎ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻧﻤﻮﺩﻩ ﺍﺳﺖ ﺗﺎ‬ ‫ﺧﻠﻠﻲ ﺩﺭ ﺑﺎﺯﺳﺎﺯﻱ ﻣﺠﺪﺩ ﺩﺍﺩﻩ ﺍﻳﺠﺎﺩ ﻧﮕﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ‪ ACK‬ﺑﺮﺍﻱ‬ ‫ﻓﺮﺳﺘﻨﺪﻩ ) ﺍﻋﻼﻡ ﻭﺿﻌﻴﺖ ﺳﮕﻤﻨﺖ ﺩﺭﻳﺎﻓﺘﻲ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﺮﺳﺘﻨﺪﻩ (‪ ،‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪TCP‬‬ ‫ﺩﺭ ﻣﻘﺎﺑﻞ ‪ UDP‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﺩﺍﺩﻩ ﺩﺭﻳﺎﻓﺘﻲ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ ‪ Application‬ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﺩﺭﮔﻴﺮ ﺟﺰﺋﻴﺎﺕ ﻣﺴﺌﻠﻪ ﻧﺸﺪﻩ ﻭ ﺗﻤﺎﻣﻲ‬ ‫ﻓﺮﺁﻳﻨﺪﻫﺎﻱ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺑﻪ ﺻﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ‬ ‫ﭘﻮﻳﺶ ﻳﮏ ﭘﻮﺭﺕ ﻓﺮﺁﻳﻨﺪﻱ ﺍﺳﺖ ﮐﻪ ﻣﻬﺎﺟﻤﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﻗﺎﺩﺭ ﺑﻪ ﺗﺸﺨﻴﺺ‬

‫ﻭﺿﻌﻴﺖ ﻳﮏ ﭘﻮﺭﺕ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﻴﺴﺘﻢ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﻬﺎﺣﻤﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺍﺑﺰﺍﺭﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺑﻪ ﭘﻮﺭﺕ ﻫﺎﻱ ‪ TCP‬ﻭ ‪ UDP‬ﻧﻤﻮﺩﻩ ﻭ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫ﭘﺎﺳﺦ ﺩﺭﻳﺎﻓﺘﻲ ﻗﺎﺩﺭ ﺑﻪ ﺗﺸﺨﻴﺺ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ ﮐﻪ ﮐﺪﺍﻡ ﭘﻮﺭﺕ ﻫﺎ ﺩﺭ ﺣﺎﻝ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﮐﺪﺍﻡ ﭘﻮﺭﺕ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﮔﺮﺩﺩ ﻭ ﺍﺻﻄﻼﺣﺎ" ﺁﻧﺎﻥ ﺑﺎﺯ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﻣﻬﺎﺟﻤﺎﻥ ﺩﺭ ﺍﺩﺍﻣﻪ ﻭ ﺑﺮ ﺍﺳﺎﺱ ﺍﻃﻼﻋﺎﺕ ﺩﺭﻳﺎﻓﺘﻲ‪ ،‬ﺑﺮ ﺭﻭﻱ ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺎﺯ ﻣﺘﻤﺮﮐﺰ ﺷﺪﻩ ﻭ‬ ‫ﺣﻤﻼﺕ ﺧﻮﺩ ﺭﺍ ﺑﺮ ﺍﺳﺎﺱ ﺁﻧﺎﻥ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻋﻤﻠﮑﺮﺩ ﻣﻬﺎﺟﻤﺎﻥ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ‬

‫ﻣﺸﺎﺑﻪ ﺳﺎﺭﻗﺎﻧﻲ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﻴﻞ ﺑﻪ ﺍﻫﺪﺍﻑ ﻣﺨﺮﺏ ﺧﻮﺩ ) ﺳﺮﻗﺖ (‪ ،‬ﺩﺭﺍﺑﺘﺪﺍ‬ ‫ﻭﺿﻌﻴﺖ ﺩﺭﺏ ﻫﺎ ﻭ ﭘﻨﺠﺮﻩ ﻫﺎﻱ ﻣﻨﺎﺯﻝ ﺭﺍ ﺑﺮﺭﺳﻲ ﻧﻤﻮﺩﻩ ﺗﺎ ﭘﺲ ﺍﺯ ﺁﮔﺎﻫﻲ ﺍﺯ ﻭﺿﻌﻴﺖ ﺁﻧﺎﻥ‬ ‫) ﺑﺎﺯ ﺑﻮﺩﻥ ﻭ ﻳﺎ ﻗﻔﻞ ﺑﻮﺩﻥ (‪ ،‬ﺳﺮﻗﺖ ﺧﻮﺩ ﺭﺍ ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫‪ ( TCP (Transmission Control Protocol‬ﻭ) ‪User Datagram ) UDP‬‬ ‫‪ ،Protocol‬ﺩﻭ ﭘﺮﻭﺗـﮑﻞ ﻣﻬﻢ ‪ TCP/IP‬ﻣﻲ ﺑﺎﺷـﻨﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗــﮑﻞ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺩﺍﺭﺍﻱ ﺷﻤﺎﺭﻩ ﭘﻮﺭﺗﻲ ﺑﻴﻦ ﺻﻔﺮ ﺗﺎ ‪ ٦٥،٥٣٥‬ﺑﺎﺷﻨﺪ ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﺎ ﺩﺍﺭﺍﻱ ﺑﻴﺶ ﺍﺯ‬ ‫‪ ٦٥،٠٠٠‬ﺩﺭﺏ ﻣﻲ ﺑﺎﺷﻴﻢ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺎﺯ ﺑﻮﺩﻥ ﻭ ﻳﺎ ﺑﺴﺘﻦ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ‬

‫ﺗﻌﻴﻴﻦ ﺗﮑﻠﻴﻒ ﻧﻤﻮﺩ ) ﺷﺒﮑﻪ ﺍﻱ ﺑﺎ ﺑﻴﺶ ﺍﺯ ‪ ٦٥،٠٠٠‬ﺩﺭﺏ! (‪ .‬ﺍﺯ ‪ ١٠٢٤‬ﭘﻮﺭﺕ ﺍﻭﻝ ‪TCP‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻱ ﻧﻈﻴﺮ ‪ FTP,HTTP,SMTP‬ﻭ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ ‪ ) .‬ﭘﻮﺭﺕ ﻫﺎﻱ ﺧﻮﺵ ﻧﺎﻡ (‪ .‬ﺑﻪ ﺑﺮﺧﻲ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺎﻻﻱ ‪ ١٠٢٣‬ﻧﻴﺰ ﺳﺮﻭﻳﺲ‬ ‫ﻫﺎﻱ ﺷﻨﺎﺧﺘﻪ ﺷﺪﻩ ﺍﻱ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﻭﻟﻲ ﺍﻏﻠﺐ ﺍﻳﻦ ﭘﻮﺭﺕ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺗﻮﺳﻂ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺩﺭ ﺩﺳﺘﺮﺱ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﺩﺭ ﺍﺑﺘﺪﺍ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻫﺪﻑ ﻭ ﺑﺮ ﺭﻭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﻧﻤﻮﺩﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﺘﺎﻳﺞ ﺑﺪﺳﺖ ﺁﻣﺪﻩ‪ ،‬ﻗﺎﺩﺭ‬

‫ﺑﻪ ﺗﺸﺨﻴﺺ ﻭﺿﻌﻴﺖ ﻳﮏ ﭘﻮﺭﺕ ﻣﻲ ﺑﺎﺷﻨﺪ )ﺑﺎﺯ ﺑﻮﺩﻥ ﻭ ﻳﺎ ﺑﺴﺘﻪ ﺑﻮﺩﻥ ﻳﮏ ﭘﻮﺭﺕ(‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻳﻨﮕﻮﻧﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺑﺎ ﺍﻫﺪﺍﻑ ﻣﺨﺮﺏ ﺑﻪ ﺧﺪﻣﺖ ﮔﺮﻓﺘﻪ ﺷﻮﻧﺪ‪ ،‬ﻣﻬﺎﺟﻤﺎﻥ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺗﺸﺨﻴﺺ ﻭﺿﻌﻴﺖ ﭘﻮﺭﺕ ﻫﺎ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﻴﺴﺘﻢ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺁﻧﺎﻥ ﻣﻲ‬ ‫ﺗﻮﺍﻧﻨﺪ ﺗﻬﺎﺟﻢ ﺧﻮﺩ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﻧﻤﺎﻳﻨﺪ ﮐﻪ ﻧﺎﺷﻨﺎﺧﺘﻪ ﺑﺎﻗﻲ ﻣﺎﻧﺪﻩ ﻭ ﺍﻣﮑﺎﻥ‬

‫ﺗﺸﺨﻴﺺ ﺁﻧﺎﻥ ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺍﻣﻨﻴﺘﻲ ﻧﺼﺐ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﮕﻮﻧﻪ ﺍﻱ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﻮﻧﺪ ﮐﻪ ﺩﺭ ﺻﻮﺭﺕ ﺗﺸﺨﻴﺺ ﺍﻳﺠﺎﺩ ﻳﮏ‬

‫ﺍﺭﺗﺒﺎﻁ ﻭ ﭘﻮﻳﺶ ﻣﺴﺘﻤﺮ ﻭ ﺑﺪﻭﻥ ﻭﻗﻔﻪ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﺩﺭ ﻳﮏ ﻣﺤﺪﻭﺩﻩ ﺯﻣﺎﻧﻲ‬ ‫ﺧﺎﺹ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﻫﺸﺪﺍﺭﻫﺎﻱ ﻻﺯﻡ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺪﻳﺮﻳﺖ ﺳﻴﺴﺘﻢ ﻗﺮﺍﺭ ﺩﻫﻨﺪ‪.‬‬ ‫ﻣﻬﺎﺟﻤﺎﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻋﻤﺪﻩ "ﺁﺷﮑﺎﺭ" ﻭ ﻳﺎ " ﻣﺨﻔﻲ" ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﭘﻮﻳﺶ ﺁﺷﮑﺎﺭ ‪ ،‬ﻣﻬﺎﺟﻤﺎﻥ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻌﺪﺍﺩ ﭘﻮﺭﺕ ﻫﺎﺋﻲ ﮐﻪ ﻗﺼﺪ‬

‫ﺑﺮﺭﺳﻲ ﺁﻧﺎﻥ ﺭﺍ ﺩﺍﺭﻧﺪ‪ ،‬ﺩﺍﺭﺍﻱ ﻣﺤﺪﻭﺩﻳﺖ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ ) ﺍﻣﮑﺎﻥ ﭘﻮﻳﺶ ﺗﻤﺎﻣﻲ ‪٦٥،٥٣٥‬‬ ‫ﭘﻮﺭﺕ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ (‪ .‬ﺩﺭ ﭘﻮﻳﺶ ﻣﺨﻔﻲ‪ ،‬ﻣﻬﺎﺟﻤﺎﻥ ﺍﺯ ﺭﻭﺵ ﻫﺎﺋﻲ ﻧﻈﻴﺮ " ﭘﻮﻳﺶ ﮐﻨﺪ "‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩﻩ ﺗﺎ ﺍﺣﺘﻤﺎﻝ ﺷﻨﺎﺳﺎﺋﻲ ﺁﻧﺎﻥ ﮐﺎﻫﺶ ﻳﺎﺑﺪ‪ .‬ﺑﺎ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﺩﺭ ﻳﮏ ﻣﺤﺪﻭﺩﻩ‬ ‫ﺯﻣﺎﻧﻲ ﺑﻴﺸﺘﺮ ‪ ،‬ﺍﺣﺘﻤﺎﻝ ﺗﺸﺨﻴﺺ ﺁﻧﺎﻥ ﺗﻮﺳﻂ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺍﻣـــﻨﻴﺘﻲ ﻧﺼﺐ ﺷﺪﻩ ﺩﺭ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﺎﻫﺶ ﭘﻴﺪﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﺑﺎ ﺗﻨﻈﻴﻢ ﻓﻼﮒ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ‪ TCP‬ﻭ ﻳﺎ ﺍﺭﺳﺎﻝ ﺍﻧﻮﺍﻉ ﻣﺘﻔﺎﻭﺗﻲ‬ ‫ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ‪ TCP‬ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻧﺘﺎﻳﺞ ﻣﺘﻔﺎﻭﺕ ﻭ ﺗﺸﺨﻴﺺ ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺎﺯ ﺑﺮ‬ ‫ﺍﺳﺎﺱ ﺭﻭﺵ ﻫﺎﻱ ﻣﺨﺘﻠﻔﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﻳﮏ ﭘﻮﻳﺶ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ SYN‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﺘﺎﻳﺞ‬ ‫ﺑﺪﺳﺖ ﺁﻣﺪﻩ ﺍﻋﻼﻡ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﮐﺪﺍﻡ ﭘﻮﺭﺕ ﺑﺎﺯ ﻭ ﻳﺎ ﮐﺪﺍﻡ ﭘﻮﺭﺕ ﺑﺴﺘﻪ ﺍﺳﺖ ﻭ ﻳﺎ ﺩﺭ ﻳﮏ‬

‫ﭘﻮﻳﺶ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ FIN‬ﺑﺮ ﺍﺳﺎﺱ ﭘﺎﺳﺨﻲ ﮐﻪ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺴﺘﻪ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﭘﻮﺭﺕ‬ ‫ﻫﺎﻱ ﺑﺎﺯ ﭘﺎﺳﺨﻲ ﺭﺍ ﺍﺭﺳﺎﻝ ﻧﺨﻮﺍﻫﻨﺪ ﮐﺮﺩ( ﻭﺿﻌﻴﺖ ﻳﮏ ﭘﻮﺭﺕ ﺭﺍ ﺗﺸﺨﻴﺺ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫‪146‬‬

‫ﻧﺤﻮﻩ ﭘﻴﺸﮕﻴﺮﻱ ﻭ ﺣﻔﺎﻇﺖ‬

‫ﻣﺪﻳﺮﺍﻥ ﺷﺒﮑﻪ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻣﺘﻨﻮﻋﻲ ﮐﻪ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﺍﺯ‬

‫ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺗﻮﺳﻂ ﻣﻬﺎﺟﻤﺎﻥ ﺁﮔﺎﻩ ﮔﺮﺩﻧﺪ ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﺗﻤﺎﻣﻲ ﭘﻮﻳﺶ‬ ‫ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ SYN‬ﺭﺍ ﺛﺒﺖ ﺗﺎ ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﻣﮑﺎﻥ ﺑﺮﺭﺳﻲ ﺩﻗﻴﻖ ﺁﻧﺎﻥ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪.‬‬ ‫)ﺗﺸﺨﻴﺺ ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ‪ SYN‬ﺑﻪ ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺎﺯ ﻭ ﻳﺎ ﺑﺴﺘﻪ(‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﺍﻳﻤﻦ ﺳﺎﺯﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻲ ﺗﻮﺍﻥ ﺧﻮﺩ ﺭﺍﺳﺎ" ﺍﻗﺪﺍﻡ ﺑﻪ‬

‫ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﻧﻤﻮﺩ ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﺋﻲ ﻧﻈﻴﺮ ‪ NMap‬ﻣﻲ ﺗﻮﺍﻥ ﻣﺤﺪﻭﺩﻩ ﺍﻱ ﺍﺯ‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻭ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﺮﺭﺳﻲ ﻧﻤﻮﺩ ) ﺷﺒﻴﻪ ﺳﺎﺯﻱ ﻳﮏ ﺗﻬﺎﺟﻢ (‪ .‬ﭘﺲ‬

‫ﺍﺯ ﻣﺸﺨﺺ ﺷﺪﻥ ﻭﺿﻌﻴﺖ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻗﺪﺍﻣﺎﺕ ﻻﺯﻡ ﺣﻔﺎﻇﺘﻲ ﺩﺭ ﺍﻳﻦ‬ ‫ﺧﺼﻮﺹ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﻪ ﻭﺟﻮﺩ ) ﺑﺎﺯ ﺑﻮﺩﻥ ( ﻳﮏ ﭘﻮﺭﺕ ﻧﻴﺎﺯ ﻧﻤﻲ ﺑﺎﺷﺪ‪،‬‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺁﻧﺎﻥ ﺭﺍ ﻏﻴﺮ ﻓﻌﺎﻝ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺿﺮﻭﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﭘﻮﺭﺕ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺗﻬﺪﻳﺪﺍﺗﻲ ﮐﻪ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﺯ ﺟﺎﻧﺐ ﺁﻥ ﭘﻮﺭﺕ ﻣﺘﻮﺟﻪ ﺳﻴﺴﺘﻢ ﻭ‬ ‫ﻳﺎ ﺷﺒﮑﻪ ﮔﺮﺩﺩ ﺭﺍ ﺍﻧﺠﺎﻡ ﻭ ﺑﺎ ﻧﺼﺐ ‪ patch‬ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﺁﻧﺎﻥ ﺍﻣﮑﺎﻥ ﺳﻮﺀ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﭘﻮﺭﺕ ﻫﺎﻱ ﺑﺎﺯ ﺭﺍ ﮐﺎﻫﺶ ﺩﺍﺩ‪.‬‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻮﻳﺶ ﭘﻮﺭﺕ ﻫﺎ ﻭ ﺁﮔﺎﻫﻲ ﺍﺯ ﻭﺿﻌﻴﺖ ﭘﻮﺭﺕ ﻫﺎﻱ ‪ TCP‬ﻭ ‪ UDP‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ‪:‬‬ ‫•‬ ‫•‬ ‫•‬

‫‪ ) Nmap‬ﻳﺎ ‪( Network Mapper‬‬ ‫‪FoundStone Vision‬‬ ‫‪FoundStone FPort‬‬

‫•‬

‫‪FoundStone ScanLine‬‬

‫•‬

‫‪Found Stone SuperScan‬‬

‫•‬

‫‪ ) FireWalls.com Port Scan‬ﺑﺮﺭﺳﻲ ‪ online‬ﻭﺿﻌﻴﺖ ﭘﻮﺭﺕ ﻫﺎ (‬

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‫ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﭘﻮﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺭ ﻭﻳﻨﺪﻭﺯ‬ ‫ﻭﻳﻨﺪﻭﺯ ﺍﺯ ﻳﮏ ﺯﻳﺮﺳﺎﺧﺖ ﺟﺎﻣﻊ ﻭ ﭘﻴﻮﺳﺘﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺎﻣﻴﻦ ﻃﻴﻒ ﻭﺳﻴﻌﻲ ﺍﺯ ﻧﻴﺎﺯﻫﺎ ﻭ‬ ‫ﺧﻮﺍﺳﺘﻪ ﻫﺎﻱ ﭘﻴﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﻭﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﺣﺮﻓﻪ ﺍﻱ ﻓﻦ ﺁﻭﺭﻱ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺩﺭ ﺯﻳﺮﺳﺎﺧﺖ ﻓﻮﻕ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﺩ ﺗﺎ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺍﻃﻼﻋﺎﺕ ﻗﺎﺩﺭ‬

‫ﺑﻪ ﺩﺳﺘﻴﺎﺑﻲ‪ ،‬ﺁﻧﺎﻟﻴﺰ ﻭ ﺍﺷﺘﺮﺍﮎ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﺳﺎﺩﮔﻲ ﻭ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻﺋﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻣﺤﺼﻮﻻﺕ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺷﺮﮐﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺍﺯ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﭘﻮﺭﺕ ﻭ ﭘﺮﻭﺗﮑﻞ ﺷﺒﮑﻪ‬ ‫ﺍﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺳﻴﺴﺘﻤﻬﺎﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﻤﻦ ﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺯ ﻓﺎﻳﺮﻭﺍﻝ ﻫﺎﻱ ﺧﺎﺻﻲ ﻭ ﻳﺎ‬

‫ﻓﻴﻠﺘﺮﻫﺎﻱ ‪ IPSec‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺮﺧﻲ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﻭ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺗﻮﺳﻂ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﻼﮎ ﺷﺪﻩ ﻭ ﺑﺪﻧﺒﺎﻝ ﺁﻥ ﺍﻣﮑﺎﻥ ﭘﺎﺳﺨﮕﻮﺋﻲ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺑﻪ‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﺠﺎﺯ‪ ،‬ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ) ﻋﺪﻡ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻭ‬

‫ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺗﻮﺳﻂ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ(‪.‬‬ ‫ﺑﺮﺧﻲ ﺗﻌﺎﺭﻳﻒ ﺍﻭﻟﻴﻪ‬ ‫•‬

‫ﺳﻴﺴﺘﻢ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﻳﻨﺪﻭﺯ ‪ ،‬ﺍﺯ ﻣﺤﺼﻮﻻﺕ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ﺧﺎﻧﻮﺍﺩﻩ ﻧﺴﺨﻪ ﻫﺎﻱ‬

‫ﻭﻳﻨﺪﻭﺯ ‪ ،٢٠٠٣‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، Exchange 2000‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪SQL‬‬ ‫‪ ، Server 2000‬ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﻣﺤﺼﻮﻻﺕ ﻓﻮﻕ ﺍﺯ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ‬ ‫ﻋﻨﺎﺻﺮ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺳﻴﺴﺘﻢ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﻧﺪ ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺳﻴﺴﺘﻢ ﺩﺭ‬

‫ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻭ ﺗﻮﺳﻂ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺍﺟﺮﺍﺀ ﺷﺪﻩ ﻭ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺑﺮ ﺍﺳﺎﺱ ﺗﺤﻘﻖ‬ ‫ﺷﺮﺍﻳﻄﻲ ﺧﺎﺹ ‪ ،‬ﻓﻌﺎﻟﻴﺖ ﺧﻮﺩ ﺭﺍ ﺁﻏﺎﺯ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻫﺮ ﺳﺮﻭﻳﺲ ﺳﻴﺴﺘﻢ ﺩﺍﺭﺍﻱ ﻳﮏ‬ ‫ﻧﺎﻡ ﺧﻮﺩﻣﺎﻧﻲ ﻭ ﻳﮏ ﻧﺎﻡ ﺳﺮﻭﻳﺲ ﺍﺳﺖ‪ .‬ﻧﺎﻡ ﺧﻮﺩﻣﺎﻧﻲ‪ ،‬ﻧﺎﻣﻲ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺍﺑﺰﺍﺭﻫﺎﻱ‬

‫ﻣﺪﻳﺮﻳﺘﻲ ﮔﺮﺍﻓﻴﮑﻲ ﻧﻈﻴﺮ ) ‪، Microsoft Management Console (MMC‬‬ ‫ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﻧﺎﻡ ﺳﺮﻭﻳﺲ‪ ،‬ﻧﺎﻣﻲ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻪ ﻫﻤﺮﺍﻩ ﺍﺑﺰﺍﺭﻫﺎﻱ ﺧﻂ‬

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‫ﺩﺳﺘﻮﺭ ﻭ ﻳﺎ ﺯﺑﺎﻥ ﻫﺎﻱ ﺍﺳﮑﺮﻳﭙﺖ ﻧﻮﻳﺴﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺮ ﺳﺮﻭﻳﺲ ﺳﻴﺴﺘﻢ‬

‫ﻣﻤﮑﻦ ﺍﺳﺖ ﻳﮏ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﺳﺮﻭﻳﺲ ﺷﺒﮑﻪ ﺍﻱ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ ، Application‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺳﻄﺢ ﺑﺎﻻﻱ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﮐﻪ ﺍﺯ ﻳﮏ‬

‫ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﭘﺮﻭﺗﮑﻞ ﻭ ﭘﻮﺭﺕ ‪ TCP/IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ HTTP .‬ﻭ ‪SMTP‬‬ ‫ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎ ‪ ،‬ﺩﺭ ﻳﮏ ﺳﻄﺢ ﭘﺎﺋﻴﻦ ﺗﺮ ﻧﺴﺒﺖ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ Application‬ﮐﺎﺭ‬

‫ﻣﻲ ﮐﻨﻨﺪ ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ TCP/IP‬ﻓﺮﻣﺖ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻩ‬ ‫ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ) .‬ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺷﺎﻣﻞ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺩﻳﮕﺮﻱ ﻧﻈﻴﺮ ‪ UDP ، TCP‬ﻭ ‪ ICMP‬ﺍﺳﺖ(‪.‬‬

‫•‬

‫ﭘﻮﺭﺕ ‪ .‬ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺳﻴﺴﺘﻢ ﺑﺎ ﮔﻮﺵ ﺩﺍﺩﻥ ﺑﻪ ﭘﻮﺭﺕ ﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﺗﺸﺨﻴﺺ ﺗﺮﺍﻓﻴﮏ‬ ‫ﻭﺭﻭﺩﻱ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺟﺪﻭﻝ ﺯﻳﺮ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﭘﻮﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺭ ﻣﺤﺼﻮﻻﺕ ﺍﺻﻠﻲ ﻭﻳﻨﺪﻭﺯ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬ ‫‪Application ProtocolPort‬‬ ‫‪protocol‬‬ ‫‪GRE (IP‬‬ ‫‪GRE‬‬ ‫‪n/a‬‬ ‫)‪protocol 47‬‬ ‫‪IPSec ESP (IP ESP‬‬ ‫‪n/a‬‬ ‫)‪protocol 50‬‬ ‫‪IPSec AH (IP AH‬‬ ‫‪n/a‬‬ ‫)‪protocol 51‬‬ ‫‪Echo‬‬ ‫‪TCP‬‬ ‫‪7‬‬ ‫‪7‬‬

‫‪UDP‬‬

‫‪Echo‬‬

‫‪9‬‬

‫‪TCP‬‬

‫‪Discard‬‬

‫‪149‬‬

‫‪System‬‬ ‫‪Service Name‬‬ ‫‪Routing and‬‬ ‫‪Remote Access‬‬ ‫‪Routing and‬‬ ‫‪Remote Access‬‬ ‫‪Routing and‬‬ ‫‪Remote Access‬‬ ‫‪Simple TCP/IP‬‬ ‫‪Services‬‬ ‫‪Simple TCP/IP‬‬ ‫‪Services‬‬ ‫‪Simple TCP/IP‬‬ ‫‪Services‬‬

Simple TCP/IP Discard Services Simple TCP/IP Daytime Services Simple TCP/IP Daytime Services Simple TCP/IP Quotd Services Simple TCP/IP Quotd Services Simple TCP/IP Chargen Services Simple TCP/IP Chargen Services FTP Publishing FTP default Service data FTP Publishing FTP control Service Application Layer FTP control Gateway Service Telnet Telnet Simple Mail SMTP Transfer Protocol Simple Mail SMTP Transfer Protocol Exchange Server SMTP Exchange Server SMTP Windows WINS Internet Name Replication Service Windows WINS Internet Name Replication Service DNS Server DNS 150

UDP

9

TCP

13

UDP

13

TCP

17

UDP

17

TCP

19

UDP

19

TCP

20

TCP

21

TCP

21

TCP TCP

23 25

UDP

25

TCP UDP TCP

25 25 42

UDP

42

TCP

53

DNS Server DNS Internet DNS Connection Firewall/Internet Connection Sharing DHCP Server DHCP Server Internet DHCP Server Connection Firewall/Internet Connection Sharing Trivial FTP TFTP Daemon Service Windows Media HTTP Services World Wide Web HTTP Publishing Service SharePoint Portal HTTP Server Kerberos Key Kerberos Distribution Center Kerberos Key Kerberos Distribution Center Microsoft X.400 Exchange MTA Stacks Microsoft POP3 POP3 Service Exchange Server POP3 Network News NNTP 151

UDP TCP

53 53

UDP UDP

67 67

UDP

69

TCP

80

TCP

80

TCP

80

TCP

88

UDP

88

TCP

102

TCP

110

TCP TCP

110 119

Transfer Protocol Windows Time NTP Windows Time SNTP Message RPC Queuing Remote RPC Procedure Call Exchange Server RPC Certificate RPC Services Cluster Service RPC Distributed File RPC System Distributed Link RPC Tracking Distributed RPC Transaction Coordinator Event Log RPC Fax Service RPC File Replication RPC Local Security RPC Authority Remote Storage RPC Notification Remote Storage RPC Server Systems RPC Management Server 2.0 Terminal RPC Services Licensing Terminal RPC 152

UDP UDP TCP

123 123 135

TCP

135

TCP TCP

135 135

TCP TCP

135 135

TCP

135

TCP

135

TCP TCP TCP TCP

135 135 135 135

TCP

135

TCP

135

TCP

135

TCP

135

TCP

135

Services Session Directory Computer NetBIOS Browser Name Resolution Server NetBIOS Name Resolution Windows NetBIOS Internet Name Name Service Resolution Net Logon NetBIOS Name Resolution Systems NetBIOS Management Name Server 2.0 Resolution Computer NetBIOS Browser Datagram Service Messenger NetBIOS Datagram Service Server NetBIOS Datagram Service Net Logon NetBIOS Datagram Service Distributed File NetBIOS System Datagram Service Systems NetBIOS Management Datagram 153

UDP

137

UDP

137

UDP

137

UDP

137

UDP

137

UDP

138

UDP

138

UDP

138

UDP

138

UDP

138

UDP

138

Server 2.0 Service License Logging NetBIOS Datagram Service Service Computer NetBIOS Browser Session Service NetBIOS Fax Service Session Service Performance NetBIOS Logs and Alerts Session Service Print Spooler NetBIOS Session Service Server NetBIOS Session Service Net Logon NetBIOS Session Service Remote NetBIOS Procedure Call Session Locator Service Distributed File NetBIOS System Session Service Systems NetBIOS Management Session Server 2.0 Service License Logging NetBIOS Service Session Service 154

UDP

138

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

TCP

139

Exchange Server IMAP TCP SNMP Service SNMP UDP SNMP Trap SNMP Traps UDP Service Outbound Local Security LDAP Server TCP Authority Local Security LDAP Server UDP Authority Distributed File LDAP Server TCP System Distributed File LDAP Server UDP System HTTP SSL HTTPS TCP World Wide Web HTTPS TCP Publishing Service SharePoint Portal HTTPS TCP Server Fax Service SMB TCP Print Spooler SMB TCP Server SMB TCP Remote SMB TCP Procedure Call Locator Distributed File SMB TCP System License Logging SMB TCP Service Net Logon SMB TCP Local Security IPSec ISAKMP UDP Authority TCP/IP Print LPD TCP Server File Server for File Server for TCP 155

143 161 162 389 389 389 389 443 443 443 445 445 445 445 445 445 445 500 515 548

Macintosh Macintosh Windows Media RTSP TCP Services Network News NNTP over TCP Transfer Protocol SSL Remote RPC over TCP Procedure Call HTTP Exchange Server RPC over TCP HTTP Local Security LDAP SSL TCP Authority Local Security LDAP SSL UDP Authority Exchange Server IMAP over TCP SSL Exchange Server POP3 over TCP SSL Microsoft MOMTCP Operations Encrypted Manager 2000 Microsoft SQL SQL over TCP TCP Server MSSQL$UDDI SQL over TCP TCP Microsoft SQL SQL Probe UDP Server MSSQL$UDDI SQL Probe UDP Internet Legacy UDP Authentication RADIUS Service Internet Legacy UDP Authentication RADIUS Service Routing and L2TP UDP Remote Access 156

554 563 593 593 636 636 993 995 1270 1433 1433 1434 1434 1645 1646 1701

Routing and Remote Access Windows Media Services Windows Media Services Message Queuing Message Queuing Internet Authentication Service Internet Authentication Service SSDP Discovery Service Message Queuing Message Queuing Message Queuing Message Queuing SQL Server: Downlevel OLAP Client Support SQL Server: Downlevel OLAP Client Support Windows Media Services

PPTP

TCP

1723

MMS

TCP

1755

MMS

UDP

1755

MSMQ

TCP

1801

MSMQ

UDP

1801

RADIUS UDP Authentication

1812

RADIUS Accounting

UDP

1813

SSDP

UDP

1900

MSMQ-DCs

TCP

2101

MSMQ-RPC

TCP

2103

MSMQ-RPC

TCP

2105

MSMQ-Mgmt TCP

2107

OLAP Services TCP 7.0

2393

OLAP Services TCP 7.0

2394

MS Theater

2460

157

UDP

DHCP Server SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SMS Remote Control Agent SQL Analysis Server UPNP Device Host SSDP Discovery Service Local Security Authority Local Security Authority Cluster Service NetMeeting

MADCAP UDP SMS Remote TCP Control (control) SMS Remote UDP Control (control) SMS Remote TCP Control (data) SMS Remote UDP Control (data) SMS Remote TCP Chat SMS Remote UPD Chat SMS Remote TCP File Transfer SMS Remote UDP File Transfer SQL Analysis TCP Services UPNP TCP

2535 2701

SSDP event notification Global Catalog Server Global Catalog Server Cluster Services Terminal

TCP

2869

TCP

3268

TCP

3269

UDP

3343

TCP

3389

158

2701 2702 2702 2703 2703 2704 2704 2725 2869

Remote Desktop Sharing Terminal Services Message Queuing Remote Installation Local Security Authority SSDP Discovery Service

Services Terminal Services MSMQ-Ping

TCP

3389

UDP

3527

BINL

UDP

4011

NAT-T

UDP

4500

SSDP legacy TCP event notification Windows Media RTP UDP Services Windows Media RTCP UDP Services ASP.NET State ASP.Net TCP Service Session State Microsoft MOM-Clear TCP Operations Manager 2000

5000

‫ ﺳﺎﻳﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ‬: ‫ﻣﻨﺒﻊ‬

159

5004 5005 42424 51515

‫ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬ ‫‪ TCP/IP‬ﭘﺮﻭﺗﮑﻞ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮒ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﭘﺮﻭﺗﮑﻞ‬

‫ﻓﻮﻕ ﮐﻨﺪ ﻭ ﻣﺴﺘﻠﺰﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻨﺎﺑﻊ ﺯﻳﺎﺩﻱ ﺍﺳﺖ‪ ،‬ﻭﻟﻲ ﺑﺪﻟﻴﻞ ﻣﺰﺍﻳﺎﻱ ﺑﺎﻻﻱ ﺁﻥ ﻧﻈﻴﺮ‪ :‬ﻗﺎﺑﻠﻴﺖ‬ ‫ﺭﻭﺗﻴﻨﮓ‪ ،‬ﺣﻤﺎﻳﺖ ﺩﺭ ﺍﻏﻠﺐ ﭘﻼﺕ ﻓﻮﺭﻡ ﻫﺎ ﻭ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ ﻫﻤﭽﻨﺎﻥ ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺣﺮﻑ ﺍﻭﻝ ﺭﺍ ﻣﻲ ﺯﻧﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺩﺭ ﺍﺧﺘﻴﺎﺭ‬

‫ﺩﺍﺷﺘﻦ ﻭﻳﻨﺪﻭﺯ ﻭ ﭘﺲ ﺍﺯ ﺍﺗﺼﺎﻝ ﺑﻪ ﺷﺒﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺑﺮﺍﺣﺘﻲ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﮐﺎﺭﺑﺮﺍﻥ ﺩﻳﮕﺮ‬

‫ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ ﮐﻪ ﺍﺯ ﻣﮑﻴﻨﺘﺎﺵ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﺪ‬ ‫ﺍﻣﺮﻭﺯﻩ ﮐﻤﺘﺮ ﻣﺤﻴﻄﻲ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﻳﺎﻓﺖ ﮐﻪ ﻧﻴﺎﺯﺑﻪ ﺩﺍﻧﺶ ﮐﺎﻓﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ‪ TCP/IP‬ﻧﺒﺎﺷﺪ‪.‬‬

‫ﺣﺘﻲ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺷﺒﮑﻪ ﺍﻱ ﻧﺎﻭﻝ ﮐﻪ ﺳﺎﻟﻴﺎﻥ ﻣﺘﻤﺎﺩﻱ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ IPX/SPX‬ﺑﺮﺍﻱ‬

‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﺮﺩ‪ ،‬ﺩﺭﻧﺴــﺨﻪ ﺷﻤﺎﺭﻩ ﭘﻨﺞ ﺧﻮﺩ ﺑﻪ ﺿـــﺮﻭﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ‬ ‫ﻓﻮﻕ ﻭﺍﻗﻒ ﻭ ﻧﺴﺨﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺭﺍﺋﻪ ﻧﻤﻮﺩ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ‪ ) ARPAnet‬ﻧﺴﺨﻪ ﻗﺒﻠﻲ ﺍﻳﻨﺘﺮﻧﺖ (‬ ‫ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﻭﺯﺍﺭﺕ ﺩﻓﺎﻉ ﺍﻣﺮﻳﮑﺎ ﺑﺎ ﻫﻤﮑﺎﺭﻱ ﺑﺮﺧﻲ ﺍﺯ ﺩﺍﻧﺸﮕﺎﻫﻬﺎ ﺍﻗﺪﺍﻡ ﺑﻪ ﻃﺮﺍﺣﻲ ﻳﮏ‬

‫ﺳﻴﺴﺘﻢ ﺟﻬﺎﻧﻲ ﻧﻤﻮﺩ ﮐﻪ ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎ ﻭ ﻇﺮﻓﻴﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺣﺘﻲ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ‬ ‫ﺟﻨﮓ ﻫﺴﺘﻪ ﺍﻱ ﺑﺎﺷﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻓﻮﻕ‪ TCP/IP ،‬ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪ‪.‬‬ ‫ﺍﺟﺰﺍﻱ ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺩﻳﮕﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺭ ﻻﻳﻪ‬

‫ﻣﺮﺑﻮﻃﻪ‪ ،‬ﻭﻇﺎﻳﻒ ﺧﻮﺩ ﺭﺍ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ‬ ‫‪ Transport‬ﻭ ‪ Network‬ﺩﺍﺭﺍﻱ ﺍﻫﻤﻴﺖ ﺑﺴﺰﺍﺋﻲ ﺑﻮﺩﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﺁﻧﻬﺎ‬ ‫ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫‪160‬‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ ‪ Network‬ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ‪ ،(Transmission Control Protocol)TCP‬ﻣﻬﻤﺘﺮﻳﻦ ﻭﻇﻴﻔﻪ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﺻﻄﻼﺣﺎ"‬

‫‪ Connection-oriented‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺍﻳﺠﺎﺩ ﻳﮏ ﺍﺭﺗﺒﺎﻁ‬ ‫ﻣﺠﺎﺯﻱ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺑﻌﺪ ﺍﺯ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ‬

‫ﻫﺎﺋﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ‪ ،‬ﺍﻣﮑﺎﻧﺎﺕ ﺑﻴﺸﺘﺮﻱ ﺭﺍﺑﻪ ﻣﻨﻈﻮﺭ ﮐﻨﺘﺮﻝ ﺧﻄﺎﻫﺎﻱ ﺍﺣﺘﻤﺎﻟﻲ ﺩﺭ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻩ ﻭﻟﻲ ﺑﺪﻟﻴﻞ ﺍﻓﺰﺍﻳﺶ ﺑﺎﺭ ﻋﻤﻠﻴﺎﺗﻲ ﺳﻴﺴﺘﻢ ﮐﺎﺭﺍﺋﻲ ﺁﻧﺎﻥ ﮐﺎﻫﺶ‬ ‫ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪TCP‬ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﻗﺎﺑﻞ ﺍﻃﻤﻴﻨﺎﻥ ﻧﻴﺰ ﻳﺎﺩ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻭ ﮐﺴﺐ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺍﺯ ﮔﻴﺮﻧﺪﻩ ﺍﻃﻼﻋﺎﺕ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ ﺍﺭﺳﺎﻝ ﺗﻮﺳﻂ ﻓﺮﺳﺘﻨﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﺴﺘﻪ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﺪﺭﺳﺘﻲ ﺩﺭﺍﺧﺘﻴﺎﺭ ﻓﺮﺳﺘﻨﺪﻩ ﻗﺮﺍﺭ ﻧﮕﻴﺮﻧﺪ‪ ،‬ﻓﺮﺳﺘﻨﺪﻩ ﻣﺠﺪﺩﺍ" ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ . (Datagram Protocol User(UDP‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻧﻈﻴﺮ ﭘﺮﻭﺗﮑﻞ‬ ‫‪ TCP‬ﺩﺭ ﻻﻳﻪ " ﺣﻤﻞ " ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ UDP .‬ﺑﺮ ﺧﻼﻑ ﭘﺮﻭﺗﮑﻞ ‪TCP‬‬ ‫ﺑﺼﻮﺭﺕ " ﺑﺪﻭﻥ ﺍﺗﺼﺎﻝ " ﺍﺳﺖ‪ .‬ﺑﺪﻳﻬﻲ ﺍﺳﺖ ﮐﻪ ﺳﺮﻋﺖ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻧﺴﺒﺖ ﺑﻪ‬ ‫‪ TCP‬ﺳﺮﻳﻌﺘﺮ ﺑﻮﺩﻩ ﻭﻟﻲ ﺍﺯ ﺑﻌﺪ ﮐﻨﺘﺮﻝ ﺧﻄﺎﺀ ﺗﻈﻤﻴﻨﺎﺕ ﻻﺯﻡ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬

‫ﺑﻬﺘﺮﻳﻦ ﺟﺎﻳﮕﺎﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﺍﺳﺖ ﮐﻪ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻳﮏ ﺳﻄﺢ ﺑﺎﻻ ﺍﺯ ﺍﻃﻤﻴﻨﺎﻥ‪ ،‬ﻧﻴﺎﺯ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ . (Internet Protocol(IP‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺩﺭ ﻻﻳﻪ ﺷﺒﮑﻪ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ‬ ‫ﮐﺮﺩﻩ ﻭ ﻣﻬﻤﺘﺮﻳﻦ ﻣﺴﺌﻮﻟﻴﺖ ﺁﻥ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺎﺻﺪ‬ ‫ﺩﺭﺳﺖ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﻣﻨﻄﻘﻲ‪،‬‬ ‫ﻋﻤﻠﻴﺎﺕ ﺭﻭﺗﻴﻨﮓ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ ‪ Application‬ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺻﺮﻓﺎ" ﺑﻪ ﺳﻪ ﭘﺮﻭﺗﮑﻞ ‪ UDP ،TCP‬ﻭ ‪ IP‬ﻣﺤﺪﻭﺩ ﻧﺸﺪﻩ ﻭ ﺩﺭ ﺳﻄﺢ‬ ‫ﻻﻳﻪ ‪ Application‬ﺩﺍﺭﺍﻱ ﻣﺠﻤﻮﻋﻪ ﮔﺴﺘﺮﺩﻩ ﺍﻱ ﺍﺯ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ‬

‫ﻓﻮﻗﺒﻪ ﻋﻨﻮﺍﻥ ﻣﺠﻤﻮﻋﻪ ﺍﺑﺰﺍﺭﻫﺎﺋﻲ ﺑﺮﺍﻱ ﻣﺸﺎﻫﺪﻩ‪ ،‬ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﻭ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﻭ ﺳﺎﻳﺮ‬ ‫ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﻧﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﺑﻪ ﻣﻌﺮﻓﻲ ﺑﺮﺧﻲ ﺍﺯ ﺍﻳﻦ ﭘﺮﻭﺗﮑﻞ ﻫﺎ‬ ‫ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ‪ . (File Transfer Protocol(FTP‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺮﺍﻱ ﺗﮑﺜﻴﺮ ﻓﺎﻳﻞ‬ ‫ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﻴﭙﻴﻮﺗﺮ ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻭﻳﻨﺪﻭﺯ‬ ‫ﺩﺍﺭﺍﻱ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺧﻂ ﺩﺳﺘﻮﺭﻱ ﺑﻮﺩﻩ ﮐﻬﺒﻪ ﻋﻨﻮﺍﻥ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ‬

‫ﮐﺮﺩﻩ ﻭ ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺩﺭﻳﺎﻓﺖ ﻓﺎﻳﻞ ﻫﺎ ﺭﺍ ﺍﺯ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ FTP‬ﻓﺮﺍﻫﻢ‬ ‫ﻣﻲ ﮐﻨﺪ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ‪ .(Protocol Simple Network Management(SNMP‬ﺍﺯ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﺁﻣﺎﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻳﮏ ﺳﻴﺴﺘﻢ‬

‫ﻣﺪﻳﺮﻳﺘﻲ‪ ،‬ﺩﺭﺧﻮﺍﺳﺖ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻳﮏ ﺁﮊﺍﻧﺲ ‪ SNMP‬ﻣﻄﺮﺡ ﻭ ﻣﺎﺣﺼﻞ ﻋﻤﻠﻴﺎﺕ‬ ‫ﮐﺎﺭ ﺩﺭ ﻳﮏ ‪ MIB-Management Information Base‬ﺫﺧﻴﺮﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ MIB .‬ﻳﮏ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺩﻩ ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﺩﺭ ﺧﻮﺩ ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﻧﻤﺎﻳﺪ‪) .‬ﻣﺜﻼ" ﭼﻪ ﻣﻴﺰﺍﻥ ﻓﻀﺎ ﻱ ﻫﺎﺭﺩ‬ ‫ﺩﻳﺴﮏ ﻭﺟﻮﺩ ﺩﺍﺭﺩ(‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ‪ . TelNet‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺎﺩﺭ ﺑﻪ ‪ ، log on‬ﺍﺟﺮﺍﻱ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﻣﺸﺎﻫﺪﻩ ﻓﺎﻳﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻭﻳﻨﺪﻭﺯ ﺩﺍﺭﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺟﻬﺖ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﭘﺘﺎﻧﺴﻴﻞ ﻓﻮﻕ ﺍﺳﺖ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ .( simple Mail Transfer Protocol (SMTP‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ .( HyperText Transfer Protocol (HTTP‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‬

‫ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﺸﻬﻮﺭﺗﺮﻳﻦ ﭘﺮﻭﺗﮑﻞ ﺩﺭ ﺍﻳﻦ ﮔﺮﻭﻩ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﺁﻥ ﺑﺮﺍﻱ ﺭﺍﻳﺞ ﺗﺮﻳﻦ ﺳﺮﻭﻳﺲ ﺍﻳﻨﺘﺮﻧﺖ‬ ‫ﻳﻌﻨﻲ ﻭﺏ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﻣﺒﺎﺩﻟﻪ‬

‫ﻓﺎﻳﻞ ﻫﺎ ﺑﺎ ﻓﺮﻣﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ )ﻣﺘﻦ‪ ،‬ﺗﺼﺎﻭﻳﺮ‪،‬ﮔﺮﺍﻓﻴﮑﻲ‪ ،‬ﺻﺪﺍ‪ ،‬ﻭﻳﺪﺋﻮ ﻭ‪ (...‬ﺧﻮﺍﻫﻨﺪ‬ ‫ﺑﻮﺩ‪ .‬ﺑﺮﺍﻱ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺍﺳﺘﻨﺎﺩ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻣﻲ ﺑﺎﻳﺴﺖ‪ ،‬ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺍﺯ‬

‫ﻃﺮﻳﻖ ﻧﺼﺐ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻓﻌﺎﻝ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﺑﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ‪ .(Protocol Network News Transfer (NNTP‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ‬ ‫ﻓﻮﻕ ﺑﺮﺍﻱ ﻣﺪﻳﺮﻳﺖ ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﺭﺳﺎﻟﻲ ﺑﺮﺍﻱ ﮔﺮﻭﻩ ﻫﺎﻱ ﺧﺒﺮﻱ ﺧﺼﻮﺻﻲ ﻭ ﻋﻤﻮﻣﻲ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺍﻱ ﻋﻤﻠﻴﺎﺗﻲ ﻧﻤﻮﺩﻥ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫‪NNTP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺪﻳﺮﻳﺖ ﻣﺤﻞ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﺭﺳﺎﻟﻲ ﻧﺼﺐ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﻭ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﻣﻮﺳﻮﻡ ﺑﻪ ‪NewsReader‬‬

‫ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬ ‫ﻣﺪﻝ ﺁﺩﺭﺱ ﺩﻫﻲ ‪IP‬‬

‫ﻋﻼﻭﻩ ﺑﺮ ﺟﺎﻳﮕﺎﻩ ﭘﺮﻭﺗﮑﻞ ﻫﺎ‪ ،‬ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻋﻨﺎﺻﺮ ﻣﻬﻢ ﺩﺭ ﺯﻳﺮﺳﺎﺧﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬

‫‪ TCP/IP‬ﻣﺪﻝ ﺁﺩﺭﺱ ﺩﻫﻲ ‪ IP‬ﺍﺳﺖ‪ .‬ﻣﺪﻝ ﺍﻧﺘﺨﺎﺑﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺑﻮﺟﻮﺩ‬ ‫ﺁﻭﺭﺩ ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﺑﺪﺭﺳﺘﻲ ﺑﻪ ﻣﻘﺼﺪ ﺧﻮﺍﻫﻨﺪ ﺭﺳﻴﺪ‪.‬‬ ‫ﻧﺴﺨﻪ ﺷﻤﺎﺭﻩ ﭼﻬﺎﺭ ‪ ) IP‬ﻧﺴﺨﻪ ﻓﻌﻠﻲ ( ﺍﺯ ‪ ٣٢‬ﺑﻴﺖ ﺑﺮﺍﻱ ﺁﺩﺭﺱ ﺩﻫﻲ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﮐﻪ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺗﺴﻬﻴﻞ ﺩﺭ ﺍﻣﺮ ﻧﻤﺎﻳﺶ ﺑﺼﻮﺭﺕ ﭼﻬﺎﺭ ﻋﺪﺩ ﺻﺤﻴﺢ ) ﻣﺒﻨﺎﻱ ﺩﻩ ( ﮐﻪ ﺑﻴﻦ ﺁﻧﻬﺎ ﻧﻘﻄﻪ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪.‬‬

‫‪163‬‬

‫ﻧﺤﻮﻩ ﺍﺧﺘﺼﺎﺹ ‪IP‬‬

‫ﻧﺤﻮﻩ ﺍﺧﺘﺼﺎﺹ ‪ IP‬ﺑﻪ ﻋﻨﺎﺻﺮ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ TCP/IP‬ﻳﮑﻲ ﺍﺯ ﻣﻮﺍﺭﺩ‬ ‫ﺑﺴﻴﺎﺭ ﻣﻬﻢ ﺍﺳﺖ‪ .‬ﺍﺧﺘﺼﺎﺹ ‪ IP‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺼﻮﺭﺕ ﺩﺳﺘﻲ ﻭ ﺗﻮﺳﻂ ﻣﺪﻳﺮﻳﺖ ﺷﺒﮑﻪ‬

‫ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﻭ ﻳﺎ ﺍﻧﺠﺎﻡ ﺭﺳﺎﻟﺖ ﻓﻮﻕ ﺑﺮ ﻋﻬﺪﻩ ﻋﻨﺎﺻﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻧﻈﻴﺮ‬

‫‪ DHCP‬ﻭ ﻳﺎ ‪ NAT‬ﮔﺬﺍﺷﺘﻪ ﮔﺮﺩﺩ‬ ‫‪Subnetting‬‬ ‫ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺧﺘﺼﺎﺹ ‪ IP‬ﻣﺴﺌﻠﻪ ‪ Subnetting‬ﺍﺳﺖ ‪ .‬ﻣﺴﺌﻠﻪ‬ ‫ﻓﻮﻕ ﺑﻪ ﻋﻨﻮﺍﻥ ﻫﻨﺮ ﻭ ﻋﻠﻤﻲ ﺍﺳﺖ ﮐﻪ ﻣﺎﺣﺼﻞ ﺁﻥ ﺗﻘﺴﻴﻢ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺷﺒﮑﻪ‬

‫ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮ )‪ (Subnet‬ﺍﺯ ﻃﺮﻳﻖ ﺑﺨﺪﻣﺖ ﮔﺮﻓﺘﻦ ‪ ۳۲‬ﺑﻴﺖ ﺑﺎ ﻧﺎﻡ ‪Subnet mask‬‬

‫ﺑﻮﺩﻩ ﮐﻪ ﺑﻨﻮﻋﻲ ﻣﺸﺨﺼﻪ )‪ (ID‬ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﮐﺎﻟﺒﺪ ﺷﮑﺎﻓﻲ ﺁﺩﺭﺱ ﻫﺎﻱ ‪IP‬‬ ‫ﻫﺮ ﺩﺳﺘﮕﺎﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ TCP/IP‬ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺍﺳﺖ‪.‬‬

‫ﺁﺩﺭﺱ ﻓﻮﻕ ‪ IP‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻣﻄﺎﺑﻖ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬

‫‪219.27.61.137‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺁﺳﺎﻥ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ ، IP‬ﻧﺤﻮﻩ ﻧﻤﺎ ﻳﺶ ﺁﻧﻬﺎ ﺑﺼﻮﺭﺕ ﺩﺳﻴﻤﺎﻝ‬ ‫) ﻣﺒﻨﺎﻱ ﺩﻫﺪﻫﻲ ( ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﭼﻬﺎﺭ ﻋﺪﺩ ﮐﻪ ﺗﻮﺳﻂ ﻧﻘﻄﻪ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﺟﺪﺍ ﻣﻲ ﮔﺮﺩﻧﺪ‪،‬‬ ‫ﺍﺳﺖ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﺍﻋﺪﺍﺩ ﻓﻮﻕ ﺭﺍ ‪ octet‬ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺯ‬ ‫ﻣﺒﻨﺎﻱ ﺩﻭ ) ﺑﺎﻳﻨﺮﻱ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻓﺮﻣﺖ ﺑﺎﻳﻨﺮﻱ ﺁﺩﺭﺱ ‪ IP‬ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺑﺼﻮﺭﺕ ﺯﻳﺮ‬

‫ﺍﺳﺖ‪:‬‬

‫‪11011000.00011011.00111101.10001001‬‬ ‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﻫﺮ ‪ IP‬ﺍﺯ ‪ ٣٢‬ﺑﻴﺖ ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‬

‫ﻣﻲ ﺗﻮﺍﻥ ﺣﺪﺍﮐﺜﺮ ‪ ٤,٢٩٤,٩٦٧,٢٩٦‬ﺁﺩﺭﺱ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺭﺍ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ) ‪.( ٢٣٢‬‬ ‫‪164‬‬

‫ﻣﺜﻼ" ﺁﺩﺭﺱ ‪ ٢٥٥,٢٥٥,٢٥٥,٢٥٥‬ﺑﺮﺍﻱ ‪ ) Broadcast‬ﺍﻧﺘﺸﺎﺭ ﻋﺎﻡ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻧﻤﺎﻳﺶ ﻳﮏ ‪ IP‬ﺑﺼﻮﺭﺕ ﭼﻬﺎﺭ ﻋﺪﺩ ) ‪ (Octet‬ﺻﺮﻓﺎ" ﺑﺮﺍﻱ ﺭﺍﺣﺘﻲ ﮐﺎﺭ ﻧﺒﻮﺩﻩ ﻭ ﺍﺯ ﺁﻧﺎﻥ‬ ‫ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ " ﮐﻼﺱ ﻫﺎﻱ ‪ " IP‬ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻫﺮ ‪ Octet‬ﺑﻪ ﺩﻭ ﺑﺨﺶ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﺩ‪ :‬ﺷﺒﮑﻪ )‪ (Net‬ﻭ ﻣﻴﺰﺑﺎﻥ )‪.(Host‬‬

‫ﺍﻭﻟﻴﻦ ‪ octet‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﺁﻥ ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺷﺒﮑﻪ ﺍﻱ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺑﻪ ﺁﻥ ﺗﻌﻠﻖ ﺩﺍﺭﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﻪ ﺑﺨﺶ ﺩﻳﮕﺮ ‪ ،octet‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺁﺩﺭﺱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‬

‫ﭘﻨﺞ ﮐﻼﺱ ﻣﺘﻔﺎﻭﺕ ‪ IP‬ﺑﻬﻤﺮﺍﻩ ﺑﺮﺧﻲ ﺁﺩﺭﺱ ﻫﺎﻱ ﺧﺎﺹ‪ ،‬ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫‪ . Default Network‬ﺁﺩﺭﺱ ‪ ، ٠,٠,٠,٠ IP‬ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﭘﻴﺶ ﻓﺮﺽ ﺩﺭ ﻧﻈﺮ‬ ‫ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﻣﻮﺍﺭﺩﻳﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﺍﺯ ﺁﺩﺭﺱ ﺧﻮﺩ‬

‫ﺁﮔﺎﻫﻲ ﻧﺪﺍﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺗﺎ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﻧﻈﻴﺮ ‪ DHCP‬ﺍﻋﻼﻡ ﻧﻤﺎﻳﺪ ﺑﺮﺍﻱ ﻭﻱ‬ ‫ﺁﺩﺭﺳﻲ ﺭﺍ ﺗﺨﺼﻴﺺ ﺩﻫﺪ‪.‬‬

‫•‬

‫ﮐﻼﺱ ‪ . A‬ﮐﻼﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺴﻴﺎﺭ ﺑﺰﺭﮒ ﻧﻈﻴﺮ ﻳﮏ ﺷﺮﮐﺖ ﺑﻴﻦ ﺍﻟﻤﻠﻠﻲ‬ ‫ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺁﺩﺭﺱ ﻫﺎﺋﻲ ﮐﻪ ﺍﻭﻟﻴﻦ ‪ octet‬ﺁﻧﻬﺎ ‪ ١‬ﺗﺎ ‪ ١٢٦‬ﺑﺎﺷﺪ‪ ،‬ﮐﻼﺱ‬

‫‪ A‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﺯ ﺳﻪ ‪ octet‬ﺩﻳﮕﺮﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﻴﺰﺑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻣﺠﻤﻮﻉ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ ‪ ، A‬ﻣﻌﺎﺩﻝ ‪ ١٢٦‬ﻭ‬ ‫ﻫﺮ ﻳﮏ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ‪ ١٦,٧٧٧,٢١٤‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪.‬‬

‫) ﻋﺪﺩ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﺻﻞ ‪ ٢٢٤ - ٢‬ﺑﺪﺳﺖ ﺁﻣﺪﻩ ﺍﺳﺖ ( ‪.‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﻌﺪﺍﺩ ﺗﻤﺎﻡ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ ‪ A‬ﻣﻌﺎﺩﻝ ‪ (٢٣١) ٢,١٤٧,٤٨٣,٦٤٨‬ﺍﺳﺖ‪.‬‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ ‪ ، A‬ﺑﻴﺖ ﺑﺎ ﺍﺭﺯﺵ ﺑﺎﻻ ﺩﺭ ﺍﻭﻟﻴﻦ ‪ octet‬ﻫﻤﻮﺍﺭﻩ ﻣﻘﺪﺍﺭ ﺻﻔﺮ‬ ‫ﺭﺍ ﺩﺍﺭﺩ‪.‬‬ ‫)‪Host (Node‬‬

‫‪NET‬‬ ‫‪115.‬‬

‫‪24.53.107‬‬

‫‪165‬‬

‫•‬

‫‪ . LoopBack‬ﺁﺩﺭﺱ ‪ ١٢٧,٠,٠,١ IP‬ﺑﺮﺍﻱ ‪ LoopBack‬ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ‬

‫ﺍﺳﺖ ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﺍﺯ ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﻳﮏ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮐﻨﺪ‪ ).‬ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﭘﻴﺎﻡ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺑﺎﺷﺪ( ﺁﺩﺭﺱ ﻓﻮﻕ ﺍﻏﻠﺐ ﺑﺮﺍﻱ‬ ‫ﺗﺴﺖ ﻭ ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫•‬

‫ﮐﻼﺱ ‪ . B‬ﮐﻼﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺘﻮﺳﻂ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ ).‬ﻣﺜﻼ" ﻳﮏ‬ ‫ﺩﺍﻧﺸﮕﺎﻩ ﺑﺰﺭﮒ ( ﺁﺩﺭﺱ ﻫﺎﺋﻲ ﮐﻪ ﺍﻭﻟﻴﻦ ‪ octet‬ﺁﻧﻬﺎ ‪ ١٢٨‬ﺗﺎ ‪ ١٩١‬ﺑﺎﺷﺪ‪ ،‬ﮐﻼﺱ ‪B‬‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﮐﻼﺱ ﻓﻮﻕ ﺍﺯ ﺩﻭﻣﻴﻦ ‪ octet‬ﻫﻢ ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺩﻭ ‪ octet‬ﺩﻳﮕﺮ ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ‪ (٢١٤ ) ١٦,٣٨٤‬ﺷﺒﮑﻪ ﺍﺯ ﻧﻮﻉ ﮐﻼﺱ ‪B‬‬

‫ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ .‬ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ) ﻫﺮ ﺷﺒﮑﻪ ( ﻣﻌﺎﺩﻝ‬ ‫‪ ( ٢ ١٦ - ٢) ٦٥,٥٣٤‬ﺍﺳﺖ ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﻌﺪﺍﺩ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﮐﻼﺱ ‪ B‬ﻣﻌﺎﺩﻝ ‪ (٢٣٠) ١,٠٧٣,٧٤١,٨٢٤‬ﺍﺳﺖ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ ‪ ،B‬ﺍﻭﻟﻴﻦ ﻭ‬ ‫ﺩﻭﻣﻴﻦ ﺑﻴﺖ ﺩﺭ ﺍﻭﻟﻴﻦ ‪ octet‬ﺑﻪ ﺗﺮﺗﻴﺐ ﻣﻘﺪﺍﺭ ﻳﮏ ﻭ ﺻﻔﺮ ﺭﺍ ﺩﺍﺭﺍ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪NET‬‬ ‫•‬

‫)‪Host (Node‬‬

‫‪53.107‬‬ ‫‪145.24.‬‬ ‫ﮐﻼﺱ ‪ . C‬ﮐﻼﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮏ ﺗﺎ ﻣﺘﻮﺳﻂ ﺩﺭ ﻧﻈﺮﮔﺮﻓﺘﻪ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺁﺩﺭﺱ ﻫﺎﺋﻲ ﮐﻪ ﺍﻭﻟﻴﻦ ‪ octet‬ﺁﻧﻬﺎ ‪ ١٩٢‬ﺗﺎ ‪ ٢٢٣‬ﺑﺎﺷﺪ‪ ،‬ﮐﻼﺱ ) ‪( C‬‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﮐﻼﺱ ﻓﻮﻕ ﺍﺯ ﺩﻭﻣﻴﻦ ﻭ ﺳﻮﻣﻴﻦ ‪ octet‬ﻫﻢ ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﮐﺮﺩﻥ‬ ‫ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺁﺧﺮﻳﻦ ‪ octet‬ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ‪( ٢ ٢١ ) ٢,٠٩٧,١٥٢‬‬

‫ﺷﺒﮑﻪ ﮐﻼﺱ ‪ C‬ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ) ﻫﺮ‬ ‫ﺷﺒﮑﻪ ( ﻣﻌﺎﺩﻝ ‪ ( ٢ ٨ - ٢) ٢٥٤‬ﺍﺳﺖ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﻌﺪﺍﺩ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺩﺭ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ ‪ C‬ﻣﻌﺎﺩﻝ ‪ ( ٢٢٩ ) ٥٣٦,٨٧٠,٩١٢‬ﺍﺳﺖ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻼﺱ‬

‫‪166‬‬

‫‪ ، C‬ﺍﻭﻟﻴﻦ ‪ ،‬ﺩﻭﻣﻴﻦ ﻭ ﺳﻮﻣﻴﻦ ﺑﻴﺖ ﺩﺭ ﺍﻭﻟﻴﻦ ‪ octet‬ﺑﻪ ﺗﺮﺗﻴﺐ ﻣﻘﺪﺍﺭ ﻳﮏ ‪ ،‬ﻳﮏ‬ ‫ﻭ ﺻﻔﺮ ﺭﺍ ﺩﺍﺭﺍ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫‪NET‬‬ ‫•‬

‫)‪Host(Node‬‬

‫‪107‬‬ ‫‪195.24.53.‬‬ ‫ﮐﻼﺱ ‪ . D‬ﺍﺯ ﮐﻼﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ‪ multicasts‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ‬

‫ﻳﮏ ﮔﺮﻩ ) ﻣﻴﺰﺑﺎﻥ( ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﻳﮏ ﮔﺮﻭﻩ ﺧﺎﺹ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪.‬‬ ‫ﺗﻤﺎﻡ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﮔﺮﻭﻩ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ‬ ‫ﮐﺮﺩ‪ ) .‬ﻣﺜﻼ" ﻳﮏ ﺭﻭﺗﺮ ﺳﻴﺴﮑﻮ ﺁﺧﺮﻳﻦ ﻭﺿﻌﻴﺖ ﺑﻬﻨﮕﺎﻡ ﺷﺪﻩ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﺳﺎﻳﺮ‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ ( ﮐﻼﺱ ﻓﻮﻕ ﻧﺴﺒﺖ ﺑﻪ ﺳﻪ ﮐﻼﺱ ﻗﺒﻠﻲ ﺩﺍﺭﺍﻱ‬ ‫ﺳﺎﺧﺘﺎﺭﻱ ﮐﺎﻣﻼ" ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪ .‬ﺍﻭﻟﻴﻦ ‪ ،‬ﺩﻭﻣﻴﻦ ‪ ،‬ﺳﻮﻣﻴﻦ ﻭ ﭼﻬﺎﺭﻣﻴﻦ ﺑﻴﺖ ﺑﻪ ﺗﺮﺗﻴﺐ‬ ‫ﺩﺍﺭﺍﻱ ﻣﻘﺎﺩﻳﺮ ﻳﮏ‪ ،‬ﻳﮏ‪ ،‬ﻳﮏ ﻭ ﺻﻔﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ٢٨.‬ﺑﻴﺖ ﺑﺎﻗﻴﻤﺎﻧﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ‬

‫ﻧﻤﻮﺩﻥ ﮔﺮﻭﻫﻬﺎﺋﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻮﺩﻩ ﮐﻪ ﭘﻴﺎﻡ ‪ Multicast‬ﺑﺮﺍﻱ ﺁﻧﺎﻥ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﮐﻼﺱ ﻓﻮﻕ ﻗﺎﺩﺭ ﺑﻪ ﺁﺩﺭﺳﻲ ﺩﻫﻲ ‪ ( ٢٢٦) ٢٦٨,٤٣٥,٤٥٦‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺖ‪.‬‬ ‫‪NET‬‬ ‫•‬

‫)‪Host(Node‬‬

‫‪24.53.107‬‬ ‫‪224.‬‬ ‫ﮐﻼﺱ ‪ . E‬ﺍﺯ ﮐﻼﺱ ﻓﻮﻕ ﺑﺮﺍﻱ ﻣﻮﺍﺭﺩ ﺗﺠﺮﺑﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﮐﻼﺱ ﻓﻮﻕ ﻧﺴﺒﺖ‬ ‫ﺑﻪ ﺳﻪ ﮐﻼﺱ ﺍﻭﻟﻴﻪ ﺩﺍﺭﺍﻱ ﺳﺎﺧﺘﺎﺭﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪ .‬ﺍﻭﻟﻴﻦ‪ ،‬ﺩﻭﻣﻴﻦ‪ ،‬ﺳﻮﻣﻴﻦ ﻭ‬ ‫ﭼﻬﺎﺭﻣﻴﻦ ﺑﻴﺖ ﺑﻪ ﺗﺮﺗﻴﺐ ﺩﺍﺭﺍﻱ ﻣﻘﺎﺩﻳﺮ ﻳﮏ‪ ،‬ﻳﮏ‪ ،‬ﻳﮏ ﻭ ﻳﮏ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ٢٨ .‬ﺑﻴﺖ‬ ‫ﺑﺎﻗﻴﻤﺎﻧﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﮔﺮﻭﻫﻬﺎﺋﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻮﺩﻩ ﮐﻪ ﭘﻴﺎﻡ‬

‫‪ Multicast‬ﺑﺮﺍﻱ ﺁﻧﺎﻥ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﮐﻼﺱ ﻓﻮﻕ ﻗﺎﺩﺭ ﺑﻪ ﺁﺩﺭﺳﻲ ﺩﻫﻲ‬ ‫‪ ( ٢٢٦) ٢٦٨,٤٣٥,٤٥٦‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺖ‬ ‫‪NET‬‬

‫)‪Host(Node‬‬

‫‪240.‬‬

‫‪24.53.107‬‬

‫‪167‬‬

‫•‬

‫‪ . BroadCast‬ﭘﻴﺎﻡ ﻫﺎﺋﻲ ﺑﺎ ﺁﺩﺭﺳﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ‪ ،‬ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﭘﻴﺎﻡ ﻫﺎ ﻫﻤﻮﺍﺭﻩ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ﺯﻳﺮ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪:‬‬

‫•‬

‫‪255.255.255.255‬‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ﺭﺯﻭ ﺷﺪﻩ ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺯﻳﺮﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﺧﺼﻮﺻﻲ )ﺍﻳﻨﺘﺮﺍﻧﺖ ( ﺭﺯﻭ ﺷﺪﻩ ﺍﻧﺪ‪:‬‬

‫‪10.x.x.x‬‬ ‫ ‪172.16.x.x‬‬‫‪172.31.x.x‬‬ ‫‪192.168.x.x‬‬ ‫‪ IP‬ﻧﺴﺨﻪ ﺷﺶ ‪ .‬ﻧﺴﺨﻪ ﻓﻮﻕ ﺑﺮﺧﻼﻑ ﻧﺴﺨﻪ ﻓﻌﻠﻲ ﮐﻪ ﺍﺯ ‪ ٣٢‬ﺑﻴﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺩﺭﺱ ﺩﻫﻲ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﺍﺯ ‪ ١٢٨‬ﺑﻴﺖ ﺑﺮﺍﻱ ﺁﺩﺭﺱ ﺩﻫﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﺪ‪ .‬ﻫﺮ ﺷﺎﻧﺰﺩﻩ ﺑﻴﺖ‬

‫ﺑﺼﻮﺭﺕ ﻣﺒﻨﺎﻱ ﺷﺎﻧﺰﺩﻩ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪: .‬‬ ‫ﺧﻼﺻﻪ ‪:‬‬

‫‪2b63:1478:1ac5:37ef:4e8c:75df:14cd:93f2‬‬

‫‪Class‬‬

‫‪1st Octet‬‬ ‫‪Net ID‬‬

‫‪2nd Octet‬‬

‫‪3rd Octet‬‬

‫‪4th Octet‬‬ ‫‪Host ID‬‬

‫‪A‬‬ ‫‪Host ID‬‬

‫‪Net ID‬‬ ‫‪B‬‬ ‫‪Net ID‬‬ ‫‪C‬‬ ‫‪Network‬‬ ‫‪Type‬‬ ‫‪Class A‬‬

‫‪001.x.x.x to 126.x.x.x‬‬

‫‪Class B‬‬

‫‪128.1.x.x to 191.254.x.x‬‬

‫‪Class C‬‬ ‫‪Class D‬‬ ‫‪Class E‬‬

‫‪Normal‬‬ ‫‪Comments‬‬ ‫‪Netmask‬‬ ‫‪For very large networks 255.0.0.0‬‬ ‫‪For medium size‬‬ ‫‪255.255.0.0‬‬ ‫‪networks‬‬

‫‪Address Range‬‬

‫‪192.0.1.x to‬‬ ‫‪223.255.254.x‬‬ ‫‪224.x.x.x to‬‬ ‫‪239.255.255.255‬‬ ‫‪240.x.x.x to‬‬ ‫‪247.255.255.255‬‬

‫‪Host ID‬‬

‫‪255.255.255.0‬‬

‫‪168‬‬

‫‪For small networks‬‬ ‫‪Used to support‬‬ ‫‪multicasting‬‬

‫ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﺍﻭﻝ (‬ ‫‪ ،TCP/IP‬ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‪.‬‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﻌﻨﻮﺍﻥ ﺑﺰﺭﮔﺘﺮﻳﻦ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ‪ ،‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻦ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ ﻗﺎﻧﻮﻧﻤﻨﺪ ﻧﻤﻮﺩﻥ ﻧﺤﻮﻩ‬ ‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﺠﻤﻮﻋﻪ ﻣﻘﺎﻻﺗﻲ ﮐﻪ ﺍﺭﺍﺋﻪ ﺧﻮﺍﻫﺪ ﺷﺪ ﺑﻪ‬

‫ﺑﺮﺭﺳﻲ ﺍﻳﻦ ﭘﺮﻭﺗﮑﻞ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﻣﻮﺍﺭﺩﻱ ﻫﻤﭽﻮﻥ‪ :‬ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ‪ ،‬ﻣﻌﺮﻓﻲ ﻭ ﺗﺸﺮﻳﺢ ﻻﻳﻪ ﻫﺎﻱ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻭ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﮐﺖ ﺑﺮﺍﻱ‬ ‫ﺍﻳﺠﺎﺩ ﺗﻤﺎﻳﺰ ﺩﺭ ﺍﺭﺗﺒﺎﻃﺎﺕ‪ ،‬ﺗﺸﺮﻳﺢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﻘﺪﻣﻪ‬

‫ﺍﻣﺮﻭﺯﻩ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺰﺭﮒ ﻭ ﺍﻏﻠﺐ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ ﻣﻮﺟﻮﺩ ﺍﺯ‬

‫ﭘﺮﻭﺗﮑﻞ ‪ ،TCP/IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺣﻤﺎﻳﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ، TCP/IP .‬ﺍﻣﮑﺎﻧﺎﺕ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻏﻴﺮﻣﺸﺎﺑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﺩ‪.‬‬ ‫ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻣﻬﻢ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﻣﻮﺍﺭﺩﻱ ﻫﻤﭽﻮﻥ ‪ :‬ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ‬

‫ﻣﺤﻴﻂ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ‪ ،‬ﺿﺮﻳﺐ ﺍﻃﻤﻴﻨﺎﻥ ﺑﺎﻻ ‪،‬ﻗﺎﺑﻠﻴﺖ ﮔﺴﺘﺮﺵ ﻭ ﺗﻮﺳﻌﻪ ﺁﻥ‪ ،‬ﺍﺷﺎﺭﻩ ﮐﺮﺩ‪ .‬ﺍﺯ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﺑﻤﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﻣﺘﻨﻮﻉ ﺁﻥ ﻧﻈﻴﺮ ﻭﺏ ﻭ‬ ‫ﻳﺎ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺗﻨﻮﻉ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺘﻪ ‪ TCP/IP‬ﻭ‬ ‫ﺍﺭﺗﺒﺎﻁ ﻣﻨﻄﻘﻲ ﻭ ﺳﻴﺴﺘﻤﺎﺗﻴﮏ ﺁﻧﻬﺎ ﺑﺎ ﻳﮑﺪﻳﮕﺮ‪ ،‬ﺍﻣﮑﺎﻥ ﺗﺤﻘﻖ ﺍﺭﺗﺒﺎﻁ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‬

‫ﺭﺍ ﺑﺎ ﺍﻫﺪﺍﻑ ﻣﺘﻔﺎﻭﺕ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﺑﺮﻗﺮﺍﺭﻱ ﻳﮏ ﺍﺭﺗﺒﺎﻁ‪ ،‬ﺷﺎﻣﻞ ﻓﻌﺎﻟﻴﺖ ﻫﺎﻱ‬ ‫ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ‪ :‬ﺗﺒﺪﻳﻞ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺁﺩﺭﺱ ‪ IP‬ﻣﻌﺎﺩﻝ‪ ،‬ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻣﻮﻗﻌﻴﺖ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻣﻘﺼﺪ‪ ،‬ﺑﺴﺘﻪ ﺑﻨﺪﻱ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺁﺩﺭﺱ ﺩﻫﻲ ﻭ ﺭﻭﺗﻴﻨﮓ ﺩﺍﺩﻩ ﻫﺎ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻣﻮﻓﻘﻴﺖ ﺁﻣﻴﺰ‬ ‫ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﻣﺠﻤﻮﻋﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺘﻪ ‪TCP/IP‬‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪.‬‬

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‫ﻣﻌﺮﻓﻲ ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬

‫‪ ، TCP/IP‬ﭘﺮﻭﺗﮑﻠﻲ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ‬

‫ﺑﺮ ﻭﻳﻨﺪﻭﺯ ‪ ۲۰۰۰‬ﺍﺳﺖ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮒ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﻃﺮﻳﻖ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﮐﻪ ﺩﺭ ﭼﻬﺎﺭﻻﻳﻪ ﻣﺠﺰﺍ‬ ‫ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﺷﺪﻩ ﺍﻧﺪ‪ ،‬ﻣﻴﺴﺮ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺘﻪ ‪، TCP/IP‬‬ ‫ﺩﺍﺭﺍﻱ ﻭﻇﻴﻔﻪ ﺍﻱ ﺧﺎﺹ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ) ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ( ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ﻳﮏ‬ ‫ﺍﺭﺗﺒﺎﻁ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎ‪ ،‬ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ‬

‫ﻧﻤﺎﻳﻨﺪ‪ ،TCP/IP .‬ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﺗﻔﮑﻴﮏ ﻭ ﺗﻤﺎﻳﺰ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺑﺎ ﺳﺎﻳﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺑﻮﺩﻩ ﻭ ﭘﺲ ﺍﺯ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﻫﺎ ﺍﺯ ﻳﮏ ﺑﺮﻧﺎﻣﻪ‪ ،‬ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻣﺘﻨﺎﻇﺮ‬

‫ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺗﻮﺳﻂ ﭘﺮﻭﺗﮑﻞ‬

‫‪ TCP/IP‬ﺍﺯ ﻣﺤﻠﻲ ﺑﻪ ﻣﺤﻞ ﺩﻳﮕﺮ‪ ،‬ﺑﺎ ﻓﺮﺁﻳﻨﺪ ﺍﺭﺳﺎﻝ ﻳﮏ ﻧﺎﻣﻪ ﺍﺯ ﺷـــﻬﺮﻱ ﺑﻪ ﺷــــﻬﺮ‪،‬‬ ‫ﻗﺎﺑﻞ ﻣﻘﺎﻳﺴﻪ ﺍﺳﺖ‪.‬‬

‫ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ ، TCP/IP‬ﺑﺎ ﻓﻌﺎﻝ ﺷﺪﻥ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍ ﺁﻏﺎﺯ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ‪ ،‬ﺩﺍﺩﻩ ﻫـﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺟﻬﺖ ﺍﺭﺳﺎﻝ ﺭﺍ ﺑﮕــﻮﻧﻪ ﺍﻱ ﺁﻣــﺎﺩﻩ ﻭ‬ ‫ﻓﺮﻣـــﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﻗﺎﺑﻞ ﺧﻮﺍﻧﺪﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺎﺷﻨﺪ‪ ) .‬ﻣﺸﺎﺑﻪ ﻧﻮﺷﺘﻦ‬

‫ﻧﺎﻣﻪ ﺑﺎ ﺯﺑﺎﻧﻲ ﮐﻪ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﻣﻄﺎﻟﻌﻪ ﺁﻥ ﺑﺎﺷﺪ(‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺁﺩﺭﺱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪،‬‬ ‫ﺑﻪ ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ ) ﻣﺸﺎﺑﻪ ﺁﺩﺭﺱ ﮔﻴﺮﻧﺪﻩ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﻧﺎﻣﻪ ﻣﺸﺨﺺ‬ ‫ﻣﻲ ﮔﺮﺩﺩ(‪ .‬ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﺩﺍﺩﻩ ﺑﻬﻤﺮﺍﻩ ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻲ ) ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ‬ ‫ﺗﺎﺋﻴﺪ ﺩﺭﻳﺎﻓﺖ ﺩﺭ ﻣﻘﺼﺪ (‪ ،‬ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ﺑﺤﺮﮐﺖ ﺩﺭﺁﻣﺪﻩ ﺗﺎ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺳﺪ‪.‬‬ ‫ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﺍﺭﺗﺒﺎﻃﻲ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺷﺒﮑﻪ ﺑﻤﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﺪﺍﺷﺘﻪ‪ ،‬ﻭ ﺗﺤﻘﻖ‬ ‫ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺑﺎ ﺭﻭﻳﮑﺮﺩﻱ ﻣﺴﺘﻘﻞ ﻧﺴﺒﺖ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻻﻳﻪ ﻫﺎﻱ ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬

‫‪ ، TCP/IP‬ﻓﺮﺁﻳﻨﺪﻫﺎﻱ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‬

‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺩﺭ ﭘﺸﺘﻪ ‪ TCP/IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﮐﺎﺭﺁﺋﻲ ﺩﺭ‬

‫ﺗﺤﻘﻖ ﻓﺮﺁﻳﻨﺪ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ‪ ،‬ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺁﺩﺭﺱ ﺩﻫﻲ ﺩﺭ ﺍﻧﺘﻬﺎ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﺭﺳﻲ ﺁﻥ ﺑﺎ ﺳﺮﻋﺖ ﻣﻄﻠﻮﺏ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﺻﺮﻓﺎ" ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‬ ‫ﮐﻪ ﺑﻌﻨﻮﺍﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﻣﻌﺮﻓﻲ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺍﻣﮑﺎﻥ ﺑﺎﺯ ﻧﻤﻮﺩﻥ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﺍﻧﺠﺎﻡ‬

‫ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻻﺯﻡ ﺑﺮ ﺭﻭﻱ ﺁﻥ ﺭﺍ ﺩﺍﺭﺍ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ ، TCP/IP .‬ﺍﺯ ﻳﮏ ﻣﺪﻝ ﺍﺭﺗﺒﺎﻃﻲ ﭼﻬﺎﺭ‬ ‫ﻻﻳﻪ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻣﺤﻠﻲ ﺑﻪ ﻣﺤﻞ ﺩﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪Application :‬‬

‫‪ ,Transport ,Internet‬ﻭ ‪ ،Interface Network‬ﻻﻳﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺮﻭﺗﮑﻞ‬ ‫‪ TCP/IP‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻭﺍﺑﺴﺘﻪ ﺑﻪ ﭘﺸﺘﻪ ‪ ، TCP/IP‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫ﺭﺳﺎﻟﺖ ﺧﻮﺩ ‪ ،‬ﺩﺭ ﻳﮑﻲ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﻧﺪ‪.‬‬

‫ﻻﻳﻪ ‪Application‬‬

‫ﻻﻳﻪ ‪ ، Application‬ﺑﺎﻻﺗﺮﻳﻦ ﻻﻳﻪ ﺩﺭ ﭘﺸﺘﻪ ‪ TCP/IP‬ﺍﺳﺖ‪ .‬ﺗﻤﺎﻣﻲ ﺑﺮﻧﺎﻣﻪ ﻭ ﺍﺑﺰﺍﺭﻫﺎﻱ‬

‫ﮐﺎﺭﺑﺮﺩﻱ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺩﺳﺘﺘﻴﺎﺑﻲ ﺑﻪ ﺷﺒﮑﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﺑﻤﻨﻈﻮﺭ ﻓﺮﻣﺖ ﺩﻫﻲ ﻭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﻧﺪ ‪ HTTP .‬ﻭ ‪ FTP‬ﺩﻭ ﻧﻤﻮﻧﻪ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ .(HTTP)Hyper text Transfer Protocol‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪،‬‬

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‫ﭘﺮﻭﺗﮑﻞ ‪ . (FTP)File Transfer Protocol‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﻭ‬

‫ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻓﺎﻳﻞ ﻫﺎﻱ ﺻﻔﺤﺎﺕ ﻭﺏ ﻣﺮﺑﻮﻁ ﺑﻪ ﻭﺏ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺩﺭﻳﺎﻓﺖ ﻓﺎﻳﻞ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻻﻳﻪ ‪Transport‬‬

‫ﻻﻳﻪ " ﺣﻤﻞ " ‪ ،‬ﻗﺎﺑﻠﻴﺖ ﺍﻳﺠﺎﺩ ﻧﻈﻢ ﻭ ﺗﺮﺗﻴﺐ ﻭ ﺗﻀﻤﻴﻦ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ‬

‫ﺑﻪ ﻻﻳﻪ ‪ ) Application‬ﻻﻳﻪ ﺑﺎﻻﻱ ﺧﻮﺩ( ﻭ ﻳﺎ ﻻﻳﻪ ﺍﻳﻨﺘﺮﻧﺖ ) ﻻﻳﻪ ﭘﺎﻳﻴﻦ ﺧﻮﺩ( ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ‬ ‫ﺩﺍﺭﺩ‪ .‬ﻻﻳﻪ ﻓﻮﻕ ‪ ،‬ﻫﻤﭽﻨﻴﻦ ﻣﺸﺨﺼﻪ ﻣﻨﺤﺼﺮﺑﻔﺮﺩﻱ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﮐﻪ ﺩﺍﺩﻩ ﺭﺍ ﻋﺮﺿﻪ ﻧﻤﻮﺩﻩ‬ ‫ﺍﺳﺖ ‪ ،‬ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻳﻦ ﻻﻳﻪ ﺩﺍﺭﺍﻱ ﺩﻭ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺎﺳﻲ ﺍﺳﺖ ﮐﻪ ﻧﺤﻮﻩ ﺗﻮﺯﻳﻊ ﺩﺍﺩﻩ ﺭﺍ‬

‫ﮐﻨﺘﺮﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫‪ .(TCP)Transmission Control Protocol‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﻣﺴﺌﻮﻝ ﺗﻀﻤﻴﻦ‬ ‫ﺻﺤﺖ ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ ‪.‬‬

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‫‪ .(Datagram Protocol UDP)User‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﻋﺮﺿﻪ ﺳﺮﻳﻊ‬

‫ﺍﻃﻼﻋﺎﺕ ﺑﺪﻭﻥ ﭘﺬﻳﺮﻓﺘﻦ ﻣﺴﺌﻮﻟﻴﺘﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻀﻤﻴﻦ ﺻﺤﺖ ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺭﺍ‬ ‫ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪.‬‬

‫ﻻﻳﻪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻻﻳﻪ "ﺍﻳﻨﺘﺮﻧﺖ"‪ ،‬ﻣﺴﺌﻮﻝ ﺁﺩﺭﺱ ﺩﻫﻲ‪ ،‬ﺑﺴﺘﻪ ﺑﻨﺪﻱ ﻭ ﺭﻭﺗﻴﻨﮓ ﺩﺍﺩﻩ ﻫﺎ‪ ،‬ﺍﺳﺖ‪ .‬ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﺷﺎﻣﻞ‬ ‫ﭼﻬﺎﺭ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺎﺳﻲ ﺍﺳﺖ‪:‬‬ ‫•‬

‫‪ . (IP)Internet Protocol‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﻣﺴﺌﻮﻝ ﺁﺩﺭﺳﻲ ﺩﺍﺩﻩ ﻫﺎ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ‬

‫ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ .(Protocol ARP)Address Resoulation‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﻣﺴﺌﻮﻝ ﻣﺸﺨﺺ‬

‫ﻧﻤﻮﺩﻥ ﺁﺩﺭﺱ ‪ (Access Control MAC)Media‬ﺁﺩﺍﭘﺘﻮﺭ ﺷﺒﮑﻪ ﺑﺮ ﺭﻭﻱ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺳﺖ‪.‬‬

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‫‪ . (ICMP)Internet Control Message Protocol‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﻣﺴﺌﻮﻝ‬

‫ﺍﺭﺍﺋﻪ ﺗﻮﺍﺑﻊ ﻋﻴﺐ ﻳﺎﺑﻲ ﻭ ﮔﺰﺍﺭﺵ ﺧﻄﺎﺀ ﺩﺭ ﺻﻮﺭﺕ ﻋﺪﻡ ﺗﻮﺯﻳﻊ ﺻﺤﻴﺢ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ .(Protocol Managemant IGMP)Internet Group‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪،‬‬

‫ﻣﺴﺌﻮﻝ ﻣﺪﻳﺮﻳﺖ ‪ Multicasting‬ﺩﺭ ‪ TCP/IP‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪.‬‬ ‫ﻻﻳﻪ ‪Network Interface‬‬

‫ﻻﻳﻪ " ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ " ‪ ،‬ﻣﺴﺌﻮﻝ ﺍﺳﺘﻘﺮﺍﺭ ﺩﺍﺩﻩ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺷﺒﮑﻪ ﻭ ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﺍﺯ‬ ‫ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﺷﺎﻣﻞ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻓﻴﺰﻳﮑﻲ ﻧﻈﻴﺮ ﮐﺎﺑﻞ ﺷﺒﮑﻪ ﻭ‬ ‫ﺁﺩﺍﭘﺘﻮﺭﻫﺎﻱ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ) ﺁﺩﺍﭘﺘﻮﺭ( ﺩﺍﺭﺍﻱ ﻳﮏ ﻋﺪﺩ ﺩﻭﺍﺯﺩﻩ ﺭﻗﻤﻲ ﻣﺒﻨﺎﻱ‬

‫ﺷﺎﻧﺰﺩﻩ ) ﻧﻈﻴﺮ‪ ( B5-50-04-22-D4-66 :‬ﺑﻮﺩﻩ ﮐﻪ ﺁﺩﺭﺱ ‪ ،MAC‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﻻﻳﻪ " ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ " ‪ ،‬ﺷﺎﻣﻞ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﺸﺎﺑﻪ ﻻﻳﻪ ﻫﺎﻱ ﻗﺒﻞ‪،‬‬ ‫ﻧﻤﻲ ﺑﺎﺷﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ Ethernet‬ﻭ ‪،(ATM)Asynchronous Transfer Mode‬‬

‫ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ‬ ‫ﺩﺍﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺑﺮﻧﺎﻣﻪ ﻫﺎ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻱ ﻣﺘﻌﺪﺩﻱ ﺩﺭ ﻳﮏ ﺯﻣﺎﻥ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﭼﻨﺪﻳﻦ ﺑﺮﻧﺎﻣﻪ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ، TCP/IP ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ‬ ‫ﺭﻭﺷﻲ ﺑﻤﻨﻈﻮﺭ ﺗﻤﺎﻳﺰ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﺩﻳﮕﺮ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ‪ ،‬ﺍﺯ ﻳﮏ ﺳﻮﮐﺖ‬ ‫) ‪ (Socket‬ﺑﻤﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺧﺎﺹ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺁﺩﺭﺱ ‪IP‬‬

‫ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ‪ ،‬ﻣﺴﺘﻠﺰﻡ ﻣﺸﺨﺺ ﺷﺪﻥ ﺁﺩﺭﺱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ‬ ‫ﻣﻘﺼﺪ ﺍﺳﺖ ) ﺷﺮﻁ ﺍﻭﻟﻴﻪ ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﻭ ﻧﻘﻄﻪ‪ ،‬ﻣﺸﺨﺺ ﺑﻮﺩﻥ ﺁﺩﺭﺱ ﻧﻘﺎﻁ‬ ‫ﺩﺭﮔﻴﺮ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺍﺳﺖ (‪ .‬ﺁﺩﺭﺱ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺩﺭﮔﻴﺮ ﺩﺭ ﻓﺮﺁﻳﻨﺪ ﺍﺭﺗﺒﺎﻁ‪ ،‬ﺗﻮﺳﻂ‬

‫ﻳﮏ ﻋﺪﺩ ﻣﻨﺤﺼﺮﺑﻔﺮﺩ ﮐﻪ ‪ IP‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻣﺸﺨﺺ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﻪ ﻫﺮﻳﮏ‬ ‫ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ ، ١٠,١,١ .١٠ : IP .‬ﻧﻤﻮﻧﻪ ﺍﻱ ﺩﺭ‬

‫ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ‪.‬‬

‫ﭘﻮﺭﺕ ‪TCP/UDP‬‬

‫ﭘﻮﺭﺕ ﻣﺸﺨﺼﻪ ﺍﻱ ﺑﺮﺍﻱ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻭ ﺩﺭ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﺎﺹ ﺍﺳﺖ ‪.‬ﭘﻮﺭﺕ ﺑﺎ ﻳﮑﻲ‬

‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻻﻳﻪ "ﺣﻤﻞ" ) ‪ TCP‬ﻭ ﻳﺎ ‪ ( UDP‬ﻣﺮﺗﺒﻂ ﻭ ﭘﻮﺭﺕ ‪ TCP‬ﻭ ﻳﺎ ﭘﻮﺭﺕ‬

‫‪ ، UDP‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﭘﻮﺭﺕ ﻣﻲ ﺗﻮﺍﻧﺪ ﻋﺪﺩﻱ ﺑﻴﻦ ﺻﻔﺮ ﺗﺎ ‪ ۶۵۵۳۵‬ﺭﺍ ﺷﺎﻣﻞ ﺷﻮﺩ‪ .‬ﭘﻮﺭﺕ‬ ‫ﻫﺎ ﺑﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ TCP/IP‬ﺳﻤﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﺑﻌﻨﻮﺍﻥ ﭘﻮﺭﺕ ﻫﺎﻱ "ﺷﻨﺎﺧﺘﻪ ﺷﺪﻩ "‬ ‫ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﺑﻪ ﺍﻋﺪﺍﺩ ﮐﻤﺘﺮ ﺍﺯ ‪ ۱۰۲۴‬ﺧﺘﻢ ﻭ ﺭﺯﻭ ﻣﻲ ﺷﻮﻧﺪ ﺗﺎ ﻫﻴﭽﮕﻮﻧﻪ ﺗﻌﺎﺭﺽ ﻭ‬ ‫ﺑﺮﺧﻮﺭﺩﻱ ﺑﺎ ﺳﺎﻳﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺑﻮﺟﻮﺩ ﻧﻴﺎﻳﺪ‪ .‬ﻣﺜﻼ" ﺑﺮﻧﺎﻣﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ FTP‬ﺍﺯ ﭘﻮﺭﺕ‬

‫‪ TCP‬ﺑﻴﺴﺖ ﻭ ﻳﺎ ﺑﻴﺴﺖ ﻭﻳﮏ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺳﻮﮐﺖ )‪(Socket‬‬

‫ﺳﻮﮐﺖ‪ ،‬ﺗﺮﮐﻴﺒﻲ ﺍﺯ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻭ ﭘﻮﺭﺕ ‪ TCP‬ﻭﻳﺎ ﭘﻮﺭﺕ ‪ UDP‬ﺍﺳﺖ‪ .‬ﻳﮏ‬

‫ﺑﺮﻧﺎﻣﻪ‪ ،‬ﺳﻮﮐﺘﻲ ﺭﺍ ﺑﺎ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻧﻮﻉ ﺳﺮﻭﻳﺲ )‪TCP‬‬

‫ﺑﺮﺍﻱ ﺗﻀﻤﻴﻦ ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﻭ ﻳﺎ ‪ (UDP‬ﻭ ﭘﻮﺭﺗﻲ ﮐﻪ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺑﺮﻧﺎﻣﻪ ﺍﺳﺖ‪ ،‬ﻣﺸﺨﺺ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺁﺩﺭﺱ ‪ IP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﻮﮐﺖ‪ ،‬ﺍﻣﮑﺎﻥ ﺁﺩﺭﺱ ﺩﻫﻲ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻭ‬ ‫ﭘﻮﺭﺕ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﺭﺍ ﮐﻪ ﺩﺍﺩﻩ ﻫﺎ ﺑﺮﺍﻱ ﺁﻥ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪) TCP/IP‬ﻗﺴﻤﺖ ﺩﻭﻡ (‬ ‫ﺩﺭ ﻗﺴﻤﺖ ﺍﻭﻝ‪ ،‬ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺑﻬﻤﺮﺍﻩ ﻻﻳﻪ ﻫﺎﻱ ﺁﻥ ﻣﻌﺮﻓﻲ ﮔﺮﺩﻳﻴﺪ‪ .‬ﺩﺭ ﺍﻳﻦ‬ ‫ﻗﺴﻤﺖ ‪ ،‬ﺑﻪ ﺑﺮﺭﺳﻲ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪TCP/IP‬ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫‪، TCP/IP‬ﺷﺎﻣﻞ ﺷﺶ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺎﺳﻲ) ‪ ( ARP، TCP,UDP,IP,ICMP,IGMP‬ﻭ‬

‫ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﮐﺎﺭﺑﺮﺩﻱ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺍﺳﺘﺎﺩﻧﺪﺍﺭﺩﻫﺎ‬ ‫ﻱ ﻻﺯﻡ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺭﺍ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺗﻤﺎﻣﻲ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺮﻭﺗﮑﻞ ‪ ، TCP/IP‬ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺷﺶ ﮔﺎﻧﻪ‬

‫ﻓﻮﻕ ﻣﺮﺗﺒﻂ ﻭ ﺍﺯ ﺧﺪﻣﺎﺕ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺁﻧﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺗﺸﺮﻳﺢ‬ ‫ﻋﻤﻠﮑﺮﺩ ﻭ ﺟﺎﻳﮕﺎﻩ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺍﺷﺎﺭﻩ ﺷﺪﻩ‪ ،‬ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ : TCP‬ﻻﻳﻪ ‪Transport‬‬

‫‪ ،(Transmission Control Protocol (TCP‬ﻳﮑﻲ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‬

‫‪ TCP/IP‬ﺍﺳﺖ ﮐﻪ ﺍﻣﮑﺎﻥ ﺗﻮﺯﻳﻊ ﻭ ﻋﺮﺿﻪ ﺍﻃﻼﻋﺎﺕ )ﺳﺮﻭﻳﺲ ﻫﺎ( ﺑﻴﻦ ﺻﺮﻓﺎ" ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ‪،‬‬ ‫ﺑﺎ ﺿﺮﻳﺐ ﺍﻋﺘﻤﺎﺩ ﺑﺎﻻ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﭼﻨﻴﻦ ﺍﺭﺗﺒﺎﻃﻲ )ﺻﺮﻓﺎ" ﺑﻴﻦ ﺩﻭ ﻧﻘﻄﻪ(‪Unicast ،‬‬ ‫ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺑﺎ ﺭﻭﻳﮑﺮﺩ ﺍﺗﺼﺎﻝ ﮔﺮﺍ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ‪ ،‬ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺮﻗﺮﺍﺭ ﮔﺮﺩﺩ‪ .‬ﭘﺲ ﺍﺯ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﺻﺮﻓﺎ"‬ ‫ﺍﺗﺼﺎﻝ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ‪ ،‬ﺑﺴــﻴﺎﺭ ﻣﻄﻤـــﺌﻦ ﻣﻲ ﺑﺎﺷﻨﺪ‪،‬‬ ‫ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺑﻪ ﺗﻀﻤﻴﻦ ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻣﺒﺪﺍﺀ‪ TCP ،‬ﺩﺍﺩﻩ ﻫﺎﺋﻲ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺭﺳﺎﻝ ﮔﺮﺩﻧﺪ ﺭﺍ ﺩﺭ ﺑﺴﺘﻪ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ )‪ (Packet‬ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،TCP ،‬ﺑﺴﺘﻪ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺗﺸﺨﻴﺺ ﻭ ﺩﺍﺩﻩ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﺭﺍ ﻣﺠﺪﺩﺍ" ﺍﻳﺠﺎﺩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪TCP‬‬ ‫‪ ،TCP‬ﺑﻤﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﮐﺎﺭﺍﺋﻲ‪ ،‬ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺼﻮﺭﺕ ﮔﺮﻭﻫﻲ ﺍﺭﺳﺎﻝ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،TCP.‬ﻳﮏ ﻋﺪﺩ ﺳﺮﻳﺎﻝ )ﻣﻮﻗﻌﻴﺖ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻧﺴﺒﺖ ﺑﻪ ﺗﻤﺎﻡ ﺑﺴﺘﻪ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ( ﺭﺍ ﺑﻪ ﻫﺮﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻭ ﺍﺯ ‪ Acknowledgment‬ﺑﻤﻨﻈﻮﺭ‬ ‫ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺩﺭﻳﺎﻓﺖ ﮔﺮﻭﻫﻲ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ‬

‫ﺻﻮﺭﺗﻴﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﺩﺭ ﻣﺪﺕ ﺯﻣﺎﻥ ﻣﺸﺨﺼﻲ ﻧﺴﺒﺖ ﺑﻪ ﺍﻋﻼﻡ ﻭﺻﻮﻝ ﺑﺴﺘﻪ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺍﻗﺪﺍﻡ ﻧﻨﻤﺎﻳﺪ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ‪ ،‬ﻣﺠﺪﺩﺍ" ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻋﻼﻭﻩ‬ ‫ﺑﺮﺍﻓﺰﻭﺩﻥ ﻳﮏ ﺩﻧﺒﺎﻟﻪ ﻋﺪﺩﻱ ﻭ ‪ Acknowledgment‬ﺑﻪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪TCP ،‬‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﭘﻮﺭﺕ ﻣﺮﺗﺒﻂ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺭﺍ ﻧﻴﺰ ﺑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺍﺿﺎﻓﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‪ ،‬ﺍﺯ ﭘﻮﺭﺕ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﻤﻨﻈﻮﺭ ﻫﺪﺍﻳﺖ ﺻﺤﻴﺢ ﺑﺴﺘﻪ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﺑﺮﻧﺎﻣﻪ ﻣﻨﺎﺳﺐ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺯ‬

‫ﭘﻮﺭﺕ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﺑﻤﻨﻈﻮﺭ ﺑﺮﮔﺮﺩﺍﻧﺪﻥ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﺑﺮﻧﺎﻣﻪ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‪،‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ TCP‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺩﺍﺭﻧﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺒﻞ ﺍﺯ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﻳﮏ ﺍﺗﺼﺎﻝ ﺑﻴﻦ ﺧﻮﺩ ﺍﻳﺠﺎﺩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﺗﺼﺎﻝ ﻓﻮﻕ‪،‬‬ ‫ﺍﺯ ﻧﻮﻉ ﻣﺠﺎﺯﻱ ﺑﻮﺩﻩ ﻭ ‪ Session‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭﮔﻴﺮ ﺩﺭ ﺍﺭﺗﺒﺎﻁ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ‪ TCP‬ﻭ ﺑﮑﻤﮏ ﻓﺮﺁﻳﻨﺪﻱ ﺑﺎ ﻧﺎﻡ‪ ، Three-Way handshake :‬ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻭ‬ ‫ﻫﺮ ﻳﮏ ﭘﺎﻳﺒﻨﺪ ﺑﻪ ﺭﻋﺎﻳﺖ ﺍﺻﻮﻝ ﻣﺸﺨﺺ ﺷﺪﻩ ﺩﺭ ﺍﻟﮕﻮﺭﻳﺘﻢ ﻣﺮﺑﻮﻃﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

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‫ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‪ ،‬ﺩﺭ ﺳﻪ ﻣﺮﺣﻠﻪ ﺻﻮﺭﺕ ﻣﻲ ﭘﺬﻳﺮﺩ‪:‬‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‪ ،‬ﺍﺗﺼﺎﻝ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ‬ ‫‪ ، Session‬ﻣﻘﺪﺍﺭﺩﻫﻲ ﺍﻭﻟﻴﻪ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﻋﺪﺩ ﻣﺮﺑﻮﻁ ﺑﻪ ﻣﻮﻗﻌﻴﺖ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺑﻴﻦ ﺗﻤﺎﻡ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﺍﻧﺪﺍﺯﻩ ﻣﺮﺑﻮﻁ ﺑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ(‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﺑﻪ ﺍﻃﻼﻋﺎﺕ ‪ Session‬ﺍﺭﺳﺎﻝ ﺷﺪﻩ‪ ،‬ﭘﺎﺳﺦ ﻣﻨﺎﺳﺐ ﺭﺍ‬ ‫ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‪ ،‬ﺍﺯ ﺷﺮﺡ ﻭﺍﻗﻌﻪ ﺑﮑﻤﮏ ‪ Acknowledgment‬ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﺁﮔﺎﻫﻲ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ : UDP‬ﻻﻳﻪ ‪Transport‬‬

‫‪ ،( UDP) User Datagram Protocol‬ﭘﺮﻭﺗﮑﻠﻲ ﺩﺭ ﺳﻄﺢ ﻻﻳﻪ "ﺣﻤﻞ" ﺑﻮﺩﻩ ﮐﻪ‬ ‫ﺑﺮﻧﺎﻣﻪ ﻣﻘﺼﺪ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﻧﻮﻉ ﺑﺪﻭﻥ ﺍﺗﺼﺎﻝ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ‬ ‫ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺳﺮﻋﺖ ﻣﻨﺎﺳﺐ ﺭﺍ ﺍﺭﺍﺋﻪ ﻭﻟﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﻀﻤﻴﻦ ﺻﺤﺖ ﺍﺭﺳﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺳﻄﺢ ﻣﻄﻠﻮﺑﻲ ﺍﺯ ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺑﻮﺟﻮﺩ ﻧﻤﻲ ﺁﻭﺭﺩ‪ UDP .‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺩﺍﺩﻩ ﻫﺎﻱ‬ ‫ﺩﺭﻳﺎﻓﺘﻲ ﺗﻮﺳﻂ ﻣﻘﺼﺪ‪ ،‬ﺑﻪ ‪ Acknowledgment‬ﻧﻴﺎﺯﻱ ﻧﺪﺍﺷﺘﻪ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ‬ ‫ﻭ ﻳﺎ ﺧﺮﺍﺑﻲ ﺩﺭ ﺩﺍﺩﻩ ﻫﺎﻱ ﺍﺭﺳﺎﻝ ﺷﺪﻩ‪ ،‬ﺗﻼﺵ ﻣﻀﺎﻋﻔﻲ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻣﺠﺪﺩ ﺩﺍﺩﻩ ﻫﺎ‪ ،‬ﺍﻧﺠﺎﻡ‬ ‫ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ ﺩﺍﺩﻩ ﻫﺎﺋﻲ ﮐﻤﺘﺮ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ﻭﻟﻲ ﻫﻴﭽﻴﮏ ﺍﺯ ﺩﺍﺩﻩ‬

‫ﻫﺎﻱ ﺩﺭﻳﺎﻓﺘﻲ ﻭ ﺻﺤﺖ ﺗﺴﻠﺴﻞ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺗﻀﻤﻴﻦ ﻧﻤﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪،‬‬ ‫ﺑﻤﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﭼﻨﺪﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‪ Broadcast‬ﻭ ﻳﺎ ‪،Multicast‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺑﻌﻤﻞ ﻣﻲ ﺁﻳﺪ ‪ .‬ﭘﺮﻭﺗﮑﻞ ‪ ،UDP‬ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺣﺠﻢ ﺍﻧﺪﮐﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺩﺍﺭﺍﻱ ﺍﻫﻤﻴﺖ ﺑﺎﻻﺋﻲ ﻧﻤﻲ ﺑﺎﻧﺸﺪ‪ ،‬ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ UDP‬ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﻫﻤﭽﻮﻥ ‪)،media Multicasting Streaming‬ﻧﻈﻴﺮ‬

‫ﻳﮏ ﻭﻳﺪﺋﻮ ﮐﻨﻔﺮﺍﻧﺲ ﺯﻧﺪﻩ( ﻭ ﻳﺎ ﺍﻧﺘﺸﺎﺭ ﻟﻴﺴﺘﻲ ﺍﺯ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﮐﻪ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻃﺎﺕ‬ ‫ﻣﺤﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﻣﺘﺪﺍﻭﻝ ﺍﺳﺖ ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، UDP‬ﺑﺮﻧﺎﻣﻪ ﻣﺒﺪﺍﺀ ﻣﻲ‬ ‫ﺑﺎﻳﺴﺖ ﭘﻮﺭﺕ ‪ UDP‬ﺧﻮﺩ ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﺎﻳﺪ ﺩﻗﻴﻘﺎ" ﻣﺸﺎﺑﻪ ﻋﻤﻠﻴﺎﺗﻲ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻣﻘﺼﺪ ﺍﻧﺠﺎﻡ ﺩﻫﺪ‪ .‬ﻻﺯﻡ ﺑﻪ ﻳﺎﺩﺁﻭﺭﻱ ﺍﺳﺖ ﮐﻪ ﭘـﻮﺭﺕ ﻫﺎﻱ ‪ UDP‬ﺍﺯ ﭘــــﻮﺭﺕ ﻫﺎﻱ ‪TCP‬‬ ‫ﻣﺠﺰﺍ ﻭ ﻣﺘــــﻤﺎﻳﺰ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ )ﺣﺘﻲ ﺍﮔﺮ ﺩﺍﺭﺍﻱ ﺷﻤﺎﺭﻩ ﭘﻮﺭﺕ ﻳﮑﺴﺎﻥ ﺑﺎﺷﻨﺪ(‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ : IP‬ﻻﻳﻪ ‪Internet‬‬

‫‪ ،( IP) Internet Protocol‬ﺍﻣﮑﺎﻥ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻣﺤﻞ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺍﺭﺗﺒﺎﻃﻲ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ، IP .‬ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺑﺪﻭﻥ ﺍﺗﺼﺎﻝ ﻭ ﻏﻴﺮﻣﻄﻤﺌﻦ ﺑﻮﺩﻩ ﮐﻪ ﺍﻭﻟﻴﻦ‬

‫ﻣﺴﺌﻮﻟﻴﺖ ﺁﻥ ﺁﺩﺭﺱ ﺩﻫﻲ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﺭﻭﺗﻴﻨﮓ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬

‫ﺍﺳﺖ ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ‪ IP‬ﻫﻤﻮﺍﺭﻩ ﺳﻌﻲ ﺩﺭ ﺗﻮﺯﻳﻊ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﻳﮏ‬ ‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﮔﺮﻓﺘﺎﺭ ﻣﺴﺎﺋﻞ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ‪ :‬ﮔﻢ ﺷﺪﻥ‪ ،‬ﺧﺮﺍﺑﻲ ‪ ،‬ﻋﺪﻡ ﺗﻮﺯﻳﻊ‬

‫ﺑﺎ ﺍﻭﻟﻮﻳﺖ ﻣﻨﺎﺳﺐ‪ ،‬ﺗﮑﺮﺍﺭ ﺩﺭ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺗﺎﺧﻴﺮ‪ ،‬ﮔﺮﺩﻧﺪ‪.‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ‪ ،‬ﭘﺮﻭﺗﮑﻞ‬ ‫‪ IP‬ﺗﻼﺷﻲ ﺑﻤﻨﻈﻮﺭ ﺣﻞ ﻣﺸﮑﻼﺕ ﻓﻮﻕ ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺩ )ﺍﺭﺳﺎﻝ ﻣﺠﺪﺩ ﺍﻃﻼﻋﺎﺕ‬

‫ﺩﺭﺧﻮﺍﺳﺘﻲ(‪ .‬ﺁﮔﺎﻫﻲ ﺍﺯ ﻭﺻﻮﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻣﻘﺼﺪ ﻭ ﺑﺎﺯﻳﺎﻓﺖ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﮔﻢ ﺷﺪﻩ‪ ،‬ﻣﺴﺌﻮﻟﻴﺘﻲ ﺍﺳﺖ ﮐﻪ ﺑﺮ ﻋﻬﺪﻩ ﻳﮏ ﻻﻳﻪ ﺑﺎﻻﺗﺮ ﻧﻈﻴﺮ ‪ TCP‬ﻭ ﻳﺎ ﺑﺮﻧﺎﻣﻪ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ‬ ‫ﺍﻃﻼﻋﺎﺕ‪ ،‬ﻭﺍﮔﺬﺍﺭ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﻋﻤﻠﻴﺎﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺗﻮﺳﻂ ‪IP‬‬

‫ﻣﻲ ﺗﻮﺍﻥ ‪ IP‬ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﻣﮑﺎﻧﻲ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺖ ﮐﻪ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺗﺐ ﺳﺎﺯﻱ ﻭ ﺗﻮﺯﻳﻊ ﺑﺴﺘﻪ‬

‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺁﻥ ﻣﺤﻞ‪ ،‬ﺻﻮﺭﺕ ﻣﻲ ﭘﺬﻳﺮﺩ‪ .‬ﺑﺴﺘﻪ ﻫﺎ ﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﻳﮑﻲ ﺍﺯ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻻﻳﻪ ﺣﻤﻞ )‪ TCP‬ﻭ ﻳﺎ ‪ (UDP‬ﻭ ﻳﺎ ﺍﺯ ﻃﺮﻳﻖ ﻻﻳﻪ " ﺍﻳﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ "‪ ،‬ﺑﺮﺍﻱ‬ ‫‪ IP‬ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺍﻭﻟﻴﻦ ﻭﻇﻴﻔﻪ ‪ ،IP‬ﺭﻭﺗﻴﻨﮓ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﻪ‬ ‫ﻣﻘﺼﺪ ﻧﻬﺎﺋﻲ ﺍﺳﺖ‪ .‬ﻫﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺷﺎﻣﻞ ﺁﺩﺭﺱ ‪ IP‬ﻣﺒﺪﺍﺀ ) ﻓﺮﺳﺘﻨﺪﻩ ( ﻭ ﺁﺩﺭﺱ ‪IP‬‬

‫ﻣﻘﺼﺪ ) ﮔﻴﺮﻧﺪﻩ ( ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ‪ ، IP‬ﺁﺩﺭﺱ ﻣﻘﺼﺪﻱ ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﺎﻳﺪ ﮐﻪ ﺩﺭ‬ ‫ﻫﻤﺎﻥ ﺳﮕﻤﻨﺖ ﻣﻮﺟﻮﺩ ﺑﺎﺷﺪ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭﺻﻮﺭﺗﻴﮑﻪ ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﺩﺭﻫﻤﺎﻥ ﺳﮕﻤﻨﺖ ﻧﺒﺎﺷﺪ‪ ، IP،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮏ ﺭﻭﺗﺮ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺮﺍﻱ ﺁﻥ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪.‬ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻭﻇﺎﻳﻒ ‪ ، IP‬ﺍﻳﺠﺎﺩ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ‬

‫ﻋﺪﻡ ﻭﺟﻮﺩ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ) ﺑﻼﺗﮑﻠﻴﻒ ! ( ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻣﺤﺪﻭﺩﻳﺖ‬ ‫ﺯﻣﺎﻧﻲ ﺧﺎﺻﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺪﺕ ﺯﻣﺎﻥ ﺣﺮﮐﺖ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ‪ ،‬ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪ ،‬ﺗﻮﺳﻂ ﻧﺴﺒﺖ ﺩﺍﺩﻥ ﻳﮏ ﻣﻘﺪﺍﺭ ‪ (Time To Live)TTL‬ﺑﻪ ﻫﺮ‬

‫ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺻﻮﺭﺕ ﻣﻲ ﭘﺬﻳﺮﺩ‪ ،TTL .‬ﺣﺪﺍﮐﺜﺮ ﻣﺪﺕ ﺯﻣﺎﻧﻲ ﺭﺍ ﮐﻪ ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﻗﺎﺩﺭ ﺑﻪ ﺣﺮﮐﺖ ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ﺍﺳﺖ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ) ﻗﺒﻞ ﺍﺯ ﺍﻳﻨﮑﻪ ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﮐﻨﺎﺭ ﮔﺬﺍﺷﺘﻪ ﺷﻮﺩ(‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ : ICMP‬ﻻﻳﻪ ‪Internet‬‬

‫‪ ،(Protocol Internet Control Message (ICMP‬ﺍﻣﮑﺎﻧﺎﺕ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ‬

‫ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﻭ ﮔﺰﺍﺭﺵ ﺧﻄﺎﺀ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻏﻴﺮﻗﺎﺑﻞ ﺗﻮﺯﻳﻊ ﺭﺍ ﻓﺮﺍﻫﻢ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪179‬‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ، ICMP‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﺭﻭﺗﺮﻫﺎ ﮐﻪ ﺍﺯ ‪ IP‬ﺑﻤﻨـــﻈﻮﺭ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺘــــﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﮔﺰﺍﺭﺵ ﺧﻄﺎﺀ ﻭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺤﺪﻭﺩ ﺩﺭ ﺭﺍﺑﻄﻪ ﻭﺿﻌﻴﺖ‬

‫ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ‪ ، IP‬ﻗﺎﺩﺭ ﺑﻪ ﺗﻮﺯﻳﻊ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ‬ ‫ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻧﺒﺎﺷﺪ‪ ICMP ،‬ﻳﮏ ﭘﻴﺎﻡ ﻣﺒﺘﻨﻲ ﺑﺮ ﻏﻴﺮﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ﺑﻮﺩﻥ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻣﺒﺪﺍﺀ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﭘﺮﻭﺗﮑﻞ ‪ IP‬ﺑﻤﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺑﻴﻦ ﺭﻭﺗﺮﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻭﻟﻲ ‪ ICMP‬ﺑﻪ ﻧﻤﺎﻳﻨﺪﮔﻲ ﺍﺯ ‪ ،TCP/IP‬ﻣﺴﺌﻮﻝ ﺍﺭﺍﺋﻪ ﮔﺰﺍﺭﺵ ﺧﻄﺎﺀ ﻭ ﻳﺎ ﭘﻴﺎﻡ‬ ‫ﻫﺎﻱ ﮐﻨﺘﺮﻟﻲ ﺍﺳﺖ‪ .‬ﺗﻼﺵ ‪ ، ICMP‬ﺩﺭ ﺍﻳﻦ ﺟﻬﺖ ﻧﻴﺴﺖ ﮐﻪ ﭘﺮﻭﺗﮑﻞ ‪ IP‬ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﻳﮏ‬

‫ﭘﺮﻭﺗﮑﻞ ﻣﻄﻤﺌﻦ ﻣﻄﺮﺡ ﻧﻤﺎﻳﺪ‪ ،‬ﭼﻮﻥ ﭘﻴﺎﻡ ﻫﺎﻱ ‪ ICMP‬ﺩﺍﺭﺍﻱ ﻫﻴﭽﮕﻮﻧﻪ ﻣﺤﺘﻮﻳﺎﺗﻲ ﻣﺒﻨﻲ ﺑﺮ‬ ‫ﺍﻋﻼﻡ ﻭﺻﻮﻝ ﭘﻴﺎﻡ )‪ ( Acknowledgment‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻧﻤﻲ ﺑﺎﺷﻨﺪ‪ ،ICMP .‬ﺻﺮﻓﺎ"‬

‫ﺳﻌﻲ ﺩﺭ ﮔﺰﺍﺭﺵ ﺧﻄﺎﺀ ﻭ ﺍﺭﺍﺋﻪ ﻓﻴﺪﺑﮏ ﻫﺎﻱ ﻻﺯﻡ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺤﻘﻖ ﻳﮏ ﻭﺿﻌﻴﺖ ﺧﺎﺹ‬ ‫ﺭﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ : IGMP‬ﻻﻳﻪ ‪Internet‬‬

‫‪ ، (Protocol Internet Group Managment (IGMP‬ﭘﺮﻭﺗﮑﻠﻲ ﺍﺳﺖ ﮐﻪ ﻣﺪﻳﺮﻳﺖ‬ ‫ﻟﻴﺴﺖ ﺍﻋﻀﺎﺀ ﺑﺮﺍﻱ ‪ ، Multicasting IP‬ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ‪ TCP/IP‬ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ ﺩﺍﺭﺩ‪IP .‬‬

‫‪ ،Multicasting‬ﻓﺮﺁﻳﻨﺪﻱ ﺍﺳﺖ ﮐﻪ ﺑﺮ ﺍﺳﺎﺱ ﺁﻥ ﻳﮏ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﮔﺮﻭﻫﻲ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺍﺯ‬ ‫ﮔﻴﺮﻧﺪﮔﺎﻥ ﮐﻪ ﮔﺮﻭﻩ ‪ multicat‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ ؛ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ IGMP .‬ﻟﻴﺴﺖ ﺍﻋﻀﺎﺀ‬ ‫ﺭﺍ ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻣﺪﻳﺮﻳﺖ ‪Multicasting IP‬‬

‫ﺗﻤﺎﻣﻲ ﺍﻋﻀﺎﺀ ﻳﮏ ﮔﺮﻭﻩ ‪ ، multicast‬ﺑﻪ ﺗﺮﺍﻓﻴﮏ ‪ IP‬ﻫﺪﺍﻳﺖ ﺷﺪﻩ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ‬

‫‪ ، Multicast IP‬ﮔﻮﺵ ﺩﺍﺩﻩ ﻭ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺑﻪ ﺁﻥ ﺁﺩﺭﺱ ﺭﺍ ﺩﺭﻳﺎﻓﺖ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﭼﻨﺪﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻧﻴﺎﺯﻣﻨﺪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻧﻈﻴﺮ ‪Streaming‬‬ ‫‪ media‬ﺑﺎﺷﻨﺪ‪ ،‬ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺭﺯﻭﺷﺪﻩ ﺑﺮﺍﻱ ‪ multicasting‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮﻫﺎ‬ ‫ﮐﻪ ﺑﻤﻨﻈﻮﺭ ﭘﺮﺩﺍﺯﺵ ‪ multicast‬ﭘﻴﮑﺮﺑﻨﺪﻱ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ‬ ‫ﺗﻤﺎﻣﻲ ﻣﺸﺘﺮﮐﻴﻦ ﮔﺮﻭﻩ ‪ multicast‬ﺍﺭﺳﺎﻝ ) ‪ ( Forward‬ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺭﺳﻴﺪﻥ‬ ‫ﺍﻃﻼﻋﺎﺕ ‪ Multicast‬ﺑﻪ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﺴﻴﺮ ﺍﺭﺗﺒﺎﻃﻲ‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﺎﻳﺖ ﺍﺯ ‪ Multicasting‬ﺑﺎﺷﻨﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ‬ ‫ﻭﻳﻨﻮﺯ ‪ ،٢٠٠٠‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ‪ ، IP Multicast‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ : ARP‬ﻻﻳﻪ ‪Internet‬‬

‫‪ ،(Protocol ARP) Address Resolution‬ﭘﺮﻭﺗﮑﻠﻲ ﺍﺳﺖ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﻣﺴﺌﻠﻪ "‬ ‫ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ" ﺭﺍ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺧﺮﻭﺟﻲ )‪ ،(Outgoing‬ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪.‬‬ ‫ﻣﺎﺣﺼﻞ ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‪ Mapping ،‬ﺁﺩﺭﺱ ‪ IP‬ﺑﻪ ﺁﺩﺭﺱ‪Media Access ( MAC‬‬

‫‪ ،(Control‬ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ‪ .‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﺯ ﺁﺩﺭﺱ ‪ ، MAC‬ﺑﻤﻨﻈﻮﺭ ﺗﺸﺨﻴﺺ ﺗﻌﻠﻖ ﻳﮏ‬ ‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺪﻭﻥ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ ، MAC‬ﮐﺎﺭﺕ‬ ‫ﻫﺎﻱ ﺷﺒﮑﻪ‪ ،‬ﺩﺍﻧﺶ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻻﻳﻪ ﺑﺎﻻﺗﺮ ﺑﻤﻨﻈﻮﺭ‬ ‫ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺩﺍﺭﺍ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

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‫ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﺳﻴﺪﻥ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻻﻳﻪ ‪ IP‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﺁﺩﺭﺱ ﻫﺎﻱ‬ ‫‪ MAC‬ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫‪ ،ARP‬ﺍﺯ ﺟﺪﻭﻟﻲ ﺧﺎﺹ ﺑﻤﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻭ ‪ MAC‬ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺤﻠﻲ ﺍﺯ ﺣﺎﻓﻈﻪ ﮐﻪ ﺟﺪﻭﻝ ﻓﻮﻕ ﺩﺭ ﺁﻧﺠﺎ ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪ Cache ARP ،‬ﻧﺎﻣﻴﺪﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ ARP Cache .‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺎﻣﻞ ‪ mapping‬ﻻﺯﻡ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ‬ ‫ﺭﻭﺗﺮﻫﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﺻﺮﻓﺎ" ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﺸﺎﺑﻪ ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪.‬‬ ‫‪Physical Address Resolution‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ ، ARP‬ﺁﺩﺭﺱ ‪ IP‬ﻣﻘﺼﺪ ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺧﺮﻭﺟﻲ ﺭﺍ ﺑﺎ ‪ARP‬‬

‫‪ Cache‬ﻣﻘﺎﻳﺴﻪ ﺗﺎ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﺪﺳﺖ ﺁﻭﺭﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﻮﺭﺩﻱ‬

‫ﭘﻴﺪﺍ ﮔﺮﺩﺩ‪ ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺍﺯ ‪ Cache‬ﺑﺎﺯﻳﺎﺑﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻏﻴﺮ ﺍﻳﻨﺼﻮﺭﺕ؛ ‪ARP‬‬ ‫ﺩﺭﺧﻮﺍﺳﺘﻲ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﻣﺎﻟﮑﻴﺖ ‪ IP‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ Broadcast ،‬ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ‬

‫ﻭﻱ ﻣﻲ ﺧﻮﺍﻫﺪ ﮐﻪ ﺁﺩﺭﺱ ‪ MAC‬ﺧﻮﺩ ﺭﺍ ﺍﻋﻼﻡ ﻧﻤﺎﻳﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ) ﺑﺎ ‪ IP‬ﻣﺮﺑﻮﻃﻪ‬ ‫( ‪ ،‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺁﺩﺭﺱ ‪ MAC‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ﺩﺭﺧﻮﺍﺳﺖ ﺭﺍ ﺑﻪ ‪ Cache‬ﺧﻮﺩ ﺍﺿﺎﻓﻪ‬ ‫ﻧﻤﻮﺩﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﭘﺎﺳﺦ ﻻﺯﻡ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﺭﺳﺎﻝ ﺁﺩﺭﺱ ‪ MAC‬ﺧﻮﺩ‪ ،‬ﺑﻪ ﻣﺘﻘﺎﺿﻲ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‬

‫‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﭘﺎﺳﺦ ‪ ARP‬ﺗﻮﺳﻂ ﺩﺭﺧﻮﺍﺳﺖ ﮐﻨﻨﺪﻩ‪ ،‬ﺩﺭﻳﺎﻓﺖ ﮔﺮﺩﻳﺪ‪ ،‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﺍﺳﺘﻨﺎﺩ ﺑﻪ‬ ‫ﺍﻃﻼﻋـﺎﺕ ﺟﺪﻳﺪ ﺩﺭﻳﺎﻓــــﺘﻲ‪ Cache ،‬ﻣﺮﺑﻮﻃﻪ ﺑﻬﻨﮕﺎﻡ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﻘﺼﺪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺳﮕﻤﻨﺘﻲ ﺩﻳﮕﺮ ﺑﺎﺷﺪ‪ ، ARP ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺭﺍ ﺑﻪ‬ ‫ﺭﻭﺗﺮ ﻣﺴﺌﻮﻝ ﺩﺭ ﺳﮕﻤﻨﺖ ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺗﻌﻤﻴﻢ ﺧﻮﺍﻫﺪ ﺩﺍﺩ )ﺩﺭ ﻣﻘﺎﺑﻞ ﺁﺩﺭﺱ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﻣﻘﺼﺪ (‪ .‬ﺭﻭﺗﺮ‪ ،‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﺴﺌﻮﻝ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻘﺼﺪ ﻭ ﻳﺎ ‪ Forwarding‬ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﺩﻳﮕﺮ ﺍﺳﺖ‪.‬‬

‫ﺩﺭ ﻗﺴﻤﺖ ﺳﻮﻡ ﺑﻪ ﺑﺮﺭﺳﻲ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﺍﺑﺰﺍﺭﻫﺎﻱ ﮐﻤﮑﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪،TCP/IP‬‬ ‫ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫‪182‬‬

‫ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﺳﻮﻡ (‬ ‫ﺩﺭ ﻗﺴﻤﺖ ﺍﻭﻝ‪ ،‬ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺑﻬـــﻤﺮﺍﻩ ﻻﻳﻪ ﻫﺎﻱ ﺁﻥ ﻣــــــﻌﺮﻓﻲ ﮔﺮﺩﻳﺪ‪.‬‬

‫ﺩﺭ ﻗﺴﻤﺖ ﺩﻭﻡ‪ ،‬ﺑﻪ ﺑﺮﺭﺳﻲ ﺑﺮﺧﻲ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻬﻢ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺘﻪ ‪TCP/IP‬‬

‫ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻗﺴﻤﺖ‪ ،‬ﺑﻪ ﺑﺮﺭﺳﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﺍﺑﺰﺍﺭﻫﺎﻱ ﮐﻤﮑﻲ ﻣﻮﺟﻮﺩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ‬ ‫ﭘﺮﻭﺗﮑﻞ‪ ،TCP/IP‬ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫ﻧﺴﺨﻪ ‪ TCP/IP‬ﭘﻴﺎﺩ ﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺩﺭ ﻭﻳﻨﺪﻭﺯ‪ ،‬ﺑﻬﻤﺮﺍﻩ ﺧﻮﺩ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ‬ ‫ﮐﺎﺭﺑﺮﺩﻱ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺟﺮﺍﻱ ﻭﻳﻨﺪﻭﺯ ‪٢٠٠٠‬‬

‫ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻤﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﮔﺴﺘﺮﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ‪ ،‬ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﺳﻪ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺍﺯ ﺍﺑﺰﺍﺭﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪ TCP/IP‬ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ :‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻋﻴﺐ ﻳﺎﺑﻲ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ ﻭ ﻧﺮﻡ ﺍﻓــﺰﺍﺭﻫﺎﻱ‬

‫ﺳﻤﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪.‬‬ ‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺗﺸﺮﻳﺢ ﺍﻣﮑﺎﻧﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺮ ﮔﺮﻭﻩ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻋﻴﺐ ﻳﺎﺑﻲ‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻋﻴﺐ ﻳﺎﺑﻲ‪ ،‬ﺍﻣﮑﺎﻥ ﺗﺸﺨﻴﺺ ﻭ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻥ ﻣﺴﺎﺋﻞ ﻣﺮﺗﺒﻂ ﺑﺎ ﺷﺒﮑﻪ ﺭﺍ ﺑﺮﺍﻱ‬

‫ﮐﺎﺭﺑﺮﺍﻥ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺍﻳﻦ ﺍﺑﺰﺍﺭﻫﺎ ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬ ‫‪ . ARP‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ Cache ،‬ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫‪Addreee Resolution Protocol‬‬

‫)‪ (ARP‬ﺭﺍ‬

‫ﻧﻤﺎﻳﺶ ﻭ ﺍﻣﮑﺎﻥ ﺍﺻﻼﺡ ﺁﻥ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﮐﺎﻓﻲ‬ ‫ﺍﺳﺖ ‪ ARP -a‬ﺭﺍ ﺩﺭ ﺧﻂ ﺩﺳﺘﻮﺭ ﺗﺎﻳﭗ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺟﺪﻭﻝ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ARP‬‬

‫‪ ، Cache‬ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ‪Entry‬‬ ‫ﺍﻳﺴﺘﺎ ﺭﺍ ﺑﻪ ﺟﺪﻭﻝ ﻣﺮﺑﻮﻃﻪ ﺍﺿﺎﻓﻪ ) ‪aa-00-62--٠٠ ١٥٧,٥٥,٨٥,٢١٢ s- arp‬‬ ‫‪ ،( c6-09‬ﻭ ﻳﺎ ﺍﻗﺪﺍﻡ ﺑﻪ ﺣﺬﻑ ﻳﮏ ‪ host‬ﺍﺯ ﺟﺪﻭﻝ ﻧﻤﻮﺩ )‪.( arp -d‬‬

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‫‪ . Hostname‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﺭﺍ ﻧﻤﺎﻳﺶ ﻣﻲ ﺩﻫﺪ‪ .‬ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﮐﺎﻓﻲ ﺍﺳﺖ ‪ Hostname‬ﺭﺍ ﺩﺭ ﺧﻂ ﺩﺳﺘﻮﺭ‪ ،‬ﺗﺎﻳﭗ ﻭ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﻮﺩ‬

‫ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ‪.‬‬ ‫‪ . IPConfig‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ‪ ،‬ﭘﻴﮑﺮﺑﻨﺪﻱ ﺟﺎﺭﻱ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺭﺍ ﻧﻤﺎﻳﺶ ) ﺁﺩﺭﺱ‬ ‫‪ ، IP‬ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ‪ ،‬ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ‪ ( ...‬ﻭ ﺍﻣﮑﺎﻥ ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﺁﻥ ﺭﺍ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ‪ ipcongig/help ،‬ﺭﺍ ﺩﺭ‬ ‫ﺧﻂ ﺩﺳﺘﻮﺭ ﺗﺎﻳﭗ ﺗﺎ ﺑﺎ ﻋﻤﻠﮑﺮﺩ ﺍﻳﻦ ﺑﺮﻧﺎﻣﻪ ﻭ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺁﺷﻨﺎ ﮔﺮﺩﻳﺪ‪.‬‬

‫‪ . Nbtstat‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪،‬ﺟﺪﻭﻝ ﻣﺤﻠﻲ ﺍﺳﺎﻣﻲ‪ NetBIOS‬ﺭﺍ ﻧﻤﺎﻳﺶ ﻣﻲ ﺩﻫﺪ‪ .‬ﺟﺪﻭﻝ‬ ‫ﻓﻮﻕ‪ ،‬ﺷﺎﻣﻞ ﻟﻴﺴﺘﻲ ﺍﺯ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻬﻤﺮﺍﻩ ‪ IP‬ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ )‪( mapping‬‬ ‫‪ . Netstat‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺟﻠﺴﻪ ﮐﺎﺭﻱ )‪ (Session‬ﭘﺮﻭﺗﮑﻞ‬ ‫‪ TCP/IP‬ﺭﺍ ﻧﻤﺎﻳﺶ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫‪ . Ping‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﭘﻴﮑﺮﺑﻨﺪﻱ ﻭ ﺍﺭﺗﺒﺎﻁ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ IP‬ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺑﺮﺭﺳﻲ ﻭ‬ ‫ﺗﺴﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ Ping .‬ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ ICMP‬ﺭﺍ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﺍﺭﺳﺎﻝ ﻭ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﭘﺎﺳﺦ ‪ ICMP‬ﺑﻪ ﺁﻥ ﺟﻮﺍﺏ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ‪.‬ﺑﻤﻨﻈﻮﺭ ﺗﺴﺖ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺁﺩﺭﺱ ‪IP‬‬

‫ﻭ ﻳﺎ ﻧﺎﻡ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ‪،‬‬

‫ﻓﺮﻣﺎﻥ ] ‪ PING [IP_Address or Computer_Name‬ﺭﺍ ﺗﺎﻳﭗ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﺑﻤﻨﻈﻮﺭ ﺗﺴﺖ ﭘﻴﮑﺮﺑﻨﺪﻱ ‪ TCP/IP‬ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﻮﺩ‪ ،‬ﺍﺯ ‪Local‬‬ ‫‪ Loopback‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﺋﻴﺪ‪ ،loopback Local .‬ﺷﺎﻣﻞ ﺁﺩﺭﺱ ‪١٢٧,٠,٠,١‬‬ ‫ﺍﺳﺖ‪( Ping 127.0.0.1).‬‬

‫‪ . Tracert‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﺭﺩﻳﺎﺑﻲ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺗﺎ ﺭﺳﻴﺪﻥ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫‪184‬‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻣﺠﻤﻮﻋﻪ ﻭﺳﻴﻌﻲ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﻳﻨﺪﻭﺯ ﻭ‬ ‫ﻳﺎ ﻏﻴﺮﻭﻳﻨﺪﻭﺯ ﻧﻈﻴﺮ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻳﻮﻳﻨﻴﮑﺲ‪ ،‬ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﻨﺪ ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﺍﻳﻦ‬ ‫ﻧﻮﻉ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺳﺮﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﻭﻟﻲ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ‬ ‫ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﺁﻧﺎﻥ )ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﺎﺋﻴﺪ ﺍﻋﺘﺒﺎﺭ ﻭ‬ ‫ﻫﻮﻳﺖ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺼﻮﺭﺕ ﻣﺘﻦ ﺷﻔﺎﻑ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ(‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﻗﺖ ﻻﺯﻡ ﺻﻮﺭﺕ ﭘﺬﻳﺮﺩ‬

‫‪.‬ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬

‫‪ . FTP‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ ،TCP‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻓﺎﻳﻞ ﺑﻴﻦ ﻭﻳﻨﺪﻭﺯ‬ ‫‪ ٢٠٠٠‬ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺁﻧﺎﻥ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ FTP‬ﻧﺼﺐ ﺷﺪﻩ‬ ‫ﺍﺳﺖ ‪ ،‬ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫‪ . Telnet‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺑﻪ ﻣﻨﺎﺑﻊ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ‬ ‫ﮐﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ Telnet‬ﺑﺮ ﺭﻭﻱ ﺁﻧﺎﻥ ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫‪ . Tftp‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ ، UDP‬ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﻓﺎﻳﻞ ﻫﺎﻱ ﮐﻮﭼﮏ ﺑﻴﻦ ﻭﻳﻨﺪﻭﺯ‬ ‫‪ ٢٠٠٠‬ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺁﻧﺎﻥ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪Trivial File (TFTP‬‬ ‫‪ ( Transfer Protocol‬ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺳﻤﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

‫ﺍﻳﻦ ﻧﻮﻉ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎ ﺍﻣﮑﺎﻥ ﭼﺎﭖ ﻭ ﺍﻧﺘﺸﺎﺭ ﺳﺮﻭﻳﺲ ﻫﺎ ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪ TCP/IP‬ﺩﺭ ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺳﺮﻭﻳﺲ ﭼﺎﭖ ‪ . TCP/IP‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ‪ ،‬ﺳﺮﻭﻳﺲ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﭼﺎﭖ ‪ TCP/IP‬ﺭﺍ‬ ‫ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺮﻭﻳﺲ ﻓﻮﻕ ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﭼﺎﭖ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺑﺮ‬ ‫ﺭﻭﻱ ﺁﻧﺎﻥ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻠﻲ ﺑﺠﺰ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﻧﺼﺐ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺑﻪ ﭼﺎﭘﮕﺮ ﻫﺎﻱ‬

‫ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﻨﺘﺮﻧﺖ )‪ .(IIS‬ﺑﺮﻧﺎﻣﻪ ‪ ، IIS‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ﻭﺏ‪ ،‬ﺍﺧﺒﺎﺭ‪ ،‬ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﻭ ﺍﺭﺳﺎﻝ ﻓﺎﻳﻞ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪185‬‬

‫‪ TCP/IP‬ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﺪ‪ ،IIS .‬ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﻧﺴﺨﻪ ﻫﺎﻱ‬

‫‪ Server‬ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺑﺼﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﻧﺼﺐ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﭘﻴﺸﻨﻬﺎﺩ ﻣﻲ ﮔﺮﺩﺩ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺑﻪ ﻋﻤﻠﮑﺮﺩ ﺍﻳﻦ ﺑﺮﻧﺎﻣﻪ ﻧﻴﺎﺯﻱ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ‬ ‫ﻣﺜﺎﻝ‬

‫ﺣﺬﻑ )‪ (Uninstall‬ﺁﻥ ﺍﺯ ﺭﻭﻱ ﺳﻴﺴﺘﻢ ﻧﻤﻮﺩ‪.‬‬

‫ﻣﺜﺎﻝ ‪ - ١‬ﻫﺪﻑ ‪ :‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ‪ Ping‬ﺑﻤﻨﻈﻮﺭ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ ﻋﻤﻠﮑﺮﺩ ﭘﺮﻭﺗﮑﻞ‬ ‫‪TCP/IP‬‬ ‫ﻣﺮﺣﻠﻪ ﻳﮏ ‪ :‬ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﮐﺎﺭﺑﺮ ﻣﺠﺎﺯ ‪ ،‬ﺑﻪ ﺷﺒﮑﻪ ﻭﺍﺭﺩ ﺷﻮﻳﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻭ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Prompt Command‬ﺭﺍ ﺍﺯ ﻣﺴﻴﺮ ‪| Start | Programs‬‬ ‫‪ Accessories‬ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺳﻪ ‪ :‬ﺩﺳﺘﻮﺭ ‪ ١٢٧,٠,٠,١ Ping‬ﺭﺍ ﺩﺭ ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻃﻪ ﺗﺎﻳﭗ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﻧﺘﺎﻳﺞ ‪ :‬ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﻣﺮﺍﺣﻞ ﻓﻮﻕ ‪ ،‬ﻧﺘﺎﻳﺞ ﺯﻳﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﺷﻮﺩ‪:‬‬

‫ﻧﺘﻴﺠﻪ ﻳﮏ ‪ :‬ﻣﻲ ﺑﺎﻳﺴﺖ ﭼﻬﺎﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﻭ ﭼﻬﺎﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭﻳﺎﻓﺖ ﻭ‬ ‫ﻫﻴﭽﮕﻮﻧﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﮔﻢ ﻧﮕﺮﺩﺩ‪ .‬ﺩﺭ ﻏﻴﺮ ﺍﻳﻨﺼﻮﺭﺕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺼﺐ ‪TCP/IP‬‬

‫ﻣﺸﮑﻼﺗﻲ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬

‫ﻧﺘﻴﺠﻪ ﺩﻭ ‪ :‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﭼﻬﺎﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﮔﺮﺩﺩ‪ ،‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ‬ ‫ﺻﺤﺖ ﻋﻤﻠﮑﺮﺩ ﻭ ﻧﺼﺐ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺍﺳﺖ‪.‬‬ ‫ﻧﺘﺎﻳﺞ ﺣﺎﺻﻞ ﺍﺯ ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ‪Ping‬‬ ‫‪C:\>ping 127.0.0.1‬‬ ‫‪Pinging 127.0.0.1 with 32 bytes of‬‬ ‫‪data:‬‬ ‫‪Reply from 127.0.0.1: bytes=32‬‬ ‫‪time<10ms TTL=128‬‬ ‫‪Reply from 127.0.0.1: bytes=32‬‬ ‫‪time<10ms TTL=128‬‬ ‫‪Reply from 127.0.0.1: bytes=32‬‬ ‫‪186‬‬

‫‪time<10ms TTL=128‬‬ ‫‪Reply from 127.0.0.1: bytes=32‬‬ ‫‪time<10ms TTL=128‬‬ ‫‪Ping statistics for 127.0.0.1:‬‬ ‫‪Packets: Sent = 4, Received = 4,‬‬ ‫‪Lost = 0 (0% loss),‬‬ ‫‪Approximate round trip times in‬‬ ‫‪milli-seconds:‬‬ ‫= ‪Minimum = 0ms, Maximum‬‬ ‫‪0ms, Average = 0ms‬‬ ‫ﻣﺜﺎﻝ ‪ - ٢‬ﻫﺪﻑ ‪ :‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ Ping‬ﻭ ‪ Hostname‬ﺑﻤﻨﻈﻮﺭ ﺻﺤﺖ ﻋﻤﻠﮑﺮﺩ‬ ‫‪TCP/IP‬‬ ‫• ﻣﺮﺣﻠﻪ ﻳﮏ ‪ :‬ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﮐﺎﺭﺑﺮ ﻣﺠﺎﺯ ‪ ،‬ﺑﻪ ﺷﺒﮑﻪ ﻭﺍﺭﺩ ﺷﻮﻳﺪ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺩﻭ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Prompt Command‬ﺭﺍ ﺍﺯ ﻣﺴﻴﺮ ‪| Start | Programs‬‬

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‫ﻣﺮﺣﻠﻪ ﺳﻪ ‪ :‬ﺩﺭ ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﺩﺳﺘﻮﺭ ‪ hostname‬ﺭﺍ ﺗﺎﻳﭗ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺩﺭ ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﺩﺳﺘﻮﺭ ‪ Computer_Name Ping‬ﺭﺍ‬

‫‪ Accessories‬ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﺗﺎﻳﭗ ﻧﻤﺎﺋﻴﺪ ‪ .‬ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ،‬ﻣﻘﺪﺍﺭ ﺑﺮﮔﺮﺩﺍﻧﺪﻩ ﺷﺪﻩ ﺩﺭ ﺍﺛﺮ ﺍﺟﺮﺍﻱ ﻓﺮﻣﺎﻥ ‪hostname‬‬ ‫ﺍﺳﺖ‪.‬‬

‫ﻧﺘﺎﻳﺞ ‪ :‬ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﻣﺮﺍﺣﻞ ﻓﻮﻕ ‪ ،‬ﻧﺘﺎﻳﺞ ﺯﻳﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﺷﻮﺩ‪:‬‬ ‫•‬

‫ﻧﺘﻴﺠﻪ ﻳﮏ ‪ :‬ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ )ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺍﺭﺍﻱ ﻧﺎﻡ ﺍﺧﺘﺼﺎﺻﻲ ﻣﺮﺑﻮﻁ ﺑﻪ‬ ‫ﺧﻮﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ(‬

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‫ﻧﺘﻴﺠﻪ ﺩﻭ ‪ :‬ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ ) ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ‬ ‫ﺑﻪ ﺧﻮﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ(‬ ‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫‪C:\> hostname‬‬ ‫‪Srco‬‬ ‫‪187‬‬

‫ ﺑﻬﻤﺮﺍﻩ ﻧﺎﻡ‬Ping ‫ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺳﺘﻮﺭ‬: ‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ‬

C:> Ping Srco Pinging Srco.Test.com [ 10.10.1.1] with 32 bytes of data: Reply from 10.10.1.1: bytes=32 time<10ms TTL=128 Reply from 10.10.1.1: bytes=32 time<10ms TTL=128 Reply from 10.10.1.1: bytes=32 time<10ms TTL=128 Reply from 10.10.1.1: bytes=32 time<10ms TTL=128 Ping statistics for 10.10.1.1: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 0ms, Maximum = 0ms, Average = 0ms

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‫ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﭼﻬﺎﺭﻡ (‬ ‫ﺁﻧﭽﻪ ﺗﺎﮐﻨﻮﻥ ﮔﻔﺘﻪ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬

‫ﻗﺴﻤﺖ ﺍﻭﻝ ‪ :‬ﻣﻌﺮﻓﻲ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺑﻬﻤﺮﺍﻩ ﻻﻳﻪ ﻫﺎﻱ ﺁﻥ‬

‫ﻗﺴﻤﺖ ﺩﻭﻡ ‪ :‬ﺑﺮﺭﺳﻲ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪TCP/IP‬‬ ‫ﻗﺴﻤﺖ ﺳﻮﻡ ‪ :‬ﺑﺮﺭﺳﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﺍﺑﺰﺍﺭﻫﺎﻱ ﮐﻤﮑﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬

‫ﺩﺭ ﺍﻳﻦ ﻗﺴﻤﺖ ﺑﻪ ﺑﺮﺭﺳﻲ ‪ ، Name Resoulation‬ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪ .‬ﻣﺎﺣﺼﻞ ﻓﺮﺁﻳﻨﺪ‬

‫ﻓﻮﻕ‪ ،‬ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ IP‬ﻣﭗ )‪ (map‬ﺷﺪﻩ ﺑﻪ ﻳﮏ ﻧﺎﻡ ﺍﺳﺖ ) ﺩﺭ ﺻﻮﺭﺗﻴــﮑﻪ ﻋﻤﻠﻴﺎﺕ ﺑﺎ‬ ‫ﻣﻮﻓﻘﻴﺖ ﺍﻧﺠﺎﻡ ﮔﺮﺩﺩ(‪ .‬ﺗﻤﺎﻣﻲ ﺍﺳﺎﻣﻲ ‪ ، User-friendly‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺁﺩﺭﺱ ﻣﻌﺎﺩﻝ ‪IP‬‬

‫ﻣﺮﺑﻮﻃﻪ ﻣﭗ ﺗﺎ ﺯﻣﻴﻨﻪ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻘﺎﺿﻲ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ‪، TCP/IP‬‬ ‫ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺁﺩﺭﺱ ‪ IP‬ﺁﻧﺎﻥ‪ ،‬ﺷﻨﺎﺳﺎﺋﻲ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ‪ ،‬ﺗﻤﺎﻳﻞ ﺑﻴﺸﺘﺮﻱ ﺑﺮﺍﻱ ﺑﺨﺎﻃﺮﺳﭙﺮﺩﻥ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺳﺎﻣﻲ‪ ،‬ﻧﺴﺒﺖ ﺑﻪ‬ ‫ﺍﻋﺪﺍﺩ) ﺁﺩﺭﺱ ﻫﺎﻱ ‪ ( IP‬ﺭﺍ ﺩﺍﺭﻧﺪ‪ .‬ﺑﺮﺍﻱ ﺁﺩﺭﺱ ﺩﻫــــﻲ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﺍﻧﻮﺍﻉ ﻣﺘﻔﺎﻭﺗﻲ ﻧﺎﻡ‬ ‫) ‪ ،( user friendly names‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﺑﻤﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ‬

‫ﺍﺳﺎﻣﻲ ﻭ ﺁﺩﺭﺱ ‪ IP‬ﻣﻌﺎﺩﻝ ﺁﻧﺎﻥ‪ ،‬ﺍﺯ ﺭﻭﻳﮑﺮﺩﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ‬

‫ﻧﺎﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‪ ،‬ﺍﺯ ﻳﮏ ﻓﺎﻳﻞ ﺍﻳﺴﺘﺎ ﻭ ﻳﺎ ﭘﻮﻳﺎ ﺑﻤﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﻧﻤﻮﺩﻥ ﺍﺳﺎﻣﻲ ﻭ ﺁﺩﺭﺱ ﻫﺎﻱ ‪IP‬‬ ‫ﻣﭗ ﺷﺪﻩ ﺑﻪ ﺁﻧﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻧﻈﻴﺮ ‪ IE‬ﻭ ‪ ،FTP‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺁﺩﺭﺱ ‪ IP‬ﻭ ﻳﺎ ﻧﺎﻡ ﺑﺮﺍﻱ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻲ ﺑﺎﺷﻨﺪ ‪.‬ﺯﻣﺎﻧﻴﮑﻪ ﺍﺯ ﻧﺎﻡ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻗﺒﻞ ﺍﺯ ﺁﻏﺎﺯ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﻃﺮﻳﻖ ﭘﺮﻭﺗﮑﻞ ‪ ،TCP/IP‬ﺍﺯ ﻓﺮﺁﻳﻨﺪﻱ ﺑﺎ ﻧﺎﻡ‬

‫‪ Resolution Name‬ﺍﺳﺘﻔﺎﺩﻩ ﺗﺎ ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﻣﺸﺨﺺ ﮔﺮﺩﺩ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻴﮑﻪ ﺁﺩﺭﺱ ‪ ،IP‬ﻣﺸﺨﺺ ﺷﺪﻩ ﺑﺎﺷﺪ ) ﺩﺭ ﻣﻘﺎﺑﻞ ﻣﺸﺨﺺ ﺷﺪﻥ ﻧﺎﻡ (‪ ،‬ﺍﺭﺗﺒﺎﻁ ﺑﻼﻓﺎﺻﻠﻪ‬ ‫ﺑﺮﻗﺮﺍﺭﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺍﻧﻮﺍﻉ ﻧﺎﻡ‬

‫ﺩﻭ ﻧﻮﻉ ﻧﺎﻡ ‪ user friendly‬ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ :‬ﺍﺳﺎﻣﻲ ﻣﻴﺰﺑﺎﻥ )‪ (Host‬ﻭ ﺍﺳﺎﻣﻲ‬

‫‪ . NetBIOS‬ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ‪ ،‬ﻧﺎﻣﻲ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺗﺎ ﺁﻥ‬

‫ﺭﺍ ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﻣﻴﺰﺑﺎﻥ ‪ TCP/IP‬ﻣﺸﺨﺺ ﻧﻤﺎﻳﺪ‪ .‬ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ‪ ،‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﻱ ﺣﺪﺍﮐﺜﺮ ‪٢٥٥‬‬ ‫ﮐﺎﺭﺍﮐﺘﺮ ) ﺣﺮﻭﻑ ﺍﻟﻔﺒﺎﺋﻲ‪ ،‬ﮐﺎﺭﺍﮐﺘﺮﻫﺎﻱ ﻋﺪﺩﻱ‪ ،‬ﻧﻘﻄﻪ ﻭ ‪ ( hyphens‬ﺑﺎﺷﺪ‪ .‬ﺍﺳﺎﻣﻲ ﻣﻴﺰﺑﺎﻥ‬ ‫ﺩﺍﺭﺍﻱ ﺍﺷﮑﺎﻝ ﻣﺘﻔﺎﻭﺗﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻧﺎﻡ ﻣﺴﺘﻌﺎﺭ )‪ (Alias‬ﻭ ‪ ، names Domain‬ﺩﻭ ﻧﻤﻮﻧﻪ‬

‫ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻧﺎﻡ ﻣﺴﺘﻌﺎﺭ‪ ،‬ﻧﺎﻣﻲ ﺧﺎﺹ ﻭ ﻣﺮﺗﺒﻂ ﺷﺪﻩ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﺍﺳﺖ‪) .‬ﻧﻈﻴﺮ ‪ .( Tehran :‬ﻳﮏ ‪ ، Domain name‬ﺑﻤﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﺍﺯ ﻧﻘﻄﻪ ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺟﺪﺍﮐﻨﻨﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‬ ‫)ﻣﺜﻼ" ‪( Tehran.Citys.com‬‬

‫ﻧﺎﻡ ‪ ، NetBIOS‬ﻳﮏ ﻧﺎﻡ ﺷﺎﻧﺰﺩﻩ ﮐﺎﺭﺍﮐﺘﺮﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻤﻨﻈﻮﺭ ﻣﺸﺨﺺ‬

‫ﻧﻤﻮﺩﻥ ﻳﮏ ﻣﻨﺒﻊ ‪ NetBIOS‬ﺑﺮﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯﻳﮏ ﻧﺎﻡ‪NetBIOS‬‬

‫ﺑﻤﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻳﮏ ﻭ ﻳﺎ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻴﮕﺮﺩﺩ‪.‬‬ ‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﺻﺮﻓﺎ" ﺍﺯ ﭘﺎﻧﺰﺩﻩ ﺣﺮﻑ ﺍﻭﻝ ﺁﻥ ﺑﺮﺍﻱ ﻧﺎﻡ ﻭ ﺍﺯ ﮐﺎﺭﺍﮐﺘﺮ ﻧﻬﺎﺋﻲ ﺑﻤﻨﻈﻮﺭ ﻣﺸﺨﺺ‬

‫ﻧﻤﻮﺩﻥ ﻣﻨﺒﻊ ﻭ ﻳﺎ ﺳﺮﻭﻳﺴﻲ ﮐﻪ ﺑﻪ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺷﺎﺭﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻧﻤﻮﻧﻪ ﺍﻱ‬ ‫ﺍﺯ ﻳﮏ ﻣﻨﺒﻊ ‪ ، NetBIOS‬ﻋﻨﺼﺮ ‪File and Print Sharing for Microsoft‬‬ ‫‪ Networks‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﺍﺳﺖ ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﻌﺎﻟﻴﺖ ﺧﻮﺩ‬

‫ﺭﺍ ﺁﻏﺎﺯ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﻋﻨﺼﺮ ﻓﻮﻕ‪ ،‬ﻳﮏ ﻧﺎﻡ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ‪ NetBIOS‬ﺭﺍ ﺭﻳﺠﺴﺘﺮ)ﺛﺒﺖ(‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻧﺎﻡ ﺛﺒﺖ ﺷﺪﻩ ﺷﺎﻣﻞ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﮐﺎﺭﺍﮐﺘﺮﻱ ﺍﺳﺖ ﮐﻪ ﺑﻴﺎﻧﮕﺮ ﻋﻨﺼﺮ ﺛﺒﺖ ﮐﻨﻨﺪﻩ‬ ‫ﺍﺳﺖ ) ﺑﺮﺍﻱ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻦ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﺣﺪﺍﮐﺜﺮ ﭘﺎﻧﺰﺩﻩ ﺣﺮﻑ ﻭ ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ‬

‫ﻋﻨﺼﺮ ﺛﺒﺖ ﮐﻨﻨﺪﻩ ﻧﺎﻡ‪ ،‬ﺍﺯ ﻳﮏ ﺣﺮﻑ ﺩﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ(‪ .‬ﺩﺭﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﻧﺎﻡ‬ ‫‪ ، NetBIOS‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺣﺪﺍﮐﺜﺮ ﭘﺎﻧﺰﺩﻩ ﮐﺎﺭﺍﮐﺘﺮ ﺑﺎﺷﺪ‪ .‬ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﺧﻮﺩ ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﻳﻦ‬ ‫ﻧﻮﻉ ﺍﺳﺎﻣﻲ ﻧﺪﺍﺷﺘﻪ ﻭ ﻧﺴﺨﻪ ﻫﺎﻱ ﻗﺒﻠﻲ ﻭﻳﻨﺪﻭﺯ ﻧﻴﺎﺯﻣﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺳﺎﻣﻲ ‪NetBIOS‬‬ ‫ﺑﻤﻨﻈﻮﺭ ﺣﻤﺎﻳﺖ ﺍﺯ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﺷﺒﮑﻪ ﺍﻱ‪ ،‬ﺩﺍﺭﻧﺪ‪.‬‬ ‫‪190‬‬

‫‪Static IP mapping‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﻳﮏ ﻧﺎﻡ ﺭﺍ ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ‪ ،‬ﻣﺸﺨﺺ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ ،‬ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻫﻤﭽﻨﺎﻥ ﻧﻴﺎﺯﻣﻨﺪ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺑﺮﺍﻱ ﺗﺤﻘﻖ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻻﺯﻡ ﺍﺳﺖ ﮐﻪ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ ، IP‬ﻣﭗ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﺎﺣﺼﻞ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ) ‪ ،( mapping‬ﺩﺭ ﻳﮏ ﺟﺪﻭﻝ ﺍﻳﺴﺘﺎ ﻭ ﻳﺎ ﭘﻮﻳﺎ ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻴﮑﻪ ﺍﺯ ﻳﮏ ﺟﺪﻭﻝ ﺍﻳﺴﺘﺎ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ ،‬ﻧﺘﺎﻳﺞ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ ﻳﮑﻲ ﺍﺯ ﻓﺎﻳﻞ ﻫﺎﻱ‬ ‫‪ Hosts‬ﻭ ﻳﺎ ‪ Lmhosts‬ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﻧﺪ) ﻓﺎﻳﻞ ﻫﺎ ﻱ ﻓﻮﻕ‪ ،‬ﻣﺘﻨﻲ ﻣﻲ ﺑﺎﺷﻨﺪ(‪ .‬ﻣﻬﻤﺘﺮﻳﻦ‬

‫ﻣﺰﻳﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺟﺪﻭﻝ ﺍﻳﺴﺘﺎ ‪ ،‬ﺍﻣﮑﺎﻥ ﺳﻔﺎﺭﺷﻲ ﻧﻤﻮﺩﻥ ﺁﻥ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ ﻓﺎﻳﻞ‬

‫) ﻣﺘﻨﻲ ( ﻭ ﻣﺤﻞ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ) ﺫﺧﻴﺮﻩ ﺑﺮ ﺭﻭﻱ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ( ﺁﻥ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻫﺮ‬ ‫ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻌﻲ ﺑﺎ ﻓﺮﮐﺎﻧﺲ ﺑﺎﻻﻱ ﺩﺳﺘﻴﺎﺑﻲ‪ ،‬ﺑﻪ ﻫﺮ ﻣﻴﺰﺍﻥ‬

‫ﮐﻪ ﺿﺮﻭﺭﺕ ﺩﺍﺭﺩ‪ entry ،‬ﺩﺭ ﺟﺪﻭﻝ ﻓﻮﻕ ﺛﺒﺖ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﺟﺪﺍﻭﻝ ﺍﻳﺴﺘﺎ‪ ،‬ﻳﮑﻲ ﺍﺯ‬ ‫ﭼﺎﻟﺶ ﻫﺎﻱ ﺍﺻﻠﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﻮﺩﻩ ﻭ ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺗﻌﺪﺍﺩ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﭗ ﺷﺪﻩ‪ ،‬ﺯﻳﺎﺩ‬

‫ﻭ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﻣﺘﻨﺎﻭﺑﺎ" ﺗﻐﻴﻴﺮ ﻳﺎﺑﻨﺪ‪ ،‬ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﺟﺪﺍﻭﻝ ﺍﻳﺴﺘﺎ ﻣﺴﺎﺋﻞ ﺧﺎﺹ ﺧﻮﺩ ﺭﺍ‬ ‫ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﻓﺎﻳﻞ ‪ . Hosts‬ﻓﺎﻳﻞ ﻓﻮﻕ‪ ،‬ﻳﮏ ﻓﺎﻳﻞ ﻣﺘﻨﻲ ﻭ ﺷﺎﻣﻞ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﭗ ﺷﺪﻩ ﺑﻪ ﺍﺳﺎﻣﻲ‬

‫ﻣﻴﺰﺑﺎﻥ ﺍﺳﺖ ‪ .‬ﻓﺎﻳﻞ ﻓﻮﻕ‪ ،‬ﺩﺍﺭﺍﻱ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﻣﻲ ﺗﻮﺍﻥ ﭼﻨﺪﻳﻦ ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ‪ IP‬ﻣﺸﺎﺑﻬﻲ ﻧﺴﺒﺖ ﺩﺍﺩ ‪.‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺭ ﺁﺩﺭﺱ ‪ ١٢٧,٩١,٤٥,١٢١ : IP‬ﺍﺯ ﻃﺮﻳﻖ ﻧﺎﻡ‬ ‫ﺣﻮﺯﻩ ‪ Tehran.Citys.Com‬ﻭ ﻳﺎ ﻧﺎﻡ ﻣﺴﺘﻌﺎﺭ ‪ Tehran‬ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﻤﻨﻈﻮﺭ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺯ ﻧﺎﻡ ﻣﺴﺘﻌﺎﺭ‬

‫‪ Tehran‬ﺩﺭ ﻣﻘﺎﺑﻞ ﻧﺎﻡ ‪ ،Domain‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫ﻫﺮ ‪ Entry‬ﺩﺭ ﻓﺎﻳﻞ ﻓﻮﻕ‪ ،‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﭘﻼﺕ ﻓﺮﻡ‪ ،‬ﻧﺴﺒﺖ ﺑﻪ ﺣﺮﻭﻑ ﺑﺰﺭﮒ ﻭ‬ ‫ﮐﻮﭼﮏ ﺣﺴﺎﺱ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﻭ ﻳﺎ ‪NT‬‬ ‫ﺑﺮ ﺭﻭﻱ ﺁﻧﻬﺎ ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺣﺴﺎﺳﻴﺖ ﻓﻮﻕ‪ ،‬ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﻓﺎﻳﻞ ‪ . LmHosts‬ﻓﺎﻳﻞ ﻓﻮﻕ‪ ،‬ﻳﮏ ﻓﺎﻳﻞ ﻣﺘﻨﻲ ﻭﺷﺎﻣﻞ ﺁﺩﺭﺱ ‪ IP‬ﻣﭗ ﺷﺪﻩ ﺑﻪ ﻧﺎﻡ‬ ‫‪ NetBIOS‬ﺍﺳﺖ‪ .‬ﺑﺨﺸﻲ ﺍﺯ ﻓﺎﻳﻞ ‪ Lmhosts‬ﺩﺭ ﺍﺑﺘﺪﺍ ﻭﺍﺭﺩ ﺣﺎﻓﻈﻪ ﺷﺪﻩ ﻭ ﺑﻪ ﺁﻥ‬

‫ﺍﺻﻄﻼﺣﺎ" ‪ NetBIOS name Cache‬ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬ ‫‪mapping Dynamic IP‬‬ ‫ﻣﻬﻤﺘﺮﻳﻦ ﻣﺰﻳﺖ ﺟﺪﺍﻭﻝ ﭘﻮﻳﺎ )ﻣﺴﺌﻮﻝ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ‪ IP‬ﻣﭗ ﺷﺪﻩ(‪ ،‬ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ‬ ‫ﺍﺗﻮﻣﺎﺗﻴﮏ ﺁﻧﺎﻥ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﺟﺪﺍﻭﻝ ﭘﻮﻳﺎ ﺍﺯ ﺩﻭ ﺳﺮﻭﻳﺲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪:‬‬

‫‪ (Domain Name System(DNS‬ﻭ ‪Windows Internet Neame (WINS‬‬ ‫‪ .(Service‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻭ ‪ WINS‬ﻋﻤﻠﻴﺎﺕ ﻣﺸﺎﺑﻪ ﺍﻱ ﺭﺍ ﻧﻈﻴﺮ ﻓﺎﻳﻞ ﻫﺎﻱ‬ ‫‪ Hosts‬ﻭ ‪ Lmhosts‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ ) ﺑﺪﻭﻥ ﻧﻴﺎﺯ ﺑﻪ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺩﺳﺘﻲ (‪.‬‬ ‫‪(Domain Name System)DNS‬‬

‫‪ ، DNS‬ﺭﻭﺷﻲ ﺑﻤﻨﻈﻮﺭ ﻧﺎﻣﮕﺬﺍﺭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﻣﻨﺎﺑﻊ ﺷﺒﮑﻪ ﺍﺳﺖ ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪ ، TCP/IP‬ﺍﺯ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺎﻣﻲ ‪ ،DNS‬ﺑﻤﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﺍﺳﺎﻣﻲ ‪ User friendly‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ ،Domain names‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ‬

‫ﮐﺎﺭﺑﺮﻱ ﻧﺎﻡ ﻳﮏ ‪ Domain‬ﺭﺍ ﺩﺭ ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﻭﺍﺭﺩ ) ﻣﺸﺨﺺ ( ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

‫‪ ، DNS‬ﻧﺎﻡ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﻪ ‪ IP‬ﻣﺮﺑﻮﻃﻪ‪ map ،‬ﺧﻮﺍﻫﺪ ﮐﺮﺩ ‪.‬ﺳﺎﺧﺘﺎﺭ ﺳﻴﺴﺘﻢ ﻧﺎﻣﮕﺬﺍﺭﻱ‬ ‫‪ ، DNS‬ﺑﺼﻮﺭﺕ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺍﺳﺖ‪ ،‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻴﺴﺘﻢ ﻓﻮﻕ‪ ،‬ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮔﻲ ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﻧﺖ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺳﻴﺴﺘﻢ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ‬ ‫ﺑﻤﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺍﺳﺎﻣﻲ ‪ ، Domain‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺍﺳﺎﻣﻲ ‪ Domain‬ﻭ ﻣﻌﺎﺩﻝ ‪ IP‬ﻣﺮﺑﻮﻃﻪ‬

‫ﺭﺍ ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺩﺍﺭﺍﻱ ‪ mapping‬ﻻﺯﻡ ﺑﺮﺍﻱ ﺻﺮﻓﺎ" ﻧﺎﺣﻴﻪ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺍﺻﻄﻼﺣﺎ"‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، DNS‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﺻﺮﻓﺎ" ﭘﺮﺩﺍﺯﺵ‬

‫ﻫﺎﻱ ﻻﺯﻡ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺩﺭ ﻣﻴﺪﺍﻥ ﻋﻤﻠﻴﺎﺗﻲ ﺁﻧﺎﻥ ﻣﻲ ﺑﺎﺷﺪ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ‪ mapping‬ﺩﺭ ﻧﺎﺣﻴﻪ ﻣﺮﺑﻮﻃﻪ ﺗﻐﻴﻴﺮ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﻋﻤﻠﻴﺎﺕ ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬

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‫‪(Windows Internet Name Service(WINS‬‬

‫‪ ، WINS‬ﻳﮏ ﺑﺎﻧـﮏ ﺍﻃﻼﻋــــﺎﺗﻲ ﺗﻮﺯﻳﻌﻲ ﺭﺍ ﺑﺮﺍﻱ ﺛﺒـــﺖ ‪ mapping‬ﭘﻮﻳﺎﻱ ﺍﺳــﺎﻣﻲ‬ ‫‪ NetBIOS‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،WINS .‬ﺍﺳﺎﻣﻲ ‪ NetBIOS‬ﺭﺍ ﺑـﻪ‬

‫ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﭗ ﻭ ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺁﻭﺭﺩ ﮐﻪ ﺍﺳــﺎﻣﻲ ‪ NetBIOS‬ﺩﺭ ﻃﻮﻝ‬ ‫ﺭﻭﺗﺮﻫﺎ‪ ،‬ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪ Name Resoulation‬ﺩﺭ ﻭﻳﻨﺪﻭﺯ ‪٢٠٠٠‬‬ ‫‪ ، Resoulation Name‬ﻓﺮﺁﻳﻨﺪﻱ ﺍﺳﺖ ﮐﻪ ﺑﺮ ﺍﺳﺎﺱ ﺁﻥ ﻣﺸﮑﻞ ﻳﮏ ﻧﺎﻡ ﺑﺮﻃﺮﻑ ﻭ ﻳﺎ ﺑﻪ‬ ‫ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻣﭗ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﺭﺑﺮﻱ ﻳﮏ ﻧﺎﻡ ﺭﺍ ﺩﺭ ﻳﮏ ﺑﺮﻧﺎﻣﻪ‪ ،‬ﻭﺍﺭﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪،‬‬

‫ﺑﺮﻧﺎﻣﻪ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﻧﺎﻡ ﻓﻮﻕ ﻳﮏ ﻣﻴﺰﺑﺎﻥ ﻭ ﻳﺎ ﻳﮏ ﻧﺎﻡ ‪ NetBIOS‬ﺍﺳﺖ‪ .‬ﺑﺮﻧﺎﻣﻪ‬ ‫ﻫﺎﻱ ﻓﻌﻠﻲ ﺩﺭ ﻭﻳﻨﺪﻭﺯ ‪ ،٢٠٠٠‬ﺍﺯ ﻓﺮﺁﻳﻨﺪ ‪ ، host name resolution‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‬

‫ﻭﻟﻲ ﺑﺮﺧﻲ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻗﺪﻳﻤﻲ ﺗﺮ ﻧﻈﻴﺮ ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﮐﻪ ﻣﺨﺘﺺ ﻭﻳﻨﺪﻭﺯ ‪ NT‬ﻭ ﻳﺎ ﻭﻳﻨﺪﻭﺯ‬ ‫‪ ٩٨ , ٩٥‬ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﻧﺪ‪ ،‬ﻫﻤﭽﻨﺎﻥ ﺍﺯ ﺍﺳﺎﻣﻲ ‪ NetBIOS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ‬ ‫ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ‪ ،‬ﺑﺎ ﻣﻮﻓﻘﻴﺖ ﻫﻤﺮﺍﻩ ﻧﮕﺮﺩﺩ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻣﺘﻘﺎﺿﻲ ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻣﻘﺼﺪ‬

‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺍﺯ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪name ،‬‬ ‫‪ resolution‬ﻧﻴﺎﺯ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﻓﺮﺁﻳﻨﺪ ‪Host name Resolution‬‬

‫ﺁﺩﺭﺱ ‪ IP‬ﺍﺳﺎﻣﻲ ﻣﻴﺰﺑﺎﻥ )‪ ، (Host Names‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺎﻳﻞ ‪ Host‬ﻭ ﻳﺎ ﺑﮑﻤﮏ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، DNS‬ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ‪ ،‬ﺑﺼﻮﺭﺕ ﺯﻳﺮ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪.‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺩﺳﺘﻮﺭﻱ ﺭﺍ ﻧﻈﻴﺮ ‪ FTP‬ﺑﻬﻤﺮﺍﻩ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ‪ ، B‬ﻭﺍﺭﺩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﺁﻳﺎ ﻧﺎﻡ ﻣﺸﺨﺺ ﺷﺪﻩ ﺑﺎ ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﻣﺤﻠﻲ ﻣﻄﺎﺑﻘﺖ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻧﺎﻡ ﻣﺸﺨﺺ ﺷﺪﻩ ﺑﺎ ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﻣﺤﻠﻲ ﻣﻄﺎﺑﻘﺖ ﻧﻨﻤﺎﻳﺪ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪، A‬‬

‫ﻓﺎﻳﻞ ﻣﻴﺰﺑﺎﻧﺎﻥ ﺧﻮﺩ ﺭﺍ )‪ ( Hosts File‬ﺑﻤﻨﻈﻮﺭ ﺁﮔﺎﻫﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ‪، B‬‬

‫ﺟﺴﺘﺠﻮ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﭘﻴﺪﺍ ﮔﺮﺩﺩ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﻣﭗ ﺷﺪﻩ‬ ‫ﺑﻪ ﺁﻥ‪ ،‬ﺑﺮﮔﺮﺩﺍﻧﺪﻩ ﺧﻮﺍﻫﺪ ﺷﺪ ‪ .‬ﭘﺲ ﺍﺯ ﻣﺸﺨﺺ ﺷﺪﻥ ﺁﺩﺭﺱ ‪ ، IP‬ﺯﻣﻴﻨﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺍﮔﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ B‬ﺭﺍ ﭘﻴﺪﺍ ﻧﻨﻤﺎﻳﺪ‪ ،‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻳﮏ ‪ query‬ﺑﺮﺍﻱ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﭘﻴﺪﺍ ﮔﺮﺩﺩ‪ ،‬ﺁﺩﺭﺱ‬ ‫‪ IP‬ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺑﻪ ﺁﻥ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﭘﺲ ﺍﺯ ﻣﺸﺨﺺ ﺷﺪﻥ ﺁﺩﺭﺱ ‪IP‬‬

‫‪ ،‬ﺯﻣﻴﻨﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫•‬

‫ﺩﺭﺻﻮﺭﺗﻴﮑﻪ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ ﺩﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﭘﻴﺪﺍ ﻧﮕﺮﺩﺩ‪ ،‬ﻭﻳﻨﺪﻭﺯ‬

‫‪ Cache ، ٢٠٠٠‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﺳﺎﻣﻲ ‪ NetBIOS‬ﺭﺍ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ ‪.‬ﺍﻳﻦ ﺍﻣﺮ ﺑﺪﻳﻦ‬

‫ﻋﻠﺖ ﺍﺳﺖ ﮐﻪ ﻭﻳﻨﺪﻭﺯ ‪ ، ٢٠٠٠‬ﺑﺎ ‪ name NetBIOS‬ﺑﻤﻨﺰﻟﻪ ‪، host name‬‬ ‫ﺭﻓﺘﺎﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ‪ Cache‬ﻓﻮﻕ ‪ ،‬ﺷﺎﻣﻞ ﻧﺎﻡ ﻣﻴﺰﺑﺎﻥ ﻣﻮﺭﺩ ﻧﻈﺮ ﻧﺒﺎﺷﺪ‪ ،‬ﻳﮏ ‪ query‬ﺑﺮﺍﻱ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ WINS‬ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ WINS‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻞ ﻣﺸﮑﻞ ﻧﺎﻡ ﻧﺒﺎﺷﺪ‪ ،‬ﻳﮏ ﭘﻴﺎﻡ‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﻴﺰﺑﺎﻧﻲ ﺑﻪ ﭘﻴﺎﻡ ﻣﻨﺘﺸﺮ ﺷﺪﻩ ﭘﺎﺳﺦ ﻧﺪﻫﺪ‪ ،‬ﻓﺎﻳﻞ ‪ Lmhosts‬ﺑﻤﻨﻈﻮﺭ ﻧﺎﻡ‬

‫‪ Broadcast‬ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻣﻴﺰﺑﺎﻥ) ‪ ، (NetBIOS‬ﺑﺮﺭﺳﻲ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﻓﺮﺁﻳﻨﺪ ‪Name Resolution NetBIOS‬‬

‫ﺑﺼﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ‪ ،‬ﺍﺳﺎﻣﻲ ‪ NetBIOS‬ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ‪TCP/IP‬‬

‫ﮐﺎﺭ ﻧﺨﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﻭﻳﻨﺪﻭﺯ ‪ ،٢٠٠٠‬ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪TCP/IP‬‬ ‫ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ‪ ، NetBIOS‬ﺍﺯ ﻃﺮﻳﻖ ﭘﺮﻭﺗﮑﻞ ‪ ، NetBT‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪194‬‬

‫‪ ، NetBT‬ﺍﺯ ﮐﻠﻤﺎﺕ ‪ NetBIOS over TCP/IP‬ﺍﻗﺘﺒﺎﺱ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﺑﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ ، NetBIOS‬ﺗﻮﺳﻂ ‪ TCP/IP‬ﻭ ﺍﺯ‬

‫ﻃﺮﻳﻖ ﺗﺮﺟﻤﻪ ﻧﺎﻡ ‪ NetBIOS‬ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ ،IP‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭﺻﻮﺭﺗﻴﮑﻪ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ‪ WINS‬ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ‪ ،‬ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﻓﺮﺁﻳﻨﺪ ‪NetBIOS Name‬‬ ‫‪ ، Resolution‬ﺑﺼﻮﺭﺕ ﺯﻳﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ‪:‬‬ ‫•‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﺩﺳﺘﻮﺭﻱ ﻧﻈﻴﺮ ‪ Net use‬ﺭﺍ ﺑﻬﻤﺮﺍﻩ ﻧﺎﻡ ‪ NetBIOS‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪،B‬‬ ‫ﻭﺍﺭﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﺁﻳﺎ ﻧﺎﻡ ﻣﺸﺨﺺ ﺷﺪﻩ ﺩﺭ ‪ Cache‬ﺍﺳﺎﻣﻲ‬ ‫‪ ، NetBIOS‬ﻣﻮﺟﻮﺩ ﺍﺳﺖ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻧﺎﻡ ﻣﻮﺟﻮﺩ ﻧﺒﺎﺷﺪ ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﻳﮏ ‪ query‬ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ WINS‬ﻗﺎﺩﺭ ﺑﻪ ﻳﺎﻓﺘﻦ ﻧﺎﻡ ﻧﺒﺎﺷﺪ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺍﺯ‬

‫‪ WINS‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪.‬‬

‫‪ Broadcast‬ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ‪ ، Broadcast‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻞ ﻣﺸﮑﻞ ﻧﺎﻡ ﻧﮕﺮﺩﺩ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻓﺎﻳﻞ‬ ‫‪ Lmhosts‬ﺭﺍ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺭﻭﺵ ﻫﺎﻱ ‪ NetBIOS‬ﻓﻮﻕ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻞ ﻣﺸﮑﻞ ﻧﺎﻡ ﻧﮕﺮﺩﻧﺪ‪،‬‬

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‫ﺩﺭ ﻧﻬﺎﻳﺖ ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻳﮏ ‪ query‬ﺑﺮﺍﻱ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺍﺭﺳﺎﻝ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻓﺎﻳﻞ ‪ Hosts‬ﺭﺍ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺩﺭ ﻗﺴﻤﺖ ﭘﻨﺠﻢ ﺑﻪ ﺑﺮﺭﺳﻲ ﻧﺤﻮﻩ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

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‫ﻣﻔﺎﻫﻴﻢ ﺍﻭﻟﻴﻪ ﭘﺮﻭﺗﮑﻞ ‪ ) TCP/IP‬ﻗﺴﻤﺖ ﭘﻨﺠﻢ (‬ ‫ﺁﻧﭽﻪ ﺗﺎﮐﻨﻮﻥ ﮔﻔﺘﻪ ﺷﺪﻩ ﺍﺳﺖ ‪:‬‬

‫ﻗﺴﻤﺖ ﺍﻭﻝ ‪ :‬ﻣﻌﺮﻓﻲ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺑﻬﻤﺮﺍﻩ ﻻﻳﻪ ﻫﺎﻱ ﺁﻥ‬

‫ﻗﺴﻤﺖ ﺩﻭﻡ ‪ :‬ﺑﺮﺭﺳﻲ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪TCP/IP‬‬ ‫ﻗﺴﻤﺖ ﺳﻮﻡ ‪ :‬ﺑﺮﺭﺳﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻭ ﺍﺑﺰﺍﺭﻫﺎﻱ ﮐﻤﮑﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬ ‫ﻗﺴﻤﺖ ﭼﻬﺎﺭﻡ‪ :‬ﺑﺮﺭﺳﻲ ‪Name Resoulation‬‬

‫ﺩﺭ ﺍﻳﻦ ﻗﺴﻤﺖ ﺑﻪ ﺑﺮﺭﺳﻲ ﻧﺤﻮﻩ ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫‪ ، TCP/IP‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺁﻧﻬﺎ ﺭﺍ ﺑﻪ ﺑﺨﺶ ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮﻱ ﺑﺎ ﻧﺎﻡ‬

‫‪ ) Packets‬ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ (‪ ،‬ﺗﻘﺴﻴﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﺁﻧﺎﻥ ﺑﺎ ﻭﺍﮊﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﻳﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺗﻘﺴﻴﻢ ﺩﺍﺩﻩ ﺑﻪ ﺑﺴﺘﻪ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺍﻣﺮﻱ ﺣﻴﺎﺗﻲ ﻭ ﺿﺮﻭﺭﻱ ﺍﺳﺖ‪ .‬ﺍﺭﺳﺎﻝ ﺣﺠﻢ ﺑﺎﻻﺋﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﻣﺪﺕ‬

‫ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ ﻃﻮﻝ ﺧﻮﺍﻫﺪ ﮐﺸﻴﺪ ﻭ ﻫﻤﻴﻦ ﺍﻣﺮ‪ ،‬ﺑﺎﻋﺚ ﮐﻨﺪ ﺷﺪﻥ ﺷﺒﮑﻪ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻧﻴﮑﻪ‬ ‫ﺣﺠﻢ ﺑﺎﻻﺋﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﺟﺎﺑﺠﺎ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ‪ ،‬ﺍﮔﺮ ﺩﺭ ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺍﺷﮑﺎﻟﻲ ﺑﺮﻭﺯ ﻧﻤﺎﻳﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﻣﺠﺪﺩﺍ" ﺍﺭﺳﺎﻝ ﺷﻮﻧﺪ‪ .‬ﺩﺭ ﻣﻘﺎﺑﻞ‪ ،‬ﺍﮔﺮ ﺑﺴﺘﻪ‬

‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻮﭼﮏ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﮔﺮﺩﻧﺪ‪ ،‬ﺍﻧﺘﻘﺎﻝ ﺁﻧﻬﺎ ﺑﺴﺮﻋﺖ ﺍﻧﺠﺎﻡ ﻭ ﻣﺤﻴﻂ‬ ‫ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﻣﺪﺕ ﺯﻳﺎﺩﻱ ‪ ،‬ﺍﺷﻐﺎﻝ ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ‬ ‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﺷﻮﻧﺪ‪ ،‬ﺻﺮﻓﺎ" ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻪ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ‬ ‫ﺷﺪﻩ ﺍﺳﺖ ‪ ،‬ﻣﺠﺪﺩﺍ" ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ ) .‬ﺩﺭ ﻣﻘﺎﺑﻞ ﺍﺭﺳﺎﻝ ﺗﻤﺎﻡ ﺍﻃﻼﻋﺎﺕ (‪.‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻻﻳﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‬ ‫)‪ ،( Network interface layer‬ﺑﻪ ﺁﻥ ﻓﺮﻳﻢ ) ‪ ( frame‬ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﻓﺮﻳﻢ ‪ ،‬ﺍﺯ ﺑﺨﺶ‬ ‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﻱ ﻋﻤﻠﮑﺮﺩ ﺧﺎﺹ ﺧﻮﺩ ﺩﺭ ﺟﺮﻳﺎﻥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻻﻳﻪ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

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‫ﻓﺮﺁﻳﻨﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺷﺎﻣﻞ ﻣﺮﺍﺣﻞ ﻣﺘــﻌﺪﺩﻱ ﺍﺳﺖ )ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﺩﺍﺩﻩ ﺩﺭﻭﻥ ﺑﺴﺘﻪ‬

‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﻭ ﺑﻬﻢ ﺑﺴﺘﻦ ﺁﻧﺎﻥ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﮕﻮﻧﻪ ﺍﻱ ﮐﻪ ﺷﮑﻞ‬

‫ﺍﻭﻟﻴﻪ ﻣﺠﺪﺩﺍ" ﺍﻳﺠﺎﺩ ﮔﺮﺩﺩ(‪ .‬ﻫﺮ ﻻﻳﻪ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ ، TCP/IP‬ﺩﺍﺭﺍﻱ ﻧﻘﺸﻲ ﻣﻮﺛﺮ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺍﺳﺖ‪.‬‬

‫ﻭﺍﮊﮔﺎﻥ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ) ‪( Packets‬‬ ‫ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ ﻻﻳﻪ ﻫﺎﻱ ‪ TCP/IP‬ﺍﺯ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ) ‪ ( packet‬ﺑﺎ ﺍﺳﺎﻣﻲ ﻣﺘﻔﺎﻭﺗﻲ ﻧﺎﻡ‬

‫ﺑﺮﺩﻩ ﻣﻲ ﺷﻮﺩ ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺣﺮﮐﺖ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻳﮏ ﻻﻳﻪ ﺑﻪ ﻻﻳﻪ ﺩﻳﮕﺮ ﺩﺭ ﭘﺮﻭﺗﮑﻞ‬ ‫‪ ، TCP/IP‬ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﺭﺍ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﺯ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻬﻤﺮﺍﻩ ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺑﻪ ﺁﻥ‪ ،‬ﺑﺎ ﺍﺳﺎﻣﻲ ﻓﻨﻲ ﺩﻳﮕﺮ‪ ،‬ﻳﺎﺩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﺍﺳﺎﻣﻲ ‪ ) Segment :‬ﺳﮕﻤﻨﺖ (‪ ) message ،‬ﭘﻴﺎﻡ (‪datagram ،‬‬ ‫) ﺩﻳﺘﺎﮔﺮﺍﻡ ( ﻭ ‪ ) frame‬ﻓﺮﻳﻢ (‪ ،‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫•‬

‫ﺳﮕﻤﻨﺖ ‪ .‬ﺳﮕﻤﻨﺖ ﻭﺍﺣﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ‪ TCP‬ﺑﻮﺩﻩ ﻭ ﺷﺎﻣﻞ ﻳﮏ ‪TCP‬‬

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‫ﭘﻴﺎﻡ ‪ .‬ﭘﻴﺎﻡ ‪ ،‬ﻭﺍﺣﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﻧﻈﻴﺮ‬

‫‪ header‬ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ‪ ، Application data‬ﻫﻤﺮﺍﻫﻲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫‪ .ICMP,UDP,IGMP‬ﻭ ‪ ARP‬ﺍﺳﺖ‪ .‬ﭘﻴﺎﻡ ﺷﺎﻣﻞ ﻳﮏ ‪header Protocol‬‬ ‫ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ‪ Application‬ﻭ ﻳﺎ ‪ ، protocol data‬ﻫﻤﺮﺍﻫﻲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺩﻳﺘﺎﮔﺮﺍﻡ ‪ .‬ﺩﻳﺘﺎﮔﺮﺍﻡ‪ ،‬ﻭﺍﺣﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺳﻄﺢ ﻻﻳﻪ ‪ IP‬ﺍﺳﺖ‪ .‬ﺩﻳﺘﺎﮔﺮﺍﻡ ﺷﺎﻣﻞ‬

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‫ﻓﺮﻳﻢ‪ .‬ﻓﺮﻳﻢ‪ ،‬ﻭﺍﺣﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺳﻄﺢ ﻻﻳﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﻓﺮﻳﻢ ﺷﺎﻣﻞ‬

‫ﻳﮏ ‪ IP header‬ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ﻻﻳﻪ ‪ ، transport‬ﻫﻤﺮﺍﻫﻲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﻳﮏ ‪ header‬ﺍﺳﺖ ﮐﻪ ﺩﺭ ﻻﻳﻪ ‪ network‬ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ﺩﺍﺩﻩ‬ ‫ﻻﻳﻪ ‪ ، IP‬ﻫﻤﺮﺍﻫﻲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﺍﺟﺰﺍﺀ ﻳﮏ ﻓﺮﻳﻢ‬

‫ﻳﮏ ﻓﺮﻳﻢ )ﺍﺻﻄﻼﺣﻲ ﺑﺮﺍﻱ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺳﻄﺢ ﻻﻳﻪ ﺷﺒﮑﻪ( ﺷﺎﻣﻞ ﺳﻪ‬ ‫ﺑﺨﺶ ﺍﺳﺎﺳﻲ‪ data , header :‬ﻭ ‪ trailer‬ﺍﺳﺖ‪.‬‬ ‫‪197‬‬

‫‪ . Header‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﺷﺎﻣﻞ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﺪ‪:‬‬ ‫•‬

‫ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﻫﺸﺪﺍﺭﺩﻫﻨﺪﻩ ﻣﺒﻨﻲ ﺑﺮ ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬

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‫ﺁﺩﺭﺱ ﻣﺒﺪﺍﺀ‬

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‫ﺁﺩﺭﺱ ﻣﻘﺼﺪ‬

‫‪ . Data‬ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻭﺍﻗﻌﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ ﺑﺮﻧﺎﻣﻪ ‪ ،‬ﻗﺮﺍﺭ ﻣﻲ ﮔﻴـــﺮﺩ‪ .‬ﺍﻳﻦ‬ ‫ﺑﺨﺶ ﺍﺯ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺍﺭﺍﻱ ﺍﻧﺪﺍﺯﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺖ ) ﺑﺴﺘﮕﻲ ﺑﻪ ﻣﺤﺪﻭﺩﻳﺖ ﺍﻧﺪﺍﺯﻩ‬ ‫ﺗﻨﻈﻴﻢ ﺷﺪﻩ ﺗﻮﺳﻂ ﺷﺒﮑﻪ ﺩﺍﺭﺩ(‪ .‬ﺑﺨﺶ ‪ ، Data‬ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ ﻧﻴﻢ ﮐﻴﻠﻮ ﺑﺎﻳﺖ ﺗﺎ ﭼﻬﺎﺭ‬ ‫ﮐﻴﻠﻮ ﺑﺎﻳﺖ ﺭﺍ ﻣﻲ ﺗﻮﺍﻧﺪ ﺷﺎﻣﻞ ﺷﻮﺩ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ‪ ،‬ﺍﻧﺪﺍﺯﻩ ﺩﺍﺩﻩ ﺗﻘﺮﻳﺒﺎ" ﻣﻌﺎﺩﻝ ﻳﮏ ﻭ‬

‫ﻧﻴﻢ ﮐﻴﻠﻮ ﺑﺎﻳﺖ ﺍﺳﺖ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺍﮐﺜﺮ ﺗﻨﻈﻴﻤﺎﺕ ﺩﺍﺩﻩ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ‪ ،‬ﺑﻴﺶ ﺍﺯ ﭼﻬﺎﺭ ﮐﻴﻠﻮ‬ ‫ﺑﺎﻳﺖ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺩﻩ ﺑﻪ ﺑﺨﺶ ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮﻱ ﺑﺎ ﻧﺎﻡ " ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋــﺎﺗﻲ "‬ ‫) ‪ ،( packet‬ﺗﻘﺴﻴﻢ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﻘﺎﻝ ﻳﮏ ﻓﺎﻳﻞ ﺑﺎ ﻇﺮﻓﻴﺖ ﺑﺎﻻ‪ ،‬ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺯﻳﺎﺩﻱ ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ﻣﻨﺘﻘﻞ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬ ‫‪ . Trailer‬ﻣﺤﺘﻮﻳﺎﺕ ‪ ، trailer‬ﺍﺭﺗﺒﺎﻁ ﻣﺴﺘﻘﻴﻢ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﻻﻳﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫ﺷﺒﮑﻪ ﺩﺍﺭﺩ‪ ، trailer .‬ﻣﻌﻤﻮﻻ" ﺷﺎﻣﻞ ﺑﺨﺸﻲ ﺑﻤﻨﻈﻮﺭ ﺑﺮﺭﺳﻲ ﺧﻄﺎﺀ ﺑﻮﺩﻩ ﮐﻪ‬ ‫‪ ،(Cyclical redundancy check(CRC‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ ،CRC.‬ﻋﺪﺩﻱ ﺍﺳﺖ ﮐﻪ‬

‫ﺗﻮﺳﻂ ﻳﮏ ﻣﺤﺎﺳﺒﻪ ﺭﻳﺎﺿﻲ ﺑﺮ ﺭﻭﻱ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺘﻲ ﺩﺭ ﻣﺒﺪﺍﺀ ) ﻓﺮﺳﺘﻨﺪﻩ(‪ ،‬ﺗﻮﻟﻴﺪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ ﺧﻮﺩ ﻣﻲ ﺭﺳﺪ‪ ،‬ﻣﺠﺪﺩﺍ" ﻣﺤﺎﺳﺒﻪ ﻣﺮﺑﻮﻃﻪ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻧﺘﺎﻳﺞ ﺑﺪﺳﺖ ﺁﻣﺪﻩ‪ ،‬ﻳﮑﺴﺎﻥ ﺑﺎﺷﺪ‪ ،‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺻﺤﺖ ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﺎﺣﺼﻞ ﻣﺤﺎﺳﺒﻪ ﺩﺭ ﻣﻘﺼﺪ ﺑﺎ ﻧﺘﻴﺠﻪ ﻣﺤﺎﺳﺒﻪ ﺷﺪﻩ ﺩﺭ ﻣﺒﺪﺍﺀ‪،‬‬

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‫ﻣﻐﺎﻳﺮﺕ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﺑﺪﻳﻦ ﻣﻔﻬﻮﻡ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ﮐﻪ ﺩﺍﺩﻩ ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﺗﻐﻴﻴﺮ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ‬ ‫ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺰ ﻣﺒﺪﺍﺀ‪ ،‬ﻣﺠﺪﺩﺍ" ﺩﺍﺩﻩ ﺭﺍ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫ﺟﺮﻳﺎﻥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ) ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﺗﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ (‬

‫ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺍﺯ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺍﺯ ﺑﻴﻦ ﻻﻳﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩ‬

‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻋﺒﻮﺭ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ‪ .‬ﺑﻤﻮﺍﺯﺍﺕ ﺭﺳﻴﺪﻥ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻳﮏ ﻻﻳﻪ‪،‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺁﻥ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺧﺎﺻﻲ ﺭﺍ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ‬ ‫ﺷﺪﻩ ) ﺿﻤﻴﻤﻪ ﺷﺪﻩ ( ﺗﻮﺳﻂ ﻫﺮ ﭘﺮﻭﺗﮑﻞ‪ ،‬ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺮﺭﺳﻲ ﺧﻄﺎﺀ ﺑﻮﺩﻩ‬ ‫ﮐﻪ ‪ ،Checksum‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺍﺯ ‪ ،Checksum‬ﺑﻤﻨﻈﻮﺭ ﺑﺮﺭﺳﻲ ﺻﺤﺖ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺩﺭ ‪ header‬ﺗﻮﺳﻂ ﭘﺮﻭﺗﮑﻞ ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺩﺭ ﭘﺮﻭﺗﮑﻞ ﻣﻘﺼﺪ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ )ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻲ ﮐﻢ ﻭ ﮐﺎﺳﺖ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﭘﺮﻭﺗﮑﻞ ﻣﻘﺼﺪ ﻗﺮﺍﺭ ﺑﮕﻴﺮﻧﺪ(‬ ‫‪.‬ﻓﺮﺍﻣﻮﺵ ﻧﮑﻨﻴﻢ ﮐﻪ ‪ ،CRC‬ﺻﺤﺖ ﺍﻧﺘﻘﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺭﺍ ﺑﻄﻮﺭ ﮐﺎﻣﻞ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﺩﺭ ﻫﺮ ﻻﻳﻪ‪ ،‬ﺑﻌﻨﻮﺍﻥ ﺩﺍﺩﻩ ﺗﻮﺳﻂ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻻﻳﻪ‬

‫ﺯﻳﺮﻳﻦ )ﭘﺎﻳﻴﻦ(‪ ،‬ﮐﭙﺴﻮﻟﻪ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻲ ﺭﺳﺪ‪،‬‬ ‫ﻻﻳﻪ ﻣﺮﺑﻮﻃﻪ ) ﻣﻨﺘﺎﻇﺮ ( ﻳﮏ ﺑﺨﺶ ﺍﺯ ‪ header‬ﺭﺍ ﺑﺮﺩﺍﺷﺘﻪ ﻭ ﺑﺎ ﺑﺎﻗﻲ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻌﻨﻮﺍﻥ‬

‫ﺩﺍﺩﻩ ﺑﺮﺧﻮﺭﺩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺴﻤﺖ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻻﻳﻪ‬

‫ﺑﺎﻻﺗﺮ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﺍﺧﺘﻴﺎﺭ ﭘﺮﻭﺗﮑﻞ ﻣﺮﺑﻮﻃﻪ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻋﻤﻠﮑﺮﺩ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﻻﻳﻪ ﻫﺎ ﺭﺍ ﺩﺭ ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺭﺳﻲ ﻭ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺭﺍ ﺍﺯ ﺯﺍﻭﻳﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﻭ‬ ‫ﻣﻘﺼﺪ ﺩﻧﺒﺎﻝ ﺧﻮﺍﻫﻴﻢ ﻧﻤﻮﺩ‪.‬‬

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‫ﻻﻳﻪ ‪Application‬‬

‫ﻓﺮﺁﻳﻨﺪ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻻﻳﻪ ‪ application‬ﺁﻏﺎﺯ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﻧﻈﻴﺮ ‪،FTP‬‬ ‫ﭘﺮﺩﺍﺯﺵ ﺭﺍ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﻣﻘﺪﺍﺭ ﺩﻫﻲ ﺍﻭﻟﻴﻪ ﻣﻲ ﻧﻤﺎﻳﺪ )ﺁﻣﺎﺩﻩ ﻧﻤﻮﺩﻥ ﺩﺍﺩﻩ ﺑﻪ ﻓﺮﻣﺘﻲ ﮐﻪ‬ ‫ﺑﺮﻧﺎﻣﻪ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺗﺸﺨﻴﺺ ﺁﻥ ﺑﺎﺷﺪ(‪ .‬ﺑﺮﻧﺎﻣﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‪،‬‬

‫ﮐﻨﺘﺮﻝ ﺗﻤﺎﻣﻲ ﻓﺮﺁﻳﻨﺪ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﻻﻳﻪ ‪Transport‬‬

‫ﺍﺯ ﻻﻳﻪ ‪ ، Application‬ﺩﺍﺩﻩ ﺑﻪ ﻻﻳﻪ ‪ transport‬ﻣﻨﺘﻘﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﻻﻳﻪ ﺷﺎﻣﻞ ﭘﺮﻭﺗﮑﻞ‬ ‫ﻫﺎﻱ ‪ TCP‬ﻭ ‪ UDP‬ﺍﺳﺖ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻧﻮﻉ ﭘﺮﻭﺗﮑﻞ "ﺣﻤﻞ" ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‬

‫)‪ TCP‬ﻳﺎ ‪ .( UDP‬ﺩﺭ ﻫﺮ ﺩﻭ ﺣﺎﻟﺖ ‪ Checksum‬ﺑﺮﺍﻱ ‪ TCP‬ﻭ ‪ UDP‬ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﭘﺮﻭﺗﮑﻞ ‪ ، TCP‬ﺍﻧﺘﺨﺎﺏ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻳﮏ ﺩﻧﺒﺎﻟﻪ ﻋﺪﺩﻱ ) ‪ ( number Sequence‬ﺑﻪ ﻫﺮ ﺳﮕﻤﻨﺖ ﻣﻨﺘﻘﻞ ﺷﺪﻩ ‪ ،‬ﺍﺿﺎﻓﻪ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫•‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Acknowledgment‬ﺑﺮﺍﻱ ﻳﮏ ﺍﺭﺗﺒﺎﻁ " ﺍﺗﺼﺎﻝ‪ -‬ﮔﺮﺍ" ‪ ،‬ﺑﻪ‬ ‫ﻫﺮ ﺳﮕﻤﻨﺖ ﺍﺿﺎﻓﻪ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫•‬

‫ﺷﻤﺎﺭﻩ ﭘﻮﺭﺕ ‪ TCP‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ‪ ،‬ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﭘﺮﻭﺗﮑﻞ ‪ ، UDP‬ﺍﻧﺘﺨﺎﺏ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺷﻤﺎﺭﻩ ﭘﻮﺭﺕ ‪ UDP‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ‪ ،‬ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻻﻳﻪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﭘﺲ ﺍﺯ ﺍﻳﻨﮑﻪ ﺍﻃﻼﻋﺎﺕ "ﺣﻤﻞ " ﺍﺿﺎﻓﻪ ﮔﺮﺩﻳﺪ ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ "ﺍﻳﻨﺘﺮﻧﺖ "‬ ‫ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻻﻳﻪ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺯﻳﺮ ﺑﻪ ‪ header‬ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺁﺩﺭﺱ ‪ IP‬ﻣﺒﺪﺍﺀ‬

‫•‬

‫ﺁﺩﺭﺱ ‪ IP‬ﻣﻘﺼﺪ‬

‫•‬

‫ﻧﻮﻉ ﭘﺮﻭﺗﮑﻞ "ﺣﻤﻞ "‬ ‫‪200‬‬

‫•‬ ‫•‬

‫ﻣﻘﺪﺍﺭ ‪checksum‬‬

‫ﺍﻃﻼﻋﺎﺕ ‪(Time to Live)TTL‬‬

‫ﻋﻼﻭﻩ ﺑﺮ ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ‪ ،‬ﻻﻳﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺴﺌﻮﻟﻴﺖ ﺑﺮ ﻃﺮﻑ ﻧﻤﻮﺩﻥ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﻘﺼﺪ ﺑﻪ‬ ‫ﻳﮏ ﺁﺩﺭﺱ ‪ MAC‬ﺭﺍ ﻧﻴﺰ ﺑﺮ ﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﭘﺮﻭﺗﮑﻞ ‪ ، ARP‬ﻣﺴﺌﻮﻝ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‪،‬‬ ‫ﺍﺳﺖ ‪ .‬ﺁﺩﺭﺱ ‪ MAC‬ﺑﻪ ‪ header‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺿﺎﻓﻪ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ " ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ "‪ ،‬ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﻻﻳﻪ "ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ "‬

‫ﻻﻳﻪ ﻓﻮﻕ‪ ،‬ﭘﺲ ﺍﺯ ﺩﺭﻳﺎﻓﺖ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻻﻳﻪ ‪ ، IP‬ﺍﻃﻼﻋﺎﺕ ﺯﻳﺮ ﺭﺍ ﺑﻪ ﺁﻥ ﺍﺿﺎﻓﻪ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪:‬‬ ‫•‬

‫ﻳﮏ ‪ ) Preamble‬ﻣﻘﺪﻣﻪ ( ‪ .‬ﺩﻧﺒﺎﻟﻪ ﺍﻱ ﺍﺯ ﺑﺎﻳﺖ ﻫﺎ ﺍﺳﺖ ﮐﻪ ﺍﺑﺘﺪﺍﻱ ﻳﮏ "ﻓﺮﻳﻢ " ﺭﺍ‬

‫ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ ‪.‬‬ ‫•‬

‫ﻳﮏ ‪ . CRC‬ﻣﺎﺣﺼﻞ ﻳﮏ ﻣﺤﺎﺳﺒﻪ ﺭﻳﺎﺿﻲ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﺍﻧﺘﻬﺎﻱ ﻓﺮﻳﻢ ﺍﺿﺎﻓﻪ ﻭ ﺍﺯ ﺁﻥ‬ ‫ﺑﻤﻨﻈﻮﺭ ﺻﺤﺖ ﺍﺭﺳﺎﻝ ﻓﺮﻳﻢ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﭘﺲ ﺍﺯﺍﻓﺰﻭﺩﻥ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻓﺮﻳﻢ ﻫﺎ ﺩﺭ ﻻﻳﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ‪ ،‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻓﺮﻳﻢ ﻫﺎ ﺑﺮ‬ ‫ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬

‫ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﻓﺮﻳﻢ ﻫﺎ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﻣﻲ ﺭﺳﻨﺪ‪ ،‬ﻻﻳﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﮑﻪ ‪ Preamble ،‬ﺭﺍ ﺣﺬﻑ‬ ‫ﻭ ﻣﻘﺪﺍﺭ ‪ CRC‬ﺭﺍ ﻣﺠﺪﺩﺍ" ﻣﺤﺎﺳﺒﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﻣﻘﺪﺍﺭ ﺑﺪﺳﺖ ﺁﻣﺪﻩ ﺑﺎ ﻣﻘﺪﺍﺭ‬

‫ﻣﺤﺎﺳﺒﻪ ﺷﺪﻩ ﺩﺭ ﻣﺒﺪﺍﺀ‪ ،‬ﻳﮑﺴﺎﻥ ﺑﺎﺷﺪ ﺩﺭ ﺍﺩﺍﻣﻪ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻘﺼﺪ‪ ،‬ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻓﺮﻳﻢ‪،‬‬

‫ﺑﺮﺭﺳﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺁﺩﺭﺱ ‪ ، MAC‬ﻳﮏ ﺁﺩﺭﺱ ‪ Broadcast‬ﻭ ﻳﺎ ﺁﺩﺭﺱ‬ ‫‪ MAC‬ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﻣﻄﺎﺑﻘﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﻓﺮﻳﻢ ﺑﻪ ﻻﻳﻪ "ﺍﻳﻨﺘﺮﻧﺖ "‪ ،‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ‬

‫ﻏﻴﺮ ﺍﻳﻨﺼﻮﺭﺕ ﻓﺮﻳﻢ ﻧﺎﺩﻳﺪﻩ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﻻﻳﻪ ‪ ،IP‬ﻣﺠﺪﺩﺍ" ‪ Checksum‬ﻣﺤﺎﺳﺒﻪ ﻭ‬

‫ﺑﺎ ﻣﻘﺪﺍﺭ ﻣﺤﺎﺳﺒﻪ ﺷﺪﻩ ﻗﺒﻞ ﺍﺯ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﻣﻘﺎﻳﺴﻪ ﺗﺎ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺣﺎﺻﻞ ﮔﺮﺩﺩ ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺩﺭ ﻃﻮﻝ ﻣﺴﻴﺮ ﺗﻐﻴﻴﺮ ﻧﻨﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‪ IP،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﭘﺮﻭﺗﮑﻞ"ﺣﻤﻞ" ‪،‬‬ ‫‪201‬‬

‫ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﺪ ) ‪ TCP‬ﻳﺎ ‪ .( UDP‬ﺑﻤﻨﻈﻮﺭ ﺗﺼﻤﻴﻢ ﮔﻴﺮﻱ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﻮﻉ ﭘﺮﻭﺗﮑﻞ "ﺣﻤﻞ "‬ ‫‪ ،‬ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ‪ header IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻻﻳﻪ "ﺣﻤﻞ"‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ‪ TCP‬ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺩﻧﺒﺎﻟﻪ ﻋﺪﺩﻱ ) ‪ ( sequence number‬ﺑﺮ‬ ‫ﺭﻭﻱ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺭﺳﻲ ﻭ ﻳﮏ ‪ acknowledgement‬ﺑﺮﺍﻱ ‪ TCP‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﭘﻮﺭﺕ ‪ TCP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺗﺎ‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﻻﻳﻪ ‪، Application‬ﺍﺭﺳﺎﻝ ﮔﺮﺩﺩ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ‪ UDP‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺍﺯ ﻻﻳﻪ "ﺍﻳﻨﺘﺮﻧﺖ" ﺩﺭﻳﺎﻓﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﭘﻮﺭﺕ‬

‫‪ UDP‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺗﺎ ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﻻﻳﻪ‬

‫‪ Application‬ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪ ) .‬ﺑﺪﻭﻥ ﺍﺭﺳﺎﻝ ﻳﮏ ‪ acknowledgement‬ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﻣﺒﺪﺍﺀ(‪.‬‬

‫ﭘﺲ ﺍﺯ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ‪ ، Appliaction‬ﭘﺮﺩﺍﺯﺵ ﻫﺎﻱ ﻻﺯﻡ ﻭ ﺿﺮﻭﺭﻱ ﺩﺭ ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﺎ ﺁﻧﻬﺎ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫‪DNS‬‬ ‫‪ DNS‬ﻣﺴﺌﻮﻟﻴﺖ ﺣﻞ ﻣﺸﮑﻞ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ) ﺗﺮﺟﻤﻪ ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ ( ﺩﺭ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ﻭ ﻣﺴﺎﺋﻞ ﻣﺮﺗﺒﻂ ﺑﺎ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ Winsock‬ﺭﺍ ﺑﺮ ﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ‬ ‫ﺑﺮﺧﻲ ﺍﺯ ﻣﻔﺎﻫﻴﻢ ﮐﻠﻴﺪﻱ ﻭ ﺍﺳﺎﺳﻲ ‪ ، DNS‬ﻻﺯﻡ ﺍﺳﺖ ﮐﻪ ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﺭﺍ ﺑﺎ ﺳﻴﺴﺘﻢ ﺩﻳﮕﺮ‬ ‫ﻧﺎﻣﮕﺬﺍﺭﻱ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ)‪ ( NetBIOS‬ﻣﻘﺎﻳﺴﻪ ﻧﻤﺎﺋﻴﻢ‪.‬‬

‫ﻗﺒﻞ ﺍﺯ ﻋﺮﺿﻪ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﺗﻤﺎﻣﻲ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺍﺯ ﻣﺪﻝ ‪ NetBIOS‬ﺑﺮﺍﻱ‬ ‫ﻧﺎﻣﮕﺬﺍﺭﻱ ﻣﺎﺷﻴﻦ ﻫﺎ ﻭ ﺳﺮﻭﻳﺲ ﻫﺎ ﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﺮﺩﻧﺪ‪.‬‬ ‫‪ NetBIOS‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٣‬ﺑﻪ ﺳﻔﺎﺭﺵ ﺷﺮﮐﺖ ‪ IBM‬ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺩﺭ‬

‫ﺍﺑﺘﺪﺍ ﺑﻌﻨﻮﺍﻥ ﭘﺮﻭﺗﮑﻠﻲ ﺩﺭ ﺳﻄﺢ ﻻﻳﻪ " ﺣﻤﻞ " ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﮐﺮﺩ‪.‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﺠﻤﻮﻋﻪ‬ ‫ﺩﺳﺘﻮﺭﺍﺕ ‪ NetBIOS‬ﺑﻌﻨﻮﺍﻥ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﺮﺑﻮﻁ ﺑﻪ ﻻﻳﻪ ‪ Session‬ﻧﻴﺰ ﻣﻄﺮﺡ ﺗﺎ ﺍﺯ‬ ‫ﺍﻳﻦ ﻃﺮﻳﻖ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﻧﻴﺰ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ NetBEUI .‬ﻣﻬﻤﺘﺮﻳﻦ ﻭ ﺭﺍﻳﺞ‬

‫ﺗﺮﻳﻦ ﻧﺴﺨﻪ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ‪ NetBIOS .‬ﺑﺮﺍﻱ ﺷﻴﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮏ‬

‫ﻣﺤﻠﻲ ﺑﺎ ﻳﮏ ﺳﮕﻤﻨﺖ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ‪Broadcast Base‬‬ ‫ﺍﺳﺖ ‪ .‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ‪ NetBIOS‬ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻣﻬﺎﻱ ‪ Broadcast‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﻭ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ‬

‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻘﺼﺪ ﭘﻴﺪﺍ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺩﺭ‬ ‫ﻳﮏ ﺷﺒﮑﻪ ﻭ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫‪ ds2000‬ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺎ ﻧﺎﻡ ‪ Exeter‬ﺭﺍ ﺩﺍﺭﺩ‪ .‬ﻳﮏ ﭘﻴﺎﻡ‬

‫‪ Broadcast‬ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﮕﻤﻨﺖ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺗﻤﺎﻣﻲ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﮕﻤﻨﺖ ﻣﮑﻠﻒ ﺑﻪ ﺑﺮﺭﺳﻲ ﭘﻴﺎﻡ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ Exeter‬ﭘﺲ‬ ‫ﺍﺯ ﺩﺭﻳﺎﻓﺖ ﭘﻴﺎﻡ‪ ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ds2000‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺮﺍﻱ ﺑﺮﻃﺮﻑ ﻣﺸﮑﻞ ﺍﺳﺎﻣﻲ )ﺗﺮﺟﻤﻪ‬ ‫ﻧﺎﻡ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﻭ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ( ﺻﺮﻓﺎ" ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﺑﺎ‬ ‫ﺍﺑﻌﺎﺩ ﮐﻮﭼﮏ ﺗﻮﺻﻴﻪ ﺷﺪﻩ ﻭ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮒ ﻧﻈﻴﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺑﺎ ﻣﺎﻫﻴﺖ‬

‫‪ Broadcast Based‬ﺑﺎ ﻣﺸﮑﻼﺕ ﻋﺪﻳﺪﻩ ﺍﻱ ﻣﻮﺍﺟﻪ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺧﻲ ﺍﺯ‬ ‫ﺍﻳﻦ ﻣﺸﮑﻼﺕ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺑﻤﻮﺍﺯﺍﺕ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺗﺮﺍﻓﻴﮏ ﺍﻧﺘﺸﺎﺭ ﺑﺴﺘﻪ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﺸﺪﺕ ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ ) NetBIOS‬ﻧﻈﻴﺮ ‪ (NetBEUI‬ﺩﺍﺭﺍﻱ ﻣﮑﺎﻧﻴﺰﻣﻬﺎﻱ ﻻﺯﻡ‬ ‫ﺑﺮﺍﻱ ﺭﻭﺗﻴﻨﮓ ﻧﺒﻮﺩﻩ ﻭ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺭﻭﺗﻴﻨﮓ ﺩﺭ ﻣﺸﺨﺼﻪ ﻓﺮﻳﻢ ﺑﺴﺘﻪ‬ ‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ‪ NetBIOS‬ﺗﻌﺮﻳﻒ ﻧﺸﺪﻩ ﺍﺳﺖ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻣﮑﺎﻧﻲ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ ﮐﻪ ﻗﺎﺑﻠﻴﺖ ﺭﻭﺗﻴﻨﮓ ﺑﻪ ﭘﻴﺎﻣﻬﺎﻱ ‪NetBIOS‬‬ ‫ﺩﺍﺩﻩ ﺷﻮﺩ ) ﻧﻈﻴﺮ ‪ Overlay‬ﻧﻤﻮﺩﻥ ‪ NetBIOS‬ﺑﺮ ﺭﻭﻱ ﭘﺮﻭﺗﮑﻞ ﺩﻳﮕﺮ ﺑﺎ ﻗﺎﺑﻠﻴﺖ‬

‫ﺭﻭﺗﻴﻨﮓ ‪ ،‬ﺭﻭﺗﺮﻫﺎ ﺑﺼﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﺑﺴﺘﻪ ﻫﺎﻱ ‪ NetBIOS‬ﺭﺍ ﻣﻨﺘﺸﺮ ﻧﺨﻮﺍﻫﻨﺪ‬ ‫ﮐﺮﺩ‪ .‬ﻣﺎﻫﻴﺖ ‪ BroadCast‬ﺑﻮﺩﻥ ﭘﺮﻭﺗﮑﻞ ‪ NetBIOS‬ﻳﮑﻲ ﺍﺯ ﺩﻭ ﻓﺎﮐﺘﻮﺭ ﻣﻬﻢ ﺩﺭ‬

‫ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺧﺼﻮﺻﺎ" ﺩﺭﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮒ ﺍﺳﺖ‪ .‬ﻓﺎﮐﺘﻮﺭ‬ ‫ﺩﻭﻡ ‪ ،‬ﺳﺎﺧﺘﺎﺭ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﻧﺤﻮﻩ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺍﺳﺖ‪ .‬ﺳﺎﺧﺘﺎﺭ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺩﺭ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﻣﺴﻄﺢ )‪ (Flat‬ﺍﺳﺖ‪.‬‬

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‫‪Flat NetBios NameSpace‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﻭ ﺩﺭﮎ ﻣﻠﻤﻮﺱ ﻣﺸﮑﻞ ﻧﺎﻣﮕﺬﺍﺭﻱ ﻣﺴﻄﺢ ﺩﺭ ‪ NetBIOS‬ﻻﺯﻡ‬

‫ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﺜﺎﻝ ﻫﺎﺋﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺫﮐﺮ ﮔﺮﺩﺩ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﻫﺮ ﺷﺨﺺ ﺩﺭ ﺩﻧﻴﺎ ﺩﺍﺭﺍﻱ‬ ‫ﻳﮏ ﻧﺎﻡ ﺑﻮﺩﻩ ﻭ ﺻﺮﻓﺎ" ﺍﺯ ﻃﺮﻳﻖ ﻫﻤﺎﻥ ﻧﺎﻡ ﺷﻨﺎﺧﺘﻪ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﺍﺩﺍﺭﻩ ﺭﺍﻫﻨﻤﺎﺋﻲ‬ ‫ﻭ ﺭﺍﻧﻨﺪﮔﻲ ﺍﻗﺪﺍﻡ ﺑﻪ ﺻﺪﻭﺭ ﮔﻮﺍﻫﻴﻨﻤﺎﻣﻪ ﺭﺍﻧﻨﺪﮔﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻫﺮ ﺭﺍﻧﻨﺪﻩ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﻤﺎﺭﻩ‬

‫ﺳﺮﻳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﺍﺩﺍﺭﻩ ﻓﻮﻕ ﺳﻮﺍﻻﺗﻲ ﻧﻈﻴﺮ ﺳﻮﺍﻻﺕ ﺫﻳﻞ ﻣﻄﺮﺡ ﮔﺮﺩﺩ‬

‫ﻗﻄﻌﺎ" ﭘﺎﺳﺨﮕﻮﺋﻲ ﺑﻪ ﺁﻧﻬﺎ ﺑﺴﺎﺩﮔﻲ ﻣﻴﺴﺮ ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫•‬ ‫•‬

‫ﭼﻨﺪ ﻧﻔﺮ ﺑﺎ ﻧﺎﻡ ﺍﺣﻤﺪ ﺩﺍﺭﺍﻱ ﮔﻮﺍﻫﻴﻨﺎﻣﻪ ﻫﺴﺘﻨﺪ؟‬

‫ﭼﻨﺪ ﻧﻔﺮ ﺑﺎ ﻧﺎﻡ ﺭﺿﺎ ﺩﺍﺭﺍﻱ ﮔﻮﺍﻫﻴﻨﺎﻣﻪ ﻫﺴﺘﻨﺪ؟‬

‫ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﻲ ﺍﮔﺮ ﺍﻓﺴﺮ ﺍﺩﺍﺭﻩ ﺭﺍﻫﻨﻤﺎﺋﻲ ﻭ ﺭﺍﻧﻨﺪﮔﻲ ﺭﺍﻧﻨﺪﻩ ﺍﻱ ﺭﺍ ﺑﺨﺎﻃﺮ ﺗﺨﻠﻒ ﻣﺘﻮﻗﻒ‬ ‫ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﻣﺮﮐﺰ ﻭ ﺑﺮ ﺍﺳﺎﺱ ﻧﺎﻡ ﻭﻱ ﺍﺳﺘﻌﻼﻡ ﻧﻤﺎﻳﺪ ﮐﻪ ﺁﻳﺎ " ﺭﺍﻧﻨﺪﻩ ﺍﻱ ﺑﺎ ﻧﺎﻡ ﺍﺣﻤﺪ ﻗﺒﻼ" ﻧﻴﺰ‬ ‫ﻣﺮﺗﮑﺐ ﺗﺨﻠﻒ ﺷﺪﻩ ﺍﺳﺖ ﻳﺎ ﺧﻴﺮ ؟" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﻃﺮﻑ ﻣﺮﮐﺰ ﺑﻪ ﻭﻱ ﭘﺎﺳﺦ ﻣﺜﺒﺖ ﺩﺍﺩﻩ‬ ‫ﺷﻮﺩ ﺍﻓﺴﺮ ﻣﺮﺑﻮﻃﻪ ﻫﻴﭽﮕﻮﻧﻪ ﺍﻃﻤﻴﻨﺎﻧﻲ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ﮐﻪ ﺭﺍﻧﻨﺪﻩ ﺩﺭ ﻣﻘﺎﺑﻞ ﺁﻥ ﻫﻤﺎﻥ ﺍﺣﻤﺪ‬

‫ﻣﺘﺨﻠﻒ ﺍﺳﺖ ﮐﻪ ﻗﺒﻼ" ﻧﻴﺰ ﺗﺨﻠﻒ ﺩﺍﺷﺘﻪ ﺍﺳﺖ‪.‬‬ ‫ﻳﮑﻲ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ‪ ،‬ﺍﻳﺠﺎﺩ ﺳﻴﺴﺘﻤﻲ ﺍﺳﺖ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺁﻥ ﺍﺭﺍﺋﻪ ﻧﺎﻡ‬

‫ﺑﺼﻮﺭﺕ ﺍﻧﺤﺼﺎﺭﻱ ﻭ ﻏﻴﺮﺗﮑﺮﺍﺭﻱ ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﺍﻓﺮﺍﺩ ﺩﺭ ﺳﻄﺢ ﺩﻧﻴﺎ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ‬ ‫ﺍﻓﺴﺮ ﺍﺩﺍﺭﻩ ﺭﺍﻫﻨﻤﺎﺋﻲ ﻭ ﺭﺍﻧﻨﺪﮔﻲ ﺩﺭ ﺑﺮﺧﻮﺭﺩ ﺑﺎ ﺍﻓﺮﺍﺩ ﻣﺘﺨﻠﻒ ﺩﭼﺎﺭ ﻣﺸﮑﻞ ﻧﺸﺪﻩ ﻭ ﻫﻤﻮﺍﺭﻩ‬ ‫ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ﮐﻪ ﺍﺳﺎﻣﻲ ﺑﺼﻮﺭﺕ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ‬ ‫ﭼﻨﻴﻦ ﺳﻴﺴﺘﻤﻲ ﭼﻪ ﺍﻓﺮﺍﺩ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻧﻬﺎﺋﻲ ﻣﺴﺌﻠﻪ ﻋﺪﻡ ﺗﮑﺮﺍﺭ ﺍﺳﺎﻣﻲ ﺭﺍ ﮐﻨﺘﺮﻝ ﻭ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ‬ ‫ﺭﺍ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺁﻭﺭﻧﺪ ﮐﻪ ﺍﺳﺎﻣﻲ ﺑﺼﻮﺭﺕ ﺗﮑﺮﺍﺭﻱ ﺩﺭ ﺳﻄﺢ ﺩﻧﻴﺎ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ؟‪.‬‬

‫ﺑﻬﺮﺣﺎﻝ ﺳﺎﺧﺘﺎﺭ ﺳﻴﺴﺘﻢ ﻧﺎﻣﮕﺬﺍﺭﻱ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﮕﻮﻧﻪ ﺍﻱ ﺑﺎﺷﺪ ﮐﻪ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺑﻮﺟﻮﺩ‬

‫ﺁﻭﺭﺩ ﮐﻪ ﻧﺎﻡ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﻗﺒﻼ" ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺩﻳﮕﺮﻱ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻧﺸﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﻋﻤﻞ ﭘﻴﺎﺩﻩ‬

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‫ﺳﺎﺯﻱ ﺍﻳﻨﭽﻨﻴﻦ ﺳﻴﺴﺘﻢ ﻫﺎﺋﻲ ﻏﻴﺮ ﻣﻤﮑﻦ ﺍﺳﺖ‪.‬ﻣﺜﺎﻝ ﻓﻮﻕ ﻣﺤﺪﻭﺩﻳﺖ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺑﺼﻮﺭﺕ‬

‫ﻣﺴﻄﺢ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺳﻴﺴﺘﻢ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺑﺮ ﺍﺳﺎﺱ ‪ NetBIOS‬ﺑﺼﻮﺭﺕ ﻣﺴﻄﺢ ﺑﻮﺩﻩ ﻭ ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ‬ ‫ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻳﮏ ﻧﺎﻡ ﻣﺘﻤﺎﻳﺰ ﺍﺯ ﺩﻳﮕﺮﺍﻥ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ‬ ‫ﮐﻪ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ NetBIOS‬ﺩﺍﺭﺍﻱ ﺍﺳﺎﻣﻲ ﻳﮑﺴﺎﻧﻲ‬

‫ﺑﺎﺷﻨﺪ ﭘﻴﺎﻣﻬﺎﻱ ﺍﺭﺳﺎﻟﻲ ﺍﺯ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﮐﻪ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﻧﻤﻮﻧﻪ )ﻧﺎﻡ‬ ‫ﺗﮑﺮﺍﺭﻱ( ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪ ،‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺑﺮﻭﺯ ﻣﺸﮑﻼﺕ ﺩﺭ ﺷﺒﮑﻪ ﻭ ﻋﺪﻡ ﺭﺳﻴﺪﻥ ﭘﻴﺎﻡ‬ ‫ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺑﻪ ﻣﻘﺼﺪ ﺩﺭﺳﺖ ﺧﻮﺩ ﺑﺎﺷﺪ‪.‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪ NetBIOS‬ﻭ ‪WinSock‬‬ ‫‪ DNS‬ﻣﺴﺎﺋﻞ ﻓﻮﻕ ﺭﺍ ﺑﺴﺎﺩﮔﻲ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﺍﺯ ﻳﮏ ﻣﺪﻝ‬ ‫ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺑﺮﺍﻱ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﺍﺳﺖ ‪ .‬ﻗﺒﻞ ﺍﺯ ﭘﺮﺩﺍﺧﺘﻦ ﺑﻪ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﻭ‬ ‫ﺟﺰﺋﻴﺎﺕ ﺳﻴﺴﺘﻢ ‪ DNS‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﻧﺤﻮﻩ ﺩﺳﺘﻴﺎﺑﻲ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ‬

‫ﺷﺒﮑﻪ ﻭ ﺧﺼﻮﺻﺎ" ﻧﺤﻮﻩ ﺍﺭﺗﺒﺎﻁ ﺁﻧﻬﺎ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪.‬‬ ‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺑﺎ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ‪ ،‬ﺑﺎ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪.‬‬ ‫•‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﺳﻮﮐﺖ ﻫﺎﻱ ﻭﻳﻨﺪﻭﺯ )‪(WinSock‬‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ‪NetBIOS‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﻳﮑﻲ ﺍﺯ ﻣﺴﺎﺋﻞ ﺍﺳﺎﺳﻲ ﺩﺭ ﻧﺎﻣﮕﺬﺍﺭﻱ ﻭ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﻣﺒﺘﻨﻲ ﺑﺮ ‪ TCP/IP‬ﺭﺍ ﺑﻪ ﭼﺎﻟﺶ ﻣﻲ ﮐﺸﺎﻧﻨﺪ‪.‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﮐﻪ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫‪ NetBIOS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﺍﺯ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﻌﻨﻮﺍﻥ " ﻧﻘﻄﻪ ﺁﺧﺮ" ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻃﺎﺕ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ NetBIOS‬ﺻﺮﻓﺎ" ﻣﺮﺍﻗﺒﺖ ﻫﺎﻱ ﻻﺯﻡ ﺭﺍ‬ ‫ﺩﺭ ﺧﺼﻮﺹ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ‪ session‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪ .‬ﺩﺭ‬

‫ﺣﺎﻟﻴﮑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ (TCP/IP )IP,TCP‬ﻫﻴﭽﮕﻮﻧﻪ ﺁﮔﺎﻫﻲ ﺍﺯ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫‪206‬‬

‫‪ NetBIOS‬ﻧﺪﺍﺷﺘﻪ ﻭ ﺩﺭ ﺗﻤﺎﻣﻲ ﻣﻮﺍﺭﺩ ﻣﺮﺍﻗﺒﺖ ﻫﺎﻱ ﻻﺯﻡ ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﺨﻮﺍﻫﻨﺪ ﺩﺍﺩ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ) ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ‪ NetBIOS‬ﺑﮑﻤﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪NetBIOS‬‬ ‫ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻣﺮﺗﺒﻂ ﺧﻮﺍﻫﻨﺪ ﺷﺪ( ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ netBT‬ﻭ ﻳﺎ ‪NetBIOS over‬‬

‫‪ TCP/IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻳﮏ ﻣﻨﺒﻊ ﺩﺭ ﺷﺒﮑﻪ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﻳﮏ ﺑﺮﻧﺎﻣﻪ ﺑﺎ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ NetBIOS‬ﺍﺭﺍﺋﻪ ﻣﻲ ﮔﺮﺩﺩ ﻭ ﺑﻪ ﻻﻳﻪ ‪Application‬‬

‫ﻣﻲ ﺭﺳﺪ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ NetBT‬ﺑﺎ ﺁﻥ ﻣﺮﺗﺒﻂ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﻧﺎﻡ‬ ‫‪ NetBIOS‬ﺗﺮﺟﻤﻪ ﻭ ﺑﻪ ﻳﮏ ‪ IP‬ﺗﺒﺪﻳﻞ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻧﺎﻡ ‪ NetBIOS‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ‬ ‫ﻳﮏ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﺗﺮﺟﻤﻪ ﻣﻲ ﮔﺮﺩﺩ ﺩﺭﺧﻮﺍﺳﺖ ﻣﺮﺑﻮﻃﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﻻﻳﻪ ﻫﺎﻱ ﺯﻳﺮﻳﻦ‬

‫ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺭﺍ ﻃﻲ ﺗﺎ ﻭﻇﺎﻳﻒ ﻣﺤﻮﻟﻪ ﺩﻧﺒﺎﻝ ﮔﺮﺩﺩ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ‬ ‫ﻓﻮﻕ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ‪Winsock‬‬

‫ﺍﻏﻠﺐ ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﮐﻪ ﺑﺮﺍﺳﺎﺱ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻧﻮﺷﺘﻪ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪ ،‬ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ‬

‫‪ Winsock‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﻧﻴﺎﺯﻣﻨﺪ ﺁﮔﺎﻫﻲ ﺍﺯ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ‬ ‫ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﻧﺒﻮﺩﻩ ﻭ ﺑﺎ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘــﺼﺪ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳـﺠﺎﺩ ﻳﮏ ﺍﺭﺗــﺒﺎﻁ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬

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‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺟﻬﺖ ﮐﺎﺭ ﺑﺎ ﺍﻋﺪﺍﺩ ) ﺧﺼﻮﺻﺎ" ‪ ( IP‬ﺩﺍﺭﺍﻱ ﻣﺴﺎﺋﻞ ﻭ ﻣﺸﮑﻼﺕ ﺑﺴﻴﺎﺭ ﻧﺎﭼﻴﺰﻱ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻧﺴﺎﻥ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺩﺍﺭﺍﻱ ﻣﺸﮑﻼﺕ ﺧﺎﺹ ﺧﻮﺩ ﺍﺳﺖ ‪ .‬ﻗﻄﻌﺎ"‬ ‫ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺍﻋﺪﺍﺩ ﺑﺰﺭﮒ ﻭ ﻃﻮﻻﻧﻲ ﺑﺮﺍﻱ ﻫﺮ ﺷﺨﺺ ﮐﺎﺭ ﻣﺸﮑﻠﻲ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﻣﺎ ﻃﻲ ﺭﻭﺯ ﺑﻪ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﻣﺮﺍﺟﻌﻪ ﻭ ﺻﺮﻓﺎ" ﺑﺎ ﺗﺎﻳﭗ ﺁﺩﺭﺱ ﻣﺮﺑﻮﻃﻪ ﮐﻪ‬ ‫ﺑﺼﻮﺭﺕ ﻳﮏ ﻧﺎﻡ ﺧﺎﺹ ﺍﺳﺖ )‪ (www.test.com‬ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﺳﺎﻳﺖ ﻣﺮﺑﻮﻃﻪ ﺑﻬﺮﻩ ﻣﻨﺪ‬

‫ﻣﻲ ﮔﺮﺩﻳﻢ‪ .‬ﺁﻳﺎ ﻃﻲ ﺍﻳﻦ ﻧﻮﻉ ﻣﻼﻗﺎﺕ ﻫﺎ ﻣﺎ ﻧﻴﺎﺯﻣﻨﺪ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﻣﺮﺑﻮﻃﻪ ﺑﻮﺩﻩ‬ ‫ﺍﻳﻢ؟ ﺑﻬﺮﺣﺎﻝ ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻤﺮﺍﺗﺐ ﺭﺍﺣﺖ ﺗﺮ ﺍﺯ ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺍﻋﺪﺍﺩ‬ ‫) ﮐﺪ ( ﺍﺳﺖ‪ .‬ﺍﺯ ﺁﻧﺠﺎﺋﻴﮑﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ Winsock‬ﻧﻴﺎﺯﻣﻨﺪ ﺁﮔﺎﻫﻲ ﺍﺯ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ‬

‫‪ Host Name‬ﻧﻤﻲ ﺑﺎﺷﻨﺪ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺭﻋﺎﻳﺖ ﺗﻤﺎﻣﻲ ﻣﺴﺎﺋﻞ ﺟﺎﻧﺒﻲ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﺑﺮﺍﻱ‬ ‫ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺭﺍ ﺗﺮﺟﻤﻪ‬

‫ﺍﺳﺎﻣﻲ)‪Name Resoulation‬‬

‫‪(Host‬‬

‫ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬ ‫ﻣﻮﺍﺭﺩ ﺍﺧﺘﻼﻑ ﺑﻴﻦ ‪ NetBIOS‬ﻭ ‪WinSock‬‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ NetBIOS‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺒﻞ ﺍﺯ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﻧﺎﻡ‬

‫‪ NetBIOS‬ﺭﺍ ﺑﻪ ﻳﮏ ‪ IP‬ﺗﺮﺟﻤﻪ ﻧﻤﺎﻳﻨﺪ‪ ).‬ﻗﺒﻞ ﺍﺯ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﻧﺎﻡ ‪ NetBIOS‬ﺑﻪ ‪IP‬‬ ‫ﺗﺒﺪﻳﻞ ﺧﻮﺍﻫﺪ ﺷﺪ‪ (.‬ﺩﺭ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ WinSock‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻧﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮ ) ‪Host‬‬

‫‪ (name‬ﺩﺭ ﻣﻘﺎﺑﻞ ‪ IP‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﻗﺒﻞ ﺍﺯ ﻋﺮﺿﻪ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﺗﻤﺎﻣﻲ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺗﻮﺳﻂ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ ﻭﻳﻨﺪﻭﺯ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﺷﺪﻧﺪ ﺍﺯ ‪NetBIOS‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﺮﺩﻧﺪ‪ .‬ﺑﻬﻤﻴﻦ ﺩﻟﻴﻞ ﺩﺭ ﮔﺬﺷﺘﻪ ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ ﺻﺮﻑ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﻣﻲ ﮔﺮﺩﻳﺪ‪.‬‬ ‫ﻭﻳﻨﺪﻭﺯ ﻭﺍﺑﺴﺘﮕﻲ ﺑﻪ ‪ NetBIOS‬ﻧﺪﺍﺷﺘﻪ ﻭ ﺩﺭ ﻣﻘﺎﺑﻞ ﺍﺯ ﺳﻴﺴﺘﻢ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪DNS NameSpace‬‬ ‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ ‪ DNS‬ﺍﺯ ﻳﮏ ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺑﺮﺍﻱ ﺳﻴﺴﺘﻢ‬ ‫ﻧﺎﻣﮕﺬﺍﺭﻱ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪208‬‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺑﻮﺩﻥ ﺳﺎﺧﺘﺎﺭ ﻓﻮﻕ‪ ،‬ﭼﻨﺪﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺩﺍﺭﺍﻱ‬

‫ﺍﺳﺎﻣﻲ ﻳﮑﺴﺎﻥ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﻭ ﻫﻴﭽﮕﻮﻧﻪ ﻧﮕﺮﺍﻧﻲ ﺍﺯ ﻋﺪﻡ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﻫﺎ ﻭﺟﻮﺩ‬ ‫ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺩﺭﺳﺖ ﻧﻘﻄﻪ ﻣﺨﺎﻟﻒ ﺳﻴﺴﺘﻢ ﻧﺎﻣﮕﺬﺍﺭﻱ ‪ NetBIOS‬ﺍﺳﺖ‪.‬‬ ‫ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺘﺨﺎﺏ ﺩﻭ ﻧﺎﻡ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ‬

‫ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ ﻳﮑﺴﺎﻥ ﻧﺨﻮﺍﻫﻴﻢ ﻧﺒﻮﺩ‪.‬‬

‫ﺑﺎﻻﺗﺮﻳﻦ ﺳﻄﺢ ﺩﺭ ‪ DNS‬ﺑﺎ ﻧﺎﻡ ‪ Root Domain‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ﻳﮏ “‪”.‬‬ ‫ﻭ ﻳﺎ ﻳﮏ ﻓﻀﺎﻱ ﺧﺎﻟﻲ “” ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﻼﻓﺎﺻﻠﻪ ﭘﺲ ﺍﺯ ﺭﻳﺸﻪ ﺑﺎ ﺍﺳﺎﻣﻲ ﻣﻮﺟﻮﺩ ﺩﺭ‬

‫ﺩﺍﻣﻨﻪ ﺑﺎﻻﺗﺮﻳﻦ ﺳﻄﺢ )‪ (Top Level‬ﺑﺮﺧﻮﺭﺩ ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ‪ .‬ﺩﺍﻣﻨﻪ ﻫﺎﻱ ‪Com , .net , .‬‬

‫‪ .org , .edu‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺳﺎﺯﻣﺎﻧﻬﺎﺋﻲ ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺩﺍﺷﺘﻦ ﻳﮏ‬ ‫ﻭﺏ ﺳﺎﻳﺖ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺍﺭﻧﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻳﮏ ﺩﺍﻣﻨﻪ ﺭﺍ ﮐﻪ ﺑﻌﻨﻮﺍﻥ ﻋﻀﻮﻱ ﺍﺯ ﺍﺳﺎﻣﻲ‬ ‫ﺣﻮﺯﻩ ‪ Top Level‬ﻣﻲ ﺑﺎﺷﺪ ﺭﺍ ﺑﺮﺍﻱ ﺧﻮﺩ ﺍﺧﺘﻴﺎﺭ ﻧﻤﺎﻳﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﺣﻮﺯﻩ ﻫﺎﻱ ﺳﻄﺢ ﺑﺎﻻ‬

‫ﺩﺍﺭﺍﻱ ﮐﺎﺭﺑﺮﺩﻫﺎﻱ ﺧﺎﺻﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﺳﺎﺯﻣﺎﻥ ﻫﺎﻱ ﺍﻗﺘﺼﺎﺩﻱ ﺩﺭ ﺣﻮﺯﻩ‪ com .‬ﻭ‬ ‫ﻣﻮﺳﺴﺎﺕ ﺁﻣﻮﺯﺷﻲ ﺩﺭ ﺣﻮﺯﻩ ‪ edu.‬ﻭ ‪ domain ...‬ﺧﻮﺩ ﺭﺍ ﺛﺒﺖ ﺧﻮﺍﻫﻨﺪ ﻧﻤﻮﺩ‪.‬ﺷﮑﻞ ﺯﻳﺮ‬ ‫ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ‪ DNS‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺩﺭ ﻫﺮ ﺳﻄﺢ ﺍﺯ ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﻓﻮﻕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺳﺎﻣﻲ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺘﻔﺎﻭﺕ ﺑﺎﺷﺪ‪.‬‬

‫ﻣﺜﻼ" ﻧﻤﻲ ﺗﻮﺍﻥ ﺩﻭ ﺣﻮﺯﻩ ‪ com.‬ﻭ ﻳﺎ ﺩﻭ ﺣﻮﺯﻩ ‪ net.‬ﺭﺍ ﺗﻌﺮﻳﻒ ﻭ ﻳﺎ ﺩﻭ ﺣﻮﺯﻩ‬

‫‪ Microsoft.com‬ﺩﺭ ﺳﻄﺢ ﺩﻭﻡ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ‪.‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺳﺎﻣﻲ ﺗﮑﺮﺍﺭﻱ ﺩﺭ ﺳﻄﻮﺡ‬

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‫ﻣﺘﻔﺎﻭﺕ ﻣﺠﺎﺯ ﺑﻮﺩﻩ ﻭ ﺑﻬﻤﻴﻦ ﺩﻟﻴﻞ ﺍﺳﺖ ﮐﻪ ﺍﻏﻠﺐ ﻭﺏ ﺳﺎﻳﺖ ﻫﺎ ﺩﺍﺭﺍﻱ ﻧﺎﻡ ‪www‬‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺣﻮﺯﻩ ﻫﺎﻱ ‪ Top Level‬ﻭ ‪ Second level‬ﺗﻨﻬﺎ ﺑﺨﺸﻬﺎﺋﻲ ﺍﺯ ﺳﻴﺴﺘﻢ ‪ DNS‬ﻣﻲ ﺑﺎﺷﻨﺪ‬ ‫ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺼﻮﺭﺕ ﻣﺮﮐﺰﻱ ﻣﺪﻳﺮﻳﺖ ﻭ ﮐﻨﺘﺮﻝ ﮔﺮﺩﻧﻨﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩﻥ ﺩﺍﻣﻨﻪ‬

‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺳﺎﺯﻣﺎﻥ ﻭ ﻳﺎ ﺷﺮﮐﺘﻲ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩﻥ ﺭﺍ ﺑﺮﻋﻬﺪﻩ‬ ‫ﺩﺍﺭﺩ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﺁﻧﻬﺎ ﺩﺭﺧﻮﺍﺳﺖ ﻧﻤﻮﺩ ﮐﻪ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩﻥ‬ ‫ﺩﺍﻣﻨﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﺎ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪ .‬ﺩﺭ ﮔﺬﺷﺘﻪ ﺗﻨﻬﺎ ﺳﺎﺯﻣﺎﻧﻲ ﮐﻪ ﺩﺍﺭﺍﻱ ﻣﺠﻮﺯ ﻻﺯﻡ ﺑﺮﺍﻱ‬

‫ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩﻥ ﺣﻮﺯﻩ ﻫﺎﻱ ﺳﻄﺢ ﺩﻭﻡ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺩﺍﺷﺖ ﺷﺮﮐﺖ ‪NSI)Network‬‬ ‫‪ (Solutions Intcorporated‬ﺑﻮﺩ‪ .‬ﺍﻣﺮﻭﺯﻩ ﺍﻣﺘﻴﺎﺯ ﻓﻮﻕ ﺻﺮﻓﺎ" ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺷﺮﮐﺖ ﻓﻮﻕ‬ ‫ﻧﺒﻮﺩﻩ ﻭ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﻗﺪﺍﻡ ﺑﻪ ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩﻥ ﺣﻮﺯﻩ ﻫﺎ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻣﺸﺨﺼﺎﺕ ﺩﺍﻣﻨﻪ ﻭ ﺍﺳﻢ ‪Host‬‬

‫ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ‪ DNS‬ﺑﻌﻨﻮﺍﻥ ﻋﻀﻮﻱ ﺍﺯ ﻳﮏ ﺩﺍﻣﻨﻪ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺷﻨﺎﺧﺖ ﻭ ﺿﺮﻭﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺑﻬﻤﺮﺍﻩ ‪ DNS‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ‬ ‫‪ FQDN‬ﺁﺷﻨﺎ ﺷﻮﻳﻢ ‪.‬‬ ‫ﻣﻌﺮﻓﻲ ‪(Qualified Domain Names FQDN)Fully‬‬ ‫ﻳﮏ ‪ FQDN‬ﻣﺤﻞ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﺎﺹ ﺭﺍ ﺩﺭ ‪ DNS‬ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﻧﻤﻮﺩ‪ .‬ﺑﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ FQDN‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺴﺎﺩﮔﻲ ﻣﺤﻞ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺩﺍﻣﻨﻪ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻣﺸﺨﺺ ﻭ ﺑﻪ ﺁﻥ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﻧﻤﻮﺩ‪ FQDN .‬ﻳﮏ ﻧﺎﻡ ﺗﺮﮐﻴﺒﻲ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺁﻥ ﻧﺎﻡ ﻣﺎﺷﻴﻦ )‪ (Host‬ﻭ ﻧﺎﻡ ﺩﺍﻣﻨﻪ‬ ‫ﻣﺮﺑﻮﻃﻪ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ ‪ .‬ﻣﺜﻼ" ﺍﮔﺮ ﺷﺮﮐﺘﻲ ﺑﺎ ﻧﺎﻡ ‪ TestCorp‬ﺩﺭ ﺣﻮﺯﻩ ﺳﻄﺢ ﺩﻭﻡ‬ ‫ﺩﺍﻣﻨﻪ ﺧﻮﺩ ﺭﺍ ﺛﺒﺖ ﻧﻤﺎﻳﺪ )‪ (TestCorp.com‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺑﺮ‬

‫ﺭﻭﻱ ‪ TestCorp.com‬ﺍﺟﺮﺍﺀ ﮔﺮﺩﺩ ﻣﻲ ﺗﻮﺍﻥ ﺁﻥ ﺭﺍ ‪ www‬ﻧﺎﻣﻴﺪ ﻭ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ‪ www.testCorp.com‬ﺑﻪ ﺁﻥ ﺩﺳﺘﻴﺎﺑﻲ ﭘﻴﺪﺍ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫‪210‬‬

‫ﺩﻗﺖ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ﮐﻪ ‪ www‬ﺍﺯ ﻧﺎﻡ ‪ FQDN‬ﻣﺜﺎﻝ ﻓﻮﻕ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﻳﮏ ﺷﻨﺎﺳﻪ ﺧﺪﻣﺎﺗﻲ‬

‫ﻧﺒﻮﺩﻩ ﻭ ﺻﺮﻓﺎ" ﻧﺎﻡ ‪ host‬ﻣﺮﺑﻮﻁ ﺑﻪ ﻣﺎﺷﻴﻦ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻳﮏ ﻧﺎﻡ‬ ‫‪ FQDN‬ﺍﺯ ﺩﻭ ﻋﻨﺼﺮ ﺍﺳﺎﺳﻲ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫‪ : Label‬ﺷﺎﻣﻞ ﻧﺎﻡ ﺣﻮﺯﻩ ﻭ ﻳﺎ ﻧﺎﻡ ﻳﮏ ‪ host‬ﺍﺳﺖ‪.‬‬

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‫‪ : Dots‬ﻧﻘﻄﻪ ﻫﺎ ﮐﻪ ﺑﺎﻋﺖ ﺟﺪﺍﺳﺎﺯﻱ ﺑﺨﺶ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻫﺮ ‪ lable‬ﺗﻮﺳﻂ ﻧﻘﻄﻪ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﺟﺪﺍ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﻫﺮ ‪ lable‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺣﺪﺍﮐﺜﺮ ﺩﺍﺭﺍﻱ‬ ‫‪ ۶۳‬ﺑﺎﻳﺖ ﺑﺎﺷﺪ‪ .‬ﺩﻗﺖ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ﮐﻪ ﻃﻮﻝ ) ﺍﻧﺪﺍﺯﻩ ( ﻫﺮ ‪ lable‬ﺑﺮ ﺣﺴﺐ ﺑﺎﻳﺖ ﻣﺸﺨﺺ‬ ‫ﺷﺪﻩ ﺍﺳﺖ ﻧﻪ ﺑﺮ ﺣﺴﺐ ﻃﻮﻝ ﺭﺷﺘﻪ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﺳﺖ ﮐﻪ ‪ DNS‬ﺩﺭ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﺍﺯ‬

‫ﮐﺎﺭﺍﮐﺘﺮﻫﺎﻱ ‪ UTF-8‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺮ ﺧﻼﻑ ﮐﺎﺭﺍﮐﺘﺮﻫﺎﻱ ﺍﺳﮑﻲ ﮐﻪ ﻗﺒﻼ" ﺍﺯ ﺁﻧﺎﻥ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﺑﻬﺮﺣﺎﻝ ‪ FQDN‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻃﻮﻟﻲ ﺑﻪ ﺍﻧﺪﺍﺯﻩ ﺣﺪﺍﮐﺜﺮ ‪ ٢٥٥‬ﺑﺎﻳﺖ‬ ‫ﺑﺎﺷﺪ‪.‬‬

‫ﻃﺮﺍﺣﻲ ﻧﺎﻡ ﺣﻮﺯﻩ ﺑﺮﺍﻱ ﻳﮏ ﺳﺎﺯﻣﺎﻥ‬ ‫ﻗﺒﻞ ﺍﺯ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺳﻴﺴﺘﻢ ) ﻣﺪﻝ ( ‪ DNS‬ﺑﺮﺍﻱ ﻳﮏ ﺳﺎﺯﻣﺎﻥ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﻧﻤﻮﻧﻪ‬

‫ﺳﻮﺍﻻﺕ ﺫﻳﻞ ﺑﺪﺭﺳﺘﻲ ﭘﺎﺳﺦ ﺩﺍﺩ‪:‬‬ ‫•‬

‫ﺁﻳﺎ ﺳﺎﺯﻣﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺍﻳﻨﺘﺮﺍﻧﺘﻲ ﺧﻮﺩ ﺍﺯ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ؟‬

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‫ﺁﻳﺎ ﺳﺎﺯﻣﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺳﺎﻳﺖ ﺍﻳﻨﺘﺮﻧﺘﻲ ﺍﺳﺖ؟‬

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‫ﺁﻳﺎ ﺳﺎﺯﻣﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺣﻮﺯﻩ) ﺩﺍﻣﻨﻪ ( ﺛﺒﺖ ﺷﺪﻩ ) ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ( ﺍﺳﺖ؟‬

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‫ﺁﻳﺎ ﺳﺎﺯﻣﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺍﺯ ﺍﺳﺎﻣﻲ ﺣﻮﺯﻩ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ ﻣﻨﺎﺑﻊ ﻣﺮﺑﻮﻃﻪ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ‬

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‫ﺍﻳﻨﺘﺮﻧﺖ ‪ /‬ﺍﻳﻨﺘﺮﺍﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ؟‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺎﻡ ﻳﮑﺴﺎﻥ ﺩﺍﻣﻨﻪ ﺑﺮﺍﻱ ﻣﻨﺎﺑﻊ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﻳﻨﺘﺮﺍﻧﺖ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺳﺎﻣﻲ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ ﻧﺎﻣﮕﺬﺍﺭﻱ ﺩﺍﻣﻨﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ‬

‫ﺩﺍﺧﻠﻲ ﻭ ﻣﻨﺎﺑﻊ ﺍﻳﻨﺘﺮﻧﺘﻲ ﺩﺭ ﻣﺮﺣﻠﻪ ﺍﻭﻝ ﺑﺴﻴﺎﺭ ﻗﺎﺑﻞ ﺗﻮﺟﻪ ﻭ ﺟﺬﺍﺏ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺗﻤﺎﻣﻲ‬

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‫ﻣﺎﺷﻴﻦ ﻫﺎ ﺑﻌﻨﻮﺍﻥ ﻋﻀﻮ ﻳﮏ ﺩﺍﻣﻨﻪ ﻳﮑﺴﺎﻥ ﻣﺤﺴﻮﺏ ﻭ ﮐﺎﺭﺑﺮﺍﻥ ﻧﻴﺎﺯ ﺑﻪ ﺑﺨﺎﻃﺮ ﺳﭙﺮﺩﻥ ﺩﺍﻣﻨﻪ‬ ‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺑﺮ ﺍﺳﺎﺱ ﻧﻮﻉ ﻣﻨﺒﻊ ﮐﻪ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺍﺧﻠﻲ ﻭ ﻳﺎ ﺧﺎﺭﺟﻲ ﺑﺎﺷﺪ ﻧﺨﻮﺍﻫﻨﺪ‬

‫ﺩﺍﺷﺖ ‪..‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﺟﻮﺩ ﻣﺰﺍﻳﺎﻱ ﻓﻮﻕ‪ ،‬ﺑﮑﺎﺭﮔﻴﺮﻱ ﺍﻳﻦ ﺭﻭﺵ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺑﺮﻭﺯ ﺑﺮﺧﻲ‬ ‫ﻣﺸﮑﻼﺕ ﻧﻴﺰ ﮔﺮﺩﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻔﺎﻇﺖ ﺍﺯ ﻧﺎﺣﻴﻪ )‪ (Zone‬ﻫﺎﻱ ‪ DNS‬ﺍﺯ ﺩﺳﺘﻴﺎﺑﻲ ﻏﻴﺮ‬

‫ﻣﺠﺎﺯ ﻧﻤﻲ ﺑﺎﻳﺴﺖ ﻫﻴﭽﮕﻮﻧﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﻨﺎﺑﻊ ﺩﺍﺧﻠﻲ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫‪ DNS‬ﻧﮕﻬﺪﺍﺭﻱ ﻧﻤﻮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮﺍﻱ ﻳﮏ ﺩﺍﻣﻨﻪ ﺍﺯ ﺩﻭ ‪ Zone‬ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻧﻤﻮﺩ‪ .‬ﻳﮑﻲ ﺍﺯ ‪ Zone‬ﻫﺎ ﻣﻨﺎﺑﻊ ﺩﺍﺧﻠﻲ ﺭﺍ ﺩﻧﺒﺎﻝ ﻭ ‪ Zone‬ﺩﻳﮕﺮ ﻣﺴﺌﻮﻟﻴﺖ ﭘﺎﺳﺨﮕﻮﺋﻲ ﺑﻪ‬

‫ﻣﻨﺎﺑﻌﻲ ﺍﺳﺖ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﻗﻄﻌﺎ" ﺣﺠﻢ ﻭﻇﺎﻳﻒ ﻣﺪﻳﺮﻳﺖ‬ ‫ﺳﺎﻳﺖ ﺭﺍ‬

‫ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻧﺎﻡ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ ﻣﻨﺎﺑﻊ ﺩﺍﺧﻠﻲ ﻭ ﺧﺎﺭﺟﻲ‬

‫ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻋﻤﻠﻴﺎﺗﻲ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺯﻣﺎﻥ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ‬

‫ﻣﻨﺎﺑﻊ ﺩﺍﺧﻠﻲ ﻭ ﺧﺎﺭﺟﻲ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ ﺩﺍﺭﺩ ‪ Mirror‬ﻧﻤﻮﺩﻥ ﻣﻨﺎﺑﻊ ﺧﺎﺭﺟﻲ ﺑﺼﻮﺭﺕ‬ ‫ﺩﺍﺧﻠﻲ ﺍﺳﺖ‪ .‬ﻣﺜﻼ" ﻓﺮﺽ ﻧﻤﺎﺋﻴﺪ ﮐﻪ ‪ Test.com‬ﻧﺎﻡ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻊ‬

‫ﺩﺍﺧﻠﻲ ) ﺍﻳﻨﺘﺮﺍﻧﺖ( ﻭ ﻣﻨﺎﺑﻊ ﺧﺎﺭﺟﻲ ) ﺍﻳﻨﺘﺮﻧﺖ ( ﺍﺳﺖ‪.‬ﺩﺭﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﺩﺍﺭﺍﻱ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﻭﺏ ﺑﺮﺍ ﻳﺎﻳﻨﺘﺮﺍﻧﺖ ﺑﺎﺷﻴﻢ ﮐﻪ ﭘﺮﺳﻨﻞ ﺳﺎﺯﻣﺎﻥ ﺍﺯ ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺍﺧﺘﺼﺎﺻﻲ ﻭ ﺳﺎﻳﺮ ﺍﻃﻼﻋﺎﺕ ﺩﺍﺧﻠﻲ ﺳﺎﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ ﺩﺍﺭﺍﻱ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻧﻲ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ ﮐﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻊ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻮﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻗﺮﺍﺭ‬ ‫ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪ .‬ﻣﺎ ﻣﻲ ﺧﻮﺍﻫﻴﻢ ﺍﺯ ﺍﺳﺎﻣﻲ ﻳﮑﺴﺎﻥ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﺋﻴﻢ‪.‬‬ ‫ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﺍﮔﺮ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ ‪ www.test.com‬ﺻﻮﺭﺕ ﭘﺬﻳﺮﺩ ﻣﺴﺌﻠﻪ ﺑﻪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺧﺘﻢ ﺧﻮﺍﻫﺪ ﺷﺪ ﮐﻪ ﻗﺼﺪ ﺩﺍﺭﻳﻢ ﺑﺮﺍﻱ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ‬

‫ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﻣﺎ ﻧﻤﻲ ﺧﻮﺍﻫﻴﻢ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺎﺩﺭ ﺑﻪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﺷﺨﺼﻲ ﻭ‬ ‫ﺩﺍﺧﻠﻲ ﺳﺎﺯﻣﺎﻥ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪212‬‬

‫ﺟﻬﺖ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ ‪ Mirror‬ﻧﻤﻮﺩﻥ ﻣﻨﺎﺑﻊ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺼﻮﺭﺕ ﺩﺍﺧﻠﻲ ﺍﺳﺖ ﻭ ﺍﻳﺠﺎﺩ ﻳﮏ‬

‫‪ zone‬ﺩﺭ ‪ DNS‬ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﮐﺎﺭﺑﺮﺍﻥ ﺑﻪ ﻣﻨﺎﺑﻊ ﺩﺍﺧﻠﻲ ﺿﺮﻭﺭﻱ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ‬

‫ﮐﺎﺭﺑﺮﻱ ﺩﺭﺧﻮﺍﺳﺖ ‪ www.test.com‬ﺭﺍ ﺻﺎﺩﺭ ﻧﻤﺎﺋﻴﺪ ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﺴﺌﻠﻪ ﻧﺎﻡ ﺍﺯ ﻃﺮﻳﻖ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺍﺧﻠﻲ ‪ DNS‬ﺑﺮﻃﺮﻑ ﺧﻮﺍﻫﺪ ﺷﺪ ﮐﻪ ﺷﺎﻣﻞ ‪ zone‬ﺩﺍﺧﻠﻲ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ‪.‬‬

‫ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﮐﺎﺭﺑﺮ ﺍﻳﻨﺘﺮﻧﺖ ﻗﺼﺪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ‪ www.test.com‬ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﻭﻱ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﻳﻨﺘﺮﻧﺖ ‪ DNS‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪﺷﺪ ﮐﻪ ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ‬

‫ﺁﺩﺭﺱ ‪ IP‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺧﺎﺭﺟﻲ ‪ DNS‬ﺑﺮﮔﺮﺩﺍﻧﺪﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺳﺎﻣﻲ ﻣﺘﻔﺎﻭﺕ ﺑﺮﺍﻱ ﺩﺍﻣﻨﻪ ﻫﺎ ﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﻳﻨﺘﺮﺍﻧﺖ‬

‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺎﺯﻣﺎﻧﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻭ ﻳﺎ ﺩﺭ ﺣﺎﻝ ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﺟﻬﺖ ﺍﺗﺼﺎﻝ ﺑﻪ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺩﻭ ﻧﺎﻡ ﻣﺘﻔﺎﻭﺕ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻊ ﺍﻳﻨﺘﺮﺍﻧﺘﻲ ﻭ ﺍﻳﻨﺘﺮﻧﺘﻲ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﺪﻝ ﻓﻮﻕ ﺑﻤﺮﺍﺗﺐ ﺍﺯ ﻣﺪﻝ ﻗﺒﻞ ﺳﺎﺩﻩ ﺗﺮ ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‬ ‫ﻧﻴﺎﺯﻱ ﺑﻪ ﻧﮕﻬﺪﺍﺭﻱ ‪ Zone‬ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﻬﺎ ﻧﺒﻮﺩﻩ ﻭ ﻫﺮﻳﮏ ﺍﺯ ﺁﻧﻬﺎ ﺩﺍﺭﺍﻱ‬ ‫ﻳﮏ ﻧﺎﻡ ﻣﺠﺰﺍ ﻭ ﺍﺧﺘﺼﺎﺻﻲ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﻧﺎﻡ ﺍﻳﻨﺘﺮﻧﺘﻲ ﺣﻮﺯﻩ‬ ‫ﺭﺍ ‪ Test.com‬ﻭ ﻧﺎﻡ ﺍﻳﻨﺘﺮﺍﻧﺘﻲ ﺁﻥ ﺭﺍ ‪ TestCorp.com‬ﻗﺮﺍﺭ ﺩﺍﺩ‪.‬‬

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‫ﺑﺮﺍﻱ ﻧﺎﻣﮕﺬﺍﺭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺯﻳﺮ ﺩﺍﻣﻨﻪ ﻫﺎ ﻣﻲ ﺗﻮﺍﻥ ﺍﺳﺎﻣﻲ ﺍﻧﺘﺨﺎﺑﻲ ﺭﺍ ﺑﺮﺍﺳﺎﺱ ﻧﻮﻉ ﻓﻌﺎﻟﻴﺖ ﻭ‬ ‫ﻳﺎ ﺣﻮﺯﻩ ﺟﻔﺮﺍﻓﻴﺎﺋﻲ ﺍﻧﺘﺨﺎﺏ ﻧﻤﻮﺩ‪.‬‬ ‫‪Zones of Authority‬‬ ‫‪ DNS‬ﺩﺍﺭﺍﻱ ﺳﺎﺧﺘﺎﺭﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﺮﺍﻱ ﮔﺮﻭﻩ ﺑﻨﺪﻱ ﻭ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩﻥ ﻣﺎﺷﻴﻦ ﻣﺮﺑﻮﻃﻪ‬ ‫ﺑﺮﺍﺳﺎﺱ ﻧﺎﻡ ‪ host‬ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ‪ DNS‬ﺩﺭ ﺟﻬﺖ‬ ‫ﺗﺎﻣﻴﻦ ﺧﻮﺍﺳﺘﻪ ﺍﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﺭﻭﺷﻲ ﺟﻬﺖ ﺫﺧﻴﺮﻩ ﻧﻤﻮﺩﻥ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ‪DNS‬‬ ‫ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪.‬ﺍﻃﻼﻋﺎﺕ ﻭﺍﻗﻌﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺩﺍﻣﻨﻪ ﻫﺎ ﺩﺭ ﻓﺎﻳﻠﻲ ﺑﺎ ﻧﺎﻡ‬

‫‪Zone‬‬

‫‪ database‬ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﻓﺎﻳﻞ ﻫﺎ‪ ،‬ﻓﺎﻳﻞ ﻫﺎﻱ ﻓﻴﺰﻳﮑﻲ ﺑﻮﺩﻩ ﮐﻪ ﺑﺮ ﺭﻭﻱ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺫﺧﻴﺮﻩ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺁﺩﺭﺱ ﻣﺤﻞ ﻗﺮﺍﺭ ﮔﻴﺮﻱ ﻓﺎﻳﻞ ﻫﺎﻱ ﻓﻮﻕ‬ ‫‪ systemroot%\system32\dns%‬ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﻫﺪﻑ ﺑﺮﺭﺳﻲ‬ ‫‪ Zone‬ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺑﻮﺩﻩ ﮐﻪ ﺑﻪ ﺩﻭ ﻧﻮﻉ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬ ‫•‬

‫‪Forward Lookup Zone‬‬

‫•‬

‫‪Reverse Lookup Zone‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺗﺸﺮﻳﺢ ﻋﻤﻠﮑﺮﺩ ﻫﺮ ﻳﮏ ﺍﺯ ‪ Zone‬ﻫﺎﻱ ﻓﻮﻕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

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‫‪Forward Lookup Zone‬‬ ‫ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ‪ Zone‬ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻣﮑﺎﻧﻴﺰﻣﻲ ﺑﺮﺍﻱ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ‪ host‬ﺑﻪ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ Zone .‬ﻫﺎ ﺩﺍﺭﺍﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻫﺴﺘﻨﺪ ﮐﻪ‬ ‫ﺑﺼﻮﺭﺕ ﺭﮐﻮﺭﺩﻫﺎﻱ ﺧﺎﺹ ﺩﺭ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺮﺑﻮﻃﻪ ﺫﺧﻴﺮﻩ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﺭﮐﻮﺭﺩﻫﺎ ﺭﺍ " ﺭﮐﻮﺭﺩﻫﺎﻱ ﻣﻨﺒﻊ ‪ " Record Resource‬ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﺭﮐﻮﺭﺩﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﻨﺎﺑﻊ ﻗﺎﺑﻞ ﺩﺳﺘﺮﺱ ﺩﺭ ﻫﺮ ‪ Zone‬ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﻨﺪ‬ ‫ﮐﺮﺩ‪.‬‬ ‫ﺗﻔﺎﻭﺕ ﺑﻴﻦ ‪ Domain‬ﻭ ‪Zone‬‬

‫ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺍﻳﻦ ﻧﮑﺘﻪ ﺍﺷﺎﺭﻩ ﻧﻤﻮﺩ ﮐﻪ ‪ Zone‬ﻫﺎ ﺑﺎ ﺩﺍﻣﻨﻪ ﻫﺎ )‪(Domain‬‬

‫ﻳﮑﺴﺎﻥ ﻧﺒﻮﺩﻩ ﻭ ﻳﮏ ‪ Zone‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺷﺎﻣﻞ ﺭﮐﻮﺭﺩﻫﺎﺋﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﭼﻨﺪﻳﻦ ﺩﺍﻣﻨﻪ ﺑﺎﺷﺪ‪.‬‬ ‫ﻣﺜﻼ" ﻓﺮﺽ ﮐﻨﻴﺪ ‪ ،‬ﺩﺍﻣﻨﻪ ‪ www.microsoft.com‬ﺩﺍﺭﺍﻱ ﺩﻭ ﺯﻳﺮ ﺩﺍﻣﻨﻪ ﺑﺎ ﻧﺎﻡ ‪East‬‬ ‫‪ , West‬ﺑﺎﺷﺪ‪.(West.microsoft.com , East.microsoft.com) .‬‬

‫ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺩﺍﺭﺍﻱ ﺩﺍﻣﻨﻪ ﺍﺧﺘﺼﺎﺻﻲ ‪ msn.com‬ﺑﻮﺩﻩ ﮐﻪ ﺧﻮﺩ ﺷﺎﻣﻞ ﺩﺍﺭﺍﻱ ﻳﮏ‬ ‫ﺯﻳﺮﺩﺍﻣﻨﻪ ﺑﺎ ﻧﺎﻡ ‪ mail.microsoft.com‬ﺍﺳﺖ‬

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‫ﺩﺍﻣﻨﻪ ﻫﺎﻱ ﻫﻤﺠﻮﺍﺭ ﻭ ﻏﻴﺮ ﻫﻤﺠﻮﺍﺭ ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺍﻣﻨﻪ ﻫﺎﻱ‬

‫ﻫﻤﺠﻮﺍﺭ ﻫﻤﺪﻳﮕﺮ ﺭﺍ ﺣﺲ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ) ﺑﺮﺍﻱ ﻳﮑﺪﻳﮕﺮ ﻣﻠﻤﻮﺱ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ(‪.‬‬

‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺜﺎﻝ ﻓﻮﻕ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪ Zone Microsoft.com‬ﻫﻤﺠﻮﺍﺭ ﻭ ﺩﺍﻣﻨﻪ‬ ‫ﻫﺎﻱ ‪ Msn.com‬ﻭ ‪ Microsoft.com‬ﻏﻴﺮ ﻫﻤﺠﻮﺍﺭ ﻫﺴﺘﻨﺪ‪.‬‬

‫‪ Zone‬ﻫﺎ ﻣﺠﻮﺯ ﻭﺍﮔﺬﺍﺭﻱ ﻣﺴﺌﻮﻟﻴﺖ ﺑﺮﺍﻱ ﭘﺸﺘﻴﺒﺎﻧﻲ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺩﺭ ‪ Zone‬ﺭﺍ ﻓﺮﺍﻫﻢ‬

‫ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ Zone .‬ﻫﺎ ﺭﻭﺷﻲ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﻭﺍﮔﺬﺍﺭﻱ ﻣﺴﺌﻮﻟﻴﺖ ﭘﺸﺘﻴﺒﺎﻧﻲ ﻭ ﻧﮕﻬﺪﺍﺭﻱ‬ ‫ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺮﺑﻮﻃﻪ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﺷﺮﮐﺘﻲ ﺑﺎ ﻧﺎﻡ ‪TACteam‬‬ ‫ﻭﺟﻮﺩﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﺷﺮﮐﺖ ﻓﻮﻕ ﺍﺯ ﺩﺍﻣﻨﻪ ﺍﻱ ﺑﺎ ﻧﺎﻡ ‪ tacteam.net‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺷﺮﮐﺖ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﺷﻌﺒﺎﺗﻲ ﺩﺭ ‪ and Boston ,San Francisco, Dallas‬ﺍﺳﺖ‪.‬‬ ‫ﺷﻌﺒﻪ ﺍﺻﻠﻲ ﺩﺭ ‪ Dallas‬ﺑﻮﺩﻩ ﮐﻪ ﻣﺪﻳﺮﺍﻥ ﻣﺘﻌﺪﺩﻱ ﺑﺮﺍﻱ ﻣﺪﻳﺮﻳﺖ ﺷﺒﮑﻪ ﺩﺭ ﺁﻥ ﻓﻌﺎﻟﻴﺖ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺷﻌﺒﻪ ‪ San Francisco‬ﻧﻴﺰ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﻣﺪﻳﺮ ﻭﺭﺯﻳﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﻈﺎﺭﺕ ﺑﺮ‬ ‫ﺳﺎﻳﺖ ﺍﺳﺖ ‪ .‬ﺷﻌﺒﻪ ‪ Boston‬ﺩﺍﺭﺍﻱ ﻣﺪﻳﺮﻳﺘﻲ ﮐﺎﺭﺁﻣﺪ ﺑﺮﺍﻱ ﻣﺪﻳﺮﻳﺖ ‪ DNS‬ﻧﻤﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺑﻨﺎﺑﺮﺍﻳﻦ ﻫﻤﻮﺍﺭﻩ ﻧﮕﺮﺍﻧﻲ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﻭﺍﮔﺬﺍﺭﻱ ﻣﺴﺌﻮﻟﻴﺖ ﻧﮕﻬﺪﺍﺭﻱ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ‬ ‫ﻳﮏ ﻓﺮﺩ ﺩﺭ ‪ Boston‬ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪ .‬ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺖ ‪ Dallas‬ﺩﺭ ﺣﻮﺯﻩ‬ ‫‪ tacteam.net‬ﺑﻮﺩﻩ ﻭ ﻣﻨــــــﺎﺑﻊ ﻣﻮﺟـــﻮﺩ ﺩﺭ ‪ San Francisco‬ﺩﺭ ﺳﺎﻳـــﺖ‬ ‫‪ west.tacteam.net‬ﻭ ﻣﻨــــــﺎﺑﻊ ﻣﻮﺟـــــﻮﺩ ﺩﺭ ‪ Boston‬ﺩﺭ ﺳﺎﻳـــﺖ‬ ‫‪ east.tacteam.net‬ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﻣﺎ ﺻﺮﻓﺎ" ﺩﻭ ‪ Zone‬ﺭﺍ‬ ‫ﺑﺮﺍﻱ ﻣﺪﻳﺮﻳﺖ ﺳﻪ ﺩﺍﻣﻨﻪ ﺍﻳﺠﺎﺩ ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ‪ .‬ﻳﮏ ‪ Zone‬ﺑﺮﺍﻱ ‪ tacteam.net‬ﮐﻪ‬

‫ﻣﺴﺌﻮﻟﻴﺖ ﻣﻨﺎﺑﻊ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ tacteam.net‬ﻭ ‪ east.tacteam.net‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ‬

‫ﻭ ﻳﮏ ‪ Zone‬ﺩﻳﮕﺮ ﺑﺮﺍﻱ ‪ west.tacteam.net‬ﮐﻪ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺖ‬ ‫‪ San Francisco‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ ‪ .‬ﺍﺳﺎﻣﻲ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﻫﺮ ‪ Zone‬ﺑﻪ ﭼﻪ‬

‫ﺻﻮﺭﺕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻧﺘﺨﺎﺏ ﮔﺮﺩﻧﻨﺪ؟ ﻫﺮ ‪ Zone‬ﻧﺎﻡ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺭﻳﺸﻪ ﻭ ﻳﺎ ﺑﺎﻻﺗﺮﻳﻦ‬ ‫ﺳﻄﺢ ﺩﺍﻣﻨﻪ ﺍﻗﺘﺒﺎﺱ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺑﺮﺍﻱ ﻳﮏ ﻣﻨﺒﻊ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺩﺍﻣﻨﻪ‬ ‫‪ west.tacteam.net‬ﺑﺮﺍﻱ ‪ DNS‬ﻭﺍﺻﻞ ﮔﺮﺩﺩ ) ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ‬ ‫‪216‬‬

‫‪ ( tacteam.net‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ tacteam.net‬ﺻﺮﻓﺎ" ﺷﺎﻣﻞ ﻳﮏ ‪ Zone‬ﻧﺨﻮﺍﻫﺪ‬

‫ﺑﻮﺩ‪.‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﻨﻲ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻳﮏ ‪ ) Delegation‬ﻭﺍﮔﺬﺍﺭﻱ‬

‫ﻣﺴﺌﻮﻟﻴﺖ ( ﺑﻮﺩﻩ ﮐﻪ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ west.tacteam.net‬ﺍﺷﺎﺭﻩ‬ ‫ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺩﺭﺧﻮﺍﺳﺖ ﻣﺮﺑﻮﻃﻪ ﺑﺮﺍﻱ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﺑﻪ ﺁﺩﺭﺱ ﺑﺪﺭﺳﺘﻲ ﺑﻪ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﺮﺑﻮﻃﻪ ﻫﺪﺍﻳﺖ ﺗﺎ ﻣﺸﮑﻞ ﺑﺮﻃﺮﻑ ﮔﺮﺩﺩ‪.‬‬

‫‪Reverse Lookup Zones‬‬ ‫‪Zone‬ﻫﺎ ﻱ ﺍﺯ ﻧﻮﻉ ‪ Forward‬ﺍﻣﮑﺎﻥ ﺗﺮﺟﻤﻪ ﻧﺎﻡ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮏ ‪ IP‬ﺭﺍ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪..‬ﻳﮏ ‪ Reverse Lookup‬ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ ﺑﻪ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ﮐﻪ‬ ‫ﻋﻤﻠﻴﺎﺕ ﻣﺨﺎﻟﻒ ﻋﻤﻠﻴﺎﺕ ﮔﻔﺘﻪ ﺷﺪﻩ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪ :‬ﺗﺮﺟﻤﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺑﻪ ﻳﮏ ﻧﺎﻡ‪.‬‬ ‫ﻣﺜﻼ" ﻓﺮﺽ ﮐﻨﻴﺪ ﺷﻤﺎ ﻣﻲ ﺩﺍﻧﻴﺪ ﮐﻪ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ‪١٩٢,١٦٨,١,٣‬‬ ‫ﺍﺳﺖ ﺍﻣﺎ ﻋﻼﻗﻪ ﻣﻨﺪ ﻫﺴﺘﻴﻢ ﮐﻪ ﻧﺎﻡ ﺁﻥ ﺭﺍ ﻧﻴﺰ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﺎﺳﺨﮕﻮﺋﻲ ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎ ﺳﻴﺴﺘﻢ ‪ DNS‬ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ‪ Zone‬ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ Zone .‬ﻫﺎﻱ ﻓﻮﻕ‬

‫ﺑﺴﺎﺩﮔﻲ ﻭ ﺭﺍﺣﺘﻲ ‪ Forward Zone‬ﻫﺎ ﺭﻓﺘﺎﺭ ﻧﻤﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﺜﻼ" ﻓﺮﺽ ﮐﻨﻴﺪ‬ ‫‪ Forward Lookup Zone‬ﻣﺸﺎﺑﻪ ﻳﮏ ﺩﻓﺘﺮﭼﻪ ﺗﻠﻔﻦ ﺑﺎﺷﺪ ﺍﻳﻨﺪﮐﺲ ﺍﻳﻦ ﻧﻮﻉ ﺩﻓﺘﺮﭼﻪ‬

‫ﻫﺎ ﺑﺮ ﺍﺳﺎﺱ ﻧﺎﻡ ﺍﺷﺨﺎﺹ ﺍﺳﺖ ‪.‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﻳﺎﻓﺘﻦ ﻳﮏ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ﺑﺎ ﺣﺮﮐﺖ ﺑﺮ ﺭﻭﻱ ﺣﺮﻑ‬

‫ﻣﺮﺑﻮﻃﻪ ﻭ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩﻥ ﻟﻴﺴﺖ ﮐﻪ ﺑﺘﺮﺗﻴﺐ ﺣﺮﻭﻑ ﺍﻟﻔﺒﺎﺀ ﺍﺳﺖ ﻗﺎﺩﺭ ﺑﻪ ﻳﺎﻓﺘﻦ ﻧﺎﻡ ﺷﺨﺺ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺍﻫﻴﺪ ﺑﻮﺩ‪ .‬ﺍﮔﺮ ﻣﺎ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﻓﺮﺩﻱ ﺭﺍ ﺑﺪﺍﻧﻴﻢ ﻭ ﻗﺼﺪ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ﺍﺯ ﻧﺎﻡ ﻭﻱ‬ ‫ﻧﻴﺰ ﺁﮔﺎﻫﻲ ﭘﻴﺪﺍ ﻧﻤﺎﺋﻴﻢ ﭼﻪ ﻧﻮﻉ ﻓﺮﺁﻳﻨﺪﻱ ﺭﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩ؟‪ .‬ﺍﺯ ﺁﻧﺠﺎﺋﻴﮑﻪ ﺩﻓﺘﺮﭼﻪ‬ ‫ﺗﻠﻔﻦ ﺑﺮ ﺍﺳﺎﺱ ﻧﺎﻡ ﺍﻳﻨﺪﮐﺲ ﺷﺪﻩ ﺍﺳﺖ ﺗﻨﻬﺎ ﺭﺍﻩ ﺣﺮﮐﺖ ﻭ ﺟﺴﺘﺠﻮ ﺩﺭ ﺗﻤﺎﻡ ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ ﻫﺎ‬ ‫ﻭ ﻳﺎﻓﺘﻦ ﻧﺎﻡ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ ‪.‬ﻗﻄﻌﺎ" ﺭﻭﺵ ﻓﻮﻕ ﺭﻭﺵ ﻣﻨﺎﺳﺒﻲ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻞ‬ ‫ﻣﺸﮑﻞ ﻓﻮﻕ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻳﺎﻓﺘﻦ ﻧﺎﻡ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ‪ IP‬ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ﺍﺯ ﻳﮏ ﺩﺍﻣﻨﻪ ﺟﺪﻳﺪ ﺑﺎ‬

‫ﻧﺎﻡ ‪ in-addr.arpa‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺍﻣﻨﻪ ﻓﻮﻕ ﺍﺳﺎﻣﻲ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﺩﺍﻣﻨﻪ ﻫﺎ ﺭﺍ ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﺷﻨﺎﺳﻪ ﺷﺒﮑﻪ )‪ (Network ID‬ﺍﻳﻨﺪﮐﺲ ﻭ ﺑﺎﻋﺚ ﺍﻓﺰﺍﻳﺶ ﺳﺮﻋﺖ ﻭ ﮐﺎﺭﺁﺋﻲ ﺩﺭ ﺑﺎﺯﻳﺎﺑﻲ‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺩﺭﺧﻮﺍﺳﺖ ﻫﺎ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻣﺪﻳﺮﻳﺘﻲ ‪ DNS‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺮﺍﺣﺘﻲ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﻳﺠﺎﺩ ﺍﻳﻦ ﻧﻮﻉ ‪ Zone‬ﻫﺎ‬ ‫ﻧﻤﻮﺩ‪ .‬ﻣﺜﻼ" ﺍﮔﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ‪ ١٩٢,١٦٨,١,٠‬ﺑﺎﺷﺪ ﻳﮏ ﺁﺩﺭﺱ ﻣﻌﮑﻮﺱ ﺍﻳﺠﺎﺩ ﻭ‬ ‫‪ Zone‬ﻣﺮﺑﻮﻃﻪ ﺑﺼﻮﺭﺕ ﺯﻳﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ‪:‬‬ ‫‪1.168.192.in‬‬‫‪addr.arpa.dns‬‬

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‫ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ‪DNS‬‬ ‫‪ DNS‬ﺍﺯﮐﻠﻤﺎﺕ ‪ Domain Name System‬ﺍﻗﺘﺒﺎﺱ ﻭ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺷﻨﺎﺧﺘﻪ‬

‫ﺷﺪﻩ ﺩﺭ ﻋﺮﺻﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺧﺼﻮﺻﺎ" ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﻭ ‪ Domain‬ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺯﻣﺎﻧﻲ ﮐﻪ ﺷﻤﺎ ﺁﺩﺭﺱ ‪ www.irib.ir‬ﺭﺍ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ ﺗﺎﻳﭗ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻧﺎﻡ ﻓﻮﻕ ﺑﻪ‬

‫ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻭ ﺑﺮ ﺍﺳﺎﺱ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ﺧﺎﺹ ) ‪ ( query‬ﮐﻪ ﺍﺯ ﺟﺎﻧﺐ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ‬

‫ﺻﺎﺩﺭ ﻣﻲ ﺷﻮﺩ‪ ،‬ﺗﺮﺟﻤﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺗﺎﺭﻳﺨﭽﻪ ‪DNS‬‬ ‫‪ ، DNS‬ﺯﻣﺎﻧﻲ ﮐﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺗﺎ ﺑﻪ ﺍﻳﻦ ﺍﻧﺪﺍﺯﻩ ﮔﺴﺘﺮﺵ ﭘﻴﺪﺍ ﻧﮑﺮﺩﻩ ﺑﻮﺩ ﻭ ﺻﺮﻓﺎ" ﺩﺭ ﺣﺪ‬ ‫ﻭ ﺍﻧﺪﺍﺯﻩ ﻳﮏ ﺷﺒﮑﻪ ﮐﻮﭼﮏ ﺑﻮﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺁﻥ ﺯﻣﺎﻥ‪ ،‬ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬

‫ﻣﻴﺰﺑﺎﻥ ﺑﻪ ﺻﻮﺭﺕ ﺩﺳﺘﻲ ﺩﺭ ﻓﺎﻳﻠﻲ ﺑﺎ ﻧﺎﻡ ‪ HOSTS‬ﺩﺭﺝ ﻣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﻓﺎﻳﻞ ﻓﻮﻕ ﺑﺮ ﺭﻭﻱ‬ ‫ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﺮﮐﺰﻱ ﻗﺮﺍﺭ ﻣﻲ ﮔﺮﻓﺖ‪ .‬ﻫﺮ ﺳﺎﻳﺖ ﻭ ﻳﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﻪ ﻧﻴﺎﺯﻣﻨﺪ ﺗﺮﺟﻤﻪ‬ ‫ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ ﺑﻮﺩ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻓﺎﻳﻞ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﻮﺩ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ‬ ‫ﮔﺴﺘﺮﺵ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻴﺰﺑﺎﻥ‪ ،‬ﺣﺠﻢ ﻓﺎﻳﻞ ﻓﻮﻕ ﻧﻴﺰ ﺍﻓﺰﺍﻳﺶ ﻭ‬

‫ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﮔﺮﺩﻳﺪ ) ﺍﻓﺰﺍﻳﺶ ﺗﺮﺍﻓﻴﮏ ﺷﺒﮑﻪ (‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺴﺎﺋﻞ‬ ‫ﻓﻮﻕ‪ ،‬ﺩﺭ ﺳﺎﻝ ‪ ۱۹۸۴‬ﺗﮑﻨﻮﻟﻮﮊﻱ ‪ DNS‬ﻣﻌﺮﻓﻲ ﮔﺮﺩﻳﺪ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪DNS‬‬

‫‪ ، DNS‬ﻳﮏ "ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺯﻳﻊ ﺷﺪﻩ " ﺍﺳﺖ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﻣﺴﺘﻘﺮ‬ ‫ﻣﻲ ﺷﻮﺩ ) ﻣﺸﺎﺑﻪ ﺭﻳﺸﻪ ﻫﺎﻱ ﻳﮏ ﺩﺭﺧﺖ ﮐﻪ ﺍﺯ ﺭﻳﺸﻪ ﺍﺻﻠﻲ ﺍﻧﺸﻌﺎﺏ ﻣﻲ ﺷﻮﻧﺪ (‪ .‬ﺍﻣﺮﻭﺯﻩ‬ ‫ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺩﺍﺭﺍﻱ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﮐﻮﭼﮏ ﺩﺭ ﺳﺎﺯﻣﺎﻥ ﺧﻮﺩ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ﺗﺎ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺍﻳﺠﺎﺩ ﮔﺮﺩﺩ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﺪﻭﻥ ﺑﺮﻭﺯ ﻫﻴﭽﮕﻮﻧﻪ ﻣﺸﮑﻠﻲ‪ ،‬ﻳﮑﺪﻳﮕﺮ‬ ‫ﺭﺍ ﭘﻴﺪﺍ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﻭﻳﻨﺪﻭﺯ ‪ ۲۰۰۰‬ﻭ ﺍﮐﺘﻴﻮ ﺩﺍﻳﺮﮐﺘﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪،‬‬

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‫ﻗﻄﻌﺎ" ﺍﺯ ‪ DNS‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ ، IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺷﺮﮐﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﻧﺴﺨﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺧﻮﺩ ﺭﺍ ﺑﺎ ﻧﺎﻡ‬

‫‪ Windows Internet Name Service ) WINS‬ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻧﻤﻮﺩ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ ﻣﺒﺘﻨﻲ ﺑﺮ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻗﺪﻳﻤﻲ ﺑﻮﺩ ﻭ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ‬

‫ﮔﺮﺩﻳﺪ ﮐﻪ ﻫﺮﮔﺰ ﺩﺍﺭﺍﻱ ﮐﺎﺭﺍﺋﻲ ﻣﺸﺎﺑﻪ ‪ DNS‬ﻧﺒﻮﺩﻧﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻃﺒﻴﻌﻲ ﺑﻮﺩ ﮐﻪ ﺷﺮﮐﺖ‬ ‫ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺍﺯ ‪ WINS‬ﻓﺎﺻﻠﻪ ﮔﺮﻓﺘﻪ ﻭ ﺑﻪ ﺳﻤﺖ ‪ DNS‬ﺣﺮﮐﺖ ﮐﻨﺪ‪.‬‬ ‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪ DNS‬ﺑﺮﺍﻱ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻧﺎﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ Domain‬ﻣﻲ ﻧﻤﺎﻳﺪ‪،‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ ‪.‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﺧﻮﺩ ﺁﺩﺭﺱ ‪www. Cisco.com‬‬ ‫ﺭﺍ ﺗﺎﻳﭗ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ﻣﺒﺘﻨﻲ ﺑﺮ ‪ DNS‬ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﻭ ﺑﻪ ﻣﻘﺼﺪ ﻳﮏ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺻﺎﺩﺭ ﻣﻲ ﺷﻮﺩ‪ .‬ﻣﺎﻣﻮﺭﻳﺖ ﺩﺭﺧﻮﺍﺳﺖ ﺍﺭﺳﺎﻟﻲ‪ ،‬ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﻭﺏ ﺳﺎﻳﺖ ‪ Cisco‬ﺍﺳﺖ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﻭ ﻣﺪﻝ ﻣﺮﺟﻊ ‪OSI‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﻣﻌﻤﻮﻻ" ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ UDP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻤﻞ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ UDP‬ﻧﺴﺒﺖ ﺑﻪ ‪ TCP‬ﺩﺍﺭﺍﻱ ‪ overhead‬ﮐﻤﺘﺮﻱ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﻫﺮ ﺍﻧﺪﺍﺯﻩ‬ ‫‪ overhead‬ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﮐﻤﺘﺮ ﺑﺎﺷﺪ‪ ،‬ﺳﺮﻋﺖ ﺁﻥ ﺑﻴﺸﺘﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﮐﻪ‬ ‫ﺣﻤﻞ ﺩﺍﺩﻩ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ UDP‬ﺑﺎ ﻣﺸﮑﻞ ﻭ ﻳﺎ ﺑﻬﺘﺮ ﺑﮕﻮﺋﻴﻢ ﺧﻄﺎﺀ ﻣﻮﺍﺟﻪ ﮔﺮﺩﺩ‪،‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ TCP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻤﻞ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩﻩ ﺗﺎ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺍﻳﺠﺎﺩ‬ ‫ﮔﺮﺩﺩ ﮐﻪ ﺩﺍﺩﻩ ﺑﺪﺭﺳﺘﻲ ﻭ ﺑﺪﻭﻥ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﺑﻪ ﻣﻘﺼﺪ ﺧﻮﺍﻫﺪ ﺭﺳﻴﺪ‪.‬‬

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‫ﻓﺮﺁﻳﻨﺪ ﺍﺭﺳﺎﻝ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ DNS‬ﻭ ﺩﺭﻳﺎﻓﺖ ﭘﺎﺳﺦ ﺁﻥ ‪ ،‬ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﻧﻮﻉ ﺳﻴﺴﺘﻢ‬

‫ﻋﺎﻣﻞ ﻧﺼﺐ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺖ ‪.‬ﺑﺮﺧﻲ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ ﺍﺟﺎﺯﻩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ TCP‬ﺑﺮﺍﻱ ‪ DNS‬ﺭﺍ ﻧﺪﺍﺩﻩ ﻭ ﺻﺮﻓﺎ" ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ UDP‬ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺣﻤﻞ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺷﻮﺩ ‪ .‬ﺑﺪﻳﻬﻲ ﺍﺳﺖ ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻫﻤﻮﺍﺭﻩ ﺍﻳﻦ ﺍﺣﺘﻤﺎﻝ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ‬ ‫ﺩﺍﺷﺖ ﮐﻪ ﺑﺎ ﺧﻄﺎﻫﺎﺋﻲ ﻣﻮﺍﺟﻪ ﺷﺪﻩ ﻭ ﻋﻤﻼ" ﺍﻣﮑﺎﻥ ﺗﺮﺟﻤﻪ ﻧﺎﻡ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ‬

‫‪ Domain‬ﺑﻪ ﺁﺩﺭﺱ ‪ IP‬ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﺪ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﺍﺯ ﭘﻮﺭﺕ ‪ ۵۳‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻳﮏ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺑﻪ ﭘﻮﺭﺕ ‪ ۵۳‬ﮔﻮﺵ ﺩﺍﺩﻩ ﻭ ﺍﻳﻦ ﺍﻧﺘﻈﺎﺭ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ﮐﻪ ﻫﺮ‬ ‫ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﻱ ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ﻓﻮﻕ ﺭﺍ ﺩﺍﺭﺩ ﺍﺯ ﭘﻮﺭﺕ ﻣﺸﺎﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﻣﻤﮑﻦ ﺍﺳﺖ ﻣﺠﺒﻮﺭ ﺷﻮﻳﻢ ﺍﺯ ﭘﻮﺭﺕ ﺩﻳﮕﺮﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﺋﻴﻢ‪.‬‬ ‫ﻭﺿﻌﻴﺖ ﻓﻮﻕ ﺑﻪ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻧﺼﺐ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﺑﺴﺘﮕﻲ ﺩﺍﺭﺩ‪.‬‬

‫ﺳﺎﺧﺘﺎﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻧﺎﻡ ﺩﺍﻣﻨﻪ ﻫﺎ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ‬ ‫ﺍﻣﺮﻭﺯﻩ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﺳﺎﻳﺖ ﺑﺎ ﺍﺳﺎﻣﻲ ‪ Domain‬ﺛﺒﺖ ﺷﺪﻩ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬

‫ﺷﺎﻳﺪ ﺍﻳﻦ ﺳﻮﺍﻝ ﺑﺮﺍﻱ ﺷﻤﺎ ﺗﺎﮐﻨﻮﻥ ﻣﻄﺮﺡ ﺷﺪﻩ ﺑﺎﺷﺪ ﮐﻪ ﺍﻳﻦ ﺍﺳﺎﻣﻲ ﭼﮕﻮﻧﻪ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ‬ ‫ﻣﻲ ﺷﻮﻧﺪ؟ ﺳﺎﺧﺘﺎﺭ ‪ DNS‬ﺑﮕﻮﻧﻪ ﺍﻱ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪DNS‬‬ ‫ﺿﺮﻭﺭﺗﻲ ﺑﻪ ﺁﮔﺎﻫﻲ ﺍﺯ ﺗﻤﺎﻣﻲ ﺍﺳﺎﻣﻲ ‪ Domain‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﻧﺪﺍﺷﺘﻪ ﻭ ﺻﺮﻓﺎ" ﻣﻴﺰﺍﻥ ﺁﮔﺎﻫﻲ‬

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‫ﻭﻱ ﺑﻪ ﻳﮏ ﺳﻄﺢ ﺑﺎﻻﺗﺮ ﻭ ﻳﮏ ﺳﻄﺢ ﭘﺎﺋﻴﻦ ﺗﺮ ﺍﺯ ﺧﻮﺩ ﻣﺤﺪﻭﺩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﺑﺨﺶ‬

‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ‪ DNS‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫‪ ، internic‬ﻣﺴﺌﻮﻟﻴﺖ ﮐﻨﺘﺮﻝ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ﺭﻳﺸﻪ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﮐﻪ ﺷﺎﻣﻞ ﺗﻤﺎﻣﻲ‬

‫‪ Domain‬ﻫﺎﻱ ﺳﻄﺢ ﺑﺎﻻ ﻣﻲ ﺑﺎﺷﺪ ) ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﺑﻪ ﺭﻧﮓ ﺁﺑﻲ ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﺷﺪﻩ ﺍﺳﺖ(‪.‬‬ ‫ﺩﺭ ﺑﺨﺶ ﻓﻮﻕ ﺗﻤﺎﻣﻲ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺭﻳﺸﻪ ﻗﺮﺍﺭ ﺩﺍﺷﺘﻪ ﻭ ﺁﻧﺎﻥ ﺩﺍﺭﺍﻱ ﺁﮔﺎﻫﻲ‬ ‫ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﻄﺢ ﭘﺎﺋﻴﻦ ﺗﺮ ﺍﺯ ﺧﻮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ )ﻣﺜﻼ"‬

‫‪ .(microsoft.com‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﺭﻳﺸﻪ ﻣﺸﺨﺺ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ﮐﻪ ﮐﺪﺍﻡ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ‪ microsoft.com‬ﻭ ﻳﺎ ‪Cisco.com‬‬ ‫ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﻫﺮ ‪ domain‬ﺷﺎﻣﻞ ﻳﮏ ‪ Primary DNS‬ﻭ ﻳﮏ ‪ Secondary DNS‬ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫‪ ، Primary DNS‬ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺗﺒﻂ ﺑﺎ ‪ Domain‬ﺧﻮﺩ ﺭﺍ ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪ Secondary DNS‬ﺑﻪ ﻣﻨﺰﻟﻪ ﻳﮏ ‪ backup‬ﺑﻮﺩﻩ ﻭ ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﮐﻪ ‪Primary DNS‬‬

‫ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﻣﻲ ﺷﻮﺩ ﺍﺯ ﺁﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻪ ﻓﺮﺁﻳﻨﺪﻱ ﮐﻪ ﺑﺮ ﺍﺳﺎﺱ ﺁﻥ ﻳﮏ‬

‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ Primary DNS‬ﺍﻃﻼﻋﺎﺕ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪Secondary‬‬ ‫‪ DNS‬ﺗﮑﺜﻴﺮ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ Zone Transfer ،‬ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺍﻣﺮﻭﺯﻩ ﺻﺪﻫﺎ ﻭﺏ ﺳﺎﻳﺖ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﻳﮏ ‪ Domain‬ﺭﺍ‬ ‫ﺛﺒﺖ ﻭ ﻳﺎ ﺍﺻﻄﻼﺣﺎ" ﺭﻳﺠﺴﺘﺮ ﻧﻤﻮﺩ ‪ .‬ﭘﺲ ﺍﺯ ﺛﺒﺖ ﻳﮏ ‪ ، Domain‬ﺍﻣﮑﺎﻥ ﻣﺪﻳﺮﻳﺖ ﺁﻥ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ﺷﻤﺎ ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﻭ ﻣﻲ ﺗﻮﺍﻥ ﺭﮐﻮﺭﺩﻫﺎﻱ ﻣﻨﺒﻊ )‪ ( RR‬ﺭﺍ ﺩﺭ ﺁﻥ ﺗﻌﺮﻳﻒ ﻧﻤﻮﺩ‪.‬‬

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‫‪ Support, www‬ﻭ ‪ ، Routers‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺭﮐﻮﺭﺩﻫﺎﻱ ﻣﻨﺒﻊ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺩﺍﻣﻨﻪ‬

‫‪ Cisco.com‬ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ‪ Subdomain‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﮏ ﺑﺮﻧﺎﻣﻪ‬ ‫ﻣﺪﻳﺮﻳﺘﻲ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ www .‬ﻭ ﻳﺎ ﻫﺮ ﻧﻮﻉ ﺭﮐﻮﺭﺩ ﻣﻨﺒﻊ ﺩﻳﮕﺮﻱ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻓﻮﻕ ﺗﻌﺮﻳﻒ ﻧﻤﻮﺩ ‪ .‬ﭘﺲ ﺍﺯ ﺍﻋﻤﺎﻝ ﺗﻐﻴﻴﺮﺍﺕ ﺩﻟﺨﻮﺍﻩ ﺧﻮﺩ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬

‫‪ ، Domain‬ﻣﺤﺘﻮﻳﺎﺕ ﻓﺎﻳﻞ ﻫﺎﻱ ﺧﺎﺻﻲ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺍﻧﺪ ﻧﻴﺰ‬

‫ﺗﻐﻴﻴﺮ ﻧﻤﻮﺩﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺗﻐﻴﻴﺮﺍﺕ ﻓﻮﻕ ﺑﻪ ﺳﺎﻳﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﺗﺎﺋﻴﺪ ﺷﺪﻩ ﺍﻃﻼﻉ ﺩﺍﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻓﻮﻕ‪ ،‬ﻣﺴﺌﻮﻟﻴﺖ ‪ Domain‬ﺷﻤﺎ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ‬

‫ﺗﻤﺎﻣﻲ ﺍﻳﻨﺘﺮﻧﺖ ﮐﻪ ﺑﻪ ﺍﻳﻦ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ‪ DNS‬ﻣﺘﺼﻞ ﻣﻲ ﺷﻮﻧﺪ ﺍﺯ ﺗﻐﻴﻴﺮﺍﺕ ﺍﻳﺠﺎﺩ‬ ‫ﺷﺪﻩ ﺁﮔﺎﻩ ﻭ ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺨﺶ ﻫﺎﻱ ‪ Domain‬ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ‪ Support.Cisco.com‬ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﺷﻤﺎ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﻣﺪﻳﺮﻳﺖ ﺩﺍﻣﻨﻪ ﻫﺎﻱ ‪ .Com‬ﺭﺍ ﺩﺍﺭﺩ‪ ،‬ﺍﺭﺗﺒﺎﻁ‬

‫ﺑﺮﻗﺮﺍﺭ ﻧﻤﻮﺩﻩ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ ﺍﻃﻼﻋﺎﺕ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺩﺍﻣﻨﻪ ‪ Cisco.com‬ﺭﺍ‬ ‫ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ‪ .‬ﺩﺭ ﻧﻬﺎﻳﺖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪Cisco.com‬‬ ‫) ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻓﻮﻕ‪ ،‬ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺗﺒﻂ ﺑﺎ ﺩﺍﻣﻨﻪ ‪ Cisco.com‬ﺭﺍ ﺩﺭ ﺧﻮﺩ‬

‫ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﻧﻤﺎﻳﺪ (‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Support.Cisco.com‬ﺭﺍ‬ ‫ﻣﺸﺨﺺ ﻧﻤﻮﺩﻩ ﺗﺎ ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺁﻥ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬ ‫ﻧﺤﻮﻩ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ‪ Domain‬ﺗﻮﺳﻂ ‪DNS‬‬ ‫ﺁﻳﺎ ﺗﺎﮐﻨﻮﻥ ﺍﻳﻦ ﺳﻮﺍﻝ ﺑﺮﺍﻱ ﺷﻤﺎ ﻣﻄﺮﺡ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﭘﺲ ﺍﺯ ﺗﺎﻳﭗ ﻧﺎﻡ ﻳﮏ ﺳﺎﻳﺖ ﺩﺭ‬

‫ﻣﺮﻭﺭﮔﺮ ﻭﺏ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﺁﻥ ﭼﮕﻮﻧﻪ ﭘﻴﺪﺍ ﻣﻲ ﺷﻮﺩ؟ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮏ ﺳﺎﻳﺖ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﻗﺒﻞ ﺍﺯ ﻫﺮ ﭼﻴﺰ ﺁﺩﺭﺱ ‪ IP‬ﺁﻥ ﻣﺸﺨﺺ ﮔﺮﺩﺩ ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺮﺟﻤﻪ ﺍﺳﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻣﻴﺰﺑﺎﻥ ﻭ ‪ Domain‬ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ DNS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫‪ Queries‬ﻭ ‪Resolution‬‬

‫ﻳﮏ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ DNS‬ﻭ ﺍﺧﺬ ﭘﺎﺳﺦ ﻻﺯﻡ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪:‬‬ ‫•‬

‫ﺩﺭ ﺭﻭﺵ ﺍﻭﻝ ‪ ،‬ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻧﺎﻡ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﻣﺎﺩﺍﻣﻴﮑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻣﺠﺎﺯ ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﭘﻴﺪﺍ ﻧﺸﻮﺩ‪،‬‬ ‫ﺍﺩﺍﻣﻪ ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ )ﺭﻭﺵ ‪.( non Recursive query‬‬

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‫ﺩﺭ ﺭﻭﺵ ﺩﻭﻡ ‪ ،‬ﻣﺎﻣﻮﺭﻳﺖ ﺗﺮﺟﻤﻪ ﻧﺎﻡ ﺑﻪ ﺁﺩﺭﺱ ﺑﻪ ‪ DNS‬ﻭﺍﮔﺬﺍﺭ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ‬

‫ﺭﻭﺵ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺭﺧﻮﺍﺳﺖ ﺧﻮﺩ ﺑﺮﺍﻱ ‪ DNS‬ﻧﻤﻮﺩﻩ ﻭ‬

‫‪ DNS‬ﭘﺲ ﺍﺯ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺗﻲ ﺧﺎﺹ ﻭ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ‪ IP‬ﺳﺎﻳﺖ ﺩﺭﺧﻮﺍﺳﺘﻲ‪ ،‬ﺁﻥ ﺭﺍ‬ ‫ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ )ﺭﻭﺵ ‪.( Recursive query‬‬ ‫ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﮐﺎﺭ ﺩﺭ ﺭﻭﺵ ﺩﻭﻡ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

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‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺑﻪ ﺑﺮﺭﺳﻲ ﻳﮏ ﻧﻤﻮﻧﻪ ﻣﺜﺎﻝ ﻣﻲ ﭘﺮﺩﺍﺯﻳﻢ‪.‬‬

‫ﺯﻣﺎﻧﻲ ﮐﻪ ﺷﻤﺎ ﻗﺼﺪ ﻣﺸﺎﻫﺪﻩ ﻳﮏ ﻭﺏ ﺳﺎﻳﺖ ﻧﻈﻴﺮﻭﺏ ﺳﺎﻳﺖ)‪ ( www.cisco.com‬ﺭﺍ‬

‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪،‬‬ ‫ﭘﺲ ﺍﺯ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ﻭ ﺗﺎﻳﭗ ﺁﺩﺭﺱ‬

‫‪ http://www.cisco.com‬ﻭ ﻳﺎ ‪ ، www.cisco.com‬ﭘﺲ ﺍﺯ ﻣﺪﺕ ﺯﻣﺎﻥ‬ ‫ﮐﻮﺗﺎﻫﻲ ! ﺻﻔﺤﻪ ﺍﺻﻠﻲ ﻭﺏ ﺳﺎﻳﺖ ﺩﺭ ﻣﺮﻭﺭﮔﺮ ﺷﻤﺎ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺮﺍﻱ ﻳﺎﻓﺘﻦ‬ ‫ﺁﺩﺭﺱ ‪ IP‬ﻭﺏ ﺳﺎﻳﺖ ﺩﺭﺧﻮﺍﺳﺘﻲ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺩﻧﺒﺎﻝ ﻣﻲ ﺷﻮﺩ ‪:‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻣﺮﻭﺭﮔﺮ ﻭ ﺩﺭﺝ ﺁﺩﺭﺱ ‪ www.cisco.com‬ﺩﺭ ﺑﺨﺶ‬

‫ﺁﺩﺭﺱ ﺁﻥ ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﻘﻄﻊ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺩﺍﺭﺍﻱ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﻭﺏ ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ ﻧﻤﻲ ﺑﺎﺷﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ DNS‬ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ‬

‫ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺍﻳﻨﺘﺮﻧﺖ ) ‪ ( ISP‬ﺍﺭﺳﺎﻝ ﻣﻲ‬

‫ﻧﻤﺎﻳﺪ‪ .‬ﺣﺘﻤﺎ" ﺍﻳﻦ ﺳﻮﺍﻝ ﺑﺮﺍﻱ ﺷﻤﺎ ﻣﻄﺮﺡ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺍﺯ‬ ‫ﺁﺩﺭﺱ ‪ IP‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺁﮔﺎﻫﻲ ﻣﻲ ﻳﺎﺑﺪ ﺗﺎ ﺩﺭﺧﻮﺍﺳﺖ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﻭﻱ‬

‫ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ ؟ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺷﻤﺎ ﺍﺯ ﻃﺮﻳﻖ ‪ up-Dial‬ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﻳﺪ‬

‫‪ ،‬ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻨﻈﻴﻤﺎﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ) ﺍﻳﺴﺘﺎ ﻭ ﭘﻮﻳﺎ ( ﭘﺮﻭﺗﮑﻞ ‪TCP/IP‬‬ ‫ﻣﺮﺗﺒﻂ ﺑﺎ ﺁﺩﺍﭘﺘﻮﺭ ﻣﺠﺎﺯﻱ ‪ up-Dial‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ‬ ‫ﺍﺗﺼﺎﻝ ﺩﺍﺋﻢ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺷﺒﮑﻪ ﻣﺤﻠﻲ ﻣﻲ ﺑﺎﺷﻴﺪ‪ ،‬ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺑﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯﺗﻨﻈﻴﻤﺎﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ )ﺍﻳﺴﺘﺎ ﻭ ﭘﻮﻳﺎ( ﭘﺮﻭﺗﮑﻞ‪ TCP/IP‬ﻣﺮﺗﺒﻂ ﺑﺎ ﺁﺩﺍﭘﺘﻮﺭ‬ ‫ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ) ‪ ( ISP‬ﺷﻤﺎ‪،‬‬

‫ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ ﺭﺍ ﻧﻤﻲ ﺩﺍﻧﺪ ﻭ ﺑﺪﻳﻦ ﺩﻟﻴﻞ‪ ،‬ﺁﺩﺭﺱ ﺳﺎﻳﺖ ﻓﻮﻕ ﺭﺍ ﺍﺯ‬ ‫ﻳﮑﻲ ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻧﺎﻡ ﺭﻳﺸﻪ ﺩﺭﺧﻮﺍﺳﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺭﻳﺸﻪ‪ ،‬ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺩ ﺭﺍ ﺑﺮﺭﺳﻲ ﻧﻤﻮﺩﻩ ﻭ‬ ‫ﺍﺯ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺍﻭﻟﻴﻪ ‪ Cisco.com‬ﺁﮔﺎﻫﻲ ﻣﻲ ﻳﺎﺑﺪ )‪: IP‬‬ ‫‪225‬‬

‫‪ . ( ١٩٨,١٣٣,٢١٩,٢٥‬ﭘﺲ ﺍﺯ ﺁﮔﺎﻫﻲ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ‬ ‫ﺑﻪ ‪ ، cisco.com‬ﭘﺎﺳﺦ ﻻﺯﻡ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ISP‬ﺷﻤﺎ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﮐﺰ ‪ ISP‬ﺷﻤﺎ ﺩﺍﻧﺶ ﻻﺯﻡ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺳﻴﺴﮑﻮ ﺭﺍ ﭘﻴﺪﺍ ﻧﻤﻮﺩﻩ ﻭ ﭘﺲ ﺍﺯ ﺑﺮﻗﺮﺍﺭﻱ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﻭﻱ ﺁﺩﺭﺱ ‪ IP‬ﻭﺏ ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ ) ‪ ( www.cisco.com‬ﺭﺍ ﺟﻮﻳﺎ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺷﻤﺎ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ Recursive‬ﺭﺍ ﺑﺮﺍﻱ‬ ‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Cisco.com‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ :‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﺳﻴﺴﮑﻮ‪ ،‬ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺩ ﺭﺍ ﺑﺮﺭﺳﻲ‬ ‫ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﻭﺟﻮﺩ ﺭﮐﻮﺭﺩ ‪ www.cisco.com‬ﺩﺭ ﺑﺎﻧﮏ ﺁﮔﺎﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﮐﻮﺭﺩ‬ ‫ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻣﻌﺎﺩﻝ ‪ IP:198.133.219.25‬ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ‬ ‫ﺧﺎﺹ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺑﺮ ﺭﻭﻱ ﻣﺎﺷﻴﻦ ﻣﺸﺎﺑﻬﻲ ﺍﺳﺖ ﮐﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫‪ DNS‬ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

‫‪ DNS‬ﺑﺮ ﺭﻭﻱ ﻳﮏ ﻣﺎﺷﻴﻦ ﻣﺸﺎﺑﻪ ﻧﺼﺐ ﻧﺸﺪﻩ ﺑﺎﺷﻨﺪ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﺁﻧﺎﻥ ﻣﺘﻔﺎﻭﺕ ﺑﻮﺩﻩ‬

‫ﻭ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺍﺯ ﻃﺮﻳﻖ ﺭﮐﻮﺭﺩﻫﺎﻱ ﻣﻨﺒﻊ ﻣﻮﺟﻮﺩ ﺩﺭ ﺑﺎﻧﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫‪ DNS‬ﻣﺸﺨﺺ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺷﺸﻢ ‪ :‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ DNS‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ ISP‬ﺷﻤﺎ ﺍﺯ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫‪ www.cisco.com‬ﺁﮔﺎﻫﻲ ﭘﻴﺪﺍ ﻧﻤﻮﺩﻩ ﻭ ﻧﺘـﺎﻳﺞ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴـﻮﺗﺮ ﺷــﻤﺎ ﺍﺭﺳﺎﻝ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﻫﻔﺘﻢ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺩﺭ ﺍﻳﻦ ﻣﻘﻄﻊ ﺩﺍﺭﺍﻱ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺁﺩﺭﺱ‬ ‫‪ IP‬ﻭﺏ ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ ﺑﻮﺩﻩ ﻭ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎ ﺁﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﺷﻤﺎ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ http‬ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﺳﻴﺴﮑﻮ ﺍﺭﺳﺎﻝ‬ ‫ﻧﻤﻮﺩﻩ ﻭ ﺍﺯ ﻭﻱ ﺩﺭﺧﻮﺍﺳﺖ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺍﺗﺮﻧﺖ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﺭﻭﺵ ﻫﺎﻱ ﻣﻄﻤﺌﻦ ﻭ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﻳﮑﻲ ﺍﺯ ﺭﻣﻮﺯ ﻣﻮﻓﻘﻴﺖ ﻫـﺮ‬

‫ﺳﺎﺯﻣﺎﻥ ﻭ ﻣﻮﺳﺴﻪ ﺍﺳﺖ‪ .‬ﻃﻲ ﺳﺎﻟﻴﺎﻥ ﺍﺧﻴﺮ ﻫﺰﺍﺭﺍﻥ ﭘﺮﻭﻧﺪﻩ ﻭ ﮐﺎﻏﺬ ﮐﻪ ﺣﺎﻭﻱ ﺍﻃﻼﻋــﺎﺕ ﺑﺎ‬

‫ﺍﺭﺯﺵ ﺑﺮﺍﻱ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﻮﺩﻩ ‪ ،‬ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺎ ﺗﻐﺬﻳﻪ ﺩﺭﻳﺎﺋﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﺍﻣﮑﺎﻥ ﻣﺪﻳﺮﻳﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺍﻃﻼﻋﺎﺕ ﻓﺮﺍﻫﻢ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﻣﺘﻔﺎﻭﺕ ﺩﺭ‬ ‫ﺍﻗﺼﻲ ﻧﻘﺎﻁ ﺟﻬﺎﻥ ﻗﺎﺩﺭﺑﻪ ﺍﺷﺘﺮﺍﮎ ﺍﻃﻼﻋﺎﺕ ﺑﻮﺩﻩ ﻭﺗﺼﻮﻳﺮﻱ ﺯﻳﺒﺎ ﺍﺯ ﻫﻤﻴﺎﺭﻱ ﻭﻫﻤﮑﺎﺭﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﻪ ﻧﻤﺎﻳﺶ ﻣﻲ ﮔﺬﺍﺭﻧﺪ‪.‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻭ ﺟﻬﺖ ﻧﻴﻞ ﺑﻪ ﺍﻫﺪﺍﻑ ﻓﻮﻕ ﻧﻘﺶ ﺑﺴﻴﺎﺭ ﻣﻬﻤﻲ ﺭﺍ ﺍﻳﻔﺎﺀ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬ﺍﻳﻨﺘﺮﻧﺖ ﮐﻪ ﻋﺎﻟﻲ ﺗﺮﻳﻦ ﺗﺒﻠﻮﺭ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ ﺍﺳﺖ‪،‬‬ ‫ﺍﻣﺮﻭﺯﻩ ﺩﺭ ﻣﻘﻴﺎﺱ ﺑﺴﻴﺎﺭ ﮔﺴﺘﺮﺩﻩ ﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﮔﺎﻥ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻭ ﻳﺎ‬

‫ﻓﺮﺁﻭﺭﺩﻩ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﻗﺎﻟﺐ ﻣﺤﺼﻮﻻﺕ ﺗﻮﻟﻴﺪﻱ ﻭ ﻳﺎ ﺧﺪﻣﺎﺕ ﺩﺭ ﺍﺧﺘــﻴـﺎﺭ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ﻗﺮﺍﺭﻣﻲ ﺩﻫﻨﺪ‪ .‬ﻭﺏ ﮐﻪ ﻋﺎﻟﻲ ﺗﺮﻳﻦ ﺳﺮﻭﻳﺲ ﺧﺪﻣﺎﺗﻲ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻲ ﺑﺎﺷﺪ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺭﺍ ﻗﺎﺩﺭ ﻣﻲ ﺳﺎﺯﺩ ﮐﻪ ﺩﺭ ﺍﻗﺼﻲ ﻧﻘﺎﻁ ﺩﻧﻴﺎ ﺍﻗﺪﺍﻡ ﺑﻪ ﺧﺮﻳﺪ‪ ،‬ﺁﻣﻮﺯﺵ‪ ،‬ﻣﻄﺎﻟﻌﻪ ﻭ ‪...‬‬

‫ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺷﺒﮑﻪ‪ ،‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ‬ ‫ﺍﺳﺖ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ ﻧﻤﻮﻧﻪ ﺍﻱ ﻋﻴﻨﻲ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺷﺒﮑﻪ ﻣﻴﻠﻴﻮﻥ ﻫﺎ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﺭ ﺍﻗﺼﻲ ﻧﻘﺎﻁ ﺟﻬﺎﻥ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﻧﺪ‪.‬ﺍﻳﻨﺘﺮﻧﺖ ﺷﺒﮑﻪ ﺍﻱ ﺍﺳﺖ ﻣﺸﺘﻤﻞ‬

‫ﺑﺮ ﺯﻧﺠﻴﺮﻩ ﺍﻱ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮﺍﺳﺖ ‪ .‬ﻧﻘﺶ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮏ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺗﺼﻮﻳﺮﻱ‬ ‫ﺑﺎ ﻧﺎﻡ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺴﻴﺎﺭ ﺣﺎﺋﺰ ﺍﻫﻤﻴﺖ ﺍﺳﺖ‪ .‬ﺗﺼﻮﻳﺮﻱ ﮐﻪ ﻫﺮ ﮐﺎﺭﺑﺮ ﺑﺎ ﻧﮕﺎﻩ ﮐﺮﺩﻥ ﺑﻪ ﺁﻥ ﮔﻤﺸﺪﻩ‬ ‫ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺁﻥ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺑﺨﺶ ﺑﻪ ﺑﺮﺭﺳﻲ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻭ ﺟﺎﻳﮕﺎﻩ‬

‫ﻣﻬﻢ ﺁﻧﺎﻥ ﺩﺭ ﺯﻣﻴﻨﻪ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺍﻃﻼﻋﺎﺕ ﻭ ﻣﺪﻳﺮﻳﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺍﻫﻴﻢ ﺩﺍﺷﺖ‪.‬‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﻭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮔﺴﺘﺮﺩﻩ‬

‫ﺗﺎﮐﻨﻮﻥ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺮ ﺍﺳﺎﺱ ﻣﻮﻟﻔﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬

‫ﻳﮑﻲ ﺍﺯ ﺍﻳﻦ ﻣﻮﻟﻔﻪ ﻫﺎ " ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ " ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﺑﺮ ﻫﻤﻴﻦ ﺍﺳﺎﺱ ﺷﺒﮑﻪ ﻫﺎ ﺑﻪ‬ ‫ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ‪ (Local area network(LAN‬ﻭ ‪Wide area (WAN‬‬

‫‪ (network‬ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭ ﻳﮏ ﺣﻮﺯﻩ ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﻣﺤﺪﻭﺩ‪ ،‬ﻧﻈﻴﺮ ﻳﮏ ﺳﺎﺧﺘﻤﺎﻥ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ WAN‬ﺗﻌﺪﺍﺩﻱ ﺩﺳﺘﮕﺎﻩ ﮐﻪ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﮐﻴﻠﻮﻣﺘﺮﻫﺎ ﻓﺎﺻﻠﻪ ﺩﺍﺭﻧﺪ ﺑﻪ ﻳﮑﺪﻳﮕﺮ‬ ‫ﻣﺘﺼﻞ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﻣﺜﻼ" ﺍﮔﺮ ﺩﻭ ﮐﺘﺎﺑﺨﺎﻧﻪ ﮐﻪ ﻫﺮ ﻳﮏ ﺩﺭ ﻳﮏ ﻧﺎﺣﻴﻪ ﺍﺯ ﺷﻬﺮ ﺑﺰﺭﮔﻲ ﻣﺴﺘﻘﺮ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻗﺼﺪ ﺍﺷﺘﺮﺍﮎ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺷﺒﮑﻪ ﺍﻱ ‪ WAN‬ﺍﻳﺠﺎﺩ ﻭ‬ ‫ﮐﺘﺎﺑﺨﺎﻧﻪ ﻫﺎ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪ .‬ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﺩﻭ ﮐﺘﺎﺑﺨﺎﻧﻪ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ‬

‫ﻣﺨﺎﺑﺮﺍﺗﻲ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ )‪ (Leased‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ‪LAN‬‬

‫ﻧﺴﺒﺖ ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ WAN‬ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ﺑﻴﺸﺘﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺎ ﺭﺷﺪ ﻭ ﺗﻮﺳﻌﻪ‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻣﻴﺰﺍﻥ ﺳﺮﻋﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ،WAN‬ﺗﻐﻴﻴﺮ ﻭ ﺑﻬﺒﻮﺩ ﭘﻴﺪﺍ ﮐﺮﺩﻩ‬

‫ﺍﺳﺖ‪ .‬ﺍﻣﺮﻭﺯﻩ ﺑﺎ ﺑﮑﺎﺭﮔﻴﺮﻱ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻌﺪﺩ ﮐﻪ ﺩﺭ ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ ﻧﺴﺒﺖ ﺑﻴﮑﺪﻳﮕﺮ ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪ ،‬ﻓﺮﺍﻫﻢ ﺷﺪﻩ‬ ‫ﺍﺳﺖ‪.‬‬

‫ﺍﺗﺮﻧﺖ‬ ‫ﺩﺭ ﺳﺎﻝ ‪ ١٩٧٣‬ﭘﮋﻭﻫﺸﮕﺮﻱ ﺑﺎ ﻧﺎﻡ " ‪ "Metcalfe‬ﺩﺭ ﻣﺮﮐﺰ ﺗﺤﻘﻴﻘﺎﺕ ﺷﺮﮐﺖ‬ ‫ﺯﻳﺮﺍﮐﺲ‪ ،‬ﺍﻭﻟﻴﻦ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ ﺭﺍ ﺑﻮﺟﻮﺩ ﺁﻭﺭﺩ‪ .‬ﻫﺪﻑ ﻭﻱ ﺍﺭﺗﺒﺎﻁ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮏ ﭼﺎﭘﮕﺮ‬

‫ﺑﻮﺩ‪ .‬ﻭﻱ ﺭﻭﺷﻲ ﻓﻴﺰﻳﮑﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﺎﺑﻞ ﮐﺸﻲ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﺼﻞ ﺑﻬﻢ ﺩﺭ ﺍﺗﺮﻧﺖ ﺍﺭﺍﺋﻪ‬ ‫ﻧﻤﻮﺩ‪ .‬ﺍﺗﺮﻧﺖ ﺩﺭ ﻣﺪﺕ ﺯﻣﺎﻥ ﮐﻮﺗﺎﻫﻲ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮑﻲ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﺭﺍﻳﺞ ﺑﺮﺍﻱ‬ ‫ﺑﺮﭘﺎﺳﺎﺯﻱ ﺷﺒﮑﻪ ﺩﺭ ﺳﻄﺢ ﺩﻧﻴﺎ ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﭘﻴﺸﺮﻓﺖ ﻫﺎﻱ ﻣﻬﻢ ﺩﺭ ﺯﻣﻴﻨﻪ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ‪ ،‬ﺗﺠﻬﻴﺰﺍﺕ ﻭ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﻧﻴﺰ ﻫﻤﮕﺎﻡ ﺑﺎ‬

‫ﺗﺤﻮﻻﺕ ﻓﻮﻕ ﺷﺪﻩ ﻭ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺩﺭ ﺑﻄﻦ ﺧﻮﺩ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫‪228‬‬

‫ﺗﻐﻴﻴﺮﺍﺕ ﻭ ﺍﺻﻼﺣﺎﺕ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ‪،‬ﻋﻤﻠﮑﺮﺩ ﻭ ﻧﺤﻮﻩ ﮐﺎﺭ ﺁﻧﺎﻥ ﻧﺴﺒﺖ‬

‫ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﺗﻔﺎﻭﺕ ﭼﻨﺪﺍﻧﻲ ﻧﮑﺮﺩﻩ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺍﺗﺮﻧﺖ ﺍﻭﻟﻴﻪ‪ ،‬ﺍﺭﺗﺒﺎﻁ ﺗﻤﺎﻡ ﺩﺳﺘﮕﺎﻩ‬ ‫ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﮐﺎﺑﻞ ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﺮﻓﺖ ﮐﻪ ﺗﻮﺳﻂ ﺗﻤﺎﻡ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺑﻪ‬ ‫ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﮔﺮﺩﻳﺪ‪ .‬ﭘﺲ ﺍﺯ ﺍﺗﺼﺎﻝ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺑﻪ ﮐﺎﺑﻞ ﻣﺸﺘﺮﮎ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺮﺑﻮﻃﻪ ﻧﻴﺰ ﺩﺭ ﺑﻄﻦ ﺩﺳﺘﮕﺎﻩ‬

‫ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ )ﮐﺎﺭﺕ ﺷﺒﮑﻪ (‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ ﮔﺴﺘﺮﺵ ﺷﺒﮑﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﭼﺪﻳﺪ ﺑﺮﺍﺣﺘﻲ ﺍﻧﺠﺎﻡ ﻭ ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﻋﻤﺎﻝ ﺗﻐﻴﻴﺮﺍﺕ ﺑﺮ ﺭﻭﻱ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺍﺗﺮﻧﺖ ﻳﮏ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻣﺤﻠﻲ )‪ (LAN‬ﺍﺳﺖ‪ .‬ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﺩﺭ ﺣﺪ ﻭ ﺍﻧﺪﺍﺯﻩ ﻳﮏ‬ ‫ﺳﺎﺧﺘﻤﺎﻥ ﺑﻮﺩﻩ ﻭ ﺩﺳﺘﮕﺎﻫﻬﺎ ﻧﺰﺩﻳﮏ ﺑﻪ ﻫﻢ ﺑﻮﺩﻧﺪ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﺍﺗﺮﻧﺖ ﺻﺮﻓﺎ" ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭼﻨﺪ ﺻﺪ ﻣﺘﺮ ﮐﺎﺑﻞ ﺑﻴﺸﺘﺮﻧﺒﻮﺩﻧﺪ‪.‬ﺍﺧﻴﺮﺍ" ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﻮﺳﻌﻪ‬ ‫ﺍﻣﮑﺎﻧﺎﺕ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻭ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﺯﻣﻴﻨﻪ ﺍﺳﺘﻘﺮﺍﺭ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ‬ ‫ﺑﺎ ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﭼﻨﺪ ﮐﻴﻠﻮﻣﺘﺮﻧﻴﺰ ﻓﺮﺍﻫﻢ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ‬

‫ﭘﺮﻭﺗﮑﻞ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻨﻲ ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﻧﺤﻮﻩ‬ ‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺭﺍ ﻗﺎﻧﻮﻧﻤﻨﺪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻧﻘﺶ ﭘﺮﻭﺗﮑﻞ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻧﻈﻴﺮ ﻧﻘﺶ ﺯﺑﺎﻥ ﺑﺮﺍﻱ ﺍﻧﺴﺎﻥ‬ ‫ﺍﺳﺖ‪ .‬ﺑﺮﺍﻱ ﻣﻄﺎﻟﻌﻪ ﻳﮏ ﮐﺘﺎﺏ ﻧﻮﺷﺘﻪ ﺷﺪﻩ ﺑﻪ ﻓﺎﺭﺳﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺧﻮﺍﻧﻨﺪﻩ ﺷﻨﺎﺧﺖ ﻣﻨﺎﺳﺒﻲ‬

‫ﺍﺯ ﺯﺑﺎﻥ ﻓﺎﺭﺳﻲ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﻣﻮﻓﻘﻴﺖ ﺁﻣﻴﺰ ﺩﻭ ﺩﺳﺘــﮕﺎﻩ ﺩﺭ ﺷــــﺒﮑﻪ‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﻫﺮ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﺍﺯ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﻣﺸﺎﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺍﺻﻄﻼﺣﺎﺕ ﺍﺗﺮﻧﺖ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻦ ﻣﺤﺪﻭﺩﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﻗﺎﻧﻮﻧﻤﻨﺪ ﮐﺮﺩﻥ ﻋﻤﻠﻴﺎﺕ‬

‫ﺍﺳﺎﺳﻲ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﻣﻨﺎﺳﺐ ﻗﻮﺍﻧﻴﻦ ﻣﻮﺟﻮﺩ ﻻﺯﻡ ﺍﺳﺖ ﮐﻪ‬ ‫ﺑﺎ ﺑﺮﺧﻲ ﺍﺯ ﺍﺻﻄﻼﺣﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﻴﺸﺘﺮ ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪:‬‬

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‫‪) Medium‬ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ( ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺍﺗﺮﻧﺖ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ‬

‫•‬

‫‪) Segment‬ﺳﮕﻤﻨﺖ ( ‪ .‬ﺑﻪ ﻳﮏ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﻣﻨﻔﺮﺩ‪" ،‬‬

‫ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﺳﮕﻤﻨﺖ " ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬

‫•‬

‫‪ ) Node‬ﮔﺮﻩ ( ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻳﮏ ‪ Segment‬ﺭﺍ ﮔﺮﻩ ﻭ ﻳﺎ "‬ ‫ﺍﻳﺴﺘﮕﺎﻩ " ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬

‫•‬

‫‪) Frame‬ﻓﺮﻳﻢ( ‪ .‬ﺑﻪ ﻳﮏ ﺑﻼﮎ ﺍﻃﻼﻋﺎﺕ ﮐﻪ ﮔﺮﻩ ﻫﺎ ﺍﺯ ﻃﺮﻳﻖ ﺍﺭﺳﺎﻝ ﺁﻧﻬﺎ ﺑﺎ‬ ‫ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ‬

‫ﻓﺮﻳﻢ ﻫﺎ ﻣﺸﺎﺑﻪ ﺟﻤﻼﺕ ﺩﺭ ﺯﺑﺎﻧﻬﺎﻱ ﻃﺒﻴﻌﻲ ) ﻓﺎﺭﺳﻲ‪ ،‬ﺍﻧﮕﻠﻴﺴﻲ ‪ ( ...‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﻫﺮ ﺯﺑﺎﻥ‬ ‫ﻃﺒﻴﻌﻲ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺟﻤﻼﺕ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻨﻲ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﻣﺜﻼ" ﻳﮏ ﺟﻤﻠﻪ ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫ﺩﺍﺭﺍﻱ ﻣﻮﺿﻮﻉ ﻭ ﻣﻔﻬﻮﻡ ﺑﺎﺷﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻦ ﻻﺯﻡ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻓﺮﻳﻢ‬

‫ﻫﺎ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ‪.‬ﺍﻧﺪﺍﺯﻩ ﻳﮏ ﻓﺮﻳﻢ ﻣﺤﺪﻭﺩ ﺑﻮﺩﻩ ) ﺩﺍﺭﺍﻱ ﻳﮏ ﺣﺪﺍﻗﻞ ﻭ ﻳﮏ‬ ‫ﺣﺪﺍﮐﺜﺮ ( ﻭ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺿﺮﻭﺭﻱ ﻭ ﻣﻮﺭﺩ ﻧﻴﺎﺭ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﻓﺮﻳﻢ ﻭﺟﻮﺩ‬ ‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﻣﺜﻼ" ﻳﮏ ﻓﺮﻳﻢ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺑﺎﺷﺪ‪ .‬ﺁﺩﺭﺱ‬

‫ﻫﺎﻱ ﻓﻮﻕ ﻫﻮﻳﺖ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﭘﻴﺎﻡ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺁﺩﺭﺱ ﺑﺼﻮﺭﺕ‬ ‫ﮐﺎﻣﻼ" ﺍﺧﺘﺼﺎﺻﻲ ﻳﮏ ﮔﺮﻩ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ).‬ﻧﻈﻴﺮ ﻧﺎﻡ ﻳﮏ ﺷﺨﺺ ﮐﻪ ﺑﻴﺎﻧﮕﺮ ﻳﮏ‬ ‫ﺷﺨﺺ ﺧﺎﺹ ﺍﺳﺖ (‪ .‬ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﻣﺘﻔﺎﻭﺕ ﺍﺗﺮﻧﺖ ﻧﻤﻲ ﺗﻮﺍﻧﻨﺪ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ﻫﺎﻱ ﻳﮑﺴﺎﻧﻲ‬

‫ﺑﺎﺷﻨﺪ‪.‬‬

‫ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺍﺗﺮﻧﺖ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺩﺭ ﻣﺤﻴﻂ‬ ‫ﺍﻧﺘﻘﺎﻝ ﺧﻮﺍﻫﺪ ﺭﺳﻴﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﺸﺨﺺ ﺷﺪﻥ ﺁﺩﺭﺱ ﻣﻘﺼﺪ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭﺩﺭﻳﺎﻓﺖ ﭘﻴﺎﻡ ﻧﻘﺸﻲ‬

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‫ﺣﻴﺎﺗﻲ ﺩﺍﺭﺩ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ) B‬ﺷﮑﻞ ﺑﺎﻻ( ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﭼﺎﭘﮕﺮ ‪C‬‬

‫ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ‪ A‬ﻭ ‪ D‬ﻧﻴﺰ ﻓﺮﻳﻢ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺁﻥ ﺭﺍ ﺑﺮﺭﺳﻲ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬

‫ﻫﺮ ﺍﻳﺴﺘﮕﺎﻩ ﺯﻣﺎﻧﻴﮑﻪ ﻓﺮﻳﻢ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﺩﺍﺭﺩ‪ ،‬ﺁﺩﺭﺱ ﺁﻥ ﺭﺍ ﺑﺮﺭﺳﻲ ﺗﺎ ﻣﻄﻤﺌﻦ ﮔﺮﺩﺩ ﮐﻪ‬ ‫ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﻭﻱ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺍﺳﺖ ﻳﺎ ﺧﻴﺮ؟ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﺍﻳﺴﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ‬

‫ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺍﻳﺴﺘﮕﺎﻩ ﻓﺮﻳﻢ ﺭﺍ ﺑﺪﻭﻥ ﺑﺮﺭﺳﻲ ﻣﺤﺘﻮﻳﺎﺕ ﺁﻥ ﮐﻨﺎﺭﺧﻮﺍﻫﺪﮔـــﺬﺍﺷﺖ)ﻋﺪﻡ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ (‪.‬‬ ‫ﻳﮑﻲ ﺍﺯ ﻧﮑﺎﺕ ﻗﺎﺑﻞ ﺗﻮﺟﻪ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺁﺩﺭﺱ ﺩﻫﻲ ﺍﺗﺮﻧﺖ‪ ،‬ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻳﮏ ﺁﺩﺭﺱ‬ ‫‪ Broadcast‬ﺍﺳﺖ ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﻳﮏ ﻓﺮﻳﻢ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺑﺎﺷﺪ‪ ،‬ﺗﻤﺎﻡ‬ ‫ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺁﻥ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﭘﺮﺩﺍﺯﺵ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪.‬‬ ‫‪CSMA/CD‬‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ‪carrier-sense multiple access with collision( CSMA/CD‬‬ ‫‪ ( detection‬ﻣﺴﺌﻮﻟﻴﺖ ﺗﺸﺮﻳﺢ ﻭ ﺗﻨﻈﻴﻢ ﻧﺤﻮﻩ ﺍﺭﺗﺒﺎﻁ ﮔﺮﻩ ﻫﺎ ﺑﺎ ﻳﮑﺪﻳﮕﺮﺭﺍ ﺑﺮﻋﻬﺪﻩ‬ ‫ﺩﺍﺭﺩ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ ﻭﺍﮊﻩ ﻓﻮﻕ ﭘﻴﭽﻴﺪﻩ ﺑﻨﻈﺮ ﻣﻲ ﺁﻳﺪ ﻭﻟﻲ ﺑﺎ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩﻥ ﻭﺍﮊﻩ ﻓﻮﻕ ﺑﻪ ﺑﺨﺶ ﻫﺎﻱ‬

‫ﮐﻮﭼﮑﺘﺮ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﻧﻘﺶ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﻬﺎ ﺳﺮﻳﻌﺘﺮ ﺁﺷﻨﺎ ﮔﺮﺩﻳﺪ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﻣﺜﺎﻝ ﺯﻳﺮ ﺭﺍ ﺩﻧﺒﺎﻝ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪.‬‬ ‫ﻓﺮﺽ ﮐﻨﻴﺪ ﺳﮕﻤﻨﺖ ﺍﺗﺮﻧﺖ‪ ،‬ﻣﺸﺎﺑﻪ ﻳﮏ ﻣﻴﺰ ﻧﺎﻫﺎﺭﺧﻮﺭﻱ ﺑﺎﺷﺪ‪ .‬ﭼﻨﺪﻳﻦ ﻧﻔﺮ )ﻧﻈﻴﺮ ﮔﺮﻩ(‬ ‫ﺩﻭﺭ ﺗﺎ ﺩﻭﺭ ﻣﻴﺰ ﻧﺸﺴﺘﻪ ﻭ ﺑﻪ ﮔﻔﺘﮕﻮ ﻣﺸﻐﻮﻝ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻭﺍﮊﻩ ‪multiple access‬‬

‫)ﺩﺳﺘﻴﺎﺑﻲ ﭼﻨﺪﮔﺎﻧﻪ( ﺑﺪﻳﻦ ﻣﻔﻬﻮﻡ ﺍﺳﺖ ﮐﻪ ‪ :‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺍﺗﺮﻧﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺍﺭﺳﺎﻝ‬ ‫ﻣﻲ ﺩﺍﺭﺩ ﺗﻤﺎﻡ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﺩﻳﮕﺮ ﻣﻮﺟﻮﺩ ) ﻣﺘﺼﻞ ( ﺩﺭ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ‪ ،‬ﻧﻴﺰ ﺍﺯ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺁﮔﺎﻩ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.).‬ﻧﻈﻴﺮ ﺻﺤﺒﺖ ﮐﺮﺩﻥ ﻳﮏ ﻧﻔﺮ ﺩﺭ ﻣﻴﺰ ﻧﺎﻫﺎﺭ ﺧﻮﺭﻱ ﻭ ﮔﻮﺵ ﺩﺍﺩﻥ ﺳﺎﻳﺮﻳﻦ‬ ‫(‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﮐﻪ ﺷﻤﺎ ﻧﻴﺰ ﺑﺮ ﺭﻭﻱ ﻳﮑﻲ ﺍﺯ ﺻﻨﺪﻟﻲ ﻫﺎﻱ ﻣﻴﺰ ﻧﺎﻫﺎﺭ ﺧﻮﺭﻱ ﻧﺸﺴﺘﻪ ﻭ ﻗﺼﺪ‬ ‫ﺣﺮﻑ ﺯﺩﻥ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪ ،‬ﺩﺭ ﻫﻤﺎﻥ ﺯﻣﺎﻥ ﻓﺮﺩ ﺩﻳﮕﺮﻱ ﺩﺭ ﺣﺎﻝ ﺳﺨﻦ ﮔﻔﺘﻦ ﺍﺳﺖ ﺩﺭ ﺍﻳﻦ‬ ‫ﺣﺎﻟﺖ ﻣﻲ ﺑﺎﻳﺴﺖ ﺷﻤﺎ ﺩﺭ ﺍﻧﺘﻈﺎﺭ ﺍﺗﻤﺎﻡ ﺳﺨﻨﺎﻥ ﮔﻮﻳﻨﺪﻩ ﺑﺎﺷﻴﺪ‪ .‬ﺩﺭ ﭘﺮﻭﺗﮑﻞ ﺍﺗﺮﻧﺖ ﻭﺿﻌﻴﺖ‬

‫ﻓﻮﻕ ‪ carrier sense‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪.‬ﻗﺒﻞ ﺍﺯ ﺍﻳﻨﮑﻪ ﺍﻳﺴﺘﮕﺎﻫﻲ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

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‫ﺑﺎﺷﺪ ﻣﻲ ﺑﺎﻳﺴﺖ ﮔﻮﺵ ﺧﻮﺩ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﮔﺬﺍﺷﺘﻪ ﻭ ﺑﺮﺭﺳﻲ ﻧﻤﺎﻳﺪ ﮐﻪ ﺁﻳﺎ ﻣﺤﻴﻂ‬ ‫ﺍﻧﺘﻘﺎﻝ ﺁﺯﺍﺩ ﺍﺳﺖ؟ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺻﺪﺍﺋﻲ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﮔﻮﺵ ﺍﻳﺴﺘﮕﺎﻩ ﻣﺘﻘﺎﺿﻲ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﻧﺮﺳﺪ‪ ،‬ﺍﻳﺴﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫‪ access Carrier-sense multiple‬ﺷــﺮﻭﻉ ﻳﮏ ﮔﻔﺘﮕﻮ ﺭﺍ ﻗﺎﻧﻮﻧﻤﻨﺪ ﻭ ﺗﻨﻈــﻴﻢ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻳﮏ ﻧﮑﺘﻪ ﺩﻳﮕﺮ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮﺍﻱ ﺁﻥ ﻧﻴﺰ‬ ‫ﺭﺍﻫﮑﺎﺭﻱ ﺍﺗﺨﺎﺫ ﺷﻮﺩ‪.‬ﻓﺮﺽ ﮐﻨﻴﺪ ﺩﺭ ﻣﺜﺎﻝ ﻣﻴﺰ ﻧﺎﻫﺎﺭ ﺧﻮﺭﻱ ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺳﮑﻮﺗﻲ ﺣﺎﮐﻢ‬

‫ﺷﻮﺩ ﻭ ﺩﻭ ﻧﻔﺮ ﻧﻴﺰ ﻗﺼﺪ ﺣﺮﻑ ﺯﺩﻥ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪.‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺳﮑﻮﺕ‬ ‫ﻣﻮﺟﻮﺩ ﺗﻮﺳﻂ ﺩﻭ ﻧﻔﺮ ﺗﺸﺨﻴﺺ ﻭ ﺑﻼﻓﺎﺻﻠﻪ ﻫﺮ ﺩﻭ ﺗﻘﺮﻳﺒﺎ" ﺩﺭ ﻳﮏ ﺯﻣﺎﻥ ﻳﮑﺴﺎﻥ ﺷﺮﻭﻉ‬

‫ﺑﻪ ﺣﺮﻑ ﺯﺩﻥ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬ﭼﻪ ﺍﺗﻔﺎﻗﻲ ﺧﻮﺍﻫﺪ ﺍﻓﺘﺎﺩ؟ ﺩﺭ ﺍﺗﺮﻧﺖ ﭘﺪﻳﺪﻩ ﻓﻮﻕ ﺭﺍ ﺗﺼﺎﺩﻡ‬

‫)‪ (Collision‬ﻣﻲ ﮔﻮﻳﻨﺪ ﻭ ﺯﻣﺎﻧﻲ ﺍﺗﻔﺎﻕ ﺧﻮﺍﻫﺪ ﺍﻓﺘﺎﺩ ﮐﻪ ﺩﻭ ﺍﻳﺴﺘﮕﺎﻩ ﻗﺼﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﮔﻔﺘﮕﻮﻱ ﺍﻧﺴﺎﻥ ﻫﺎ‪،‬‬

‫ﻣﺸﮑﻞ ﻓﻮﻕ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺼﻮﺭﺕ ﮐﺎﻣﻼ" ﺩﻭﺳﺘﺎﻧﻪ ﺣﻞ ﻧﻤﻮﺩ‪ .‬ﻣﺎ ﺳﮑﻮﺕ ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ ﺗﺎ ﺍﻳﻦ‬ ‫ﺷﺎﻧﺲ ﺑﻪ ﺳﺎﻳﺮﻳﻦ ﺑﺮﺍﻱ ﺣﺮﻑ ﺯﺩﻥ ﺩﺍﺩﻩ ﺷﻮﺩ‪ .‬ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺯﻣﺎﻥ ﺣﺮﻑ ﺯﺩﻥ ﻣﻦ‪،‬‬ ‫ﺩﻳﮕﺮﺍﻥ ﺍﻳﻦ ﻓﺮﺻﺖ ﺭﺍ ﺑﺮﺍﻱ ﻣﻦ ﺍﻳﺠﺎﺩ ﮐﺮﺩﻩ ﺑﻮﺩﻧﺪ! ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﺍﺗﺮﻧﺖ ﺯﻣﺎﻧﻴﮑﻪ ﻗﺼﺪ‬ ‫ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﮔﻮﺵ ﻓﺮﺍ ﺩﺍﺩﻩ ﺗﺎ ﺑﻪ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺑﺮﺳﻨﺪ‬ ‫ﮐﻪ ﺗﻨﻬﺎ ﺍﻳﺴﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ‬

‫ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ ﻣﺘﻮﺟﻪ ﻧﻘﺺ ﺩﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺩ ﮔﺮﺩﻧﺪ‪ ،‬ﺍﺯ ﺑﺮﻭﺯ ﻳﮏ ﺗﺼﺎﺩﻡ‬ ‫ﺩﺭ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺁﮔﺎﻩ ﺧﻮﺍﻫﻨﺪ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺑﺮﻭﺯ ﺗﺼﺎﺩﻡ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ‬

‫ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﻣﺪﺕ ﺯﻣﺎﻧﻲ ﮐﺎﻣﻼ" ﺗﺼﺎﺩﻓﻲ ﺩﺭ ﺣﺎﻟﺖ ﺍﻧﺘﻈﺎﺭ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﭘﺲ ﺍﺯ ﺍﺗﻤﺎﻡ ﺯﻣﺎﻥ‬

‫ﺍﻧﺘﻈﺎﺭ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺷﺮﻁ ﺁﺯﺍﺩ ﺑﻮﺩﻥ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﺑﺮﺭﺳﻲ ﻧﻤﺎﻳﻨﺪ!‬

‫ﺗﻮﻗﻒ ﺗﺼﺎﺩﻓﻲ ﻭ ﺗﻼﺵ ﻣﺠﺪﺩ ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﺑﺨﺶ ﻫﺎﻱ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺖ‪.‬‬

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‫ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ﺍﺗﺮﻧﺖ‬

‫ﻳﮏ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ ﺩﺍﺭﺍﻱ ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺯ ﺍﺑﻌﺎﺩ ﮔﻮﻧﺎﮔﻮﻥ )ﺑﮑﺎﺭﮔﻴﺮﻱ‬

‫ﺗﺠﻬﻴﺰﺍﺕ ( ﺍﺳﺖ‪ .‬ﻃﻮﻝ ﮐﺎﺑﻠﻲ ﮐﻪ ﺗﻤﺎﻡ ﺍﻳﺴﺘﮕﺎﻫﻬﺎ ﺑﺼﻮﺭﺕ ﺍﺷﺘﺮﺍﮐﻲ ﺍﺯ ﺁﻥ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺤﻴﻂ‬

‫ﺍﻧﺘﻘﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﻳﮑﻲ ﺍﺯ ﺷﺎﺧﺺ ﺗﺮﻳﻦ ﻣﻮﺍﺭﺩ ﺩﺭ ﺍﻳﻦ ﺯﻣﻨﻴﻪ ﺍﺳﺖ‪ .‬ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ‬

‫ﺍﻟﮑﺘﺮﻳﮑﻲ ﺩﺭ ﻃﻮﻝ ﮐﺎﺑﻞ ﺑﺴﺮﻋﺖ ﻣﻨﺘﺸﺮ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻃﻲ ﻣﺴﺎﻓﺘﻲ‪ ،‬ﺳﻴﮕﻨﺎﻝ ﻫﺎ‬ ‫ﺿﻌﻴﻒ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻭﭼﻮﺩ ﻣﻴﺪﺍﻥ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﮐﻪ ﺗﻮﺳﻂ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺠﺎﻭﺭ ﮐﺎﺑﻞ‬ ‫ﻧﻈﻴﺮﻻﻣﭗ ﻫﺎﻱ ﻓﻠﻮﺭﺳﻨﺖ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺑﺎﻋﺚ ﺗﻠﻒ ﺷﺪﻥ ﺳﻴﮕﻨﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻃﻮﻝ‬

‫ﮐﺎﺑﻞ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﮐﻮﺗﺎﻩ ﺑﻮﺩﻩ ﺗﺎ ﺍﻣﮑﺎﻥ ﺩﺭﻳﺎﻓﺖ ﺳﻴﮕﻨﺎﻝ ﺗﻮﺳﻂ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺩﻭ ﻧﻘﻄﻪ ﺍﺑﺘﺪﺍﺋﻲ ﻭ ﺍﻧﺘﻬﺎﺋﻲ ﮐﺎﺑﻞ ﺑﺼﻮﺭﺕ ﺷﻔﺎﻑ ﻭ ﺑﺎ ﺣﺪﺍﻗﻞ ﺗﺎﺧﻴﺮ ﺯﻣﺎﻧﻲ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬

‫ﻫﻤﻴﻦ ﺍﻣﺮ ﺑﺎﻋﺚ ﺑﺮﻭﺯ ﻣﺤﺪﻭﺩﻳﺖ ﺩﺭ ﻃﻮﻝ ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‪ ،‬ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ‪ CSMA/CD‬ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﺻﺮﻓﺎ" ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺭﺍ ﺩﺭ ﻫﺮ ﻟﺤﻈﻪ‬

‫ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﺋﻲ ﺍﺯ ﻟﺤﺎﻅ ﺗﻌﺪﺍﺩ ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ ﮐﻪ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺮ‬ ‫ﺭﻭﻱ ﻳﮏ ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﻧﻴﺰ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺁﻣﺪ‪ .‬ﺑﺎ ﺍﺗﺼﺎﻝ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ‬

‫ﻣﺘﻌﺪﺩ )ﻓﺮﺍﻭﺍﻥ ( ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﺸﺘﺮﮎ‪ ،‬ﺷﺎﻧﺲ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﺮﺍﻱ ﻫﺮ‬ ‫ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺳﮕﻤﻨﺖ ﮐﺎﻫﺶ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﻫﺮ‬ ‫ﺩﺳﺘﮕﺎﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺪﺕ ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ ﺭﺍ ﺩﺭ ﺍﻧﺘﻈﺎﺭ ﺳﭙﺮﻱ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺗﺠﻬﻴﺰﺍﺕ ﺷﺒﮑﻪ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﻏﻠﺒﻪ ﺑﺮ ﻣﺸﮑﻼﺕ ﻭ‬

‫ﻣﺤﺪﻭﺩﻳﺖ ﮔﻔﺘﻪ ﺷﺪﻩ‪ ،‬ﻃﺮﺍﺣﻲ ﻭ ﻋﺮﺿﻪ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﺍﻏﻠﺐ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻓﻮﻕ ﻣﺨﺘﺺ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﻧﺒﻮﺩﻩ ﻭﻟﻲ ﺩﺭ ﺳﺎﻳﺮ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﺷﺒﮑﻪ ﻧﻘﺶ ﻣﻬﻤﻲ ﺭﺍ ﺍﻳﻔﺎﺀ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ )‪(Repeater‬‬

‫ﺍﻭﻟﻴﻦ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﺴﻲ ﮐﻮﺍﮐﺴﻴﺎﻝ ﺑﻮﺩ‬

‫ﮐﻪ ‪ ) Thicknet‬ﺿﺨﻴﻢ( ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺣﺪﺍﮐﺜﺮ ﻃﻮﻝ ﻳﮏ ﮐﺎﺑﻞ ﺿﺨﻴﻢ ‪ ٥٠٠‬ﻣﺘﺮ ﺍﺳﺖ‬ ‫‪ .‬ﺩﺭ ﻳﮏ ﺳﺎﺧﺘﻤﺎﻥ ﺑﺰﺭﮒ ‪ ،‬ﮐﺎﺑﻞ ‪ ٥٠٠‬ﻣﺘﺮﻱ ﺟﻮﺍﺑﮕﻮﻱ ﺗﻤﺎﻣﻲ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺷﺒﮑﻪ ﻧﺨﻮﺍﻫﺪ‬ ‫‪233‬‬

‫ﺑﻮﺩ‪ .‬ﺗﮑﺮﺍﺭ ﮐﻨﻨﺪﻩ ﻫﺎ ﺑﺎ ﻫﺪﻑ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ‪ ،‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﻧﺪ‪ . .‬ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ﻫﺎ ‪ ،‬ﺳﮕﻤﻨﺖ‬

‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻳﮏ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮐﻨﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ‬ ‫ﺳﻴﮕﻨﺎﻝ ﻭﺭﻭﺩﻱ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﻳﮏ ﺳﮕﻤﻨﺖ ﺍﺧﺬ ﻭ ﺑﺎ ﺗﻘﻮﻳﺖ ﺳﻴﮕﻨﺎﻝ ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ‬

‫ﺑﻌﺪﻱ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺰﺗﻴﺐ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭼﻨﺪﻳﻦ ﺗﮑﺮﺍﺭ ﮐﻨﻨﺪﻩ ﻭ ﺍﺗﺼﺎﻝ ﮐﺎﺑﻞ‬

‫ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺗﻮﺳﻂ ﺁﻧﺎﻥ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﻗﻄﺮ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﺍﻓﺰﺍﻳﺶ ﺩﺍﺩ‪ ) .‬ﻗﻄﺮ ﺷﺒﮑﻪ ﺑﻪ ﺣﺪﺍﮐﺜﺮ‬

‫ﻣﺴﺎﻓﺖ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﻣﺘﻤﺎﻳﺰ ﺩﺭ ﺷﺒﮑﻪ ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ(‬ ‫‪ Bridges‬ﻭ ﺳﮕﻤﻨﺖ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﺷﺪ )ﺑﺰﺭﮒ ﺷﺪﻥ( ﺩﭼﺎﺭ ﻣﺸﮑﻞ ﺗﺮﺍﮐﻢ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ‬

‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﻳﺴﺘﮕﺎﻩ ﺑﻪ ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﺘﺼﻞ ﮔﺮﺩﻧﺪ‪ ،‬ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﻱ ﺗﺮﺍﻓﻴﮏ‬ ‫ﺧﺎﺹ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺷﺮﺍﻳﻂ ﻓﻮﻕ ‪ ،‬ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻌﺪﺩﻱ ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼ ﻋﺎﺕ‬ ‫ﺭﺍ ﺩﺍﺭﻧﺪ ﻭﻟﻲ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺎﻫﻴﺖ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﺩﺭ ﻫﺮ ﻟﺤﻈﻪ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺷﺎﻧﺲ ﻭ‬

‫ﻓﺮﺻﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﺗﻌﺪﺍﺩ ﺗﺼﺎﺩﻡ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﺍﻓﺰﺍﻳﺶ ﻳﺎﻓﺘﻪ ﻭ ﻋﻤﻼ" ﮐﺎﺭﺁﺋﻲ ﺷﺒﮑﻪ ﺍﻓﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻳﮑﻲ ﺍﺯ ﺭﺍﻩ ﺣﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻥ ﻣﺸﮑﻞ ﺗﺮﺍﮐﻢ ﺩﺭ ﺷﺒﮑﻪ ﺗﻘﺴﻴﻢ ﻳﮏ ﺳﮕﻤﻨﺖ ﺑﻪ ﭼﻨﺪﻳﻦ ﺳﮕﻤﻨﺖ‬

‫ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﻳﻦ ﮐﺎﺭ ﺑﺮﺍﻱ ﺗﺼﺎﺩﻡ ﻫﺎﺋﻲ ﮐﻪ ﺩﺭ ﺷﺒﮑﻪ ﺑﺮﻭﺯ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ،‬ﺩﺍﻣﻨﻪ ﻭﺳﻴﻌﺘﺮﻱ ﺍﻳﺠﺎﺩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪.‬ﺭﺍﻩ ﺣﻞ ﻓﻮﻕ ﺑﺎﻋﺚ ﺑﺮﻭﺯ ﻳﮏ ﻣﺸﮑﻞ ﺩﻳﮕﺮ ﻣﻲ ﮔﺮﺩﺩ‪ :‬ﺳﮕﻤﻨﺖ ﻫﺎ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﺷﺘﺮﺍﮎ ﺍﻃﻼﻋﺎﺕ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ‪ Bridges ،‬ﺩﺭ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﺳﺖ ‪Bridge .‬‬ ‫ﺩﻭ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﺳﮕﻤﻨﺖ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ‬ ‫ﺑﺎﻋﺚ ﺍﻓﺰﺍﻳﺶ ﻗﻄﺮ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻋﻤﻠﮑﺮﺩ ‪ Bridge‬ﺍﺯ ﺑﻌﺪ ﺍﻓﺰﺍﻳﺶ ﻗﻄﺮ ﺷﺒﮑﻪ ﻧﻈﻴﺮ‬ ‫ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ﺍﺳﺖ‪ ،‬ﺑﺎ ﺍﻳﻦ ﻧﻔﺎﻭﺕ ﮐﻪ ‪ Bridge‬ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻧﻈﻢ ﺩﺭ ﺗﺮﺍﻓﻴﮏ ﺷﺒﮑﻪ ﻧﻴﺰ‬

‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ Bridge .‬ﻧﻈﻴﺮ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ‬

‫ﺍﻃﻼﻋﺎﺕ ﺑﻮﺩﻩ ﻭﻟﻲ ﻋﻤﻠﮑﺮﺩ ﺁﻧﻬﺎ ﺩﻗﻴﻘﺎ" ﻣﺸﺎﺑﻪ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﻧﻤﻲ ﺑﺎﺷﺪ‪ Bridge .‬ﻗﺎﺩﺭ ﺑﻪ‬ ‫‪234‬‬

‫ﺍﻳﺠﺎﺩ ﺗﺮﺍﻓﻴﮑﻲ ﮐﻪ ﺧﻮﺩ ﺳﺮﭼﺸﻤﻪ ﺁﻥ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ ،‬ﻧﻴﺴﺖ ) ﻧﻈﻴﺮ ﺗﮑﺮﺍﺭﮐﻨﻨﺪﻩ ( ‪Bridge.‬‬

‫ﺻﺮﻓﺎ" ﭼﻴﺰﻱ ﺭﺍ ﮐﻪ ﺍﺯ ﺳﺎﻳﺮ ﺍﻳﺴﺘﮕﺎﻫﻬﺎ ﻣﻲ ﺷﻨﻮﺩ‪ ،‬ﻣﻨﻌﮑﺲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ Bridge ) .‬ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﻳﺠﺎ ﺩ ﻳﮏ ﻧﻮﻉ ﻓــﺮﻳﻢ ﺧﺎﺹ ﺍﺗﺮﻧﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳـــﺠﺎﺩ ﺍﺭﻧﺒـﺎﻁ ﺑﺎ ﺳــﺎﻳﺮ ‪ Bridge‬ﻫﺎ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ (‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻗﺒﻼ" ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ ﻫﺮ ﺍﻳﺴﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺗﻤﺎﻡ ﻓﺮﻳﻢ ﻫﺎﻱ ﺍﺭﺳﺎﻝ ﺷﺪﻩ‬

‫ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪).‬ﺻﺮﻓﻨﻈﺮ ﺍﺯﺍﻳﻨﮑﻪ ﻣﻘﺼﺪ ﻓﺮﻳﻢ ﻫﻤﺎﻥ ﺍﻳﺴﺘﮕﺎﻩ‬ ‫ﺑﺎﺷﺪ ﻭ ﻳﺎ ﻧﺒﺎﺷﺪ‪ Bridge (.‬ﺑﺎ ﺗﺎﮐﻴﺪ ﺑﺮ ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺳﻌﻲ ﺑﺮ ﺗﻨﻈﻴﻢ ﺗﺮﺍﻓﻴﮏ ﺑﻴﻦ ﺳﮕﻤﻨﺖ‬ ‫ﻫﺎ ﺩﺍﺭﺩ‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ Bridge‬ﺩﻭ ﺳﮕﻤﻨﺖ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ‬ ‫ﻧﻤﻮﺩﻩ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻳﺴﺘﮕﺎﻩ ‪ A‬ﻭ ﻳﺎ ‪ B‬ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‬

‫‪ Bridge‬ﻧﻴﺰ ﻓﺮﻳﻢ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ‪ Bridge‬ﺑﺎ ﻓﺮﻳﻢ‬

‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ ﺍﺳﺖ؟ ﺁﻳﺎ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﺗﻮﻣﺎﺗﻴﮏ ﻓﺮﻳﻢ ﻫﺎ‬ ‫ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ ﺩﻭﻡ ﻣﻲ ﺑﺎﺷﺪ؟ ﻳﮑﻲ ﺍﺯﺍﻫﺪﺍﻑ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ Bridge‬ﮐﺎﻫﺶ ﺗﺮﺍﻓﻴﮏ ﻫﺎﻱ‬

‫ﻏﻴﺮﺿﺮﻭﺭﻱ ﺩﺭ ﻫﺮ ﺳﮕﻤﻨﺖ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ‪ ،‬ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﻓﺮﻳﻢ ‪ ،‬ﻗﺒﻞ ﺍﺯ ﻫﺮ ﮔﻮﻧﻪ‬ ‫ﻋﻤﻠﻴﺎﺕ ﺑﺮ ﺭﻭﻱ ﺁﻥ‪ ،‬ﺑﺮﺭﺳﻲ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺁﺩﺭﺱ ﻣﻘﺼﺪ‪ ،‬ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ‪ A‬ﻭ‬

‫ﻳﺎ ‪ B‬ﺑﺎﺷﺪ ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﺭﺳﺎﻝ ﻓﺮﻳﻢ ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ ﺷﻤﺎﺭﻩ ﺩﻭ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺩﺭ ﺍﻳﻦ‬ ‫ﺣﺎﻟﺖ ‪ Bridge‬ﻋﻤﻠﻴﺎﺕ ﺧﺎﺻﻲ ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ‪ Bridge‬ﺑﺎ ﻓﺮﻳﻢ‬

‫ﻓﻮﻕ ﻣﺸﺎﺑﻪ ﻓﻴﻠﺘﺮ ﻧﻤﻮﺩﻥ ﺍﺳﺖ‪ .‬ﺩﺭﺻﻮﺭﺗﻲ ﮐﻪ ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﻓﺮﻳﻢ ﻳﮑﻲ ﺍﺯ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ‪C‬‬ ‫ﻭ ﻳﺎ ‪ D‬ﺑﺎﺷﺪ ﻭ ﻳﺎ ﻓﺮﻳﻢ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺑﺎﺷﺪ‪،‬‬ ‫‪ Bridge‬ﻓﺮﻳﻢ ﻓﻮﻕ ﺭﺍ ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ ﺷﻤﺎﺭﻩ ﺩﻭ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫ﺑﺎ ﺍﺭﺳﺎﻝ ﻭ ﻫﺪﺍﻳﺖ ﻓﺮﻳﻢ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ‪ Bridge‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﭼﻬﺎﺭ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﮑﺎﻧﻴﺰﻡ ﻓﻴﻠﺘﺮ ﻧﻤﻮﺩﻥ ﻓﺮﻳﻢ ﻫﺎ ﺗﻮﺳﻂ ‪ ، Bridge‬ﺍﻳﻦ‬

‫ﺍﻣﮑﺎﻥ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺁﻣﺪ ﮐﻪ ﺍﻳﺴﺘﮕﺎﻩ ‪ A‬ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﺍﻳﺴﺘﮕﺎﻩ ‪ B‬ﺍﺭﺳﺎﻝ ﻭ ﺩﺭ ﻫﻤﺎﻥ‬ ‫ﻟﺤﻈﻪ ﻧﻴﺰ ﺍﻳﺴﺘﮕﺎﻩ ‪ C‬ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﺍﻳﺴﺘﮕﺎﻩ ‪ D‬ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪.‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ‬

‫ﺑﺮﻗﺮﺍﺭﻱ ﺩﻭ ﺍﺭﺗﺒﺎﻁ ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎ ‪ :‬ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻣﻨﻄﻘﻲ‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ Bridge‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﻫﻤﺰﻣﺎﻥ ﺑﻴﻦ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﭼﻨﺪﻳﻦ‬

‫ﺳﮕﻤﻨﺖ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪ Bridge .‬ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺳﮕﻤﻨﺖ ﻋﻤﻠﻴﺎﺕ‬ ‫ﺧﺎﺻﻲ ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﻤﻲ ﺩﻫﺪ‪ .‬ﻳﮑﻲ ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻣﻬﻢ ‪ Bridge‬ﺍﺭﺳﺎﻟﻲ ﻓﺮﻳﻢ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺑﺮﺍﻱ ﺗﻤﺎﻡ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺖ‪.‬‬

‫ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﺷﺪ ﺷﺒﮑﻪ ﻭ ﮔﺴﺘﺮﺵ ﺳﮕﻤﻨﺖ ﻫﺎ‪ ،‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻧﺪ ﺳﺒﺐ ﺑﺮﻭﺯ ﻣﺴﺎﺋﻠﻲ‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﺯ ﺍﻳﺴﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫‪ ، Bridge‬ﻓﺮﻳﻢ ﻫﺎﻱ ‪ Broadcast‬ﺭﺍ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺗﺮﺍﮐﻢ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺟﻮﺩ ﺁﻣﺪﻩ‬

‫ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ ﺯﻣﺎﻧﻲ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ﮐﻪ ﺗﻤﺎﻣﻲ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺩﺭ ﻳﮏ ﺳﮕﻤﻨﺖ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ‬ ‫ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺭﻭﺗﺮ ﻳﮑﻲ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﭘﻴﺸﺮﻓﺘﻪ ﺩﺭ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﺗﻘﺴﻴﻢ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﭼﻨﺪﻳﻦ‬

‫ﺷﺒﮑﻪ ﻣﻨﻄﻘﻲ ﻣﺠﺰﺍ ﺍﺳﺖ‪ .‬ﺭﻭﺗﺮ ﻫﺎ ﻳﮏ ﻣﺤﺪﻭﺩﻩ ﻣﻨﻄﻘﻲ ﺑﺮﺍﻱ ﻫﺮ ﺷﺒﮑﻪ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎ ﺑﺮ ﺍﺳﺎﺱ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﮐﻪ ﻣﺴﺘﻘﻞ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺧﺎﺹ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ‪،‬‬ ‫ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺍﻳﻦ ﺍﻣﮑﺎﻥ ﺭﺍ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﮐﺮﺩ ﮐﻪ ﭼﻨﺪﻳﻦ‬ ‫ﺷﺒﮑﻪ ﺑﺎ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻧﻤﺎﻳﺪ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﻣﺤﻠﻲ ﻭ ﮔﺴﺘﺮﺩﻩ ﺍﻣﮑﺎﻥ ﭘﺬﻳﺮﺍﺳﺖ‪.‬‬

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‫ﻭﺿﻌﻴﺖ ﻓﻌﻠﻲ ﺍﺗﺮﻧﺖ‬

‫ﺍﺯ ﺯﻣﺎﻥ ﻣﻄﺮﺡ ﺷﺪﻥ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺗﺎﮐﻨﻮﻥ ﺗﻐﻴﻴﺮﺍﺕ ﻓﺮﺍﻭﺍﻧﻲ ﺍﺯ ﺑﻌﺪ ﺗﻨﻮﻉ‬

‫ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺍﺯ ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻝ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻳﺪ‪.‬ﺍﻣﺮﻭﺯﻩ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺪﺭﻥ ﺍﺗﺮﻧﺖ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﻭ ﻳﺎ ﻓﻴﺒﺮ‬ ‫ﻧﻮﺭﻱ ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﺍﻳﺴﺘﮕﺎﻩ ﻫﺎ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﺍﺗﺮﻧﺖ‬

‫ﺳﺮﻋﺖ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﻮﺩ ﻭﻟﻲ ﺍﻣﺮﻭﺯﻩ ﺍﻳﻦ ﺳﺮﻋﺖ ﺑﻪ ﻣﺮﺯ ‪١٠٠‬ﻭ‬

‫ﺣﺘﻲ ‪ ١٠٠٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺭﺳﻴﺪﻩ ﺍﺳﺖ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﺗﺤﻮﻝ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬

‫ﺍﺗﺮﻧﺖ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺍﺳﺖ ‪.‬ﺳﮕﻤﻨﺖ ﻫﺎ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ ﺑﻪ ﻳﮑﺪﻳﮕﺮ‬ ‫ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ) .‬ﻧﻈﻴﺮ ‪ Bridge‬ﺑﺎ ﺍﻳﻦ ﺗﻔﺎﻭﺕ ﻋﻤﺪﻩ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﭼﻨﺪﻳﻦ ﺳﮕﻤﻨﺖ‬

‫ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ( ﺑﺮﺧﻲ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﺻﺪﻫﺎ ﺳﮕﻤﻨﺖ ﺑﻪ‬ ‫ﻳﮑﺪﻳﮕﺮ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺗﻤﺎﻡ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﺳﻮﺋﻴﭻ ﻭ ﻳﺎ ﺍﻳﺴﺘﮕﺎﻩ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ ﻓﺮﻳﻢ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍ ﻱ ﻫﺮ ﺍﻳﺴﺘﮕﺎﻩ‪ ،‬ﺳﻮﺋﻴﭻ ﻓﺮﻳﻢ ﻣﻮﺭﺩ ﻧﻈﺮ‬

‫ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﭘﺲ ﺍﺯ ﺑﺮﺭﺳﻲ‪ ،‬ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﺍﻳﺴﺘﮕﺎﻩ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ‪ Bridge‬ﺍﺳﺖ‪ ،‬ﻭﻟﻲ ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻫﺮ ﺳﮕﻤﻨﺖ ﺩﺍﺭﺍﻱ ﺻﺮﻓﺎ" ﻳﮏ‬

‫ﺍﻳﺴﺘﮕﺎﻩ ﺍﺳﺖ ﻭ ﻓﺮﻳﻢ ﺻﺮﻓﺎ" ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻭﺍﻗﻌﻲ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‬ ‫ﺍﻣﮑﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﻫﻤﺰﻣﺎﻥ ﺑﻴﻦ ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﻳﺴﺘﮕﺎﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋــﻴﭻ‬

‫ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻣﻄﺮﺡ ﺷﺪﻥ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﻣﺴﺌﻠﻪ ‪ Full-duplex‬ﻧﻴﺰ ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪Full- .‬‬ ‫‪ dulled‬ﻳﮏ ﺍﺻﻄﻼﺡ ﺍﺭﺗﺒﺎﻃﻲ ﺍﺳﺖ ﮐﻪ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﻗﺎﺑﻠﻴﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺍﻭﻟﻴﻪ ﻭﺿﻌﻴﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ‬ ‫ﺑﺼﻮﺭﺕ ﻳﮑﻄﺮﻓﻪ )‪ (half-duplex‬ﺑﻮﺩ‪.‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ‪ ،‬ﺍﻳﺴﺘﮕﺎﻫﻬﺎ‬ ‫ﺻﺮﻓﺎ" ﺑﺎ ﺳﻮﺋﻴﭻ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﮐﺮﺩﻩ ﻭ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﻣﺴﺘﻘﻴﻢ ﺑﺎ ﻳﮑﺪﻳﮕﺮﻧﻤﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ‬ ‫ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﻭ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻭﺳﻮﺋﻴﭻ ﻣﺮﺑﻮﻃﻪ ﺩﺍﺭﺍﻱ‬ ‫ﮐﺎﻧﮑﻨﻮﺭﻫﺎﻱ ﻻﺯﻡ ﺩﺭ ﺍﻳﻦ ﺧﺼﻮﺹ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ ﻋﺎﺭﻱ ﺍﺯ ﺗﺼﺎﺩﻡ‬ ‫‪237‬‬

‫ﺑﻮﺩﻩ ﻭ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﺑﻪ ﺳﻮﺋﻴﭻ ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

‫ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ ﺑﺮﺍﻱ ﺍﻳﺴﺘﮕﺎﻩ ﺩﻳﮕﺮ ﻧﻴﺰ ﻓﺮﺍﻫﻢ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺍﺗﺮﻧﺖ ﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪٨٠٢,٣‬‬

‫ﺷﺎﻳﺪ ﺗﺎﮐﻨﻮﻥ ﺍﺻﻄﻼﺡ ‪ ٨٠٢,٣‬ﺭﺍ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺷﻨﻴﺪﻩ ﺑﺎﺷﻴﺪ‪ .‬ﺍﺗﺮﻧﺖ‬

‫ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺷﺒﮑﻪ ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﻫﺎﻱ‪ :‬ﺩﻳﺠﻴﺘﺎﻝ‪ ،‬ﺍﻳﻨﺘﻞ ﻭ ﺯﻳﺮﺍﮐﺲ )‪(DIX‬‬

‫ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٠‬ﻣﻮﺳﺴﻪ ‪ IEEE‬ﮐﻤﻴﺘﻪ ﺍﻱ ﺭﺍ ﻣﺴﺌﻮﻝ ﺍﺳﺘﺎﻧﺪﺍﺭ ﺳﺎﺯﻱ‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﺷﺒﮑﻪ ﮐﺮﺩ‪ .‬ﻣﻮﺳﺴﻪ ‪ IEEE‬ﻧﺎﻡ ﮔﺮﻭﻩ ﻓﻮﻕ ﺭﺍ ‪ ٨٠٢‬ﻗﺮﺍﺭ ﺩﺍﺩ‪.‬‬ ‫) ﻋﺪﺩ ‪ ٨٠٢‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺳﺎﻝ ﻭ ﻣﺎﻩ ﺗﺸﮑﻴﻞ ﮐﻤﻴﺘﻪ ﺍﺳﺘﺎﻧﺪﺍﺭﺳﺎﺯﻱ ﺍﺳﺖ ( ﮐﻤﻴﺘﻪ ﻓﻮﻕ ﺍﺯ‬

‫ﭼﻨﺪﻳﻦ ﮐﻤﻴﺘﻪ ﺟﺎﻧﺒﻲ ﺩﻳﮕﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺑﻮﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﻤﻴﺘﻪ ﻫﺎﻱ ﻓﺮﻋﻲ ﻧﻴﺰ ﻣﺴﺌﻮﻝ‬

‫ﺑﺮﺭﺳﻲ ﺟﻨﺒﻪ ﻫﺎﻱ ﺧﺎﺻﻲ ﺍﺯ ﺷﺒﮑﻪ ﮔﺮﺩﻳﺪﻧﺪ‪ .‬ﻣﻮﺳﺴﻪ ‪ IEEE‬ﺑﺮﺍﻱ ﺗﻤﺎﻳﺰ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﻤﻴﺘﻪ‬ ‫ﻫﺎﻱ ﺟﺎﻧﺒﻲ ﺍﺯ ﺭﻭﺵ ﻧﺎﻣﮕﺬﺍﺭﻱ‪ x.٨٠٢x :‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ X .‬ﻳﮏ ﻋﺪﺩ ﻣﻨﺼﺮ ﺑﻔﺮﺩ ﺑﻮﺩﻩ ﮐﻪ‬ ‫ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﻤﻴﺘﻪ ﻫﺎ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﻮﺩ ‪ .‬ﮔﺮﻭﻩ ‪ ٨٠٢,٣‬ﻣﺴﺌﻮﻟﻴﺖ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺳﺎﺯﻱ‬ ‫ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ CSMA/CD‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻨﺪ‪) .‬ﺷﺒﮑﻪ ﻓﻮﻕ ﺩﺭ ﺍﺑﺘﺪﺍ ‪DIX‬‬ ‫‪ Ethernet‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﺪ ( ﺍﺗﺮﻧﺖ ﻭ ‪ ٨٠٢,٣‬ﺍﺯ ﻧﻈﺮ ﻓﺮﻣﺖ ﺩﺍﺩﻩ ﻫﺎ ﺩﺭ ﻓﺮﻳﻢ ﻫﺎﻱ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺘﻔﺎﻭﺕ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺷﺒﮑﻪ‬

‫ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻣﺪﻝ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ )ﺭﻭﻳﮑﺮﺩ ﺩﻳﮕﺮﻱ ﺍﺯ ﺍﺗﺮﻧﺖ( ﺗﻮﺳﻂ‬

‫ﺷﺮﮐﺖ ‪ IBM‬ﻭ ﺑﺎ ﻧﺎﻡ ‪ ring Token‬ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺍﺯ ﻓﻮﺍﺻﻞ ﺧﺎﻟﻲ )‪ (Gap‬ﺗﺼﺎﺩﻓﻲ ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﻘﺎﻝ ﻓﺮﻳﻢ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ‪ Token ring‬ﺍﺯ ﻳﮏ ﺭﻭﺵ ﭘﻴﻮﺳﺘﻪ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺍﻳﺴﺘﮕﺎﻩ ﻫﺎ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺣﻠﻘﻪ ﻣﻨﻄﻘﻲ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ‬

‫ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻓﺮﻳﻢ ﻫﺎ ﺻﺮﻓﺎ" ﺩﺭ ﻳﮏ ﺟﻬﺖ ﺣﺮﮐﺖ ﻭ ﭘﺲ ﺍﺯ ﻃﻲ ﻃﻮﻝ ﺣﻠﻘﻪ‪ ،‬ﻓﺮﻳﻢ ﮐﻨﺎﺭ‬ ‫‪238‬‬

‫ﮔﺬﺍﺷﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺭﻭﺵ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﺎﺑﻊ‬

‫‪ CSMA/CD‬ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ ﻭ ﺍﺯ ﺭﻭﺵ ‪ passing Token‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺭﻭﺵ‬

‫ﻓﻮﻕ ﺩﺭ ﺍﺑﺘﺪﺍ ﻳﮏ ‪ ) Token‬ﻧﻮﻉ ﺧﺎﺻﻲ ﺍﺯ ﻳﮏ ﻓﺮﻳﻢ ﺍﻃﻼﻋﺎﺗﻲ ( ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫‪ Token‬ﻓﻮﻕ ﺩﺭ ﻃﻮﻝ ﺣﻠﻘﻪ ﻣﻲ ﭼﺮﺧﺪ ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﺍﻳﺴﺘﮕﺎﻩ ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺭﺍ‬

‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ‪ Token‬ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮔﺮﻓﺘﻪ ﻭ ﻓﺮﻳﻢ ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺩ ﺭﺍ ﺑﺮ ﺭﻭﻱ‬ ‫ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺍﺭﺳﺎﻝ ﺩﺍﺭﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻓﺮﻳﻢ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﻣﺠﺪﺩﺍ" ﺑﻪ ﺍﻳﺴﺘﮕﺎﻩ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ‬ ‫ﺑﺮﮔﺸﺖ ﺩﺍﺩﻩ ﺷﺪ )ﻃﻲ ﻧﻤﻮﺩﻥ ﻣﺴﻴﺮ ﺣﻠﻘﻪ(‪ ،‬ﺍﻳﺴﺘﮕﺎﻩ ﻓﺮﻳﻢ ﺧﻮﺩ ﺭﺍ ﺣﺬﻑ ﻭ ﻳﮏ ‪Token‬‬

‫ﺟﺪﻳﺪ ﺭﺍ ﺍﻳﺠﺎﺩ ﻭﺁﻥ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﺣﻠﻘﻪ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮔﺮﻓﺘﻦ ‪ Token‬ﺷﺮﻁ‬ ‫ﻻﺯﻡ ﺑﺮﺍ ﻱ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪ .‬ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﭼﻬﺎﺭ‬

‫ﺗﺎ ﺷﺎﻧﺰﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪.‬‬ ‫ﺍﺗﺮﻧﺖ ﺑﺎ ﻳﮏ ﺭﻭﻧﺪ ﭘﻴﻮﺳﺘﻪ ﻫﻤﭽﻨﺎﻥ ﺑﻪ ﺭﺷﺪ ﺧﻮﺩ ﺍﺩﺍﻣﻪ ﻣﻲ ﺩﻫﺪ‪ .‬ﭘﺲ ﺍﺯ ﮔﺬﺷﺖ‬ ‫ﺣﺪﻭﺩ ﺳﻲ ﺳﺎﻝ ﺍﺯﻋﻤﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺍﻳﺠﺎﺩ ﻭ ﺑﺮﺍﻱ ﻋﻤﻮﻡ‬ ‫ﻣﺘﺨﺼﺼﻴﻦ ﺷﻨﺎﺧﺘﻪ ﺷﺪﻩ ﻫﺴﺘﻨﺪ ﻭ ﻫﻤﻴﻦ ﺍﻣﺮ ﻧﮕﻬﺪﺍﺭﻱ ﻭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺭﺍ‬ ‫ﺁﺳﺎﻥ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺍﺗﺮﻧﺖ ﺑﺎ ﺻﻼﺑﺖ ﺑﺴﻤﺖ ﺍﻓﺰﺍﻳﺶ ﺳﺮﻋﺖ ﻭ ﺑﻬﺒﻮﺩ ﮐﺎﺭﺁﺋﻲ ﻭ ﻋﻤﻠﮑﺮﺩ‬ ‫ﮔﺎﻡ ﺑﺮﻣﻲ ﺩﺍﺭﺩ‪.‬‬

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‫‪NAT‬‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﺳﺮﻋﺘﻲ ﺑﺎﻭﺭﻧﮑﺮﺩﻧﻲ ﻫﻤﺠﻨﺎﻥ ﺩﺭ ﺣﺎﻝ ﮔﺴﺘﺮﺵ ﺍﺳﺖ‪ .‬ﺗﻌﺪﺍﺩ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬

‫ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ ) ﺧﺪﻣﺎﺕ ( ﻭ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺭﻭﺯﺍﻧﻪ ﺗﻐﻴﻴﺮ ﻭ ﺭﺷﺪ ﻣﻲ ﻳﺎﺑﺪ‪ .‬ﺑﺎ ﺍﻳﻨﮑﻪ‬ ‫ﻧﻤﻲ ﺗﻮﺍﻥ ﺩﻗﻴﻘﺎ" ﺍﻧﺪﺍﺯﻩ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﻣﺸﺨﺺ ﮐﺮﺩ ﻭﻟﻲ ﺗﻘﺮﻳﺒﺎ" ﻳﮑﺼﺪ ﻣﻴﻠﻴﻮﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻴﺰﺑﺎﻥ‬ ‫)‪ (Host‬ﻭ ‪ ٣٥٠‬ﻣﻴﻠﻴﻮﻥ ﮐﺎﺭﺑﺮ ﺍﺯ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺭﺷﺪ ﺍﻳﻨﺘﺮﻧﺖ ﭼﻪ ﻧﻮﻉ‬

‫ﺍﺭﺗﺒﺎﻃﻲ ﺑﺎ )‪ Network Address Translator (NAT‬ﺩﺍﺭﺩ؟ ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻭﺏ ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺑﺎﺷﺪ‪ IP .‬ﻳﮏ ﻋﺪﺩ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ‪ ٣٢‬ﺑﻴﺘﻲ ﺑﻮﺩﻩ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﮐﻨﺪ‪.‬‬

‫ﺍﻭﻟﻴﻦ ﻣﺮﺗﺒﻪ ﺍﻱ ﮐﻪ ﻣﺴﺌﻠﻪ ﺁﺩﺭﺱ ﺩﻫﻲ ﺗﻮﺳﻂ ‪ IP‬ﻣﻄﺮﺡ ﮔﺮﺩﻳﺪ‪ ،‬ﮐﻤﺘﺮ ﮐﺴﻲ ﺑﻪ ﺍﻳﻦ ﻓﮑﺮ‬ ‫ﻣﻲ ﺍﻓﺘﺎﺩ ﮐﻪ ﻣﻤﮑﻦ ﺍﺳﺖ ﺧﻮﺍﺳﺘﻪ ﺍﻱ ﻣﻄﺮﺡ ﺷﻮﺩ ﮐﻪ ﻧﺘﻮﺍﻥ ﺑﻪ ﺁﻥ ﻳﮏ ﺁﺩﺭﺱ ﺭﺍ ﻧﺴﺒﺖ‬ ‫ﺩﺍﺩ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻴﺴﺘﻢ ﺁﺩﺭﺱ ﺩﻫﻲ ‪ IP‬ﻣﻲ ﺗﻮﺍﻥ ‪ (٢٣٢) ٤,٢٩٤,٩٧٦,٢٩٦‬ﺁﺩﺭﺱ ﺭﺍ ﺗﻮﻟﻴﺪ‬

‫ﮐﺮﺩ‪ ) .‬ﺑﺼﻮﺭﺕ ﺗﺌﻮﺭﻱ (‪ .‬ﺗﻌﺪﺍﺩ ﻭﺍﻗﻌﻲ ﺁﺩﺭﺱ ﻫﺎﻱ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻤﺘﺮ ﺍﺯ ﻣﻘﺪﺍﺭ ) ﺑﻴﻦ ‪٣,٢‬‬

‫ﻣﻴﻠﻴﺎﺭﺩ ﻭ ‪ ٣,٣‬ﻣﻴﻠﻴﺎﺭﺩ ( ﻓﻮﻕ ﺍﺳﺖ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ‪ ،‬ﺗﻔﮑﻴﮏ ﺁﺩﺭﺱ ﻫﺎ ﺑﻪ ﮐﻼﺱ ﻫﺎ ﻭ ﺭﺯﻭ‬ ‫ﺑﻮﺩﻥ ﺑﺮﺧﻲ ﺁﺩﺭﺱ ﻫﺎ ﺑﺮﺍﻱ ‪ ، multicasting‬ﺗﺴﺖ ﻭ ﻣﻮﺍﺭﺩ ﺧﺎﺹ ﺩﻳﮕﺮ ﺍﺳﺖ‪.‬‬ ‫ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﻧﻔﺠﺎﺭ ﺍﻳﻨﺘﺮﻧﺖ ) ﻋﻤﻮﻣﻴﺖ ﻳﺎﻓﺘﻦ( ﻭ ﺍﻓﺰﺍﻳﺶ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‪ ،‬ﺗﻌﺪﺍﺩ ‪IP‬‬

‫ﻣﻮﺟﻮﺩ‪ ،‬ﭘﺎﺳﺨﮕﻮﻱ ﻧﻴﺎﺯﻫﺎ ﻧﺒﻮﺩ‪ .‬ﻣﻨﻄﻘﻲ ﺗﺮﻳﻦ ﺭﻭﺵ‪ ،‬ﻃﺮﺍﺣﻲ ﻣﺠﺪﺩ ﺳﻴﺴﺘﻢ ﺁﺩﺭﺱ ﺩﻫﻲ ‪IP‬‬ ‫ﺍﺳﺖ ﺗﺎ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺑﻴﺸﹶﺘﺮﻱ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﻣﻮﺿﻮﻉ ﻓﻮﻕ ﺩﺭ ﺣﺎﻝ‬ ‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺑﻮﺩﻩ ﻭ ﻧﺴﺨﻪ ﺷﻤﺎﺭﻩ ﺷﺶ ‪ ، IP‬ﺭﺍﻫﮑﺎﺭﻱ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺍﺳﺖ ‪ .‬ﭼﻨﺪﻳﻦ ﺳﺎﻝ‬ ‫ﻃﻮﻝ ﺧﻮﺍﻫﺪ ﮐﺸﻴﺪ ﺗﺎ ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﮔﺮﺩﺩ‪ ،‬ﭼﺮﺍﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺗﻤﺎﻣﻲ ﺯﻳﺮﺳﺎﺧﺖ‬

‫ﻫﺎﻱ ﺍﻳﻨﺘﺮﻧﺖ ﺗﻐﻴﻴﺮ ﻭﺍﺻﻼﺡ ﮔﺮﺩﻧﺪ‪ NAT.‬ﺑﺎ ﻫﺪﻑ ﮐﻤﮏ ﺑﻪ ﻣﺸﮑﻞ ﻓﻮﻕ ﻃﺮﺍﺣﻲ ﺷﺪﻩ‬ ‫ﺍﺳﺖ‪ NAT .‬ﺑﻪ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺍﺟﺎﺯﻩ ﻣﻲ ﺩﻫﺪ ﮐﻪ ﺑﺼﻮﺭﺕ ﻳﮏ ﺭﻭﺗﺮ ﻋﻤﻞ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ‬ ‫ﺣﺎﻟﺖ ‪ NAT‬ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﺁﮊﺍﻧﺲ ﺑﻴﻦ ﺍﻳﻨﺘﺮﻧﺖ ) ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ( ﻭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺤﻠﻲ‬

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‫) ﺷﺒﮑﻪ ﺧﺼﻮﺻﻲ ( ﺭﻓﺘﺎﺭ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ ﺻﺮﻓﺎ" ﻳﮏ ‪ IP‬ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﻧﻤﺎﻳﺶ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ) ﻳﮏ ﮔﺮﻭﻩ ( ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﮐﻢ ﺑﻮﺩﻥ ﺗﻌﺪﺍﺩ ‪ IP‬ﺻﺮﻓﺎ" ﻳﮑﻲ ﺍﺯ ﺩﻻﻳﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ NAT‬ﺍﺳﺖ ‪.‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﻋﻠﻞ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪NAT‬ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬ ‫ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ‪NAT‬‬ ‫ﻋﻤﻠﮑﺮﺩ ‪ NAT‬ﻣﺸﺎﺑﻪ ﻳﮏ ﺗﻠﻔﺘﭽﻲ ﺩﺭ ﻳﮏ ﺍﺩﺍﺭﻩ ﺑﺰﺭﮒ ﺍﺳﺖ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﺷﻤﺎ ﺑﻪ ﺗﻠﻔﻨﭽﻲ‬

‫ﺍﺩﺍﺭﻩ ﺧﻮﺩ ﺍﻋﻼﻡ ﻧﻤﻮﺩﻩ ﺍﻳﺪ ﮐﻪ ﺗﻤﺎﺱ ﻫﺎﻱ ﺗﻠﻔﻨﻲ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﻤﺎ ﺭﺍ ﺗﺎ ﺑﻪ ﻭﻱ ﺍﻋﻼﻡ ﻧﻨﻤﻮﺩﻩ‬

‫ﺍﻳﺪ ‪ ،‬ﻭﺻﻞ ﻧﮑﻨﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﻳﮑﻲ ﺍﺯﻣﺸﺘﺮﻳﺎﻥ ﺗﻤﺎﺱ ﮔﺮﻓﺘﻪ ﻭ ﺑﺮﺍﻱ ﻭﻱ ﭘﻴﺎﻣﻲ ﮔﺬﺍﺷﺘﻪ‬ ‫ﺍﻳﺪ ﮐﻪ ﺳﺮﻳﻌﺎ" ﺑﺎ ﺷﻤﺎ ﺗﻤﺎﺱ ﺑﮕﻴﺮﺩ‪ .‬ﺷﻤﺎ ﺑﻪ ﺗﻠﻔﺘﭽﻲ ﺍﺩﺍﺭﻩ ﻣﻲ ﮔﻮﺋﻴﺪ ﮐﻪ ﻣﻨﺘﻈﺮ ﺗﻤﺎﺱ‬

‫ﺗﻠﻔﻦ ﺍﺯ ﻃﺮﻑ ﻳﮑﻲ ﺍﺯ ﻣﺸﺘﺮﻳﺎﻥ ﻫﺴﺘﻢ‪ ،‬ﺩﺭ ﺻﻮﺭﺕ ﺗﻤﺎﺱ ﻭﻱ‪ ،‬ﺁﻥ ﺭﺍ ﺑﻪ ﺩﻓﺘﺮ ﻣﻦ ﻭﺻﻞ‬ ‫ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﺸﺘﺮﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎ ﺍﺩﺍﺭﻩ ﺷﻤﺎ ﺗﻤﺎﺱ ﮔﺮﻓﺘﻪ ﻭ ﺑﻪ ﺗﻠﻔﻨﭽﻲ ﺍﻋﻼﻡ ﻣﻲ ﻧﻤﺎﻳﺪ‬ ‫ﮐﻪ ﻗﺼﺪ ﮔﻔﺘﮕﻮ ﺑﺎ ﺷﻤﺎ ﺭﺍ ﺩﺍﺭﺩ )ﭼﺮﺍﮐﻪ ﺷﻤﺎ ﻣﻨﺘﻈﺮ ﺗﻤﺎﺱ ﻭﻱ ﻫﺴﺘﻴﺪ(‪ .‬ﺗﻠﻔﻨﭽﻲ ﺟﺪﻭﻝ‬

‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺑﺮﺭﺳﻲ ﺗﺎ ﻧﺎﻡ ﺷﻤﺎ ﺭﺍ ﺩﺭ ﺁﻥ ﭘﻴﺪﺍ ﻧﻤﺎﻳﺪ‪ .‬ﺗﻠﻔﻨﭽﻲ ﻣﺘﻮﺟﻪ ﻣﻲ ﺷﻮﺩ ﮐﻪ ﺷﻤﺎ‬ ‫ﺗﻠﻔﻦ ﻓﻮﻕ ﺭﺍ ﺩﺭﺧﻮﺍﺳﺖ ﻧﻤﻮﺩﻩ ﺍﻳﺪ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﻤﺎﺱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﺩﻓﺘﺮ ﺷﻤﺎ ﻭﺻﻞ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪.‬‬

‫‪ NAT‬ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﺳﻴﺴﮑﻮ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﻳﮏ ﺩﺳﺘﮕﺎﻩ )ﻓﺎﻳﺮﻭﺍﻝ‪ ،‬ﺭﻭﺗﺮ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫( ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪ NAT.‬ﺑﻴﻦ ﻳﮏ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﻭ ﻳﮏ ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ﻣﺴﺘﻘﺮ ﻭ ﺷﺎﻣﻞ ﻣﺪﻝ‬ ‫ﻫﺎ ﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ NAT‬ﺍﻳﺴﺘﺎ ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﺮﺟﻤﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻏﻴﺮ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ‬ ‫) ﺛﺒﺖ ﺷﺪﻩ ( ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺭﺍ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪ ) .‬ﺗﻨﺎﻇﺮ ﻳﮏ ﺑﻪ‬

‫ﻳﮏ( ﺭﻭﺵ ﻓﻮﻕ ﺯﻣﺎﻧﻴﮑﻪ ﻗﺼﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺧﺎﺭﺝ ﺍﺯ ﺷﺒﮑﻪ‬ ‫‪241‬‬

‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪ ،‬ﻣﻔﻴﺪ ﻭ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻫﻤﻮﺍﺭﻩ‬ ‫‪IP‬‬

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‫‪ 192.168.32.10‬ﺑﻪ ‪ IP 213.18.123.110‬ﺗﺮﺟﻤﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫‪ NAT‬ﭘﻮﻳﺎ ‪ .‬ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻏﻴﺮ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺭﺍ ﺑﻪ ﻳﮏ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺗﺮﺟﻤﻪ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺗﺮﺟﻤﻪ ﻓﻮﻕ ﺍﺯ ﮔﺮﻭﻫﻲ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫‪ . OverLoading‬ﻣﺪﻝ ﻓﻮﻕ ﺷﮑﻞ ﺧﺎﺻﻲ ﺍﺯ ‪ NAT‬ﭘﻮﻳﺎ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ‬

‫ﭼﻨﺪﻳﻦ ‪ IP‬ﻏﻴﺮ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺑﻪ ﻳﮏ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ‬

‫ﻣﺘﻌﺪﺩ‪ ،‬ﺗﺮﺟﻤﻪ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺑﻪ ﺭﻭﺵ ﻓﻮﻕ ‪Port Address (PAT‬‬ ‫‪ (Translation‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫‪ . Overlapping‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺷﺒﮑﻪ ﺧﺼﻮﺻﻲ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ‬ ‫ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﺪ ﮐﻪ ﺗﻮﺳﻂ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ NAT .‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﻣﻨﺤﺼﺮﺑﻔﺮﺩ ﺗﺮﺟﻤﻪ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪ NAT‬ﻫﻤﻮﺍﺭﻩ ﺁﺩﺭﺱ ﻫﺎﻱ ﻳﮏ ﺷﺒﮑﻪ ﺧﺼﻮﺻﻲ ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ‬

‫ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺗﺮﺟﻤﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ NAT .‬ﻫﻤﭽﻨﻴﻦ ﺁﺩﺭﺱ ﻫﺎﻱ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﻋﻤﻮﻣﻲ‬ ‫ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺧﺼﻮﺻﻲ ﺗﺮﺟﻤﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪) .‬ﺩﺭ ﻫﺮ‬ ‫‪242‬‬

‫ﺣﺎﻟﺖ ﺧﺮﻭﺟﻲ ‪ ، NAT‬ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ‬

‫ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻋﻤﻮﻣﻲ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺟﻬﺎﻧﻲ ﺑﺎﺷﻨﺪ ﻭ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﺧﺼﻮﺻﻲ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﻣﺤﻠﻲ ﺑﺎﺷﻨﺪ (‬

‫ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﺻﻲ ) ﺧﺼﻮﺻﻲ ( ﻣﻌﻤﻮﻻ" ﺑﺼﻮﺭﺕ ﻳﮏ ﺷﺒﮑﻪ ‪ LAN‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﮐﻪ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺩﺍﺧﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﺣﻮﺯﻩ ﻣﺤﻠﻲ‬

‫ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﺍﻏﻠﺐ ﺗﺮﺍﻓﻴﮏ ﺷﺒﮑﻪ ﺩﺭ ﺣﻮﺯﻩ ﻣﺤﻠﻲ ﺑﺼﻮﺭﺕ ﺩﺍﺧﻠﻲ ﺑﻮﺩﻩ ﻭﺑﻨﺎﺑﺮﺍﻳﻦ ﺿﺮﻭﺭﺗﻲ‬ ‫ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺧﺎﺭﺝ ﺍﺯ ﺷﺒﮑﻪ ﺭﺍ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻳﮏ ﺣﻮﺯﻩ ﻣﺤﻠﻲ ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﻱ‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﻭ ﻳﺎ ﻏﻴﺮﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺑﺎﺷﺪ‪ .‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺍﺯ ﺁﺩﺭﺱ‬ ‫ﻫﺎﻱ ‪ IP‬ﻏﻴﺮﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﻨﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ‪ NAT‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺩﻧﻴﺎﻱ‬ ‫ﺧﺎﺭﺝ ﺍﺯ ﺷﺒﮑﻪ ﻣﺤﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫‪ NAT‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﭘﻴﮑﺮﺑﻨﺪﻱ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻣﺜﺎﻝ ﺯﻳﺮ ‪NAT‬‬

‫ﺑﮕﻮﻧﻪ ﺍﻱ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﺑﺘﻮﺍﻧﺪ ﺁﺩﺭﺱ ﻫﺎﻱ ﻏﻴﺮ ﺭﻳﺠﺴﺘﺮ ﺷﺪﻩ ‪) IP‬ﺩﺍﺧﻠﻲ ﻭ‬ ‫ﻣﺤﻠﻲ( ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺧﺼﻮﺻﻲ )ﺩﺍﺧﻠﻲ( ﻣﻲ ﺑﺎﺷﻨﺪ ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭﻳﺠﺴﺘﺮ‬ ‫ﺷﺪﻩ ﺗﺮﺟﻤﻪ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫ﻳﮏ ‪) ISP‬ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ( ﻳﮏ ﻣﺤﺪﻭﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭﺍ‬

‫ﺑﺮﺍﻱ ﺷﺮﮐﺖ ﺷﻤﺎ ﺩﺭ ﻧﻈﺮ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ﺭﻳﺠﺴﺘﺮ ﻭ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ‬ ‫ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ ‪ Inside global‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ‬ ‫‪ IP‬ﺧﺼﻮﺻﻲ ﻭ ﻏﻴﺮﺭﻳﭽﺴﺘﺮ ﺷﺪﻩ ﺑﻪ ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﻧﺪ‪ :‬ﻳﮏ ﮔﺮﻭﻩ‬

‫ﮐﻮﭼﮏ ﮐﻪ ﺗﻮﺳﻂ ‪ NAT‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ )‪ (Outside local address‬ﻭ ﮔﺮﻭﻩ‬

‫ﺑﺰﺭﮔﺘﺮﻱ ﮐﻪ ﺗﻮﺳﻂ ﺣﻮﺯﻩ ﻣﺤﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﻨﺪ ﺷﺪ) ‪.(Inside local dress‬‬ ‫ﺁﺩﺭﺱ ﻫﺎﻱ ‪ Outside local‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺮﺟﻤﻪ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨﺤﺼﺮﺑﻔﺮﺩ ‪IP‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨـﺤﺼﺮ ﺑﻔﺮﺩ ﻓﻮﻕ‪ outside global ،‬ﻧﺎﻣﻴﺪﻩ‬ ‫ﺷﺪﻩ ﻭ ﺍﺧﺘﺼﺎﺹ ﺑﻪ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ) ﺍﻳﻨﺘﺮﻧﺖ( ﺩﺍﺭﻧﺪ‪.‬‬

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‫ﺍﮐﺜﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ﺩﺍﺧﻠﻲ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪inside‬‬ ‫‪ local‬ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺑﺮﺧﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ﺩﺍﺧﻠﻲ ﮐﻪ ﻧﻴﺎﺯﻣﻨﺪ ﺍﺭﺗﺒﺎﻁ ﺩﺍﺋﻢ ﺑﺎ ﺧﺎﺭﺝ ﺍﺯ‬ ‫ﺷﺒﮑﻪ ﺑﺎﺷﻨﺪ ‪،‬ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ inside global‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻧﻴﺎﺯﻱ ﺑﻪ‬ ‫ﺗﺮﺟﻤﻪ ﻧﺨﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ﻣﺤﻠﻲ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ‪inside local‬‬ ‫ﺍﺳﺖ‪ ،‬ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺧﺎﺭﺝ ﺷﺒﮑﻪ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻭﻱ ﺩﺭ‬ ‫ﺍﺧﺘﻴﺎﺭ ‪ NAT‬ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪.‬‬

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‫‪ NAT‬ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺧﻮﺩ ﺭﺍ ﺑﺮﺭﺳﻲ ﺗﺎ ﺑﻪ ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺑﺮﺳﺪ ﮐﻪ ﺑﺮﺍﻱ ﺁﺩﺭﺱ‬ ‫ﻣﻘﺼﺪ ﻳﮏ ‪ entry‬ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺩﺍﺭﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﺎﺳﺦ ﻣﺜﺒﺖ ﺑﺎﺷﺪ‪ NAT ،‬ﺑﺴﺘﻪ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺗﺮﺟﻤﻪ ﻭ ﻳﮏ ‪ entry‬ﺑﺮﺍﻱ ﺁﻥ ﺍﻳﺠﺎﺩ ﻭ ﺁﻥ ﺭﺍ ﺩﺭ ﺟﺪﻭﻝ‬ ‫ﺗﺮﺟﻤﻪ ﺁﺩﺭﺱ )‪ (ATT‬ﺛﺒﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﺎﺳﺦ ﻣﻨﻔﻲ ﺑﺎﺷﺪ ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺩﻭﺭ ﺍﻧﺪﺍﺧﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺁﺩﺭﺱ ‪ ، inside global‬ﺭﻭﺗﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ‬ ‫ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ) ﺍﻳﻨﺘﺮﻧﺖ (‪ ،‬ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﺷﺒﮑﻪ‬

‫ﺧﺼﻮﺻﻲ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﺁﺩﺭﺱ ﻣﺒﺪﺍﺀ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ‪outside global‬‬ ‫ﺍﺳﺖ ‪ .‬ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﻳﮏ ﺁﺩﺭﺱ ‪ inside global‬ﺍﺳﺖ‪.‬‬

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‫‪ NAT‬ﺩﺭ ﺟﺪﻭﻝ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﺧﻮﺩ ﺟﺴﺘﺠﻮ ﻭ ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﺭﺍ ﺗﺸﺨﻴﺺ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ‬

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‫‪ NAT‬ﺁﺩﺭﺱ ﻫﺎﻱ ‪ inside global‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪inside‬‬

‫ﺁﻥ ﺭﺍ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ﺩﺍﺧﻠﻲ ﻧﺴﺒﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫‪ local‬ﺗﺮﺟﻤﻪ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫‪VLAN‬‬ ‫) ‪ ،VLAN ( Virtual Local Area Networks‬ﻳـﮑﻲ ﺍﺯ ﺟﺪﻳﺪﺗــﺮﻳﻦ ﻭ‬

‫ﺟﺎﻟﺒﺘﺮﻳﻦ ﺗﮑﻨﻮﻟــﻮﮊﻱ ﻫﺎﻱ ﺷﺒﮑﻪ ﺍﺳﺖ ﮐﻪ ﺍﺧـﻴﺮﺍ" ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﺑﻴﺸﺘﺮﻱ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺍﺳﺖ‪.‬‬ ‫ﺭﺷﺪ ﺑﺪﻭﻥ ﻭﻗﻔﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﻭ ﺿﺮﻭﺭﺕ ﮐﺎﻫﺶ ﻫﺰﻳﻨﻪ ﻫﺎ ﺑﺮﺍﻱ ﺗﺠﻬﻴﺰﺍﺕ ﮔﺮﺍﻧﻘﻴﻤﺖ‬ ‫ﺑﺪﻭﻥ ﺍﺯ ﺩﺳﺖ ﺩﺍﺩﻥ ﮐﺎﺭﺁﺋﻲ ﻭ ﺍﻣﻨﻴﺖ‪ ،‬ﺍﻫﻤﻴﺖ ﻭ ﺿﺮﻭﺭﺕ ﺗﻮﺟﻪ ﺑﻴﺸﺘﺮ ﺑﻪ ‪ VLAN‬ﺭﺍ‬

‫ﻣﻀﺎﻋﻒ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪.‬‬

‫ﻭﺿﻌﻴﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻌﻠﻲ‬

‫ﺗﻘﺮﻳﺒﺎ" ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎ ﺍﻣﺮﻭﺯﻱ ﺍﺯ ﻳﮏ )ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ( ﺳﻮﺋﻴﭻ ﮐﻪ ﺗﻤﺎﻣﻲ ﮔﺮﻩ ﻫﺎﻱ‬

‫ﺷﺒﮑﻪ ﺑﻪ ﺁﻥ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ ‪ ،‬ﺍﺳﺘﻔﺎﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎ ﺭﻭﺷﻲ ﻣﻄﻤﺌﻦ ﻭ ﺳﺮﻳﻊ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﮔﺮﻩ ﻫﺎ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬ﺑﺎ ﺍﻳﻦ ﮐﻪ ﺳﻮﺋﻴﭻ ﻫﺎ‬

‫ﺑﺮﺍﻱ ﺍﻧﻮﺍﻉ ﺷﺒﮑﻪ ﻫﺎ‪ ،‬ﮔﺰﻳﻨﻪ ﺍﻱ ﻣﻨﺎﺳﺐ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻭﻟﻲ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﺷﺪ ﺷﺒﮑﻪ ﻭ ﺍﻓﺰﺍﻳﺶ‬ ‫ﺗﻌﺪﺍﺩ ﺍﻳﺴﺘﮕﺎﻫﻬﺎ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‪ ،‬ﺷﺎﻫﺪ ﺑﺮﻭﺯ ﻣﺴﺎﺋﻞ ﺧﺎﺻﻲ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎ‪،‬‬ ‫ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻻﻳﻪ ﺩﻭﻡ )ﻣﺪﻝ ﻣﺮﺟﻊ ‪ ( OSI‬ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﻳﮏ ﺷﺒﮑﻪ ‪ Flat‬ﺭﺍ ﺍﻳﺠﺎﺩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺑﻪ ﻳﮏ ﺳﻮﺋﻴﭻ‪ ،‬ﺳﻪ ﺍﻳﺴﺘﮕﺎﻩ ﻣﺘﺼﻞ ﺷﺪﻩ‬ ‫ﺍﺳﺖ‪ .‬ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻓﻮﻕ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺑﻮﺩﻩ ﻭ ﻫﺮ ﻳﮏ ﺑﻪ ﻋﻨﻮﺍﻥ ﻋﻀﻮﻱ ﺍﺯ‬

‫ﻳﮏ ‪ Broadcast domain‬ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻳﺴﺘﮕﺎﻫﻲ‬

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‫ﻳﮏ ﭘﻴﺎﻡ ‪ broadcast‬ﺭﺍ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﺎﻳﺮ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﺳﻮﺋﻴﭻ ﻧﻴﺰ ﺁﻥ ﺭﺍ‬ ‫ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﮐﻮﭼﮏ‪ ،‬ﻭﺟﻮﺩ ﭘﻴﺎﻡ ﻫﺎﻱ ‪ Broadcast‬ﻧﻤﻲ ﺗﻮﺍﻧﺪ ﻣﺸﮑﻞ ﻭ ﻳﺎ ﻣﺴﺌﻠﻪ ﻗﺎﺑﻞ‬ ‫ﺗﻮﺟﻬﻲ ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﺎﻳﺪ‪ ،‬ﻭﻟﻲ ﺩﺭ ﺻﻮﺭﺕ ﺭﺷﺪ ﺷﺒﮑﻪ‪ ،‬ﻭﺟﻮﺩ ﭘﻴﺎﻡ ﻫﺎﻱ ‪braodcast‬‬

‫ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﻳﮏ ﻣﺸﮑﻞ ﺍﺳﺎﺳﻲ ﻭ ﻣﻬﻢ ﺗﺒﺪﻳﻞ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻭ ﺩﺭ ﺍﻏﻠﺐ ﻣﻮﺍﻗﻊ‪،‬‬ ‫ﺳﻴﻼﺑﻲ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺑﻲ ﺍﺭﺯﺵ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺩﺭ ﺣﺎﻝ ﺟﺎﺑﺠﺎﺋﻲ ﺑﻮﺩﻩ ﻭ ﻋﻤﻼ" ﺍﺯ ﭘﻬﻨﺎﻱ‬ ‫ﺑﺎﻧﺪ ﺷﺒﮑﻪ‪،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻄﻠﻮﺏ ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺗﻤﺎﻣﻲ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻳﮏ ﺳﻮﺋﻴﭻ‪،‬‬

‫ﭘﻴﺎﻡ ﻫﺎﻱ ‪ Braodcast‬ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﭼﺮﺍﮐﻪ ﺗﻤﺎﻣﻲ ﺁﻧﺎﻥ ﺑﺨﺸﻲ ﺍﺯ ﻳﮏ‬ ‫‪ Broadcast doamin‬ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺕ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﺳﻮﺋﻴﭻ ﻫﺎ ﻭ ﺍﻳﺴﺘﮕﺎﻫﻬﺎ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‪ ،‬ﻣﺸﮑﻞ ﺍﺷﺎﺭﻩ ﺷﺪﻩ‬ ‫ﻣﻠﻤﻮﺱ ﺗﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ‪.‬ﻫﻤﻮﺍﺭﻩ ﺍﺣﺘﻤﺎﻝ ﻭﺟﻮﺩ ﭘﻴﺎﻡ ﻫﺎﻱ ‪ Braodcast‬ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻣﺴﺎﺋﻞ ﻣﻬﻢ‪ ،‬ﻣﻮﺿﻮﻉ ﺍﻣﻨﻴﺖ ﺍﺳﺖ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ‬ ‫ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ ﻣﺸﺎﻫﺪﻩ ﺗﻤﺎﻣﻲ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ‬

‫ﺷﺒﮑﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﺍﻱ ﺑﺰﺭﮒ ﮐﻪ ﺩﺍﺭﺍﻱ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ ﻓﺎﻳﻞ‪ ،‬ﺑﺎﻧﮏ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﺳﺎﻳﺮ ﺍﻃﻼﻋﺎﺕ ﺣﺴﺎﺱ ﻭ ﺣﻴﺎﺗﻲ ﺍﺳﺖ ‪ ،‬ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﻣﻲ ﺗﻮﺍﻧﺪ ﺍﻣﮑﺎﻥ ﻣﺸﺎﻫﺪﻩ‬ ‫ﺗﻤﺎﻣﻲ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺭﺍ ﺑﺮﺍﻱ ﻫﺮ ﺷﺨﺺ ﻓﺮﺍﻫﻢ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻣﻨﺎﺑﻊ‬

‫ﻓﻮﻕ ﺩﺭ ﻣﻌﺮﺽ ﺗﻬﺪﻳﺪ ﻭ ﺣﻤﻼﺕ ﺑﻴﺸﺘﺮﻱ ﻗﺮﺍﺭ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻔﺎﻇﺖ ﺍﻳﻨﭽﻨﻴﻦ‬ ‫ﺳﻴﺴﺘﻢ ﻫﺎﺋﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺤﺪﻭﺩﻳﺖ ﺩﺳﺘﻴﺎﺑﻲ ﺭﺍ ﺩﺭ ﺳﻄﺢ ﺷﺒﮑﻪ ﻭ ﺑﺎ ﺍﻳﺠﺎﺩ ﺳﮕﻤﻨﺖ ﻫﺎﻱ‬ ‫ﻣﺘﻌﺪﺩ ﻭ ﻳﺎ ﺍﺳﺘﻘﺮﺍﺭ ﻳﮏ ﻓﺎﻳﺮﻭﺍﻝ ﺩﺭ ﺟﻠﻮﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺣﻴﺎﺗﻲ‪ ،‬ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪.‬‬ ‫ﻣﻌﺮﻓﻲ ‪VLAN‬‬

‫ﺗﻤﺎﻣﻲ ﻣﺴﺎﺋﻞ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺩﺭ ﺑﺨﺶ ﻗﺒﻞ ﺭﺍ ﻭ ﺗﻌﺪﺍﺩ ﺑﻴﺸﺘﺮﻱ ﺭﺍ ﮐﻪ ﺑﻪ ﺁﻧﺎﻥ ﺍﺷﺎﺭﻩ‬

‫ﻧﺸﺪﻩ ﺍﺳﺖ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﻳﺠﺎﺩ ﻳﮏ ‪ VLAN‬ﺑﻪ ﻓﺮﺍﻣﻮﺷﻲ ﺳﭙﺮﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ‪،VLAN‬‬ ‫‪247‬‬

‫ﺑﻪ ﻳﮏ ﺳﻮﺋﻴﭻ ﻻﻳﻪ ﺩﻭﻡ ﮐﻪ ﺍﻳﻦ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺭﺍ ﺣﻤﺎﻳﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺗﻌﺪﺍﺩﻱ ﺯﻳﺎﺩﻱ‬ ‫ﺍﺯ ﺍﻓﺮﺍﺩﻳﮑﻪ ﺟﺪﻳﺪﺍ" ﺑﺎ ﺩﻧﻴﺎﻱ ﺷﺒﮑﻪ ﺁﺷﻨﺎ ﺷﺪﻩ ﺍﻧﺪ ‪ ،‬ﺍﻏﻠﺐ ﺩﺍﺭﺍﻱ ﺑﺮﺩﺍﺷﺖ ﻣﻨﺎﺳﺒﻲ ﺩﺭ ﺍﻳﻦ‬ ‫ﺧﺼﻮﺹ ﻧﻤﻲ ﺑﺎﺷﻨﺪ ﻭ ﺍﻳﻨﮕﻮﻧﻪ ﺍﺳﺘﻨﺒﺎﻁ ﻧﻤﻮﺩﻩ ﺍﻧﺪ ﮐﻪ ﺻﺮﻓﺎ" ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﻌﺎﻝ‬ ‫ﻧﻤﻮﺩﻥ ‪ ، VLAN‬ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺍﺿﺎﻓﻪ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﻧﺼﺐ‬

‫ﻧﻤﺎﻳﻨﺪ‪ ) .‬ﺑﺮﺩﺍﺷﺘﻲ ﮐﺎﻣﻼ" ﺍﺷﺘﺒﺎﻩ ! (‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ، VLAN‬ﻣﻴﻠﻴﻮﻥ ﻫﺎ‬

‫ﻣﺤﺎﺳﺒﺎﺕ ﺭﻳﺎﺿﻲ ﺍﻧﺠﺎﻡ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺧﺎﺻﻲ ﮐﻪ ﺩﺭﻭﻥ ﺳﻮﺋﻴﭻ‬ ‫ﺗﻌﺒﻴﻪ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ )ﺩﻗﺖ ﺩﺭ ﺯﻣﺎﻥ ﺗﻬﻴﻪ ﻳﮏ ﺳﻮﺋﻴﭻ(‪،‬ﺩﺭ ﻏﻴﺮ ﺍﻳﻨﺼﻮﺭﺕ ﺍﻣﮑﺎﻥ‬ ‫ﺍﻳﺠﺎﺩ ﻳﮏ ‪ VLAN‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ ﺗﻬﻴﻪ ﺷﺪﻩ‪ ،‬ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﻫﺮ ‪ VLAN‬ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺳﻮﺋﻴﭻ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺑﻪ ﻣﻨﺰﻟﻪ ﻳﮏ ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﻣﻲ ﺑﺎﺷﺪ ‪ .‬ﺑﺪﻳﻦ‬ ‫ﺗﺮﺗﻴﺐ ﺑﺮﺍﻱ ﻫﺮ ‪ VLAN‬ﻣﻮﺟﻮﺩ ﻳﮏ ‪ broadcast domain‬ﺟﺪﺍﮔﺎﻧﻪ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‬ ‫‪ .‬ﭘﻴﺎﻡ ﻫﺎﻱ ‪ ، broadcast‬ﺑﻪ ﺻﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ‪ ،‬ﺍﺯ ﺭﻭﻱ ﺗﻤﺎﻣﻲ ﭘﻮﺭﺕ ﻫﺎﺋﻲ ﺍﺯ ﺷﺒﮑﻪ‬ ‫ﮐﻪ ﻋﻀﻮﻱ ﺍﺯ ﻳﮏ ‪ VLAN‬ﻣﺸﺎﺑﻪ ﻧﻤﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻓﻴﻠﺘﺮ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ‪ ،‬ﻳﮑﻲ ﺍﺯ‬ ‫ﻣﻬﻤﺘﺮﻳﻦ ﺩﻻﻳﻞ ﻣﺘﺪﺍﻭﻝ ﺷﺪﻥ ‪ VALN‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺰﺭﮒ ﺍﻣﺮﻭﺯﻱ ﺍﺳﺖ ) ﺗﻤﺎﻳﺰ ﺑﻴﻦ‬ ‫ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﺷﺒﮑﻪ (‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻳﮏ ﻧﻤﻮﻧﻪ ﺷﺒﮑﻪ ﺑﺎ ﺩﻭ ‪ VLAN‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ‪ ،‬ﻳﮏ ﺷﺒﮑﻪ ﮐﻮﭼﮏ ﺑﺎ ﺷﺶ ﺍﻳﺴﺘﮕﺎﻩ ﺭﺍ ﮐﻪ ﺑﻪ ﻳﮏ ﺳﻮﺋﻴﭻ ) ﺑﺎ ﻗﺎﺑﻠﻴﺖ‬ ‫ﺣﻤﺎﻳﺖ ﺍﺯ ‪ ( VLAN‬ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﻧﺪ‪ ،‬ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺘﺎﻧﺴﻴﻞ ‪VLAN‬‬ ‫ﺳﻮﺋﻴﭻ‪ ،‬ﺩﻭ ‪ VLAN‬ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﻫﺮ ﻳﮏ ﺳﻪ ﺍﻳﺴﺘﮕﺎﻩ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ‬ ‫)‪ VLAN1‬ﻭ ‪. (VLAN2‬‬

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‫ﺯﻣﺎﻧﻲ ﮐﻪ ﺍﻳﺴﺘﮕﺎﻩ ﺷﻤﺎﺭﻩ ﻳﮏ ﻣﺘﻌﻠﻖ ﺑﻪ ‪ ، VLAN1‬ﻳﮏ ﭘﻴﺎﻡ ‪ Braodcast‬ﺭﺍ‬

‫ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ )ﻧﻈﻴﺮ‪ ،( FF:FF:FF:FF:FF:FF:‬ﺳﻮﺋﻴﭻ ﻣﻮﺟﻮﺩ ﺁﻥ ﺭﺍ ﺻﺮﻓﺎ" ﺑﺮﺍﻱ‬ ‫ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﺷﻤﺎﺭﻩ ﺩﻭ ﻭﺳﻪ ﻓﻮﺭﻭﺍﺭﺩ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺳﺎﻳﺮ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ‬ ‫ﻣﺘﻌﻠﻖ ﺑﻪ ‪ ، VLAN2‬ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﭘﻴﺎﻡ ﻫﺎﻱ ‪ broadcast‬ﺍﺭﺳﺎﻟﻲ ﺑﺮ ﺭﻭﻱ‬ ‫‪ VLAN1‬ﺭﺍ ﭘﻴﺪﺍ ﻧﮑﺮﺩﻩ ﻭ ﺩﺭﮔﻴﺮ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﻧﺨﻮﺍﻫﻨﺪ‬

‫ﺷﺪ‪.‬‬ ‫ﺩﺭ ﺣﻘﻴﻘﺖ ‪ ،‬ﺳﻮﺋﻴﭽﻲ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﺎﻳﺖ ﺍﺯ ‪ VLAN‬ﻣﻲ ﺑﺎﺷﺪ ‪ ،‬ﺍﻣﮑﺎﻥ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﭼﻨﺪﻳﻦ‬

‫ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﻣﺸﺎﺑﻪ ﺩﺍﺷﺘﻦ ﺩﻭ ﺳﻮﺋﻴﭻ ﺟﺪﺍﮔﺎﻧﻪ ﻭ ﺍﺗﺼﺎﻝ ﺳﻪ ﺍﻳﺴﺘﮕﺎﻩ ﺑﻪ‬ ‫ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ ﺩﺭ ﻣﻘﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ .( VLAN‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺷﺎﻫﺪ ﮐﺎﻫﺶ ﭼﺸﻤﮕﻴﺮ ﻫﺰﻳﻨﻪ‬ ‫ﻫﺎﻱ ﺑﺮﭘﺎﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ‪.‬‬ ‫ﻓﺮﺽ ﮐﻨﻴﺪ ﻗﺼﺪ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ﺯﻳﺮ ﺳﺎﺧﺖ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﺰﺭﮒ ﺭﺍ ﺑﻪ‬ ‫ﺩﻭﺍﺯﺩﻩ ﺷﺒﮑﻪ ﺟﺪﺍﮔﺎﻧﻪ ﺗﻘﺴﻴﻢ ﻧﻤﺎﺋﻴﻢ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺗﻬﻴﻪ ﺩﻭﺍﺯﺩﻩ ﺳﻮﺋﻴﭻ ﻭ ﺍﺗﺼﺎﻝ‬ ‫ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ ‪ ،‬ﺩﻭﺍﺯﺩﻩ ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺁﻧﺎﻥ‬ ‫ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﺎﺋﻴﻢ‪ .‬ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﺗﺎﻣﻴﻦ ﺧﻮﺍﺳﺘﻪ ﻓﻮﻕ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫‪ VLAN‬ﺍﺳﺖ ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﮏ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﺳﻮﺋﻴﭻ ﮐﻪ ‪ VLAN‬ﺭﺍ ﺣﻤﺎﻳﺖ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺩﻭﺍﺯﺩﻩ ‪ VLAN‬ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩ ‪ .‬ﺑﺪﻳﻬﻲ ﺍﺳﺖ‪ ،‬ﻫﺰﻳﻨﻪ ﺑﺮﭘﺎﺳﺎﺯﻱ ﭼﻨﻴﻦ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﻪ ﻣﺮﺍﺗﺐ ﮐﻤﺘﺮ ﺍﺯ ﺣﺎﻟﺘﻲ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺩﻭﺍﺯﺩﻩ ﺳﻮﺋﻴﭻ ﺟﺪﺍﮔﺎﻧﻪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﺷﺪﻩ ﺑﺎﺷﺪ ‪.‬‬

‫ﺩﺭ ﺯﻣﺎﻥ ﺍﻳﺠﺎﺩ ‪ ،VALN‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺗﻤﺎﻣﻲ ﺍﻳﺴﺘﮕﺎﻫﻬﺎ ﺭﺍ ﺑﻪ ﺳﻮﺋﻴﭻ ﻣﺘﺼﻞ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ‪،‬‬ ‫ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ﻫﺮ ‪ VLAN‬ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﻮﺩ‪ .‬ﻫﺮ ﺳﻮﺋﻴﭻ ﺩﺭ ﺻﻮﺭﺕ ﺣﻤﺎﻳﺖ ﺍﺯ‬ ‫‪ ، VLAN‬ﻗﺎﺩﺭ ﺑﻪ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺍﺯ ﺗﻌﺪﺍﺩ ﻣﺸﺨﺼﻲ ‪ VLAN‬ﺍﺳﺖ ‪ .‬ﻣﺜﻼ" ﻳﮏ ﺳﻮﺋﻴﭻ ﻣﻤﮑﻦ‬ ‫ﺍﺳﺖ ‪ ٦٤‬ﻭ ﻳﺎ ‪ VLAN ٢٦٦‬ﺭﺍ ﺣﻤﺎﻳﺖ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪VPN‬‬ ‫ﺩﺭ ﻃﻲ ﺩﻩ ﺳﺎﻝ ﮔﺬﺷﺘﻪ ﺩﻧﻴﺎ ﺩﺳﺘﺨﻮﺵ ﺗﺤﻮﻻﺕ ﻓﺮﺍﻭﺍﻧﻲ ﺩﺭ ﻋﺮﺻﻪ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺑﻮﺩﻩ‬

‫ﺍﺳﺖ‪ .‬ﺍﻏﻠﺐ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﮐﺎﻻ ﻭ ﺧﺪﻣﺎﺕ ﮐﻪ ﺩﺭ ﮔﺬﺷﺘﻪ ﺑﺴﻴﺎﺭ ﻣﺤﺪﻭﺩ‬ ‫ﻭ ﻣﻨﻄﻘﻪ ﺍﻱ ﻣﺴﺎﺋﻞ ﺭﺍ ﺩﻧﺒﺎﻝ ﻭ ﺩﺭ ﺻﺪﺩ ﺍﺭﺍﺋﻪ ﺭﺍﻫﮑﺎﺭﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺑﻮﺩﻧﺪ‪ ،‬ﺍﻣﺮﻭﺯﻩ ﺑﻴﺶ ﺍﺯ‬ ‫ﮔﺬﺷﺘﻪ ﻧﻴﺎﺯﻣﻨﺪ ﺗﻔﮑﺮ ﺩﺭ ﻣﺤﺪﻭﺩﻩ ﺟﻬﺎﻧﻲ ﺑﺮﺍﻱ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﻭ ﮐﺎﻻﻱ ﺗﻮﻟﻴﺪﻩ ﺷﺪﻩ ﺭﺍ ﺩﺍﺭﻧﺪ‪.‬‬

‫ﺑﻪ ﻋﺒﺎﺭﺕ ﺩﻳﮕﺮ ﺗﻔﮑﺮﺍﺕ ﻣﻨﻄﻘﻪ ﺍﻱ ﻭ ﻣﺤﻠﻲ ﺣﺎﮐﻢ ﺑﺮ ﻓﻌﺎﻟﻴﺖ ﻫﺎﻱ ﺗﺠﺎﺭﻱ ﺟﺎﻱ ﺧﻮﺩ ﺭﺍ‬ ‫ﺑﻪ ﺗﻔﮑﺮﺍﺕ ﺟﻬﺎﻧﻲ ﻭ ﺳﺮﺍﺳﺮﻱ ﺩﺍﺩﻩ ﺍﻧﺪ‪ .‬ﺍﻣﺮﻭﺯﻩ ﺑﺎ ﺳﺎﺯﻣﺎﻧﻬﺎﻱ ﺯﻳﺎﺩﻱ ﺑﺮﺧﻮﺭﺩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‬ ‫ﮐﻪ ﺩﺭ ﺳﻄﺢ ﻳﮏ ﮐﺸﻮﺭ ﺩﺍﺭﺍﻱ ﺩﻓﺎﺗﺮ ﻓﻌﺎﻝ ﻭ ﺣﺘﻲ ﺩﺭ ﺳﻄﺢ ﺩﻧﻴﺎ ﺩﺍﺭﺍﻱ ﺩﻓﺎﺗﺮ ﻣﺘﻔﺎﻭﺗﻲ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺗﻤﺎﻡ ﺳﺎﺯﻣﺎﻧﻬﺎﻱ ﻓﻮﻕ ﻗﺒﻞ ﺍﺯ ﻫﺮ ﭼﻴﺰ ﺑﺪﻧﺒﺎﻝ ﻳﮏ ﺍﺻﻞ ﺑﺴﻴﺎﺭ ﻣﻬﻢ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫ﻳﮏ ﺭﻭﺵ ﺳﺮﻳﻊ‪ ،‬ﺍﻳﻤﻦ ﻭ ﻗﺎﺑﻞ ﺍﻋﺘﻤﺎﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺩﻓﺎﺗﺮ ﻭ ﻧﻤﺎﻳﻨﺪﮔﻲ ﺩﺭ‬ ‫ﺍﻗﺼﻲ‬

‫ﻧﻘﺎﻁ ﻳﮏ ﮐﺸﻮﺭ ﻭ ﻳﺎ ﺩﺭ ﺳﻄﺢ ﺩﻧﻴﺎ‪.‬‬ ‫ﺍﮐﺜﺮ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ‪ WAN‬ﺍﺯ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ‬ ‫)‪ (Leased Line‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬ﺧﻄﻮﻁ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﺍﻧﻮﺍﻉ ﻣﺘﻔﺎﻭﺗﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪ ) ISDN‬ﺑﺎ ﺳﺮﻋﺖ ‪ ١٢٨‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ (‪(Optical Carrier-3 OC3 ) ،‬‬

‫) ﺑﺎ ﺳﺮﻋﺖ ‪ ١٥٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ﺩﺍﻣﻨﻪ ﻭﺳﻴﻊ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪ .‬ﻳﮏ‬

‫ﺷﺒﮑﻪ ‪ WAN‬ﺩﺍﺭﺍﻱ ﻣﺰﺍﻳﺎﻱ ﻋﻤﺪﻩ ﺍﻱ ﻧﺴﺒﺖ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﺑﻌﺪ‬ ‫ﺍﻣﻨﻴﺖ ﻭﮐﺎﺭﺁﺋﻲ ﺍﺳﺖ‪ .‬ﭘﺸﺘﻴﺎﻧﻲ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﻳﮏ ﺷﺒﮑﻪ ‪ WAN‬ﺩﺭ ﻋﻤﻞ ﻭ ﺯﻣﺎﻧﻴﮑﻪ ﺍﺯﺧﻄﻮﻁ‬

‫ﺍﺧﺘﺼﺎﺻﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻣﺴﺘﻠﺰﻡ ﺻﺮﻑ ﻫﺰﻳﻨﻪ ﺑﺎﻻﺋﻲ ﺍﺳﺖ‪.‬‬

‫ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﻋﻤﻮﻣﻴﺖ ﻳﺎﻓﺘﻦ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﻏﻠﺐ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺿﺮﻭﺭﺕ ﺗﻮﺳﻌﻪ ﺷﺒﮑﻪ‬ ‫ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﺭﺍ ﺑﺪﺭﺳﺘﻲ ﺍﺣﺴﺎﺱ ﮐﺮﺩﻧﺪ‪ .‬ﺩﺭ ﺍﺑﺘﺪﺍ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﻳﻨﺘﺮﺍﻧﺖ ﻣﻄﺮﺡ‬ ‫ﮔﺮﺩﻳﺪﻧﺪ‪.‬ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﺑﺼﻮﺭﺕ ﮐﺎﻣﻼ" ﺍﺧﺘﺼﺎﺻﻲ ﺑﻮﺩﻩ ﻭ ﮐﺎﺭﻣﻨﺪﺍﻥ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﺭﻣﺰ ﻋﺒﻮﺭ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﻭﺭﻭﺩ ﺑﻪ ﺷﺒﮑﻪ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺍﺧﻴﺮﺍ"‪ ،‬ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﺯ ﻣﻮﺳﺴﺎﺕ ﻭ ﺳﺎﺯﻣﺎﻧﻬﺎ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﻄﺮﺡ ﺷﺪﻥ ﺧﻮﺍﺳﺘﻪ ﻫﺎﻱ ﺟﺪﻳﺪ‬ ‫) ﮐﺎﺭﻣﻨﺪﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ‪ ،‬ﺍﺩﺍﺭﺍﺕ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ (‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﻳﺠﺎﺩ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺧﺘﺼﺎﺻﻲ ﻣﺠﺎﺯﻱ‬

‫‪ ( Virtual Private Network (VPN‬ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪.‬‬ ‫ﻳﮏ ‪ ، VPN‬ﺷﺒﮑﻪ ﺍﻱ ﺍﺧﺘﺼﺎﺻﻲ ﺑﻮﺩﻩ ﮐﻪ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﻋﻤﻮﻣﻲ ) ﻋﻤﻮﻣﺎ" ﺍﻳﻨﺘﺮﻧﺖ (‪ ،‬ﺑﺮﺍﻱ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺖ ﻫﺎﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﻭ ﺍﺭﺗﺒﺎﻁ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎﻳﮑﺪﻳﮕﺮ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﺷﺒﮑﻪ ﻫﺎ ﺩﺭ ﻋﻮﺽ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﻭﺍﻗﻌﻲ ﻧﻈﻴﺮ‪ :‬ﺧﻄﻮﻁ ‪ ،Leased‬ﺍﺯ ﻳﮏ ﺍﺭﺗﺒﺎﻁ‬

‫ﻣﺠﺎﺯﻱ ﺑﮑﻤﮏ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﻪ ﺳﺎﻳﺖ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮐﻨﺪ‪.‬‬

‫ﻋﻨﺎﺻﺮ ﺗﺸﮑﻴﻞ ﺩﻫﻨﺪﻩ ﻳﮏ ‪VPN‬‬

‫ﺩﻭ ﻧﻮﻉ ﻋﻤﺪﻩ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪:‬‬ ‫•‬

‫ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ )‪ . (Remote-Access‬ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ‬ ‫‪ ،(network Virtual private dial-up(VPDN‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪.‬ﺩﺭ‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺍﺯ ﻣﺪﻝ ﺍﺭﺗﺒﺎﻃﻲ ‪ ) User-To-Lan‬ﺍﺭﺗﺒﺎﻁ ﮐﺎﺭﺑﺮ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﻣﺤﻠﻲ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﺎﺯﻣﺎﻧﻬﺎﺋﻲ ﮐﻪ ﺍﺯ ﻣﺪﻝ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ ،‬ﺑﺪﻧﺒﺎﻝ‬ ‫ﺍﻳﺠﺎﺩ ﺗﺴﻬﻴﻼﺕ ﻻﺯﻡ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﭘﺮﺳﻨﻞ )ﻋﻤﻮﻣﺎ" ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﻭ ﺩﺭ ﻫﺮ‬

‫ﻣﮑﺎﻧﻲ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺣﻀﻮﺭ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ( ﺑﻪ ﺷﺒﮑﻪ ﺳﺎﺯﻣﺎﻥ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺳﺎﺯﻣﺎﻧﻬﺎﺋﻲ‬ ‫ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺑﺮﭘﺎﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﺑﺰﺭﮒ " ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ " ﻣﻲ ﺑﺎﺷﻨﺪ‪،‬‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻳﮏ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺟﻬﺎﻧﻲ‬

‫‪ (service provider Enterprise(ESP‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬ ‫‪ ، ESP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺼﺐ ﻭ ﭘﻴﮑﺮﺑﻨﺪﻱ ‪ ، VPN‬ﻳﮏ ‪Network access (NAS‬‬ ‫‪ (server‬ﺭﺍ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺖ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﮐﺎﺭﺑﺮﺍﻥ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ‪ NAS‬ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻣﺮﺑﻮﻃﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺷﺒﮑﻪ‬

‫ﺳﺎﺯﻣﺎﻥ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫‪251‬‬

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‫ﺳﺎﻳﺖ ﺑﻪ ﺳﺎﻳﺖ )‪ . (Site-to-Site‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬

‫ﺳﻴﺎﺳﺖ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺗﺼﺎﻝ ﭼﻨﺪﻳﻦ ﺳﺎﻳﺖ ﺛﺎﺑﺖ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﻋﻤﻮﻣﻲ ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﮐﻪ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪،‬‬ ‫ﺩﺍﺭﺍﻱ ﮔﻮﻧﻪ ﻫﺎﻱ ﺧﺎﺻﻲ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬

‫ ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﻳﻨﺘﺮﺍﻧﺖ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺎﺯﻣﺎﻧﻲ ﺩﺍﺭﺍﻱ ﻳﮏ ﻭ ﻳﺎ ﺑﻴﺶ ﺍﺯ ﻳﮏ ﻣﺤﻞ‬‫) ﺭﺍﻩ ﺩﻭﺭ( ﺑﻮﺩﻩ ﻭ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﻟﺤﺎﻕ ﺁﻧﻬﺎ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺑﺎﺷﺪ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ‬

‫ﻳﮏ ﺍﻳﻨﺘﺮﺍﻧﺖ ‪ VPN‬ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﻫﺮ ﻳﮏ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﺑﺎ‬ ‫ﻳﮑﺪﻳﮕﺮ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩ‪.‬‬ ‫‪ -‬ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﮐﺴﺘﺮﺍﻧﺖ ‪ .‬ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺳﺎﺯﻣﺎﻧﻲ ﺩﺭ ﺗﻌﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺴﻴﺎﺭ ﻧﺰﺩﻳﮏ‬

‫ﺑﺎ ﺳﺎﺯﻣﺎﻥ ﺩﻳﮕﺮ ﺑﺎﺷﺪ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﺍﮐﺴﺘﺮﺍﻧﺖ ‪ VPN‬ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﻣﺤﻠﻲ ﻫﺮ ﻳﮏ ﺍﺯ ﺳﺎﺯﻣﺎﻧﻬﺎ ﺍﻳﺠﺎﺩ ﮐﺮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺳﺎﺯﻣﺎﻧﻬﺎﻱ ﻣﺘﻌﺪﺩ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﻓﻌﺎﻟﻴﺖ ﺩﺭ ﻳﮏ ﻣﺤﻴﻂ ﺍﺷﺘﺮﺍﮐﻲ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ VPN‬ﺑﺮﺍﻱ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺩﺍﺭﺍﻱ ﻣﺰﺍﻳﺎﻱ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ‪ :‬ﮔﺴﺘﺮﺵ ﻣﺤﺪﻭﻩ‬

‫ﺟﻐﺮﺍﻓﻴﺎﺋﻲ ﺍﺭﺗﺒﺎﻃﻲ‪ ،‬ﺑﻬﺒﻮﺩ ﻭﺿﻌﻴﺖ ﺍﻣﻨﻴﺖ‪ ،‬ﮐﺎﻫﺶ ﻫﺰﻳﻨﻪ ﻫﺎﻱ ﻋﻤﻠﻴﺎﺗﻲ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺭﻭﺵ‬

‫ﻫﺎﻱ ﺳﻨﺘﻲ ‪ ، WAN‬ﮐﺎﻫﺶ ﺯﻣﺎﻥ ﺍﺭﺳﺎﻝ ﻭ ﺣﻤﻞ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‪ ،‬ﺑﻬﺒﻮﺩ‬ ‫ﺑﻬﺮﻩ ﻭﺭﻱ‪ ،‬ﺗﻮﭘﻮﻟﻮﮊﻱ ﺁﺳﺎﻥ ‪ ...،‬ﺍﺳﺖ‪ .‬ﺩﺭ ﻳﮑﻪ ﺷﺒﮑﻪ ‪ VPN‬ﺑﻪ ﻋﻮﺍﻣﻞ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ‪ :‬ﺍﻣﻨﻴﺖ‪،‬‬ ‫ﺍﻋﺘﻤﺎﺩﭘﺬﻳﺮﻱ ‪ ،‬ﻣﺪﻳﺮﻳﺖ ﺷﺒﮑﻪ ﻭ ﺳﻴﺎﺳﺖ ﻫﺎ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﺟﺰﺍﻳﺮ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﻓﺮﺽ ﻧﻤﺎﺋﻴﺪ ﺩﺭ ﺟﺰﻳﺮﻩ ﺍﻱ ﺩﺭ ﺍﻗﻴﺎﻧﻮﺳﻲ ﺑﺰﺭﮒ ‪ ،‬ﺯﻧﺪﮔﻲ ﻣﻲ ﮐﻨﻴﺪ‪ .‬ﻫﺰﺍﺭﺍﻥ ﺟﺰﻳﺮﻩ ﺩﺭ‬ ‫ﺍﻃﺮﺍﻑ ﺟﺰﻳﺮﻩ ﺷﻤﺎ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺟﺰﺍﻳﺮ ﻧﺰﺩﻳﮏ ﻭ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺩﺍﺭﺍﻱ ﻣﺴﺎﻓﺖ‬ ‫ﻃﻮﻻﻧﻲ ﺑﺎ ﺟﺰﻳﺮﻩ ﺷﻤﺎ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺭﻭﺵ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺴﺎﻓﺮﺕ ﺑﻪ ﺟﺰﻳﺮﻩ ﺩﻳﮕﺮ‪،‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺸﺘﻲ ﻣﺴﺎﻓﺮﺑﺮﻱ ﺍﺳﺖ ‪ .‬ﻣﺴﺎﻓﺮﺕ ﺑﺎ ﮐﺸﺘﻲ ﻣﺴﺎﻓﺮﺑﺮﻱ‪ ،‬ﺑﻤﻨﺰﻟﻪ ﻋﺪﻡ ﻭﺟﻮﺩ‬ ‫ﺍﻣﻨﻴﺖ ﺍﺳﺖ‪.‬‬ ‫‪252‬‬

‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻫﺮ ﮐﺎﺭﻱ ﺭﺍ ﮐﻪ ﺷﻤﺎ ﺍﻧﺠﺎﻡ ﺩﻫﻴﺪ ‪ ،‬ﺗﻮﺳﻂ ﺳﺎﻳﺮ ﻣﺴﺎﻓﺮﻳﻦ ﻗﺎﺑﻞ ﻣﺸﺎﻫﺪﻩ‬

‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﻫﺮ ﻳﮏ ﺍﺯ ﺟﺰﺍﻳﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻣﺸﺎﺑﻪ ﻳﮏ ﺷﺒﮑﻪ ﻣﺤﻠﻲ )‪ (LAN‬ﻭ‬ ‫ﺍﻗﻴﺎﻧﻮﺱ ﻣﺎﻧﻨﺪ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺴﺎﻓﺮﺕ ﺑﺎ ﻳﮏ ﮐﺸﺘﻲ ﻣﺴﺎﻓﺮﺑﺮﻱ ﻣﺸﺎﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ‬ ‫ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﺏ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺖ‪ .‬ﺷﻤﺎ ﺩﺍﺭﺍﻱ‬ ‫ﻫﻴﭽﮕﻮﻧﻪ ﮐﻨﺘﺮﻟﻲ ﺑﺮ ﺭﻭﻱ ﮐﺎﺑﻞ ﻫﺎ ﻭ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻧﻤﻲ ﺑﺎﺷﻴﺪ‪ ) .‬ﻣﺸﺎﺑﻪ‬

‫ﻋﺪﻡ ﮐﻨﺘﺮﻝ ﺷﻤﺎ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺴﺎﻓﺮ ﮐﺸﺘﻲ ﻣﺴﺎﻓﺮﺑﺮﻱ ﺑﺮ ﺭﻭﻱ ﺳﺎﻳﺮ ﻣﺴﺎﻓﺮﻳﻦ ﺣﺎﺿﺮ ﺩﺭ ﮐﺸﺘﻲ‬ ‫(‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﻭ ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺍﺯ ﻃﺮﻳﻖ ﻣﻨﺎﺑﻊ ﻋﻤﻮﻣﻲ ﻭﺟﻮﺩ‬

‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﺍﻭﻟﻴﻦ ﻣﺴﺌﻠﻪ ﺍﻱ ﮐﻪ ﺑﺎ ﭼﺎﻟﺶ ﻫﺎﻱ ﺟﺪﻱ ﺑﺮﺧﻮﺭﺩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ ‪ ،‬ﺍﻣﻨﻴﺖ ﺧﻮﺍﻫﺪ‬ ‫ﺑﻮﺩ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ‪ ،‬ﺟﺰﻳﺮﻩ ﺷﻤﺎ ﻗﺼﺪ ﺍﻳﺠﺎﺩ ﻳﮏ ﭘﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺑﺎ ﺟﺰﻳﺮﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺩﺍﺷﺘﻪ‬ ‫ﺑﺎﺷﺪ ‪.‬ﻣﺴﻴﺮ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻳﮏ ﺭﻭﺵ ﺍﻳﻤﻦ‪ ،‬ﺳﺎﺩﻩ ﻭ ﻣﺴﺘﻘﻴﻢ ﺑﺮﺍﻱ ﻣﺴﺎﻓﺮﺕ ﺳﺎﮐﻨﻴﻦ ﺟﺰﻳﺮﻩ‬

‫ﺷﻤﺎ ﺑﻪ ﺟﺰﻳﺮﻩ ﺩﻳﮕﺮ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﺩ‪ .‬ﻫﻤﺎﻧﻄﻮﺭ ﮐﻪ ﺣﺪﺱ ﺯﺩﻩ ﺍﻳﺪ ‪ ،‬ﺍﻳﺠﺎﺩ ﻭ ﻧﮕﻬﺪﺍﺭﻱ‬

‫ﻳﮏ ﭘﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺑﻴﻦ ﺩﻭ ﺟﺰﻳﺮﻩ ﻣﺴﺘﻠﺰﻡ ﺻﺮﻑ ﻫﺰﻳﻨﻪ ﻫﺎﻱ ﺑﺎﻻﺋﻲ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ ).‬ﺣﺘﻲ ﺍﮔﺮ‬ ‫ﺟﺰﺍﻳﺮ ﺩﺭ ﻣﺠﺎﻭﺭﺕ ﻳﮑﺪﻳﮕﺮ ﺑﺎﺷﻨﺪ (‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺿﺮﻭﺭﺕ ﻭ ﺣﺴﺎﺳﻴﺖ ﻣﺮﺑﻮﻁ ﺑﻪ ﺩﺍﺷﺘﻦ‬

‫ﻳﮏ ﻣﺴﻴﺮ ﺍﻳﻤﻦ ﻭ ﻣﻄﻤﺌﻦ‪ ،‬ﺗﺼﻤﻴﻢ ﺑﻪ ﺍﻳﺠﺎﺩ ﭘﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺑﻴﻦ ﺩﻭ ﺟﺰﻳﺮﻩ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺟﺰﻳﺮﻩ ﺷﻤﺎ ﻗﺼﺪ ﺍﻳﺠﺎﺩ ﻳﮏ ﭘﻞ ﺍﺭﺗﺒﺎﻃﻲ ﺑﺎ ﺟﺰﻳﺮﻩ ﺩﻳﮕﺮ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ﮐﻪ‬ ‫ﺩﺭ ﻣﺴﺎﻓﺖ ﺑﺴﻴﺎﺭ ﻃﻮﻻﻧﻲ ﻧﺴﺒﺖ ﺑﻪ ﺟﺰﻳﺮﻩ ﺷﻤﺎ ﻭﺍﻗﻊ ﺍﺳﺖ‬ ‫‪ ،‬ﻫﺰﻳﻨﻪ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻭﺿﻌﻴﺖ ﻓﻮﻕ‪ ،‬ﻧﻈﻴﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ‬

‫ﺍﺧﺘﺼﺎﺻﻲ ‪ Leased‬ﺍﺳﺖ‪ .‬ﻣﺎﻫﻴﺖ ﭘﻞ ﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ ) ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ( ﺍﺯ ﺍﻗﻴﺎﻧﻮﺱ‬ ‫) ﺍﻳﻨﺘﺮﻧﺖ ( ﻣﺘﻔﺎﻭﺕ ﺑﻮﺩﻩ ﻭ ﮐﻤﺎﮐﻦ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺟﺰﺍﻳﺮ) ﺷﺒﮑﻪ ﻫﺎﻱ ‪ (LAN‬ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﻣﺘﻌﺪﺩﻱ ﺍﺯ ﺭﻭﻳﮑﺮﺩ ﻓﻮﻕ ) ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ( ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﻋﺎﻣﻞ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻭﺟﻮﺩ ﺍﻣﻨﻴﺖ ﻭ ﺍﻃﻤﻴﻨﺎﻥ ﺑﺮﺍﻱ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﻫﺮ‬ ‫ﻳﮏ ﺳﺎﺯﻣﺎﻧﻬﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺴﺎﻓﺖ ﺍﺩﺍﺭﺍﺕ ﻭ ﻳﺎ ﺷﻌﺐ ﻳﮏ‬ ‫ﺳﺎﺯﻣﺎﻥ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﺑﺴﻴﺎﺭ ﺩﻭﺭ ﺑﺎﺷﺪ‪ ،‬ﻫﺰﻳﻨﻪ ﻣﺮﺑﻮﻁ ﺑﻪ ﺑﺮﻗﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﻧﻴﺰ ﺍﻓﺰﺍﻳﺶ ﺧﻮﺍﻫﺪ‬

‫ﻳﺎﻓﺖ‪.‬‬

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‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﻮﺍﺭﺩ ﮔﻔﺘﻪ ﺷﺪﻩ‪ ،‬ﭼﻪ ﺿﺮﻭﺭﺗﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ VPN‬ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﻭ‬

‫‪ VPN‬ﺗﺎﻣﻴﻦ ﮐﻨﻨﺪﻩ‪ ،‬ﮐﺪﺍﻣﻴﮏ ﺍﺯ ﺍﻫﺪﺍﻑ ﻭ ﺧﻮﺍﺳﺘﻪ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺳﺖ؟ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬ ‫ﻣﻘﺎﻳﺴﻪ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺩﺭ ﻣﺜﺎﻝ ﻓﺮﺿﻲ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﮔﻔﺖ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ VPN‬ﺑﻪ ﻫﺮﻳﮏ ﺍﺯ‬ ‫ﺳﺎﮐﻨﻴﻦ ﺟﺰﻳﺮﻩ ﻳﮏ ﺯﻳﺮﺩﺭﻳﺎﺋﻲ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺯﻳﺮﺩﺭﻳﺎﺋﻲ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﺧﺼﺎﻳﺺ ﻣﺘﻔﺎﻭﺕ‬

‫ﻧﻈﻴﺮ ‪:‬‬ ‫•‬ ‫•‬

‫ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ﺑﺎﻻ ﺍﺳﺖ‪.‬‬ ‫ﻫﺪﺍﻳﺖ ﺁﻥ ﺳﺎﺩﻩ ﺍﺳﺖ‪.‬‬

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‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﺘﺎﺭ) ﻣﺨﻔﻲ ﻧﻤﻮﺩﻥ( ﺷﻤﺎ ﺍﺯ ﺳﺎﻳﺮ ﺯﻳﺮﺩﺭﻳﺎ ﺋﻴﻬﺎ ﻭ ﮐﺸﺘﻲ ﻫﺎ ﺍﺳﺖ‪.‬‬

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‫ﻗﺎﺑﻞ ﺍﻋﺘﻤﺎﺩ ﺍﺳﺖ ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﺗﺎﻣﻴﻦ ﺍﻭﻟﻴﻦ ﺯﻳﺮﺩﺭﻳﺎﺋﻲ ‪ ،‬ﺍﻓﺰﻭﺩﻥ ﺍﻣﮑﺎﻧﺎﺕ ﺟﺎﻧﺒﻲ ﻭ ﺣﺘﻲ ﻳﮏ ﺯﻳﺮﺩﺭﻳﺎﺋﻲ‬ ‫ﺩﻳﮕﺮﻣﻘﺮﻭﻥ ﺑﻪ ﺻﺮﻓﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‬

‫ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﺑﺎ ﻭﺟﻮﺩ ﺗﺮﺍﻓﻴﮏ ﺩﺭ ﺍﻗﻴﺎﻧﻮﺱ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﺳﺎﮐﻨﻴﻦ ﺩﻭ ﺟﺰﻳﺮﻩ ﻗﺎﺩﺭ ﺑﻪ ﺗﺮﺩﺩ ﺩﺭ‬ ‫ﻃﻮﻝ ﻣﺴﻴﺮ ﺩﺭ ﺯﻣﺎﻥ ﺩﻟﺨﻮﺍﻩ ﺧﻮﺩ ﺑﺎ ﺭﻋﺎﻳﺖ ﻣﺴﺎﻳﻞ ﺍﻳﻤﻨﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﺎﻝ ﻓﻮﻕ ﺩﻗﻴﻘﺎ" ﺑﻴﺎﻧﮕﺮ‬ ‫ﺗﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ‪ VPN‬ﺍﺳﺖ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺷﺒﮑﻪ ﻗﺎﺩﺭﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻃﻲ‬ ‫ﺍﻣﻦ ﻭ ﻣﻄﻤﺌﻦ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻋﻤﻮﻣﻲ ) ﻧﻈﻴﺮ ﺍﻳﻨﺘﺮﻧﺖ ( ﺑﺎ ﺷﺒﮑﻪ ﻣﺤﻠﻲ‬

‫)‪ (LAN‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﺎﺯﻣﺎﻥ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺗﻮﺳﻌﻪ ﻳﮏ ‪ ) VPN‬ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ‬ ‫ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﻭ ﻳﺎ ﺍﻓﺰﺍﻳﺶ ﻣﮑﺎﻥ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ( ﺑﻤﺮﺍﺗﺐ ﺁﺳﺎﻧﺘﺮ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﺍﺯ‬

‫ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻗﺎﺑﻠﻴﺖ ﺗﻮﺳﻌﻪ ﻓﺮﺍﮔﻴﺮ ﺍﺯ ﻣﻬﻤﺘﺰﻳﻦ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻳﮏ‬

‫‪ VPN‬ﻧﺴﺒﺖ ﺑﻪ ﺧﻄﻮﻁ ﺍﺧﺘﺼﺎﺻﻲ ﺍﺳﺖ‪.‬‬ ‫ﺍﻣﻨﻴﺖ ‪VPN‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺎﻣﻴﻦ ﺍﻣﻨﻴﺖ )ﺩﺍﺩﻩ ﻫﺎ ﻭ ﺍﺭﺗﺒﺎﻃﺎﺕ( ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪:‬‬

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‫ﻓﺎﻳﺮﻭﺍﻝ ‪ .‬ﻓﺎﻳﺮﻭﺍﻝ ﻳﮏ ﺩﻳﻮﺍﺭﻩ ﻣﺠﺎﺯﻱ ﺑﻴﻦ ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﻱ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﻭ ﺍﻳﻨﺘﺮﻧﺖ‬ ‫ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺎﻳﺮﻭﺍﻝ ﻣﻲ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺩﺭ ﺟﻬﺖ ﺍﻋﻤﺎﻝ‬ ‫ﺳﻴﺎﺳﺖ ﻫﺎﻱ ﺍﻣﻨﻴﺘﻲ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪ .‬ﺍﻳﺠﺎﺩ ﻣﺤﺪﻭﺩﻳﺖ ﺩﺭ ﺗﻌﺪﺍﺩ ﭘﻮﺭﺕ ﻫﺎ‬

‫ﻓﻌﺎﻝ ‪ ،‬ﺍﻳﺠﺎﺩ ﻣﺤﺪﻭﺩﻳﺖ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﻪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺧﺎﺹ ‪ ،‬ﺍﻳﺠﺎﺩ ﻣﺤﺪﻭﺩﻳﺖ ﺩﺭ‬

‫ﻧﻮﻉ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ‪ ...‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﻋﻤﻠﻴﺎﺗﻲ ﺍﺳﺖ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﻳﮏ ﻓﺎﻳﺮﻭﺍﻝ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪.‬‬

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‫ﺭﻣﺰﻧﮕﺎﺭﻱ ‪ .‬ﻓﺮﺁﻳﻨﺪﻱ ﺍﺳﺖ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺒﺪﺍﺀ ﺍﻃﻼﻋﺎﺗﻲ ﺭﻣﺰﺷﺪﻩ ﺭﺍ‬ ‫ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻱ ﻣﺠﺎﺯ ﻗﺎﺩﺭ ﺑﻪ ﺭﻣﺰﮔﺸﺎﺋﻲ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﭘﺲ ﺍﺯ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ‬

‫ﻓﺮﺳﺘﻨﺪﻩ‪ ،‬ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﮔﺎﻥ‪ ،‬ﻗﺒﻞ ﺍﺯ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻗﺪﺍﻡ ﺑﻪ‬ ‫ﺭﻣﺰﮔﺸﺎﺋﻲ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺩﻭ‬

‫ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﺩ‪ :‬ﺭﻣﺰﻧﮕﺎﺭﻱ ﮐﻠﻴﺪ ﻣﺘﻘﺎﺭﻥ ﻭ ﺭﻣﺰﻧﮕﺎﺭﻱ ﮐﻠﻴﺪ ﻋـــﻤﻮﻣﻲ‬ ‫ﺩﺭ ﺭﻣﺰ ﻧﮕﺎﺭﻱ " ﮐﻠﻴﺪ ﻣﺘﻘﺎﺭﻥ " ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﮐﻠﻴﺪ ‪ ) Secret‬ﮐﺪ (‬ ‫ﺑﻮﺩﻩ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﻗﺎﺩﺭ ﺑﻪ ﺭﻣﺰﻧﮕﺎﺭﻱ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳﮕﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﻧﺴﺒﺖ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ‬

‫ﮐﻪ ﻗﺼﺪ ﺑﺮﻗﺮﺍﺭﻱ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﻳﮑﺪﻳﮕﺮ ﺭﺍ ﺩﺍﺭﻧﺪ‪ ،‬ﺁﮔﺎﻫﻲ ﮐﺎﻣﻞ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ‬

‫ﺑﺎﺷﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺮﮐﺖ ﮐﻨﻨﺪﻩ ﺩﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﮐﻠﻴﺪ‬ ‫ﺭﻣﺰ ﻣﺸﺎﺑﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺭﻣﺰﮔﺸﺎﺋﻲ ﺍﻃﻼﻋﺎﺕ ﺑﺎﺷﻨﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﻧﻴﺰ‬

‫ﺍﺯ ﮐﻠﻴﺪ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﻳﮏ ﭘﻴﺎﻡ ﺭﻣﺰ ﺷﺪﻩ ﺑﺮﺍﻱ ﻳﮑﻲ ﺍﺯ‬ ‫ﺩﻭﺳﺘﺎﻥ ﺧﻮﺩ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺍﺯ ﻳﮏ ﺍﻟﮕﻮﺭﻳﺘﻢ ﺧﺎﺹ ﺑﺮﺍﻱ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﻟﮕﻮﺭﻳﺘﻢ ﻓﻮﻕ ﻫﺮ ﺣﺮﻑ ﺑﻪ ﺩﻭﺣﺮﻑ ﺑﻌﺪ ﺍﺯ ﺧﻮﺩ ﺗﺒﺪﻳﻞ ﻣﻲ ﮔﺮﺩﺩ‪) .‬ﺣﺮﻑ ‪A‬‬

‫ﺑﻪ ﺣﺮﻑ ‪ ، C‬ﺣﺮﻑ ‪ B‬ﺑﻪ ﺣﺮﻑ ‪ .( D‬ﭘﺲ ﺍﺯ ﺭﻣﺰﻧﻤﻮﺩﻥ ﭘﻴﺎﻡ ﻭ ﺍﺭﺳﺎﻝ ﺁﻥ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﭘﻴﺎﻡ ﺑﻪ ﺍﻳﻦ ﺣﻘﻴﻘﺖ ﻭﺍﻗﻒ ﺑﺎﺷﺪ ﮐﻪ ﺑﺮﺍﻱ ﺭﻣﺰﮔﺸﺎﺋﻲ ﭘﻴﺎﻡ ﻟﺮﺳﺎﻝ ﺷﺪﻩ‪ ،‬ﻫﺮ‬ ‫ﺣﺮﻑ ﺑﻪ ﺩﻭ ﺣﺮﻕ ﻗﺒﻞ ﺍﺯ ﺧﻮﺩ ﻣﻲ ﺑﺎﻳﺴﺖ ﺗﺒﺪﻳﻞ ﮔﺮﺩﺩ‪.‬‬ ‫‪255‬‬

‫ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺩﻭﺳﺖ ﺍﻣﻴﻦ ﺧﻮﺩ‪ ،‬ﻭﺍﻗﻌﻴﺖ ﻓﻮﻕ ) ﮐﻠﻴﺪ ﺭﻣﺰ ( ﮔﻔﺘﻪ‬

‫ﺷﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﻴﺎﻡ ﻓﻮﻕ ﺗﻮﺳﻂ ﺍﻓﺮﺍﺩ ﺩﻳﮕﺮﻱ ﺩﺭﻳﺎﻓﺖ ﮔﺮﺩﺩ‪ ،‬ﺑﺪﻟﻴﻞ ﻋﺪﻡ ﺁﮔﺎﻫﻲ ﺍﺯ‬ ‫ﮐﻠﻴﺪ‪ ،‬ﺁﻧﺎﻥ ﻗﺎﺩﺭ ﺑﻪ ﺭﻣﺰﮔﺸﺎﺋﻲ ﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻴﺎﻡ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺩﺭ ﺭﻣﺰﻧﮕﺎﺭﻱ ﻋﻤﻮﻣﻲ ﺍﺯ ﺗﺮﮐﻴﺐ ﻳﮏ ﮐﻠﻴﺪ ﺧﺼﻮﺻﻲ ﻭ ﻳﮏ ﮐﻠﻴﺪ ﻋﻤﻮﻣﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﮐﻠﻴﺪ ﺧﺼﻮﺻﻲ ﺻﺮﻓﺎ" ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ) ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ( ﻗﺎﺑﻞ ﺷﻨﺎﺳﺎﺋﻲ ﻭ ﺍﺳﺘـﻔﺎﺩﻩ ﺍﺳﺖ‪.‬‬ ‫ﮐﻠﻴﺪ ﻋﻤﻮﻣﻲ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺩﻳﮕﺮ ﮐﻪ ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺁﻥ‬

‫ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ ‪ ،‬ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺭﻣﺰﮔﺸﺎﺋﻲ ﻳﮏ ﭘﻴﺎﻡ ﺭﻣﺰ ﺷﺪﻩ‪ ،‬ﻳﮏ ﮐﺎﻣﭙﻴـﻮﺗﺮ‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﻠﻴﺪ ﻋﻤﻮﻣﻲ ) ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ( ‪ ،‬ﮐﻠــﻴﺪ‬ ‫ﺧﺼﻮﺻﻲ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺍﻗﺪﺍﻡ ﺑﻪ ﺭﻣﺰﮔﺸﺎﺋﻲ ﭘﻴﺎﻡ ﺍﺭﺳﺎﻟﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﻳﮑﻲ ﺍﺯ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺍﺑﺰﺍﺭ‬

‫"ﺭﻣﺰﻧﮕﺎﺭﻱ ﮐﻠﻴﺪ ﻋﻤﻮﻣﻲ"‪ ،‬ﺭﻭﺷﻲ ﺑﺎ ﻧﺎﻡ ‪ (Pretty Good Privacy(PGP‬ﺍﺳﺖ‪.‬‬ ‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻥ ﺍﻗﺪﺍﻡ ﺑﻪ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﻃﻼﻋﺎﺕ ﺩﻟﺨﻮﺍﻩ ﺧﻮﺩ ﻧﻤﻮﺩ‪.‬‬ ‫•‬

‫‪ . IPSec‬ﭘﺮﻭﺗﮑﻞ ‪، (protocol Internet protocol security(IPsec‬‬

‫ﻳﮑﻲ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻣﻮﺟﻮﺩ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺍﻣﻨــــﻴﺖ ﺩﺭ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓـــــﺖ ﺍﻃﻼﻋﺎﺕ‬

‫ﻣﻲ ﺑﺎﺷﺪ ‪ .‬ﻗﺎﺑﻠﻴﺖ ﺭﻭﺵ ﻓﻮﻕ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺍﻟﮕﻮﺭﻳﺘﻢ ﻫﺎﻱ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ‬ ‫ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﺩﻭ ﺭﻭﺵ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﺳﺖ ‪. Transport ،Tunnel :‬‬ ‫ﺩﺭ ﺭﻭﺵ ‪ ، tunel‬ﻫﺪﺭ ﻭ ‪ Payload‬ﺭﻣﺰ ﺷﺪﻩ ﺩﺭﺣﺎﻟﻴﮑﻪ ﺩﺭ ﺭﻭﺵ ‪transport‬‬

‫ﺻﺮﻓﺎ" ‪ payload‬ﺭﻣﺰ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﻗﺎﺩﺭ ﺑﻪ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﻃﻼﻋــﺎﺕ ﺑﻴﻦ‬ ‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪:‬‬ ‫‪ -‬ﺭﻭﺗﺮ ﺑﻪ ﺭﻭﺗﺮ‬

‫ ﻓﺎﻳﺮﻭﺍﻝ ﺑﻪ ﺭﻭﺗﺮ‬‫ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ‬‫‪ -‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ . AAA‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ) ‪Authentication : AAA‬‬

‫‪ (Authorization,Accounting,‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺍﻣﻨﻴﺖ ﺑﺎﻻ ﺩﺭ ﻣﺤﻴﻂ ﻫـﺎﻱ‬

‫‪ VPN‬ﺍﺯ ﻧﻮﻉ " ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ " ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﺧﻂ ﺗﻠﻔﻦ ﺑﻪ ﺳﻴﺴﺘﻢ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ AAA‬ﺩﺭﺧﻮﺍﺳﺖ ﺁﻧﻬﺎ‬ ‫ﺭﺍ ﺍﺧﺬ ﻭ ﻋﻤﺎﻳﺎﺕ ﺯﻳﺮ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ‪:‬‬ ‫‪ -‬ﺷﻤﺎ ﭼﻪ ﮐﺴﻲ ﻫﺴﺘﻴﺪ؟ ) ﺗﺎﻳﻴﺪ‪( Authentication ،‬‬

‫ ﺷﻤﺎ ﻣﺠﺎﺯ ﺑﻪ ﺍﻧﺠﺎﻡ ﭼﻪ ﮐﺎﺭﻱ ﻫﺴﺘﻴﺪ؟ ) ﻣﺠﻮﺯ‪( Authorization ،‬‬‫ ﭼﻪ ﮐﺎﺭﻫﺎﺋﻲ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩﻩ ﺍﻳﺪ؟ ) ﺣﺴﺎﺑﺪﺍﺭﻱ‪( Accounting ،‬‬‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ‪VPN‬‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ‪ " ) VPN‬ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ " ﻭ ﻳﺎ " ﺳﺎﻳﺖ ﺑﻪ ﺳﺎﻳﺖ " ( ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺍﻳﺠﺎﺩ ﺷﺒﮑﻪ ﺍﺯ ﻋﻨﺎﺻﺮ ﺧﺎﺻﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‬

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‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺍﺧﺘﺼﺎﺻﻲ ﻧﻈﻴﺮ ﻳﮏ " ﮐﺎﻧﮑﺘﻮﺭ ‪ "VPN‬ﻭ ﻳﺎ ﻳﮏ ﻓﺎﻳﺮﻭﺍﻝ ‪PIX‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺧﺘﺼﺎﺻﻲ ‪ VPN‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺳﺮﻭﻳ‪‬ﺲ ﻫﺎﻱ ‪Dial-up‬‬

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‫ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ NAS‬ﮐﻪ ﺗﻮﺳﻂ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ‬ ‫‪ VPN‬ﺍﺯ ﻧﻮﻉ "ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍ ﺩﻭﺭ" ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﺷﺒﮑﻪ ‪ VPN‬ﻭ ﻣﺮﮐﺰ ﻣﺪﻳﺮﻳﺖ ﺳﻴﺎﺳﺖ ﻫﺎ‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺗﺎﮐﻨﻮﻥ ﻳﮏ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻗﺎﺑﻞ ﻗﺒﻮﻝ ﻭ ﻋﻤﻮﻣﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺵ‪VPN‬‬ ‫ﺍﻳﺠﺎﺩ ﻧﺸﺪﻩ ﺍﺳﺖ‪ ،‬ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻫﺮ ﻳﮏ ﺍﻗﺪﺍﻡ ﺑﻪ ﺗﻮﻟﻴﺪ ﻣﺤﺼﻮﻻﺕ ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ‬

‫ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪.‬‬ ‫•‬

‫ﮐﺎﻧﮑﺘﻮﺭ ‪ . VPN‬ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻓﻮﻕ ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﺳﻴﺴﮑﻮ ﻃﺮﺍﺣﻲ ﻭ ﻋﺮﺿﻪ ﺷﺪﻩ‬ ‫ﺍﺳﺖ‪ .‬ﮐﺎﻧﮑﺘﻮﺭ ﻓﻮﻕ ﺩﺭ ﻣﺪﻝ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻭ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﮔﻮﻧﺎﮔﻮﻥ ﻋﺮﺿﻪ ﺷﺪﻩ‬

‫ﺍﺳﺖ ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﺍﺯ ﻧﻤﻮﻧﻪ ﻫﺎﻱ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﻓﻌﺎﻟﻴﺖ ﻫﻤﺰﻣﺎﻥ ‪ ١٠٠‬ﮐﺎﺭﺑﺮ ﺍﺯ‬

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‫ﺭﺍﻩ ﺩﻭﺭ ﻭ ﺩﺭ ﺑﺮﺧﻲ ﻧﻤﻮﻧﻪ ﻫﺎﻱ ﺩﻳﮕﺮ ﺗﺎ ‪ ١٠,٠٠٠‬ﮐﺎﺭﺑﺮ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﻗﺎﺩﺭ ﺑﻪ ﺍﺗﺼﺎﻝ‬

‫ﺑﻪ ﺷﺒﮑﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫•‬

‫ﺭﻭﺗﺮ ﻣﺨﺘﺺ ‪ . VPN‬ﺭﻭﺗﺮ ﻓﻮﻕ ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﺳﻴﺴﮑﻮ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﺭﻭﺗﺮ‬ ‫ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﻣﺤﻴﻂ ﻫﺎﻱ ﮔﻮﻧﺎﮔﻮﻥ ﺍﺳﺖ‪.‬‬

‫ﺩﺭ ﻃﺮﺍﺣﻲ ﺭﻭﺗﺮ ﻓﻮﻕ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﻧﻴﺰ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﺍﻣﮑﺎﻧﺎﺕ‬ ‫ﻣﺮﺑﻮﻁ ﺩﺭ ﺁﻥ ﺑﮕﻮﻧﻪ ﺍﻱ ﺑﻬﻴﻨﻪ ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬

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‫ﻓﺎﻳﺮﻭﺍﻝ ‪ ) . PIX‬ﻓﺎﻳﺮﻭﺍﻝ ‪ eXchange Private Internet) PIX‬ﻗﺎﺑﻠﻴﺖ‬ ‫ﻫﺎﺋﻲ ﻧﻈﻴﺮ ‪ ، NAT‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ،Proxy‬ﻓﻴﻠﺘﺮ ﻧﻤﻮﺩﻥ ﺑﺴﺘﻪ ﺍﻱ ﺍﻃﻼﻋﺎﺗﻲ‪،‬‬

‫ﻓﺎﻳﺮﻭﺍﻝ ﻭ ‪ VPN‬ﺭﺍ ﺩﺭ ﻳﮏ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪.‬‬ ‫‪ )Tunneling‬ﺗﻮﻧﻞ ﺳﺎﺯﻱ (‬

‫ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ‬

‫ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﺍﻣﮑﺎﻥ " ‪ " Tunneling‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﺗﻤﺎﻡ ﺑﺴﺘﻪ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻳﮏ ﺑﺴﺘﻪ ﺩﻳﮕﺮ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﭘﺮﻭﺗﮑﻞ‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺧﺎﺭﺟﻲ ) ﭘﻮﺳﺘﻪ ( ﺗﻮﺳﻂ ﺷﺒﮑﻪ ﻭ ﺩﻭ ﻧﻔﻄﻪ )ﻭﺭﻭﺩ ﻭ ﺧﺮﻭﺝ‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ( ﻗﺎﺑﻞ ﻓﻬﻢ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﻭ ﻧﻘﻈﻪ ﻓﻮﻕ ﺭﺍ "ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺗﻮﻧﻞ " ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬ ‫ﺭﻭﺵ ﻓﻮﻕ ﻣﺴﺘﻠﺰﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻪ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺖ‪:‬‬ ‫•‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ﺣﻤﻞ ﮐﻨﻨﺪﻩ ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺷﺒﮑﻪ ﺣﺎﻣﻞ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ﮐﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﻧﻈﻴﺮ‪:‬‬

‫‪ IPSec,L2F,PPTP,L2TP,GRE‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﭘﺮﻭﺗﮑﻞ ﻣﺴﺎﻓﺮ ‪ .‬ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﺋﻲ ﻧﻈﻴﺮ ‪ IPX,IP,NetBeui‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ‬ ‫ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ‪ Tunneling‬ﻣﻲ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﺟﺎﻟﺒﻲ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬ ‫ﺑﺴﺘﻪ ﺍﻱ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻪ ﭘﺮﻭﺗﮑﻞ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺣﻤﺎﻳﺖ ﻧﻤﻲ ﮐﻨﺪ ) ﻧﻈﻴﺮ ‪ (NetBeui‬ﺩﺭﻭﻥ ﻳﮏ‬ ‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ‪ IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺁﻥ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺭﺳﺎﻝ ﻧﻤﻮﺩ‬ ‫‪258‬‬

‫ﻭ ﻳﺎ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﮐﻪ ﺍﺯ ﻳﮏ ﺁﺩﺭﺱ ‪ IP‬ﻏﻴﺮ ﻗﺎﺑﻞ ﺭﻭﺕ ) ﺍﺧﺘﺼﺎﺻﻲ (‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﺩﺭﻭﻥ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻪ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻌﺘﺒﺮ ‪ IP‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﺪ‪،‬‬ ‫ﻣﺴﺘﻘﺮ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺭﺳﺎﻝ ﻧﻤﻮﺩ‪.‬‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﺍﺯ ﻧﻮﻉ " ﺳﺎﻳﺖ ﺑﻪ ﺳﺎﻳﺖ " ‪generic routing (GRE ،‬‬

‫‪ (encapsulation‬ﺑﻪ ﻋﻨﻮﺍﻥ ﭘﺮﻭﺗﮑﻞ ﮐﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‬ ‫ﻧﺤﻮﻩ ﺍﺳﺘﻘﺮﺍﺭ ﻭ ﺑﺴﺘﻪ ﺑﻨﺪﻱ " ﭘﺮﻭﺗﮑﻞ ﻣﺴﺎﻓﺮ" ﺍﺯ ﻃﺮﻳﻖ ﭘﺮﻭﺗﮑﻞ " ﺣﻤﻞ ﮐﻨﻨﺪﻩ " ﺑﺮﺍﻱ ﺍﻧﺘﻘﺎﻝ‬ ‫ﺭﺍ ﺗﺒﻴﻦ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ) .‬ﭘﺮﻭﺗﮑﻞ ﺣﻤﻞ ﮐﻨﻨﺪﻩ ‪ ،‬ﻋﻤﻮﻣﺎ" ‪ IP‬ﺍﺳﺖ(‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﻮﻉ ﺑﺴﺖ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﮐﭙﺴﻮﻟﻪ ﻧﻤﻮﺩﻥ ﻭ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺭﺗﺒﺎﻁ‬

‫ﺑﻴﻦ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ ) IPSec‬ﺩﺭ‬ ‫ﺣﺎﻟﺖ ‪ (tunnel‬ﺑﺮﺍﻱ ﮐﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬ﭘﺮﻭﺗﮑﻞ ‪ ، IPSec‬ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺩﺭ ﺩﻭ ﻧﻮﻉ ﺷﺒﮑﻪ ‪ ) VPN‬ﺳﺎﻳﺖ ﺑﻪ ﻳﺎﻳﺖ ﻭ ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ( ﺍﺳﺖ‪ .‬ﺍﻳﻨﺘﺮﻓﻴﺶ ﻫﺎﻱ‬ ‫‪ Tunnel‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﺍﻣﮑﺎﻧﺎﺕ ﺣﻤﺎﻳﺘﻲ ﺍﺯ ‪ IPSec‬ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ VPN‬ﺍﺯ ﻧﻮﻉ " ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ " ‪ Tunneling ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪PPP‬‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪ PPP .‬ﺑﻪ ﻋﻨﻮﺍﻥ ﺣﻤﻞ ﮐﻨﻨﺪﻩ ﺳﺎﻳﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪ IP‬ﺩﺭ ﺯﻣﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﻳﮏ ﺳﻴﺴﺘﻢ ﻣﻴﺰﺑﺎﻥ ﻭ ﻳﮏ ﺳﻴﺴﺘﻢ ﺍﺯﻩ ﺩﻭﺭ ‪ ،‬ﻣﻮﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﺩ‪.‬‬ ‫ﻫﺮ ﻳﮏ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺯﻳﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺎﺧﺘﺎﺭ ﺍﻭﻟﻴﻪ ‪ PPP‬ﺍﻳﺠﺎﺩ ﻭ ﺗﻮﺳﻂ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫‪ VPN‬ﺍﺯ ﻧﻮﻉ " ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ " ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪:‬‬ ‫•‬

‫‪ . (Layer 2 Forwarding(F٢L‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺗﻮﺳﻂ ﺳﻴﺴﮑﻮ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‬ ‫ﺍﺳﺖ ‪ .‬ﺩﺭ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﺗﻌﻴﻴﻦ ﺍﻋﺘﺒﺎﺭ ﮐﺎﺭﺑﺮ ﮐﻪ ﺗﻮﺳﻂ ‪ PPP‬ﺣﻤﺎﻳﺖ‬ ‫ﺷﺪﻩ ﺍﻧﺪ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪ ﻩ ﺍﺳﺖ‪.‬‬

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‫‪ . (Point-to-Point Tunneling Protocol(PPTP‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ‬ ‫ﺗﻮﺳﻂ ﮐﻨﺴﺮﺳﻴﻮﻣﻲ ﻣﺘﺸﮑﻞ ﺍﺯ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺍﻳﻦ ﭘﺮﻭﺗﮑﻞ‬ ‫ﺍﻣﮑﺎﻥ ﺭﻣﺰﻧﮕﺎﺭﻱ ‪ ٤٠‬ﺑﻴﺘﻲ ﻭ ‪ ١٢٨‬ﺑﻴﺘﻲ ﺭﺍ ﺩﺍﺭﺍ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﺗﺎﺋﻴﺪ ﺍﻋﺘﺒﺎﺭ‬ ‫ﮐﺎﺭﺑﺮ ﮐﻪ ﺗﻮﺳﻂ ‪ PPP‬ﺣﻤﺎﻳﺖ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪259‬‬

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‫‪ . (Layer 2 Tunneling Protocol(L2TP‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺎ ﻫﻤﮑﺎﺭﻱ‬ ‫ﭼﻨﺪﻳﻦ ﺷﺮﮐﺖ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ‪ PPTP‬ﻭ ‪L2F‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﺍﺳﺖ‪ .‬ﭘﺮﻭﺗﮑﻞ ‪ L2TP‬ﺑﺼﻮﺭﺕ ﮐﺎﻣﻞ ‪ IPSec‬ﺭﺍ ﺣﻤﺎﻳﺖ ﻣﻲ ﮐﻨﺪ‪.‬‬ ‫ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﺗﻮﻧﻞ ﺑﻴﻦ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪:‬‬

‫ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺭﻭﺗﺮ‬‫ ‪ NAS‬ﻭ ﺭﻭﺗﺮ‬‫‪ -‬ﺭﻭﺗﺮ ﻭ ﺭﻭﺗﺮ‬

‫ﻋﻤﻠﮑﺮﺩ ‪ Tunneling‬ﻣﺸﺎﺑﻪ ﺣﻤﻞ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﻴﻮﻥ ﺍﺳﺖ ‪ .‬ﻓﺮﻭﺷﻨﺪﻩ ‪،‬‬ ‫ﭘﺲ ﺍﺯ ﺑﺴﺘﻪ ﺑﻨﺪﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ) ﭘﺮﻭﺗﮑﻞ ﻣﺴﺎﻓﺮ ( ﺩﺭﻭﻥ ﻳﮏ ﺟﻌﺒﻪ ) ﭘﺮﻭﺗﮑﻞ ﮐﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ (‬ ‫ﺁﻥ ﺭﺍ ﺗﻮﺳﻂ ﻳﮏ ﮐﺎﻣﻴﻮﻥ ) ﭘﺮﻭﺗﮑﻞ ﺣﻤﻞ ﮐﻨﻨﺪﻩ ( ﺍﺯ ﺍﻧﺒﺎﺭ ﺧﻮﺩ ) ﺍﻳﺘﺮﻓﻴﺲ ﻭﺭﻭﺩﻱ ﺗﻮﻧﻞ (‬ ‫ﺑﺮﺍﻱ ﻣﺘﻘﺎﺿﻲ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪.‬‬

‫ﮐﺎﻣﻴﻮﻥ ) ﭘﺮﻭﺗﮑﻞ ﺣﻤﻞ ﮐﻨﻨﺪﻩ ( ﺍﺯ ﻃﺮﻳﻖ ﺑﺰﺭﮔﺮﺍﻩ ) ﺍﻳﻨﺘﺮﻧﺖ ( ﻣﺴﻴﺮ ﺧﻮﺩ ﺭﺍ ﻃﻲ‪ ،‬ﺗﺎ ﺑﻪ‬ ‫ﻣﻨﺰﻝ ﺷﻤﺎ ) ﺍﻳﻨﺘﺮﻓﻴﺶ ﺧﺮﻭﺟﻲ ﺗﻮﻧﻞ ( ﺑﺮﺳﺪ‪ .‬ﺷﻤﺎ ﺩﺭ ﻣﻨﺰﻝ ﺟﻌﺒﻪ ) ﭘﺮﻭﺗﮑﻞ ﮐﭙﺴﻮﻝ‬ ‫ﺳﺎﺯﻱ ( ﺭﺍ ﺑﺎﺯ ﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ) ﭘﺮﻭﺗﮑﻞ ﻣﺴﺎﻓﺮ( ﺭﺍ ﺍﺯ ﺁﻥ ﺧﺎﺭﺝ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﺍﺷﺘﺮﺍﮎ ﻣﻨﺎﺑﻊ‬ ‫ﻳﮑﻲ ﺍﺯ ﺍﻫﺪﺍﻑ ﺍﻭﻟﻴﻪ ﻭ ﻣﻬﻢ ﺩﺭﺑﺮﭘﺎﺳﺎﺯﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ‪،‬ﺍﺷﺘﺮﺍﮎ ﻣﻨﺎﺑﻊ ﺍﺳﺖ‪.‬‬

‫ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﻣﻨﺎﺑﻊ ﻓﻴﺰﻳﮑﻲ )ﭼﺎﭘﮕﺮ( ﻭ ﻣﻨﺎﺑﻊ ﻣﻨﻄﻘﻲ ) ﻓﺎﻳﻞ‬ ‫ﻫﺎ( ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﭘﺲ ﺍﺯ ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺑﺴﺘﺮ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‬ ‫ﻋﻤﻠﻴﺎﺕ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪:‬‬ ‫•‬

‫ﺍﺷﺘﺮﺍﮎ ﻳﮏ ﭼﺎﭘﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺧﻂ ﺍﺭﺗﺒﺎﻃﻲ ﺍﻳﻨﺘﺮﻧﺖ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬

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‫ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ ﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﻣﺤﺘﻮﻳﺎﺕ ﻣﺘﻔﺎﻭﺕ‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺎﺯﻳﻬﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﭼﻨﺪﻳﻦ ﮐﺎﺭﺑﺮ ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺍﺯ ﺁﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺍﺭﺳﺎﻝ ﺧﺮﻭﺟﻲ ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ ﻧﻈﻴﺮ ﺩﻭﺭﺑﻴﻦ ﻫﺎﻱ ﻭﺏ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺩﺭﺷﺒﮑﻪ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮ ﭘﺎ ﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻮﭼﮏ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺭﺍ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩ‬ ‫‪:‬‬ ‫•‬

‫ﺍﻧﺘﺨﺎﺏ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺟﻬﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ‪ .‬ﺍﺗﺮﻧﺖ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﻬﻤﺘﺮﻳﻦ‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻣﻄﺮﺡ ﺍﺳﺖ‪.‬‬

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‫ﺗﻬﻴﻪ ﻭ ﻧﺼﺐ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻳﮏ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﺎﺷﻨﺪ‪.‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺳﺘﺎﺭﻩ‬

‫)ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻧﻮﻉ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺍﺳﺖ( ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮑﺪﺳﺘﮕﺎﻩ ﻫﺎﺏ ﻭ‬ ‫ﺩﺭ ﻣﻮﺍﺭﺩ ﺣﺮﻓﻪ ﺍﻱ ﺗﺮ ﺍﺯ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺳﻮﺋﻴﭻ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﭘﺲ ﺍﺯ ﻧﺼﺐ ﻭ‬

‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ) ﻋﻤﻮﻣﺎ" ﺍﺯ ﮐﺎﺑﻞ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ‪ Cat5‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ( ﻫﺮ ﻳﮏ‬

‫ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻪ ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

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‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﺳﻴﺴﺘﻢ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻨﺎﺑﻊ ﻣﺸﺘﺮﮎ ﺩﺭ ﺳﻴﺴﺘﻢ ‪ :‬ﺍﻳﻦ ﻣﺮﺣـــﻠﻪ‬

‫) ﭘﻴﮑﺮﺑﻨﺪﻱ ﺳﻴﺴﺘﻢ (‪ ،‬ﻳﮑﻲ ﺍﺯ ﻣﺮﺍﺣﻞ ﻣﻬﻢ ﺩﺭ ﺯﻣﻴﻨﻪ ﺁﻣﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺒـــــﮑﻪ ﺑﺮﺍﻱ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺖ‪.‬ﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﻋﻤﻠﻴﺎﺕ ﺯﻳﺮﺻﻮﺭﺕ ﭘﺬﻳﺮﺩ‪:‬‬

‫ ﻧﺎﻣﮕﺬﺍﺭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬‫ ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ‬‫ ﺍﺷﺘﺮﺍﮎ ﭼﺎﭘﮕﺮ‬‫‪ -‬ﺍﻣﻨﻴﺖ‬

‫ ﺍﺷﺘﺮﺍﮎ ﺧﻂ ﺍﻳﻨﺘﺮﻧﺖ‬‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻫﺮ ﻳﮏ ﺍﺯ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫ﻧﺎﻣﮕﺬﺍﺭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬

‫ﻗﺒﻞ ﺍﺯ ﺍﻳﻨﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮑﻲ ﺍﺯ ﮔﺮﻩ ﻫﺎﻱ ﺷﺒﮑﻪ ﻣﻄﺮﺡ ﮔﺮﺩﺩ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮﺍﻱ ﺁﻥ‬

‫ﻧﺎﻡ ﻭ ﻳﮏ ﮔﺮﻭﻩ ﺭﺍ ﻣﺸﺨﺺ ﮐﺮﺩ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ‬ ‫ﺩﺍﺭﺍﻱ ﻳﮏ ﻧﺎﻡ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﻭ ﻳﮏ ﻧﺎﻡ ﮔﺮﻭﻩ ﻳﮑﺴﺎﻥ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺍﻱ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﻧﺎﻡ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﮔﺮﻭﻩ‪ ،‬ﻋﻤﻠﻴﺎﺕ ﺯﻳﺮ ﺭﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﺑﺎ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭﻳﻨﺪﻭﺯ ‪ ٩٨‬ﻭ ﻳﺎ ﻣﻴﻠﻴﻨﻴﻮﻡ‪ ،‬ﻣﻮﺱ ﺭﺍ‬

‫ﺑﺮﺭﻭﻱ ‪ ) Network Neighborhood‬ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺻﻔﺤﻪ ﺍﺻﻠﻲ(‬

‫ﻗﺮﺍﺭﺩﺍﺩﻩ ﻭ ﮐﻠﻴﺪ ﺳﻤﺖ ﺭﺍﺳﺖ ﻣﻮﺱ ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Properties‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻣﻨﻮﻱ ﺩﺳﺘﻮﺭﺍﺕ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ‪ Network Properties‬ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭘﻨﺠﺮﻩ ﻓﻮﻕ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺁﺩﭘﺘﻮﺭﻫﺎﻱ ﺷﺒﮑﻪ ﻭ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻧﺼﺐ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﻧﻤﺎﻳﺶ‬

‫ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﭘﺲ ﺍﺯ ﻓﻌﺎﻝ ﺷﺪﻩ ﭘﻨﺠﺮﻩ ﺍﺷﺎﺭﻩ ﺷﺪﻩ‪ ،‬ﮔﺰﻳﻨﻪ ‪ Identification‬ﺭﺍ‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺩﺭﺍﻭﻟﻴﻦ ﻓﻴﻠﺪ ﺍﻃﻼﻋﺎﺗﻲ ‪ ،‬ﻧﺎﻡ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭﺍﺭﺩ‬

‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﺳﻪ ﻓﻴﻠﺪ ﺍﻃﻼﻋﺎﺗﻲ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﻧﻤﺎﺋﻴﺪ‪ .‬ﻧﺎﻡ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﮐﺎﻣﻼ" ﺍﻧﺘﺨﺎﺑﻲ ﺍﺳﺖ ﻭ ﺗﻨﻬﺎ ﻣﺤﺪﻭﺩﻳﺖ ﻣﻮﺟﻮﺩ‪،‬‬ ‫ﺗﮑﺮﺍﺭﻱ ﻧﺒﻮﺩﻥ ﺁﻥ ﺍﺳﺖ‪ .‬ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻧﺒﺎﻳﺪ ﺍﺯ ﻧﺎﻡ ﻓﻮﻕ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﺑﺎﺷﻨﺪ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ :‬ﺩﺭﺩﻭﻣﻴﻦ ﻓﻴﻠﺪ ﺍﻃﻼﻋﺎﺗﻲ ‪ ،‬ﻧﺎﻡ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﮔﺮﻭﻩ ﺭﺍ ﻭﺍﺭﺩ‬

‫ﻧﻤﺎﺋﻴﺪ‪ .‬ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﮐﻪ ﻗﺼﺪ ﺑﻪ ﺍﺷﺘـــــﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ ﻣﻨﺎﺑﻊ‬ ‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺑﻴﻦ ﺧﻮﺩ ﺭﺍ ﺩﺍﺭﻧﺪ ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻧﺎﻡ ﮔﺮﻭﻩ ﻣﺸﺎﺑﻪ‬ ‫ﻭ ﻳﮑﺴﺎﻥ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻭ ﺍﻣﻨﻴﺖ‬

‫ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﻫﺮ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ‪ ،‬ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ ﺍﺳﺖ‪ .‬ﺩﺭ‬

‫ﺳﻴﺴﺘﻢ ﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﻭﻳﻨﺪﻭﺯ ‪ ٩٨‬ﻭ ﻳﺎ ﻣﻴﻠﻴﻨﻴﻮﻡ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺑﺴﺎﺩﮔﻲ ﺍﻧﺠﺎﻡ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﭘﺲ ﺍﺯ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻣﻨﺎﺳﺐ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ‬

‫ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﺑﻴﻦ ﺧﻮﺩ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻓﻌﺎﻝ ﺷﺪﻥ ﮔﺰﻳﻨﻪ ‪File and‬‬

‫‪ Printer Sharing‬ﻣﻄﻤﺌﻦ ﮔﺮﺩﻳﺪ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻣﻮﺱ ﺭﺍ ﺑﺮﺭﻭﻱ ﺍﻣﮑﺎﻥ ‪Network‬‬

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‫‪ ) Neighborhood‬ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺻﻔﺤﻪ ﺍﺻﻠﻲ( ﻗﺮﺍﺭﺩﺍﺩﻩ ﻭ ﮐﻠﻴﺪ ﺳﻤﺖ ﺭﺍﺳﺖ‬

‫ﻣﻮﺱ ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬ﮔﺰﻳﻨﻪ ‪ Properties‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻣﻨﻮﻱ ﺩﺳﺘﻮﺭﺍﺕ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ‪ Network Properties‬ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﮔﺰﻳﻨﻪ ‪ Configuration‬ﻓﻌﺎﻝ ﻭ ﺩﺭ ﺑﺨﺶ ﭘﺎﻳﻴﻦ ﭘﻨﺠﺮﻩ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ‪Client‬‬

‫‪ for Microsoft Networks‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺸﺎﻫﺪﻩ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﻪ ﻋﻨﻮﺍﻥ‬ ‫ﻳﮏ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ )‪ (Client‬ﺩﺭ ﺷﺒﮑﻪ ﺍﻱ ﻣﻄﺮﺡ ﺑﺎﺷﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺗﺒﺎﺩﻝ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﺳﺎﻳﺮ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻭ ﺗﻨﻈﻴﻢ‬

‫ﺷﺒﮑﻪ ﺩﺭ ﻭﻳﻨﺪﻭﺯﻫﺎﻱ ‪ ٩٨‬ﻭ ﻳﺎ ﻣﻴﻠﻴﻨﻴﻮﻡ ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺑﺼﻮﺭﺕ‬

‫ﺍﺗﻮﻣﺎﺗﻴﮏ ﺩﺭ ﺳﻴﺴﺘﻢ ﺍﺿﺎﻓﻪ ﺧﻮﺍﻫﺪ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻣﮑﺎﻥ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ‬ ‫ﺍﺿﺎﻓﻪ ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩﻥ ﻣﺮﺍﺣﻞ ﺯﻳﺮ‪ ،‬ﺁﻥ ﺭﺍ ﻧﺼﺐ ﻧﻤﻮﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Add‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﭘﻨﺠﺮﻩ ‪ Properties Network‬ﺍﻧﺘﺨﺎﺏ‬

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‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Client‬ﺭﺍ ﺍﺯ ﻟﻴﺴﺖ ﺑﻨﻤﺎﻳﺶ ﺩﺭ ﺁﻣﺪﻩ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﻧﻤﺎﺋﻴﺪ‬

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‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﺑﺎ ﻓﻌﺎﻝ ﮐﺮﺩﻥ ﮔﺰﻳﻨﻪ ‪ Add‬ﻟﻴﺴﺘﻲ ﺍﺯ ﺷﺮﮐﺖ ﻫﺎ ﻭ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ‬ ‫ﻣﺘﻔﺎﻭﺕ ﺭﺍ ﺩﺭ ﭘﺎﻧﻞ ﺳﻤﺖ ﭼﭗ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Microsoft‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﭘﺎﻧﻞ ﺳﻤﺖ ﭼﭗ ﺍﻧﺘﺨﺎﺏ ﻭ ﺩﺭ‬

‫ﺍﺩﺍﻣﻪ ﻟﻴﺴﺘﻲ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺩﺭ ﭘﺎﻧﻞ ﺳﻤﺖ ﺭﺍﺳﺖ‬

‫ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺧﻮﻭﺍﻫﻨﺪ ﺷﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ :‬ﺍﺯ ﻟﻴﺴﺖ ﻓﻮﻕ‪ ،‬ﮔﺰﻳﻨﻪ ‪ Client for Microsoft Networks‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻭ ﺩﮐﻤﻪ ‪ OK‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭﻳﻨﺪﻭﺯ ﺗﻤﺎﻡ ﻓﺎﻳﻞ ﻫﺎﻱ‬

‫ﺿﺮﻭﺭﻱ ﻭ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ) ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ‪CD‬‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﻭﻳﻨﺪﻭﺯ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ(‬ ‫ﭘﺲ ﺍﺯ ﻧﺼﺐ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ ﺭﺍ‬

‫ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺩﺭ ﭘﻨﺠﺮﻩ ﺍﺻﻠﻲ ) ‪ ( Network‬ﺷﺒﮑﻪ ﻣﺴﺘﻔﺮ ﺷﺪﻩ ﻭ ﻣﺮﺍﺣﻞ ﺯﻳﺮ‬

‫ﺭﺍ ﺩﻧﺒﺎﻝ ﻧﻤﺎﺋﻴﺪ‪:‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﺩﮐﻤﻪ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ File and print sharing‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‬

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‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﺩﻭ ﺣﻖ ﺍﻧﺘﺨﺎﺏ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ .‬ﻳﮑﻲ ﺑﺮﺍﻱ ﺍﺷﺘﺮﺍﮎ ﻓﺎﻳﻞ ﻫﺎ‬ ‫ﻭ ﺩﻳﮕﺮﻱ ﺑﺮﺍﻱ ﺍﺷﺘﺮﺍﮎ ﭼﺎﭘﮕﺮ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﺿﻌﻴﺖ ﻣﻮﺟﻮﺩ ﺷﺒﮑﻪ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﻭ‬

‫ﻳﺎ ﻫﺮ ﺩﻭ ﺁﻳﺘﻢ ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﮐﺮﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﭘﺲ ﺍﺯ ﺍﻧﺘﺨﺎﺏ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺰﻳﻨﻪ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ) ﻓﺎﻳﻞ ‪ ،‬ﭼﺎﭘﮕﺮ (‪،‬‬

‫ﻳﮏ ‪ Checkmark‬ﺩﺭ ﮐﻨﺎﺭ ﮔﺰﻳﻨﻪ‪ File and print sharing‬ﻓﻌﺎﻝ ﺧﻮﺍﻫﺪ‬ ‫ﺷﺪ‪ .‬ﺑﺎ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﺩﮐﻤﻪ ‪ OK‬ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Sharing-options‬ﺑﺴﺘﻪ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﻣﮑﺎﻥ ‪ Access Control‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﭘﻨﺠﺮﻩ‬ ‫‪ Network‬ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﻨﺘﺮﻝ ﺳﺎﺩﻩ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻫﻮﻳﺖ ﺍﻓﺮﺍﺩﻳﮑﻲ‬

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‫ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺍﺯ ﻓﺎﻳﻞ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﮔﺰﻳﻨﻪ ‪Share-level Access Control‬‬ ‫ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ :‬ﺑﺎ ﻓﻌﺎﻝ ﮐﺮﺩﻥ ﺩﮐﻤﻪ ‪ ، OK‬ﭘﻨﺠﺮﻩ ‪ Network‬ﺑﺴﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﻓﻮﻟﺪﺭﻫﺎﺋﻲ ﺭﺍ ﮐﻪ ﻗﺼﺪ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ ﺁﻧﻬﺎ ﺭﺍ ﺩﺍﺭﻳﺪ‪ ،‬ﻣﺸﺨﺺ‬ ‫ﻧﻤﺎﺋﻴﺪ‪ .‬ﺑﺎ ﺍﻳﺠﺎﺩ ﻓﻮﻟﺪﺭﻫﺎﻱ ﺩﻟﺨﻮﺍﻩ ﻭ ﺍﺳﺘﻘﺮﺍﺭ ﻓﺎﻳﻞ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭﻫﺮ ﻳﮏ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ‬ ‫ﺍﻧﻈﺒﺎﻁ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﺑﻌﺪ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﺭﺍ ﺍﻳﺠﺎﺩ ﮐﺮﺩ‪ .‬ﺑﺮﺍﻱ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ ﻳﮏ ﻓﻮﻟﺪﺭ‬ ‫‪ ،‬ﺑﺮ ﺭﻭﻱ ﻓﻮﻟﺪﺭ ﻓﻮﻕ ﻣﺴﺘﻘﺮ ﻭ ﮐﻠﻴﺪ ﺳﻤﺖ ﺭﺍﺳﺖ ﻣﻮﺱ ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪ .‬ﮔﺰﻳﻨﻪ‬

‫‪ Sharing‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻣﻨﻮﻱ ﻣﺮﺑﻮﻃﻪ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ﺍﻱ ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‬ ‫ﮐﻪ ﺩﺭ ﺁﻥ ﺍﻣﮑﺎﻥ ﺍﻧﺘﺨﺎﺏ ﭼﻨﺪﻳﻦ ﺁﻳﺘﻢ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ .‬ﻣﻘﺪﺍﺭ ﭘﻴﺶ ﻓﺮﺽ ﺑﺮﺍﻱ ‪Sharing‬‬

‫ﺑﺼﻮﺭﺕ ‪ Not Shared‬ﺍﺳﺖ‪ .‬ﺑﺎ ﺗﻐﻴﻴﺮ ﻣﻘﺪﺍﺭ ﮔﺰﻳﻨﻪ ﻓﻮﻕ ﻭ ﺗﺒﺪﻳﻞ ﺁﻥ ﺑﻪ ‪Shared As‬‬ ‫ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﻓﻴﻠﺪ ﺍﻃﻼﻋﺎﺗﻲ ‪ ، Name Share‬ﻧﺎﻡ ﺩﻟﺨﻮﺍﻩ ﺧﻮﺩ ﺭﺍ ﺑﺮﺍﻱ ﻓﻮﻟﺪﺭ ﺑﻪ ﺍﺷﺘﺮﺍﮎ‬ ‫ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﻣﺸــﺨﺺ ﻧﻤﻮﺩ‪ .‬ﻧﺎﻡ ﻓﻮﻕ ﻣﻲ ﺗــﻮﺍﻧﺪ ﺑﺎ ﻧﺎﻡ ﻭﺍﻗﻌﻲ ﻓﻮﻟﺪﺭ ﮐﺎﻣﻼ" ﻣﺘــﻔﺎﻭﺕ‬ ‫ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺒﻼ" ﮔﺰﻳﻨﻪ ‪ Share-level Access Control‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ‬

‫ﮐﺮﺩﻩ ﺑﺎﺷﻴﺪ ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﻄﺢ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻣﻨﻴﺘﻲ )‪ (Access Type‬ﺭﺍ ﻣﺸﺨﺺ‬

‫ﻭ ﺑﺮﺍﻱ ﺁﻥ ﻳﮏ ﺭﻣﺰ ﻋﺒﻮﺭ ﺭﺍ ﻧﻴﺰ ﻣﺸﺨﺺ ﻧﻤﻮﺩ‪ .‬ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺭﻭﺵ ‪ Read-only‬ﺑﺪﻳﻦ‬ ‫ﻣﻔﻬﻮﻡ ﺍﺳﺖ ﮐﻪ ﻫﺮ ﮐﺎﺭﺑﺮ ﻗﺎﺩﺭ ﺑﻪ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻓﻮﻟﺪﺭ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﻭ ﺻﺮﻓﺎ" ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﻣﺸﺎﻫﺪﻩ ﻭ ﺑﺎﺯﻳﺎﺑﻲ ﻓﺎﻳﻞ ﻫﺎ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻘﺮﺍﺭ ﻓﺎﻳﻞ ﻫﺎﻱ ﺟﺪﻳﺪ‬

‫ﺩﺭ ﻓﻮﻟﺪﺭ ﻭ ﻳﺎ ﺣﺬﻑ ﻭ ﺍﺻﻼﺡ ﻓﺎﻳﻞ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻓﻮﻟﺪﺭ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬ ‫ﺭﻭﺵ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻓﻮﻟﺪﺭ‪ access Full ،‬ﺗﻌﻴﻴﻦ ﮔﺮﺩﺩ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﻗﺎﺩﺭ ﺑﻪ ﻣﺸﺎﻫﺪﻩ‪ ،‬ﻧﻮﺷﺘﻦ‪،‬‬ ‫ﺍﻳﺠﺎﺩ ﻭ ﺣﺬﻑ ﻓﺎﻳﻞ ﺩﺭ ﻓﻮﻟﺪﺭ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺭﻣﺰ ﻋﺒﻮﺭ ﻣﻲ ﺗﻮﺍﻥ‬ ‫ﻫﺮ ﺩﻭ ﮔﺰﻳﻨﻪ ﺭﺍ ﺑﺼﻮﺭﺕ ﺷﻨﺎﻭﺭ ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

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‫ﺍﺷﺘﺮﺍﮎ ﭼﺎﭘﮕﺮ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﺘﺮﺍﮎ ﻳﮏ ﭼﺎﭘﮕﺮ ﺩﺭ ﺍﺑﺘﺪﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺻﺤﺖ ﻋﻤﻠﻴﺎﺕ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺧﺼﻮﺻﺎ"‬

‫ﻓﻌﺎﻝ ﺷﺪﻥ ‪ Sharing File and Printer‬ﺍﻃﻤﻴﻨﺎﻥ ﺣﺎﺻﻞ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﺩﻧﺒـــﺎﻝ‬ ‫ﻧﻤﻮﺩﻥ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﻣﻲ ﺗﻮﺍﻥ ﺑﺮﺍﻱ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ ﻳﮏ ﭼﺎﭘﮕﺮ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺭﺍ ﺩﻧـــﺒﺎﻝ‬ ‫ﻧﻤﻮﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﺍﺯ ﻃﺮﻳﻖ ﺩﮐﻤﻪ ‪ ، Start‬ﮔﺰﻳﻨﻪ ‪ Setting‬ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ‪ Printers‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬ﺩﺭ ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ﺍﻱ ﺷﺎﻣﻞ ﻟﻴﺴﺘﻲ ﺍﺯ ﺗﻤﺎﻡ ﭼﺎﭘﮕﺮﻫﺎﻱ ﻣﺤﻠﻲ ﻧﻤﺎﻳﺶ‬ ‫ﺩﺍﺩﻩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﻣﻮﺱ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﺁﻳﮑﻮﻥ ﭼﺎﭘﮕﺮﻱ ﮐﻪ ﻗﺼﺪ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ ﺁﻥ ﺭﺍ‬

‫ﺩﺍﺭﻳﺪ‪ ،‬ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﻭ ﮐﻠﻴﺪ ﺳﻤﺖ ﺭﺍﺳﺖ ﻣﻮﺱ ﺭﺍ ﻓﻌﺎﻝ ﻭ ﮔﺰﻳﻨﻪ ‪ Sharing‬ﺭﺍ‬

‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﺩﺭ ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ‪ Properties‬ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻓﻴﻠﺪ ﺍﻃﻼﻋﺎﺗﻲ‬

‫‪ Shared As‬ﻧﺎﻡ ﺩﻟﺨﻮﺍﻩ ﺑﺮﺍﻱ ﭼﺎﭘﮕﺮ ) ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻦ( ﺭﺍ ﻣﺸﺨﺺ‬

‫ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺗﻤﺎﻳﻞ ﻳﮏ ﺭﻣﺰ ﻋﺒﻮﺭ ﻧﻴﺰ ﺭﺍ ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﻣﺸﺨﺺ ﻧﻤﻮﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺑﺎ ﻓﻌﺎﻝ ﮐﺮﺩﻥ ﺩﮐﻤﻪ ‪ ،OK‬ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻃﻪ ﺑﺴﺘﻪ ﺷﺪﻩ ﻭ ﭼﺎﭘﮕﺮ ﺑﻪ‬ ‫ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﺍﺳﺖ ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﭼﺎﭘﮕﺮ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﺷﺪﻩ ﺍﺯ ﻃﺮﻳﻖ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺩﻳﮕﺮ ‪ ،‬ﻣﺮﺍﺣﻞ‬ ‫ﺯﻳﺮ ﺭﺍ ﺩﻧﺒﺎﻝ ﻧﻤﺎﺋﻴﺪ‪:‬‬ ‫•‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﭘﻨﺠﺮﻩ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Printer‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﻭﻳﺰﺍﺭﺩ) ﺑﺮﻧﺎﻣﻪ ﮐﻤﮑﻲ ( ‪ Add a Printer‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﮔﺰﻳﻨﻪ ‪ Network Printer‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻭ ﺩﮐﻤﻪ ‪ OK‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﻭﻳﺰﺍﺭﺩ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﺍﺩﺍﻣﻪ ﻟﻴﺴﺘﻲ ﺍﺯ ﭼﺎﭘﮕﺮﻫﺎﻱ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ‬

‫ﺷﺪﻩ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺭﺍ ﻧﻤﺎﻳﺶ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﭼﺎﭘﮕﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ‬

‫ﺍﻧﺘﺨﺎﺏ ﻭ ﺩﮐﻤﻪ ‪ Next‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﻧﻬﺎﻳﺖ ﻭﻳﺰﺍﺭﺩ ﻣﺮﺑﻮﻃﻪ ﺩﺭﺍﻳﻮﺭ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﺭﺍ ﻧﺼﺐ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ) .‬ﺩﺭ ﺑﺮﺧﻲ ﺣﺎﻻﺕ ﻣﻤﮑﻦ ﺍﺳﺖ ﻧﻴﺎﺯ ﺑﻪ ‪ CD‬ﻭ ﻳﺎ ﺩﻳﺴﮑﺖ‬ ‫ﺣﺎﻭﻱ ﺩﺭﺍﻳﻮﺭ ﭼﺎﭘﮕﺮ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ(‬

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‫ﺍﺷﺘﺮﺍﮎ ﺧﻂ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺭﺷﺪ ﺷﺒﮑﻪ ﻫﺎ ﻱ ﮐﻮﭼﮏ‪ ،‬ﺷﺮﮐﺖ ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺍﺯ ﻧﺴﺨﻪ ﻭﻳﻨﺪﻭﺯ‬

‫‪ CE٩٨‬ﺑﻪ ﺑﻌﺪ ﺍﻣﮑﺎﻧﻲ ﺑﺎ ﻧﺎﻡ ‪ (Internet Connection Sharing(ICS‬ﺭﺍ ﺍﺿﺎﻓﻪ‬

‫ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ICS‬ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮑﻲ ﺍﺯ ﺭﻭﺵ‬ ‫ﻫﺎﻱ ﺭﺍﻳﺞ ﻧﻈﻴﺮ‪ :‬ﻣﻮﺩﻡ‪ ISDN ،DSL ،‬ﻭ ﻳﺎ ﮐﺎﺑﻞ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﺍﺳﺖ‪ ،‬ﺑﻪ ﺍﺷﺘﺮﺍﮎ‬ ‫ﮔﺬﺍﺷﺖ‪ .‬ﻭﻳﻨﺪﻭﺯ ‪ CE٩٨‬ﻭ ﺳﺎﻳﺮ ﻧﺴﺨﻪ ﻫﺎﻱ ﻭﻳﻨﺪﻭﺯ ﺩﺍﺭﺍﻱ ﻳﮏ ﻭﻳﺰﺍﺭﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﻓﻌﺎﻝ‬ ‫ﮐﺮﺩﻥ ﺍﻣﮑﺎﻥ ﻓﻮﻕ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻋﻨﺎﺻﺮ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ‪ ICS‬ﺑﺼﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﺑﺮ‬

‫ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻧﺼﺐ ﻧﻤﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺗﻮﺟﻪ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ﮐﻪ ﺍﻣﮑﺎﻥ ﻓﻮﻕ ﺻﺮﻓﺎ" ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮ‬ ‫ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﺍﺳﺖ‪ ،‬ﻓﻌﺎﻝ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺍﻱ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﺍﻣﮑﺎﻥ ﻓﻮﻕ‬ ‫) ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﻧﺴﺨﻪ ﻭﻳﻨﺪﻭﺯ ‪ CE٩٨‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ( ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺮﺍﺣﻞ‬

‫ﺯﻳﺮ ﺭﺍ ﺩﻧﺒﺎﻝ ﮐﺮﺩ‪:‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﺍﺯ ﻃﺮﻳﻖ ‪، Control Panel‬ﮔﺰﻳﻨﻪ‪Programs Add/Remove‬‬

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‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﮔﺰﻳﻨﻪ ‪ windows setup‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺁﻳﺘﻢ ‪Internet‬‬

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‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﻋﻨﺼﺮ ‪ Internet Connection Sharing‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫‪ Tools‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪.‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﮐﻠﻴﺪ ‪ Next‬ﺭﺍ ﻓﻌﺎﻝ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ‪ ICS‬ﭘﻴﮑﺮﺑﻨﺪﻱ ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪،‬‬

‫ﺑﺮﻧﺎﻣﻪ ﮐﻤﮑﻲ ) ﻭﻳﺰﺍﺭﺩ( ﻣﺮﺑﻮﻁ ﺑﻪ ‪ ICS‬ﻓﻌﺎﻝ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﻣﻲ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ‬ ‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﻻﺯﻡ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﭘﺲ ﺍﺯ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﺿﺮﻭﺭﻱ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ‪ ICS‬ﺑﺮ‬ ‫ﺭﻭﻱ ﺁﻥ ﻓﻌﺎﻝ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﻭﻳﺰﺍﺭﺩ ﻣﺮﺑﻮﻃﻪ ﻧﻴﺎﺯ ﺑﻪ ﻳﮏ ﻋﺪﺩ ﺩﻳﺴﮑﺖ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﺩﻳﺴﮑﺖ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺳﺎﻳﺮ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﮐﻪ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺮﻭﻳﺲ ‪ ICS‬ﺭﺍ ﺩﺍﺷﺘﻪ‬

‫ﺑﺎﺷﻨﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫‪269‬‬

‫ﻣﺮﺍﺣﻞ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﺳﺮﻭﻳﺲ ‪ ICS‬ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺍﺯ ﻭﻳﻨﺪﻭﺯ ‪ ٢٠٠٠‬ﻭ ﻳﺎ ‪ XP‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﺑﻤﺮﺍﺗﺐ ﺭﺍﺣﺖ ﺗﺮ ﺍﺯ ﻣﺮﺍﺣﻞ ﮔﻔﺘﻪ ﺷﺪﻩ ﻓﻮﻕ ﺍﺳﺖ ‪.‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﭘﺲ ﺍﺯ ﺍﻳﺠﺎﺩ‬ ‫ﻳﮏ ‪ ، Dial-up‬ﺑﺎ ﺍﻧﺘﺨﺎﺏ ﺁﻥ ﻭ ﻓﻌﺎﻝ ﮐﺮﺩﻥ ﮐﻠﻴﺪ ﺳﻤﺖ ﺭﺍﺳﺖ‪ ،‬ﮔﺰﻳﻨﻪ ‪ Properties‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﭘﻨﺠﺮﻩ ‪ Dial-up Connection properties‬ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ‬

‫ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﺑﺮﺍﻱ ﺍﺷﺘﺮﺍﮎ ﺧﻄﻲ ﺍﺭﺗﺒﺎﻁ ﮔﺰﻳﻨﻪ "‪ "Sharing‬ﺭﺍ ﺍﻧﺘﺨﺎﺏ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﮔﺰﻳﻨﻪ‬ ‫"‪ "Enable internet connection sharing for this connection‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻭ ﺳﺎﻳﺮ ﻣﻮﺍﺭﺩ ﻭ ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﺼﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻫﺎﺏ ﻭ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺁﻥ‬ ‫ﻫﺎﺏ ﺍﺯ ﺟﻤﻠﻪ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﭘﺎﺳﺎﺯﻱ ﺷﺒﮑﻪ‬

‫ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ ‪ .‬ﮔﺮﭼﻪ ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﮐﻪ ﺍﻣﺮﻭﺯﻩ ﺍﻳﺠﺎﺩ ﻣﻲ ﮔﺮﺩﺩ ﺍﺯ‬ ‫ﺳﻮﺋﻴﭻ ﺩﺭ ﻣﻘﺎﺑﻞ ﻫﺎﺏ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻭﻟﻲ ﻣﺎ ﻫﻤﭽﻨﺎﻥ ﺷﺎﻫﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ‬ ‫ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﻣﻲ ﺑﺎﺷﻴﻢ‪ .‬ﻗﺒﻞ ﺍﺯ ﭘﺮﺩﺍﺧﺘﻦ ﺑﻪ ﺍﺻﻞ‬

‫ﻣﻮﺿﻮﻉ‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﺑﺮﺧﻲ ﺗﻌﺎﺭﻳﻒ ﻣﻬﻢ ﮐﻪ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺪﻓﻌﺎﺕ ﺑﻪ ﺁﻧﺎﻥ ﻣﺮﺍﺟﻌﻪ‬ ‫ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ ﺑﻴﺸﺘﺮ ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪.‬‬ ‫•‬

‫‪ : Domain‬ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻋﻀﻮﺀ ﻳﮏ ‪ domain‬ﻫﺮ ﺍﺗﻔﺎﻕ ﻭ ﻳﺎ ﺭﻭﻳﺪﺍﺩﻱ‬

‫•‬

‫‪ : Collision Domain‬ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﻳﮏ ﺗﺼﺎﺩﻡ ) ‪ ( Collision‬ﺑﻴﻦ‬

‫ﺭﺍ ﮐﻪ ﺩﺭ ‪ domain‬ﺍﺗﻔﺎﻕ ﻣﻲ ﺍﻓﺘﺪ‪ ،‬ﻣﺸﺎﻫﺪﻩ ﻭ ﻳﺎ ﺧﻮﺍﻫﻨﺪ ﺷﻨﻴﺪ‪.‬‬

‫ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﺳﺎﻳﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪ domain‬ﺁﻥ ﺭﺍ ﺷﻨﻴﺪﻩ ﻭ ﺁﮔﺎﻫﻲ ﻻﺯﻡ‬ ‫ﺩﺭ ﺧﺼﻮﺹ ﺁﻥ ﭼﻴﺰﻱ ﮐﻪ ﺍﺗﻔﺎﻕ ﺍﻓﺘﺎﺩﻩ ﺍﺳﺖ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ‬ ‫ﻓﻮﻕ ﻋﻀﻮﺀ ﻳﮏ ‪ Collision Domain‬ﻳﮑﺴﺎﻥ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﺋﻲ‬ ‫ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻫﺎﺏ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﺷﻮﻧﺪ‪ ،‬ﻋﻀﻮﺀ ﻳﮏ ‪Collision‬‬

‫‪ Domain‬ﻳﮑﺴﺎﻥ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ ) ﺑﺮ ﺧﻼﻑ ﺳﻮﺋﻴﭻ (‪.‬‬ ‫•‬

‫‪ : Broadcast Domain‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ‪ ،domain‬ﻳﮏ ﭘﻴﺎﻡ ‪broadcast‬‬ ‫) ﻳﮏ ﻓﺮﻳﻢ ﻭ ﻳﺎ ﺩﺍﺩﻩ ﮐﻪ ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ( ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ‪ doamin‬ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺎﺏ ﻭ ﺳﻮﺋﻴﭻ ﺑﺎ ﻣﻮﺿﻮﻉ‬ ‫‪ broadcast domain‬ﺑﺮﺧﻮﺭﺩ ﻣﻨﺎﺳﺒﻲ ﻧﺪﺍﺷﺘﻪ ) ﺍﻳﺠﺎﺩ ﺣﻮﺯﻩ ﻫﺎﻱ ﻣﺠﺰﺍﺀ( ﻭ ﺩﺭ‬ ‫ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺑﻪ ﻳﮏ ﺭﻭﺗﺮ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﺧﻮﺭﺩ ﻣﻨﺎﺳﺐ )ﺍﻳﺠﺎﺩ ﺣﻮﺯﻩ ﻫﺎﻱ ﻣﺠﺰﺍﺀ( ﺑﺎ ‪،collision domain‬‬ ‫‪ broadcast domain‬ﻭ ﺍﻓﺰﺍﻳﺶ ﺳﺮﻋﺖ ﻭ ﮐﺎﺭﺍﺋﻲ ﻳﮏ ﺷﺒﮑﻪ ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ‬

‫ﺍﻓﺰﺍﺭﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎ ‪ collision domain‬ﻣﺠﺰﺍﺋﻲ ﺭﺍ ﺍﻳﺠﺎﺩ‬

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‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﻭﻟﻲ ﺩﺭ ﺧﺼﻮﺹ ‪ broadcast doamin‬ﺑﺪﻳﻦ ﺷﮑﻞ ﺭﻓﺘﺎﺭ ﻧﻤﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺭﻭﺗﺮﻫﺎ‪ broadcast domain ،‬ﻭ ‪ domain collision‬ﻣﺠﺰﺍﺋﻲ ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩﻩ ﻭ‬ ‫ﺩﺭ ﻣﻘﺎﺑﻞ ﻫﺎﺏ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ‪ broadcast doamin‬ﻭ ‪domain Collision‬‬ ‫ﺟﺪﺍﮔﺎﻧﻪ ﻧﻤﻲ ﺑﺎﺷﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻳﮏ ﻧﻤﻮﻧﻪ ﻫﺎﺏ ﻫﺸﺖ ﭘﻮﺭﺕ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‬

‫) ‪.( D-Link DE-808TP 10Mbps Ethernet 8-Port Mini-Hub‬‬

‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﻫﺎﺏ‬

‫ﻫﺎﺏ‪ ،‬ﻳﮑﻲ ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻭ ﺍﺭﺯﺍﻧﺘﺮﻳﻦ ﺭﻭﺵ ﺍﺗﺼﺎﻝ‬

‫ﺩﻭ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺍﺳﺖ‪ .‬ﻫﺎﺏ ﺩﺭ ﺍﻭﻟﻴﻦ ﻻﻳﻪ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻓﻌﺎﻟﻴﺖ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺁﻧﺎﻥ ﻓﺮﻳﻢ ﻫﺎﻱ ﺩﺍﺩﻩ ﺭﺍ ﻧﻤﻲ ﺧﻮﺍﻧﻨﺪ )ﮐﺎﺭﻱ ﮐﻪ ﺳﻮﺋﻴﭻ ﻭ ﻳﺎ ﺭﻭﺗﺮ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ(‬

‫ﻭ ﺻﺮﻓﺎ" ﺍﻳﻦ ﺍﻃﻤﻴﻨﺎﻥ ﺭﺍ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﮐﻪ ﻓﺮﻳﻢ ﻫﺎﻱ ﺩﺍﺩﻩ ﺑﺮ ﺭﻭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ‪،‬‬

‫ﺗﮑﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﮔﺮﻩ ﻫﺎﺋﻲ ﮐﻪ ﻳﮏ ﺍﺗﺮﻧﺖ ﻭ ﻳﺎ ‪ Fast Ethernet‬ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻗﻮﺍﻧﻴﻦ ‪CSMA/CD‬‬

‫ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﻣﻲ ﮔﺬﺍﺭﻧﺪ ‪ ،‬ﻋﻀﻮﺀ ﻳﮏ ‪ Collision Domain‬ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﻳﻦ ﺑﺪﺍﻥ‬ ‫ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ ﺗﻤﺎﻣﻲ ﮔﺮﻩ ﻫﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻫﺎﺏ ﺑﺨﺸﻲ ﺍﺯ ‪Collision domain‬‬ ‫ﻣﺸﺎﺑﻪ ﺑﻮﺩﻩ ﻭ ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ‪ collision‬ﺍﺗﻔﺎﻕ ﻣﻲ ﺍﻓﺘﺪ‪ ،‬ﺳﺎﻳﺮ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ‬ ‫‪ domain‬ﻧﻴﺰ ﺁﻥ ﺭﺍ ﺷﻨﻴﺪﻩ ﻭ ﺍﺯ ﺁﻥ ﻣﺘﺎﺛﺮ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﻳﺎ ﮔﺮﻩ ﻫﺎﻱ ﻣﺘﺼﻞ‬

‫ﺷﺪﻩ ﺑﻪ ﻫﺎﺏ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ ، Unshielded Twisted Pair) UTP‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺻﺮﻓﺎ" ﻳﮏ ﮔﺮﻩ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﻫﺮ ﭘﻮﺭﺕ ﻫﺎﺏ ﻣﺘﺼﻞ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ" ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬ ‫ﻳﮏ ﻫﺎﺏ ﻫﺸﺖ ﭘﻮﺭﺕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﻫﺸﺖ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ‬

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‫ﻫﺎﺏ ﻫﺎ ﺑﻪ ﻣﺘﺪﺍﻭﻟﻲ ﺍﻣﺮﻭﺯ ﻧﺒﻮﺩﻧﺪ ﻭ ﻗﻴﻤﺖ ﺁﻧﺎﻥ ﻧﻴﺰ ﮔﺮﺍﻥ ﺑﻮﺩ‪ ،‬ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﻧﺼﺐ‬ ‫ﺷﺪﻩ ﺩﺭ ﺍﺩﺍﺭﺍﺕ ﻭ ﻳﺎ ﻣﻨﺎﺯﻝ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﻮﺍﮐﺴﻴﺎﻝ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻳﺪ‪.‬‬

‫ﻧﺤﻮﻩ ﮐﺎﺭ ﻫﺎﺏ ﺑﺴﻴﺎﺭ ﺳﺎﺩﻩ ﺍﺳﺖ‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮑﻲ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻫﺎﺏ ﺍﻗﺪﺍﻡ‬ ‫ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺋﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﺎﻳﺮ ﭘﻮﺭﺕ ﻫﺎﻱ ﻫﺎﺏ ﻧﻴﺰ ﺁﻥ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ )ﺩﺍﺩﻩ‬ ‫ﺍﺭﺳﺎﻟﻲ ﺗﮑﺮﺍﺭ ﻭ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﭘﻮﺭﺕ ﻫﺎﻱ ﻫﺎﺏ ﻧﻴﺰ ﻓﺮﺳﺘﺎﺩﻩ ﻣﻲ ﺷﻮﺩ(‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ‬ ‫ﻋﻤﻠﮑﺮﺩ ﻫﺎﺏ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﮔﺮﻩ ﻳﮏ ﺩﺍﺩﻩ ﺋﻲ ﺭﺍ ﺑﺮﺍﻱ ﮔﺮﻩ ﺷﺶ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﺗﻤﺎﻣﻲ ﮔﺮﻩ ﻫﺎﻱ ﺩﻳﮕﺮ ﻧﻴﺰ ﺩﺍﺩﻩ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‪،‬‬

‫ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺩﺍﺩﻩ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ ﺍﻧﺠﺎﻡ ﻭ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬ ‫ﺗﺸﺨﻴﺺ ﺩﺍﺩﻩ ﺷﻮﺩ ﮐﻪ ﺩﺍﺩﻩ ﺍﺭﺳﺎﻟﻲ ﻣﺘﻌﻠﻖ ﺑﻪ ﺁﻧﺎﻥ ﻧﻴﺴﺖ‪ ،‬ﺁﻥ ﺭﺍ ﻧﺎﺩﻳﺪﻩ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪.‬‬ ‫ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮐﻪ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻘﺼﺪ‬

‫ﻓﺮﻳﻢ ﺍﺭﺳﺎﻟﻲ ﺭﺍ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﻧﺠﺎﻡ ﻣﻲ ﺷﻮﺩ‪ .‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺭﺍ ﺍﻧﺠﺎﻡ ﻭ ﺩﺭ‬ ‫ﺻﻮﺭﺕ ﻋﺪﻡ ﻣﻄﺎﺑﻘﺖ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻮﺟﻮﺩ ﺩﺭ ﻓﺮﻳﻢ ‪ ،‬ﺑﺎ ﺁﺩﺭﺱ ‪ MAC‬ﮐﺎﺭﺕ ﺷﺒﮑﻪ‪ ،‬ﻓﺮﻳﻢ‬ ‫ﺍﺭﺳﺎﻟﻲ ﺩﻭﺭ ﺍﻧﺪﺍﺧﺘﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺍﮐﺜﺮ ﻫﺎﺏ ﻫﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﭘﻮﺭﺕ ﺧﺎﺹ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﺻﻮﺭﺕ ﻳﮏ ﭘﻮﺭﺕ‬

‫ﻣﻌﻤﻮﻟﻲ ﻭ ﻳﺎ ﻳﮏ ﭘﻮﺭﺕ ‪ uplink‬ﺭﻓﺘﺎﺭ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﭘﻮﺭﺕ ‪ uplink‬ﻣﻲ ﺗﻮﺍﻥ‬ ‫ﻳﮏ ﻫﺎﺏ ﺩﻳﮕﺮ ﺭﺍ ﺑﻪ ﻫﺎﺏ ﻣﻮﺟﻮﺩ‪ ،‬ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺗﻌﺪﺍﺩ ﭘﻮﺭﺕ ﻫﺎ ﺍﻓﺰﺍﻳﺶ‬

‫ﻳﺎﻓﺘﻪ ﻭ ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﺗﻌﺪﺍﺩ ﺑﻴﺸﺘﺮﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺷﺒﮑﻪ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺭﻭﺵ ﻓﻮﻕ ﮔﺰﻳﻨﻪ ﺍﻱ ﺍﺭﺯﺍﻥ ﻗﻴﻤﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮔﺮﻩ ﻫﺎ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ ﻭﻟﻲ‬

‫ﺑﺎ ﺍﻧﺠﺎﻡ ﺍﻳﻦ ﮐﺎﺭ ﺷﺒﮑﻪ ﺷﻠﻮﻍ ﺗﺮ ﺷﺪﻩ ﻭ ﻫﻤﻮﺍﺭﻩ ﺑﺮ ﺭﻭﻱ ﺁﻥ ﺣﺠﻢ ﺑﺎﻻﺋﻲ ﺩﺍﺩﻩ ﻏﻴﺮ ﺿﺮﻭﺭﻱ‬

‫ﺩﺭ ﺣﺎﻝ ﺟﺎﺑﺠﺎﺋﻲ ﺍﺳﺖ‪ .‬ﺗﻤﺎﻣﻲ ﮔﺮﻩ ﻫﺎ‪ ،‬ﻋﻀﻮﺀ ﻳﮏ ‪ Broadcast domain‬ﻭ‬ ‫‪ collision domain‬ﻳﮑﺴﺎﻧﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺗﻤﺎﻣﻲ ﺁﻧﺎﻥ ﻫﺮ ﻧﻮﻉ ‪ collision‬ﻭ ﻳﺎ‬

‫‪ Broadcast‬ﺭﺍ ﮐﻪ ﺍﺗﻔﺎﻕ ﺧﻮﺍﻫﺪ ﺍﻓﺘﺎﺩ ‪ ،‬ﻣﻲ ﺷﻨﻮﻧﺪ‪.‬‬

‫ﺩﺭ ﺍﮐﺜﺮ ﻫﺎﺏ ﻫﺎ ﺍﺯ ﻳﮏ ‪ LED‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺸﺎﻥ ﺩﺍﺩﻥ ﻓﻌﺎﻝ ﺑﻮﺩﻥ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﺷﺪﻩ ﺑﻴﻦ‬ ‫ﻫﺎﺏ ﻭ ﮔﺮﻩ ﻭ ﺍﺯ ‪ LED‬ﺩﻳﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺸﺎﻥ ﺩﺍﺩﻥ ﺑﺮﻭﺯ ﻳﮏ ‪ ، collision‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ ) .‬ﺩﻭ ‪ LED‬ﻣﺠﺰﺍﺀ ( ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﺍﺯ ﻫﺎﺏ ﻫﺎ ﺩﻭ ‪ LED‬ﻣﺮﺑﻮﻁ ﺑﻪ ﻓﻌﺎﻝ ﺑﻮﺩﻥ‬

‫ﻟﻴﻨﮏ ﺍﺭﺗﺒﺎﻃﻲ ﺑﻴﻦ ﻫﺎﺏ ﻭ ﮔﺮﻩ ﻭ ﻓﻌﺎﻟﻴﺖ ﭘﻮﺭﺕ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺗﺮﮐﻴﺐ ﻭ ﺯﻣﺎﻧﻲ ﮐﻪ ﭘﻮﺭﺕ ﺩﺭ‬ ‫ﺣﺎﻝ ﻓﻌﺎﻟﻴﺖ ﺍﺳﺖ ‪ LED ،‬ﻣﺮﺑﻮﻃﻪ ﭼﺸﻤﮏ ﺯﻥ ﺷﺪﻩ ﻭ ﺯﻣﺎﻧﻲ ﮐﻪ ﻓﻌﺎﻟﻴﺘﻲ ﺍﻧﺠﺎﻡ ﻧﻤﻲ ﺷﻮﺩ‪،‬‬ ‫‪ LED‬ﻓﻮﻕ ﺑﻪ ﺻﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﺭﻭﺷﻦ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫‪ LED‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Collision‬ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻫﺎﺏ ﻫﺎ ﺯﻣﺎﻧﻲ ﺭﻭﺷﻦ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﻳﮏ‬ ‫‪ collision‬ﺑﻮﺟﻮﺩ ﺁﻳﺪ‪ Collision .‬ﺯﻣﺎﻧﻲ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻳﺪ ﮐﻪ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﮔﺮﻩ‬ ‫ﺳﻌﻲ ﻧﻤﺎﻳﻨﺪ ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺻﺤﺒﺖ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﭘﺲ ﺍﺯ ﺑﺮﻭﺯ ﻳﮏ ‪، Collision‬‬

‫ﻓﺮﻳﻢ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺑﺮﺧﻮﺭﺩ ﻧﻤﻮﺩﻩ ﻭ ﺧﺮﺍﺏ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻫﺎﺏ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺸﺨﻴﺺ ﺍﻳﻦ ﻧﻮﻉ ﺗﺼﺎﺩﻡ ﻫﺎ ﺑﻪ ﺍﻧﺪﺍﺯﻩ ﮐﺎﻓﻲ ﻫﻮﺷﻤﻨﺪ ﺑﻮﺩﻩ ﻭ ﺑﺮﺍﻱ ﻣﺪﺕ‬

‫ﺯﻣﺎﻥ ﮐﻮﺗﺎﻫﻲ ﭼﺮﺍﻍ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ collision‬ﺭﻭﺷﻦ ﻣﻲ ﮔﺮﺩﺩ‪ ) .‬ﻳﮏ ﺩﻫﻢ ﺛﺎﻧﻴﻪ ﺑﻪ ﺍﺯﺍﻱ ﻫﺮ‬ ‫ﺗﺼﺎﺩﻡ (‪.‬‬

‫ﺗﻌﺪﺍﺩ ﺍﻧﺪﮐﻲ ﺍﺯ ﻫﺎﺏ ﻫﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﺍﺗﺼﺎﻝ ﺧﺎﺹ ﺍﺯ ﻧﻮﻉ ‪ BNC‬ﺑﻮﺩﻩ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺁﻥ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﻳﮏ ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻝ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺍﺗﺼﺎﻝ ﻓﻮﻕ‪ LED ،‬ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫ﺍﺗﺼﺎﻝ ‪ BNC‬ﺭﻭﻱ ﻫﺎﺏ ﺭﻭﺷﻦ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺳﻮﺋﻴﭻ‬ ‫ﺷﺒﮑﻪ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ) ﮔﺮﻩ ( ﮐﻪ ﺗﻮﺳﻂ ﻳﮏ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ) ﮐﺎﺑﻠﻲ ﺑﺪﻭﻥ‬

‫ﮐﺎﺑﻞ( ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﺧﺎﺻﻲ ﻧﻈﻴﺮ‬ ‫ﻫﺎﺏ ﻭ ﺭﻭﺗﺮ ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻳﮑﻲ ﺍﺯ ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﻭ ﻣﻬﻢ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ‪ ،‬ﭼﻨﺪﻳﻦ ﮐﺎﺭﺑﺮﻗﺎﺩﺭﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ‬

‫ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﺑﺮ ﺳﺮﻋﺖ ﺩﺳﺘﻴﺎﺑﻲ‬

‫ﺳﺎﻳﺮ ﮐﺎﺭﺑﺮﺍﻥ ﺷﺒﮑﻪ ﺗﺎﺛﻴﺮ ﻧﺨﻮﺍﻫﺪ ﮔﺬﺍﺷﺖ‪ .‬ﺳﻮﺋﻴﭻ ﻫﻤﺎﻧﻨﺪ ﺭﻭﺗﺮ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ‬ ‫ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﮔﺮﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ) ﻣﻌﻤﻮﻻ" ﮐﺎﻣﭙﻴﻮﺗﺮ( ﻳﮏ‬

‫ﺷﺒﮑﻪ ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺷﺒﮑﻪ ﻫﺎ ﻭ ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺍﺭﺍﻱ ﺍﻧﻮﺍﻉ ﻣﺘﻔﺎﻭﺗﻲ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ ..‬ﺳﻮﺋﻴﭻ ﻫﺎﺋﻲ ﮐﻪ ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺍﺗﺼﺎﻻﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ LAN‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺳﻮﺋﻴﭻ ﻫﺎ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ‬ ‫ﺍﺭﺗﺒﺎﻃﺎﺕ ﺷﺒﮑﻪ ﺭﺍ ﺑﻴﻦ ﺻﺮﻓﺎ" ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﮐﻪ ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺭﺍ ﺩﺍﺭﻧﺪ‪ ،‬ﺩﺭ ﺯﻣﺎﻥ‬

‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﻣﺒﺎﻧﻲ ﺷﺒﮑﻪ‬

‫ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺸﺮﺡ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫ﺷﺒﮑﻪ ‪ .‬ﺷﺒﮑﻪ ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ )ﺑﺎ ﻳﮏ ﺭﻭﺵ ﺧﺎﺹ(‪،‬‬

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‫ﮔﺮﻩ ‪ .‬ﮔﺮﻩ ‪ ،‬ﺷﺎﻣﻞ ﻫﺮ ﭼﻴﺰﻱ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ ).‬ﮐﺎﻣﭙﻴﻮﺗﺮ‪،‬‬

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‫ﺳﮕﻤﻨﺖ‪ .‬ﺳﮕﻤﻨﺖ ﻳﮏ ﺑﺨﺶ ﺧﺎﺹ ﺍﺯ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﻳﮏ ﺳﻮﺋﻴﭻ‪ ،‬ﺭﻭﺗﺮ ﻭ‬

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‫ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ‪ .‬ﮐﺎﺑﻞ ﺍﺻﻠﻲ ﮐﻪ ﺗﻤﺎﻡ ﺳﮕﻤﻨﺖ ﻫﺎ ﺑﻪ ﺁﻥ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻣﻌﻤﻮﻻ"‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺒﺎﺩﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ‪.‬‬ ‫ﭼﺎﭘﮕﺮ ﻭ ‪( ...‬‬

‫ﻳﺎ ‪ Bridge‬ﺍﺯ ﺳﺎﻳﺮ ﺑﺨﺶ ﻫﺎ ﺟﺪﺍ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﻳﮏ ﺷﺒﮑﻪ ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﻱ ﻧﺴﺒﺖ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫‪275‬‬

‫ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﺷﺒﮑﻪ ﺍﺳﺖ ‪ .‬ﻣﺜﻼ" ﻣﻤﮑﻦ ﺍﺳﺖ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ‬ ‫ﺷﺒﮑﻪ ‪ ١٠٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﻮﺩﻩ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻫﺮ ﺳﮕﻤﻨﺖ‬ ‫‪ ١٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﺎﺷﺪ‪.‬‬ ‫•‬ ‫•‬

‫ﺗﻮﭘﻮﻟﻮﮊﻱ ‪ .‬ﺭﻭﺷﻲ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ ﺭﺍ ﮔﻮﻳﻨﺪ‪.‬‬

‫ﮐﺎﺭﺕ ﺷﺒﮑﻪ ‪ .‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪.‬ﺩﺭ‬

‫ﺍﮐﺜﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺨﺼﻲ‪ ،‬ﮐﺎﺭﺕ ﻓﻮﻕ ﺍﺯ ﻧﻮﻉ ﺍﺗﺮﻧﺖ ﺑﻮﺩﻩ ) ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ‪ ١٠‬ﻭ ﻳﺎ‬ ‫‪ ١٠٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ( ﻭ ﺩﺭ ﻳﮑﻲ ﺍﺯ ﺍﺳﻼﺕ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺭﻭﻱ ﺑﺮﺩ ﺍﺻﻠﻲ ﺳﻴﺴﺘﻢ‪،‬‬

‫ﻧﺼﺐ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﺁﺩﺭﺱ ‪ . MAC‬ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﻫﺮ ﺩﺳﺘﮕﺎﻩ ) ﮐﺎﺭﺕ ﺷﺒﮑﻪ ( ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﺁﺩﺭﺱ‬ ‫ﻓﻮﻕ ﻳﮏ ﻋﺪﺩ ﺷﺶ ﺑﺎﻳﺘﻲ ﺑﻮﺩﻩ ﮐﻪ ﺳﻪ ﺑﺎﻳﺖ ﺍﻭﻝ ﺁﻥ ﻣﺸﺨﺺ ﮐﻨﻨﺪﻩ ﺳﺎﺯﻧﺪﻩ ﮐﺎﺭﺕ‬ ‫ﺷﺒﮑﻪ ﻭ ﺳﻪ ﺑﺎﻳﺖ ﺩﻭﻡ ‪ ،‬ﺷﻤﺎﺭﻩ ﺳﺮﻳﺎﻝ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬

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‫‪ . Unicast‬ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﻳﮏ ﮔﺮﻩ ﺑﺎ ﺁﺩﺭﺱ ﺧﺎﺹ ﻭ ﺩﺭﻳﺎﻓﺖ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﮔﺮﻩ ﺩﻳﮕﺮ ﺍﺳﺖ‪.‬‬

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‫‪ . Multicast‬ﻳﮏ ﮔﺮﻩ‪ ،‬ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﻳﮏ ﮔﺮﻭﻩ ﺧﺎﺹ )ﺑﺎ ﺁﺩﺭﺱ ﻣﺸﺨﺺ(‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪.‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﮔﺮﻭﻩ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻟﻲ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ‬ ‫ﮐﺮﺩ‪.‬‬

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‫‪ . Broadcast‬ﻳﮏ ﮔﺮﻩ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﺗﻤﺎﻡ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ‬

‫ﺩﺭ ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺘﺪﺍﻭﻝ ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﮔﺮﻩ ﻫﺎ ﺍﺯ ﻫﺎﺏ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ‬

‫ﺭﺷﺪ ﺷﺒﮑﻪ ) ﺗﻌﺪﺍﺩ ﮐﺎﺭﺑﺮﺍﻥ ‪ ،‬ﺗﻨﻮﻉ ﻧﻴﺎﺯﻫﺎ‪ ،‬ﮐﺎﺭﺑﺮﺩﻫﺎﻱ ﺟﺪﻳﺪ ﺷﺒﮑﻪ ﻭ ‪ (...‬ﻣﺸﮑﻼﺗﻲ ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻳﺪ‪:‬‬

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‫‪ . Scalability‬ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﻫﺎﺏ ‪ ،‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺼﻮﺭﺕ ﻣﺸﺘﺮﮎ‬

‫ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺤﺪﻭﺩ ﺑﻮﺩﻥ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ‪ ،‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ‬ ‫ﺗﻮﺳﻌﻪ‪ ،‬ﮐﺎﺭﺁﺋﻲ ﺷﺒﮑﻪ ﺑﺸﺪﺕ ﺗﺤﺖ ﺗﺎﺛﻴﺮ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﮐﻪ ﺍﻣﺮﻭﺯﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺟﺮﺍﺀ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺷﺒﮑﻪ‪ ،‬ﻃﺮﺍﺣﻲ ﻣﻲ ﮔﺮﺩﻧﻨﺪ ﺑﻪ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‬

‫ﻣﻨﺎﺳﺒﻲ ﻧﻴﺎﺯ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ ‪ .‬ﻋﺪﻡ ﺗﺎﻣﻴﻦ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻮﺭﺩ ﻧﻴﺎﺯﺑﺮﻧﺎﻣﻪ ﻫﺎ‪ ،‬ﺗﺎﺛﻴﺮ ﻣﻨﻔﻲ‬ ‫ﺩﺭ ﻋﻤﻠﮑﺮﺩ ﺁﻧﻬﺎ ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫•‬

‫‪ . Latency‬ﺑﻪ ﻣﺪﺕ ﺯﻣﺎﻧﻲ ﮐﻪ ﻃﻮﻝ ﺧﻮﺍﻫﺪ ﮐﺸﻴﺪ ﺗﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﺑﺮﺳﺪ‪ ،‬ﺍﻃﻼﻕ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﻫﺮ ﮔﺮﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﻣﺒﺘﻨﻲ ﺑﺮ ﻫﺎﺏ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺪﺕ ﺯﻣﺎﻧﻲ ﺭﺍ ﺩﺭ ﺍﻧﺘﻈﺎﺭ ﺳﭙﺮﻱ ﮐﺮﺩﻩ )ﻣﻤﺎﻧﻌﺖ ﺍﺯ ﺗﺼﺎﺩﻡ‬ ‫ﺍﻃﻼﻋﺎﺕ(‪ ،‬ﺑﻤﻮﺍﺯﺍﺕ ﺍﻓﺰﺍﻳﺶ ﺗﻌﺪﺍﺩ ﮔﺮﻩ ﻫﺎ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﻣﺪﺕ ﺯﻣﺎﻥ ﻓﻮﻕ ﺍﻓﺰﺍﻳﺶ‬ ‫ﺧﻮﺍﻫﺪ ﻳﺎﻓﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮑﻲ ﺍﺯ ﮐﺎﺭﺑﺮﺍﻥ ﻓﺎﻳﻞ ﺑﺎ ﻇﺮﻓﻴﺖ‬

‫ﺑﺎﻻﺋﻲ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﺭﺑﺮ ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪ ،‬ﺗﻤﺎﻡ ﮐﺎﺭﺑﺮﺍﻥ ﺩﻳﮕﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﻧﺘﻈﺎﺯ‬ ‫ﺁﺯﺍﺩ ﺷﺪﻥ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺎﺷﻨﺪ‪ .‬ﺑﻬﺮﺣﺎﻝ ﺍﻓﺰﺍﻳﺶ ﻣﺪﺕ‬

‫ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ ﺧﻮﺩ ﺑﺮﺳﺪ‪ ،‬ﻫﺮﮔﺰ ﻣﻮﺭﺩ ﻧﻈﺮ ﮐﺎﺭﺑﺮﺍﻥ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

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‫‪ . Failure Network‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﻫﺎﺏ‪ ،‬ﻳﮑﻲ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ‬ ‫ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻫﺎﺏ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﺠﺎﺩ ﻣﺴﺎﺋﻞ ﻭ ﻣﺸﮑﻼﺗﻲ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻋﺎﻣﻞ ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ ﻣﻲ ﺗﻮﺍﻧﺪ ﻋﺪﻡ ﺗﻨﻈﻴﻢ ﻣﻨﺎﺳﺐ‬ ‫ﺳﺮﻋﺖ )ﻣﺜﻼ" ﺗﻨﻈﻴﻢ ﺳﺮﻋﺖ ﻳﮏ ﻫﺎﺏ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ‪ ١٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﻪ ‪١٠٠‬‬ ‫ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ( ﻭ ﻳﺎ ﺍﺭﺳﺎﻝ ﺑﻴﺶ ﺍﺯ ﺣﺪ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ‬ ‫‪ ، Broadcast‬ﺑﺎﺷﺪ‪.‬‬

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‫‪ . Collisions‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺍﺗﺮﻧﺖ ﺍﺯ ﻓﺮﺁﻳﻨﺪﻩ ﺧﺎﺻﻲ ﺑﺎ‬ ‫ﻧﺎﻡ ‪ CSMA/CD‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﻧﺤﻮﻩ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﻗﺎﻧﻮﻧﻤﻨﺪ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫‪277‬‬

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‫ﺩﺭ ﭼﻨﻴﻦ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺗﺎ ﺯﻣﺎﻧﻴﮑﻪ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺗﺮﺍﻓﻴﮏ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎﺷﺪ‪ ،‬ﮔﺮﻩ‬ ‫ﺍﻱ ﺩﻳﮕﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﻭ ﮔﺮﻩ ﺩﺭ ﻳﮏ‬

‫ﻟﺤﻈﻪ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻳﮏ ﺗﺼﺎﺩﻡ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻳﺠﺎﺩ ﻭ ﻋﻤﻼ" ﺑﺴﺘﻪ‬ ‫ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ ﻧﻴﺰ ﺍﺯ ﺑﻴﻦ ﺧﻮﺍﻫﻨﺪ ﺭﻓﺖ‪ .‬ﻫﺮ ﻳﮏ‬

‫ﺍﺯ ﮔﺮﻩ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ) ﺗﺼﺎﺩﻡ ﮐﻨﻨﺪﻩ ( ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻤﺪﺕ ﺯﻣﺎﻥ ﮐﺎﻣﻼ" ﺗﺼﺎﺩﻓﻲ ﺩﺭ‬ ‫ﺍﻧﺘﻈﺎﺭ ﺑﺎﻗﻲ ﻣﺎﻧﺪﻩ ﻭ ﭘﺲ ﺍﺯ ﻓﺮﺍﻫﻢ ﺷﺪﻥ ﺷﺮﺍﻳﻂ ﺍﺭﺳﺎﻝ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻫﺎﺏ ﻣﺴﻴﺮ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﻳﮏ ﮔﺮﻩ ﺑﻪ ﮔﺮﻩ ﺩﻳﮕﺮ ﺭﺍ ﺑﻪ ﺣﺪﺍﻗﻞ ﻣﻘﺪﺍﺭ ﺧﻮﺩ‬ ‫ﻣﻲ ﺭﺳﺎﻧﺪ ﻭﻟﻲ ﻋﻤﻼ" ﺷﺒﮑﻪ ﺭﺍ ﺑﻪ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﮔﺴﺴﺘﻪ ﺗﻘﺴﻴﻢ ﻧﻤﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﻮﺋﻴﭻ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺗﺤﻘﻖ ﺧﻮﺍﺳﺘﻪ ﻓﻮﻕ ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﺗﻔﺎﻭﺕ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﻴﻦ‬

‫ﻫﺎﺏ ﻭ ﺳﻮﺋﻴﭻ‪ ،‬ﺗﻔﺴﻴﺮ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺍﺳﺖ‪ .‬ﺗﻤﺎﻡ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﻫﺎﺏ‪،‬‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻮﺟﻮﺩ ﺭﺍ ﺑﻴﻦ ﺧﻮﺩ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﻣﻲ ﮔﺬﺍﺭﻧﺪ‪.‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﻣﺘﺼﻞ‬ ‫ﺷﺪﻩ ﺑﻪ ﺳﻮﺋﻴﭻ‪ ،‬ﺩﺍﺭﺍﻱ ﺗﻤﺎﻡ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﺨﺘﺺ ﺧﻮﺩ ﺍﺳﺖ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﻩ ﮔﺮﻩ‬

‫ﺑﻪ ﻫﺎﺏ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﺎﺷﻨﺪ‪ ) ،‬ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭﺛﺎﻧﻴﻪ( ﻫﺮ ﮔﺮﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﺑﺨﺸﻲ ﺍﺯ ﺗﻤﺎﻡ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻮﺟﻮﺩ ) ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ﺭﺍ ﺍﺷﻐﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ) .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺎﻳﺮﮔﺮﻩ ﻫﺎ ﻧﻴﺰ ﻗﺼﺪ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ(‪ .‬ﺩﺭ ﺳﻮﺋﻴﭻ‪ ،‬ﻫﺮﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ‬ ‫ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮﮔﺮﻩ ﻫﺎ ﺑﺎ ﺳﺮﻋﺖ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ‪ ،‬ﺑﺮﺍﻱ ﻫﺮ ﮔﺮﻩ ﻳﮏ ﺳﮕﻤﻨﺖ ﺍﺧﺘﺼﺎﺻﻲ ﺍﻳﺠﺎﺩ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻓﻮﻕ ﺑﻪ ﻳﮏ ﺳﻮﺋﻴﭻ ﻣﺘﺼﻞ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺩﺭ ﺣﻘﻴﻘﺖ ﺳﻮﺋﻴﭻ ﺍﻣﮑﺎﻥ ﺣﻤﺎﻳﺖ ﺍﺯ‬

‫ﭼﻨﺪﻳﻦ ) ﺩﺭ ﺑﺮﺧﻲ ﺣﺎﻻﺕ ﺻﺪﻫﺎ ( ﺳﮕﻤﻨﺖ ﺍﺧﺘﺼﺎﺻﻲ ﺭﺍ ﺩﺍﺭﺍ ﺍﺳﺖ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ‬ ‫ﺗﻨﻬﺎ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺮ ﺳﮕﻤﻨﺖ ﺳﻮﺋﻴﭻ ﮔﺮﻭﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺳﻮﺋﻴﭻ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺘﺨﺎﺏ‬ ‫ﺍﻃﻼﻋﺎﺕ‪ ،‬ﻗﺒﻞ ﺍﺯ ﺭﺳﻴﺪﻥ ﺑﻪ ﺳﺎﻳﺮ ﮔﺮﻩ ﻫﺎ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﻮﺋﻴﭻ‪ ،‬ﻓﺮﻳﻢ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﺭﺍ ﺑﻪ ﺳﮕﻤﻨﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﻫﺪﺍﻳﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﻫﺮ ﺳﮕﻤﻨﺖ ﺩﺍﺭﺍﻱ ﺻﺮﻓﺎ"‬

‫ﻳﮏ ﮔﺮﻩ ﻣﻲ ﺑﺎﺷﺪ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬ ‫‪278‬‬

‫ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ ﺍﻣﮑﺎﻥ ﭼﻨﺪﻳﻦ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺼﻮﺭﺕ‬

‫ﻫﻤﺰﻣﺎﻥ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪.‬‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ‪ ،‬ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺑﺼﻮﺭﺕ ‪ full-duplex‬ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻗﺒﻞ ﺍﺯ‬ ‫ﻣﻄﺮﺡ ﺷﺪﻥ ﺳﻮﺋﻴﭻ‪ ،‬ﺍﺗﺮﻧﺖ ﺑﺼﻮﺭﺕ ‪ half-duplex‬ﺑﻮﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺩﺍﺩﻩ ﻫﺎ ﺩﺭ ﻫﺮ‬ ‫ﻟﺤﻈﻪ ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﺩﺭ ﻳﮏ ﺟﻬﺖ ﺭﺍ ﺩﺍﺭﺍ ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ‪ ،‬ﻫﺮ‬

‫ﮔﺮﻩ ﺻﺮﻓﺎ" ﺑﺎ ﺳﻮﺋﻴﭻ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﮔﺮﻩ ﻫﺎ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ‬ ‫ﻧﻤﻲ ﻧﻤﺎﻳﻨﺪ(‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺍﻃﻼﻋﺎﺕ ﺍﺯ ﮔﺮﻩ ﺑﻪ ﺳﻮﺋﻴﭻ ﻭ ﺍﺯ ﺳﻮﺋﻴﭻ ﺑﻪ ﮔﺮﻩ ﻣﻘﺼﺪ‬ ‫ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﻣﻨﺘﻘﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﻭ ﻳﺎ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬ ‫ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺑﺮﺍﻱ‬

‫ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺋﻴﭻ‪ ،‬ﺷﺒﮑﻪ ﺍﻱ ﻋﺎﺭﻱ ﺍﺯ ﺗﺼﺎﺩﻡ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﻮﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺁﻣﺪ‪ .‬ﺍﻧﺘﻘﺎﻝ ﺩﻭ ﺳﻮﻳﻪ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋــﻴﭻ ‪،‬‬ ‫ﺳﺮﻋﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﻓﺰﺍﻳﺶ ﻣﻲ ﻳﺎﺑﺪ‪.‬‬

‫ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ ﺑﺪﻟﻴﻞ ﻗﻴﻤﺖ ﺑﺎﻻﻱ ﺳﻮﺋﻴﭻ ‪ ،‬ﺻﺮﻓﺎ" ﺍﺯ ﺳﻮﺋﻴﭻ ﺑﻪ ﺗﻨﻬﺎﺋﻲ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ ﺗﺮﮐﻴﺐ ﻫﺎﺏ ﻭ ﺳﻮﺋﻴﭻ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ"‬ ‫ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﻣﻲ ﺗﻮﺍﻧﺪ ﺍﺯ ﭼﻨﺪﻳﻦ ﻫﺎﺏ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﺩﭘﺎﺭﺗﻤﺎﻧﻬﺎﻱ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺳﻮﺋﻴﭻ ﺗﻤﺎﻡ ﻫﺎﺏ ﻫﺎ)ﻣﺮﺑﻮﻁ ﺑﻪ ﻫﺮ‬

‫ﻳﮏ ﺍﺯ ﺩﭘﺎﺭﺗﻤﺎﻧﻬﺎ( ﺑﻴﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﺳﻮﺋﻴﭻ ﻫﺎ‬

‫ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺍﺭﺍﻱ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻐﻴﻴﺮ ﺭﻭﺵ ﺍﺭﺗﺒﺎﻁ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻩ ﻫﺎ‬

‫ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺗﻔﺎﻭﺕ ﺳﻮﺋﻴﭻ ﺑﺎ ﺭﻭﺗﺮ ﭼﻴﺴﺖ؟ ﺳﻮﺋﻴﭻ ﻫﺎ ﻣﻌﻤﻮﻻ" ﺩﺭ ﻻﻳﻪ ﺩﻭﻡ‬

‫)‪ (Data layer‬ﻣﺪﻝ ‪ OSI‬ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ‬ ‫‪ ) MAC‬ﺁﺩﺭﺱ ﻫﺎ ﻱ ﻓﻴﺰﻳﮑﻲ ( ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ .‬ﺭﻭﺗﺮ ﺩﺭ ﻻﻳﻪ ﺳﻮﻡ )‪ (Network‬ﻣﺪﻝ ‪OSI‬‬ ‫‪279‬‬

‫ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﻻﻳﻪ ﻓﻮﻕ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﺭ ‪ IPX‬ﻭ ﻳﺎ ‪ Appeltalk‬ﺍﺳﺘــﻔﺎﺩﻩ‬

‫ﻣﻲ ﺷﻮﺩ‪ ) .‬ﺁﺩﺭﺱ ﻫﺎ ﻱ ﻣﻨﻄﻘﻲ (‪ .‬ﺍﻟﮕﻮﺭﻳﺘﻢ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺨﺎﺫ‬ ‫ﺗﺼﻤﻴﻢ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﻘﺼﺪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺎ ﺍﻟﮕﻮﺭﻳﺘﻢ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺗﻮﺳﻂ ﺭﻭﺗﺮ‪،‬‬ ‫ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪.‬‬

‫ﻳﮑﻲ ﺍﺯ ﻣﻮﺍﺭﺩ ﺍﺧﺘﻼﻑ ﺍﻟﮕﻮﺭﻳﺘﻢ ﻫﺎﻱ ﺳﻮﺋﻴﭻ ﻭ ﻫﺎﺏ‪ ،‬ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ﺁﻧﺎﻥ ﺑﺎ‬

‫‪ Broadcast‬ﺍﺳﺖ ‪ .‬ﻣﻔﻬﻮﻡ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺩﺭ ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﻫﺎ‬ ‫ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ‪ ،‬ﺩﺳﺘﮕﺎﻫﻲ ﻧﻴﺎﺯ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺍﺷﺘﻪ ﻭﻟﻲ ﻧﻤﻲ ﺩﺍﻧﺪ‬ ‫ﮐﻪ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺮﺍﻱ ﭼﻪ ﮐﺴﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻟﻴﻞ ﻋﺪﻡ ﺁﮔﺎﻫﻲ ﻭ ﺩﺍﻧﺶ ﻧﺴﺒﺖ‬ ‫ﺑﻪ ﻫﻮﻳﺖ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺩﺳﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺼﻮﺭﺕ‬

‫‪ broadcast‬ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺜﻼ" ﻫﺮ ﺯﻣﺎﻥ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺟﺪﻳﺪ ﻭﻳﺎ ﻳﮑﺪﺳﺘﮕﺎﻩ ﺑﻪ ﺷﺒﮑﻪ ﻭﺍﺭﺩ‬

‫ﻣﻲ ﺷﻮﺩ ‪ ،‬ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺑﺮﺍﻱ ﻣﻌﺮﻓﻲ ﻭ ﺣﻀﻮﺭ ﺧﻮﺩ ﺩﺭ ﺷﺒﮑﻪ‬ ‫ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﺳﺎﻳﺮ ﮔﺮﻩ ﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﺍﻓﺰﻭﺩﻥ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ ﻟﻴﺴﺖ ﺧﻮﺩ ﻭ ﺑﺮﻗﺮﺍﺭﻱ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺁﻥ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ‬

‫ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﻧﻴﺎﺯ ﺑﻪ ﻣﻌﺮﻓﻲ ﺧﻮﺩ ﺑﻪ ﺳﺎﻳﺮ ﺑﺨﺶ ﻫﺎﻱ ﺷﺒﮑﻪ ﺭﺍ ﺩﺍﺷﺘﻪ ﻭ ﻳﺎ ﻧﺴﺒﺖ ﺑﻪ ﻫﻮﻳﺖ‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺍﻃﻼﻋﺎﺕ ﺷﻨﺎﺧﺖ ﻻﺯﻡ ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻧﻮﻉ ‪ Broadcast‬ﺑﺮﺍﻱ ﺳﺎﻳﺮ‬ ‫ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﻮﺯﻩ ‪ Broadcast‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺭﻭﺗﺮ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﻤﻲ ﺩﻫﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺁﺩﺭﺱ ﻳﮑﺪﺳﺘﮕﺎﻩ ﻣﺸﺨﺺ‬

‫ﻧﮕﺮﺩﺩ ‪ ،‬ﺭﻭﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﻣﺴﻴﺮﻳﺎﺑﻲ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻮﺭﺩ ﻧﻈﺮ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﻭﻳﮋﮔﻲ ﻓﻮﻕ ﺩﺭ‬

‫ﻣﻮﺍﺭﺩﻳﮑﻪ ﻗﺼﺪ ﺟﺪﺍﺳﺎﺯﻱ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﻣﺪ ﻧﻈﺮ ﺑﺎﺷﺪ ‪ ،‬ﺑﺴﻴﺎﺭ ﺍﻳﺪﻩ ﺁﻝ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﻭﻟﻲ ﺯﻣﺎﻧﻴﮑﻪ ﻫﺪﻑ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻴﻦ ﺑﺨﺶ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻳﮏ ﺷﺒﮑﻪ ﺑﺎﺷﺪ‪ ،‬ﻣﻄﻠﻮﺏ ﺑﻨﻈﺮ‬

‫ﻧﻤﻲ ﺁﻳﺪ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﺎ ﻫﺪﻑ ﺑﺮﺧﻮﺭﺩ‬ ‫ﺑﺎ ﻣﺸﮑﻞ ﻓﻮﻕ ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬

‫ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ LAN‬ﺑﺮ ﺍﺳﺎﺱ ﺗﮑﻨﻮﻟﻮﮊﻱ ‪ packet-switching‬ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺳﻮﺋﻴﭻ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﻭ ﺳﮕﻤﻨﺖ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻭﻟﻴﻪ ﺩﺭ ﻳﮏ‬

‫ﻣﺤﻞ ﻣﻮﻗﺖ ) ﺑﺎﻓﺮ( ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ )‪ (MAC‬ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺪﺭ ﺧﻮﺍﻧﺪﻩ‬ ‫ﺷﺪﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﻟﻴﺴﺘﻲ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺟﺪﻭﻝ ‪ ) Lookup‬ﺟﺴﺘﺠﻮ( ﻣﻘﺎﻳﺴﻪ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ LAN‬ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﺗﺮﻧﺖ‪ ،‬ﻫﺮ ﻓﺮﻳﻢ ﺍﺗﺮﻧﺖ ﺷﺎﻣﻞ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺧﺎﺹ ﺍﺳﺖ ‪ .‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻓﻮﻕ ﺷﺎﻣﻞ ﻳﮏ ﻋﻨﻮﺍﻥ )ﻫﺪﺭ( ﺧﺎﺹ ﻭ ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺕ‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﺁﺩﺭﺱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺖ‪.‬‬ ‫ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻣﺒﺘﻨﻲ ﺑﺮ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺴﻴﺮﻳﺎﺑﻲ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺯ‬

‫ﺳﻪ ﺭﻭﺵ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫• ‪Cut-Through‬‬ ‫• ‪Store-and-forward‬‬ ‫• ‪Fragment-free‬‬ ‫ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ ، Cut-through‬ﺑﻼﻓﺎﺻﻠﻪ ﭘﺲ ﺍﺯ ﺗﺸﺨﻴﺺ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ‬ ‫‪ ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺧﻮﺍﻧﺪﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﺷﺶ ﺑﺎﻳﺖ ﺍﻃﻼﻋﺎﺕ ﮐﻪ ﺷﺎﻣﻞ‬ ‫ﺁﺩﺭﺱ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﻼﻓﺎﺻﻠﻪ ﻋﻤـﻠﻴﺎﺕ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﮔﺮﻩ ﻣﻘـــﺼﺪ ﺁﻏـــﺎﺯ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪) .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺩﺭﻳﺎﻓﺖ ﺳﺎﻳﺮ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ (‪ .‬ﺑﺎ ﺗﻮﺟﻪ‬

‫ﺑﻪ ﻋﺪﻡ ﻭﺟﻮﺩ ﮐﻨﺘﺮﻝ ﻫﺎﻱ ﻻﺯﻡ ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ‪ ،‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ‬ ‫ﺯﻳﺎﺩﻱ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ ، store-and-forward‬ﺗﻤﺎﻡ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺑﺎﻓﺮ ﻣﺮﺑﻮﻃﻪ ﺫﺧﻴﺮﻩ ﻭ‬

‫ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺑﺮﺭﺳﻲ ﺧﻄﺎﺀ )‪ (CRC‬ﻭ ﺳﺎﻳﺮ ﻣﺴﺎﺋﻞ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺍﺭﺍﻱ ﺧﻄﺎﺀ ﺑﺎﺷﺪ‪ ،‬ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺩﻭﺭ ﺍﻧﺪﺍﺧﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪. .‬ﺩﺭ ﻏﻴﺮﺍﻳﻨﺼﻮﺭﺕ‪ ،‬ﺳﻮﺋﻴﭻ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﺩﺭﺱ‪، MAC‬‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﮔﺮﻩ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻏﻠﺐ ﺳﻮﺋﻴﭻ ﻫﺎ ﺍﺯ ﺗﺮﮐﻴﺐ ﺩﻭ ﺭﻭﺵ‬

‫ﮔﻔﺘﻪ ﺷﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺳﻮﺋﻴﭻ ﻫﺎ ﺍﺯ ﺭﻭﺵ ‪ cut-through‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺷﺪﻩ ﻭ ﺑﻤﺤﺾ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﺍﺯ ﺭﻭﺵ ‪ store-and-forward‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳـﻨﺪ‪.‬‬

‫ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﻣﺴﻴﺮﻳﺎﺑﻲ ﺗﺮﺍﻓﻴﮏ ﺩﺭ ﺳﻮﺋﻴﭻ ﻫﺎ ﮐﻪ ﮐﻤﺘﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪،‬‬ ‫‪ fragment-free‬ﺍﺳﺖ‪ .‬ﺭﻭﺵ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ‪ cut-through‬ﺑﻮﺩﻩ ﺑﺎ ﺍﻳﻦ ﺗﻔﺎﻭﺕ ﮐﻪ‬ ‫ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ‪ ٦٤‬ﺑﺎﻳﺖ ﺁﻥ ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ LAN‬ﺩﺍﺭﺍﻱ ﻣﺪﻝ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺯ ﻧﻘﻄﻪ ﻧﻈﺮ ﻃﺮﺍﺣﻲ ﻓﻴﺰﻳﮑﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺳﻪ‬ ‫ﻣﺪﻝ ﺭﺍﻳﺞ ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺑﺸﺮﺡ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫‪ . Shared memory‬ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺗﻤﺎﻡ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻭﻟﻴﻪ‬ ‫ﺩﺭ ﺑﺎﻓﺮ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺭﺍ ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺎﻓﺮ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﻣﺸﺘﺮﮎ ﺗﻮﺳﻂ‬

‫ﺗﻤﺎﻡ ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﻮﺋﻴﭻ ) ﺍﺗﺼﺎﻻﺕ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﮑﻤﮏ ﭘﻮﺭﺕ ﻣﺮﺑﻮﻃﻪ ﺑﺮﺍﻱ ﮔﺮﻩ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ‬ ‫ﺷﺪ‪.‬‬

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‫‪ .Matrix‬ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﺒﮑﻪ) ﺗﻮﺭ( ﺩﺍﺧﻠﻲ ﻣﺎﺗﺮﻳﺲ ﻣﺎﻧﻨﺪ ﺑﻮﺩﻩ‬ ‫ﮐﻪ ﭘﻮﺭﺕ ﻫﺎﻱ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ ﻫﻤﺪﻳﮕﺮ ﺭﺍ ﻗﻄﻊ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮ ﺭﻭﻱ ﭘﻮﺭﺕ ﻭﺭﻭﺩﻱ ﺗﺸﺨﻴﺺ ﺩﺍﺩﻩ ﺷﺪ‪ ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺁﻥ ﺑﺎ ﺟﺪﻭﻝ‬ ‫‪ lookup‬ﻣﻘﺎﻳﺴﻪ ﺗﺎ ﭘﻮﺭﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﺮﻭﺟﻲ ﺁﻥ ﻣﺸﺨﺺ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺳﻮﺋﻴﭻ‬

‫ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﻭ ﺩﺭ ﻣﺤﻠﻲ ﮐﻪ ﭘﻮﺭﺕ ﻫﺎ ﻫﻤﺪﻳﮕﺮ ﺭﺍ ﻗﻄﻊ ﻣﻲ ﮐﻨﻨﺪ‪،‬‬ ‫ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫‪ . Architecture Bus‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﺠﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ‬ ‫) ﺗﻮﺭ( ‪ ،‬ﺍﺯ ﻳﮏ ﻣﺴﻴﺮ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺧﻠﻲ )‪ (Bus‬ﺍﺳﺘﻔﺎﺩﻩ ﻭ ﻣﺴﻴﺮ ﻓﻮﻕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫‪ TDMA‬ﺗﻮﺳﻂ ﺗﻤﺎﻡ ﭘﻮﺭﺕ ﻫﺎ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﺣﺎﻓﻈﻪ ﺍﺧﺘﺼﺎﺻﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪Transparent Bridging‬‬ ‫ﺍﮐﺜﺮ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ LAN‬ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﺗﺮﻧﺖ ﺍﺯ ﺳﻴﺴﺘﻢ ﻱ ﺑﺎ ﻧﺎﻡ ‪transparent bridging‬‬ ‫ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﺟﺪﺍﻭﻝ ﺁﺩﺭﺱ ‪ lookup‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺍﻣﮑﺎﻥ ﻳﺎﺩﮔﻴﺮﻱ‬

‫ﻫﺮ ﭼﻴﺰﻱ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺤﻞ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ‪ ،‬ﺑﺪﻭﻥ ﺣﻤﺎﻳﺖ ﻣﺪﻳﺮﻳﺖ ﺷﺒﮑﻪ ﺭﺍ‬

‫ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺩﺍﺭﻱ ﭘﻨﺞ ﺑﺨﺶ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪:‬‬ ‫•‬ ‫•‬ ‫•‬ ‫•‬ ‫•‬

‫‪Learning‬‬ ‫‪Flooding‬‬ ‫‪Filtering‬‬ ‫‪Forwarding‬‬ ‫‪Aging‬‬

‫ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻓﻮﻕ ﺑﺸﺮﺡ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﺳﻮﺋﻴﭻ ﺑﻪ ﺷﺒﮑﻪ ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﻭ ﺗﻤﺎﻡ ﺳﮕﻤﻨﺖ ﻫﺎ ﺑﻪ ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﻮﺋﻴﭻ ﻣﺘﺼﻞ‬

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‫ﮔﺮﻩ ‪ A‬ﺑﺮ ﺭﻭﻱ ﺍﻭﻟﻴﻦ ﺳﮕﻤﻨﺖ ) ﺳﮕﻤﻨﺖ ‪ ،( A‬ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻳــﮕﺮ‬

‫ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪.‬‬

‫) ﮔﺮﻩ ‪ ( B‬ﺩﺭ ﺳﮕﻤﻨﺖ ﺩﻳﮕﺮ ) ﺳﮕﻤﻨﺖ ‪ ( C‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪.‬‬

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‫ﺳﻮﺋﻴﭻ ﺍﻭﻟﻴﻦ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺍﺯ ﮔﺮﻩ ‪ A‬ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺁﺩﺭﺱ ‪ MAC‬ﺁﻥ‬

‫ﺧﻮﺍﻧﺪﻩ ﺷﺪﻩ ﻭ ﺁﻥ ﺭﺍ ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﺳﮕﻤﻨﺖ ‪ A‬ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ‬

‫ﺗﺮﺗﻴﺐ ﺳﻮﺋﻴﭻ ﺍﺯ ﻧﺤﻮﻩ ﻳﺎﻓﺘﻦ ﮔﺮﻩ ‪ A‬ﺁﮔﺎﻫﻲ ﭘﻴﺪﺍ ﮐﺮﺩﻩ ﻭ ﺍﮔﺮ ﺩﺭ ﺁﻳﻨﺪﻩ ﮔﺮﻩ ﺍﻱ‬ ‫ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﮔﺮﻩ ‪ A‬ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﺳﻮﺋﻴﭻ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺁﺩﺭﺱ ﺁﻥ‬

‫ﻣﺸﮑﻠﻲ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺭﺍ ‪ Learning‬ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬ ‫•‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺳﻮﺋﻴﭻ ﺩﺍﻧﺸﻲ ﻧﺴﺒﺖ ﺑﻪ ﻣﺤﻞ ﮔﺮﻩ ‪ B‬ﻧﺪﺍﺭﺩ‪ ،‬ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ‬ ‫ﺑﺮﺍﻱ ﺗﻤﺎﻡ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ )ﺑﺠﺰ ﺳﮕﻤﻨﺖ ‪ A‬ﮐﻪ ﺍﺧﻴﺮﺍ" ﻳﮑﻲ ﺍﺯ ﮔﺮﻩ‬ ‫ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺁﻥ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ (.‬ﻓﺮﺁﻳﻨﺪ ﺍﺭﺳﺎﻝ ﻳﮏ‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭻ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﻳﮏ ﮔﺮﻩ ﺧﺎﺹ ﺑﺮﺍﻱ ﺗﻤﺎﻡ ﺳﮕﻤﻨﺖ‬ ‫ﻫﺎ ‪ Flooding ،‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫•‬

‫ﮔﺮﻩ ‪ B‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﻪ ﻋﻨﻮﺍﻥ‬ ‫‪ Acknowledgement‬ﺑﺮﺍﻱ ﮔﺮﻩ ‪ A‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

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‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﮔﺮﻩ ‪ B‬ﺑﻪ ﺳﻮﺋﻴﭻ ﻣﻲ ﺭﺳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺯﻣﺎﻥ‪ ،‬ﺳﻮﺋﻴﭻ ﻗﺎﺩﺭ‬ ‫ﺑﻪ ﺫﺧﻴﺮﻩ ﮐﺮﺩﻥ ﺁﺩﺭﺱ ‪ MAC‬ﮔﺮﻩ ‪ B‬ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﺳﮕﻤﻨﺖ ‪ C‬ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺳﻮﺋﻴﭻ ﺍﺯ ﺁﺩﺭﺱ ﮔﺮﻩ ‪ A‬ﺁﮔﺎﻫﻲ ﺩﺍﺭﺩ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ"‬

‫ﺑﺮﺍﻱ ﺁﻥ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﮔﺮﻩ ‪ A‬ﺩﺭ ﺳﮕﻤﻨﺘﻲ ﻣﺘﻔﺎﻭﺕ ﻧﺴﺒﺖ ﺑﻪ ﮔﺮﻩ ‪ B‬ﻗﺮﺍﺭ‬ ‫ﺩﺍﺭﺩ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺳﻮﺋﻴﺞ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﻭ ﺳﮕﻤﻨﺖ ﺭﺍ ﺑﻪ‬ ‫ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﺎﺋﻴﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ‪ Forwarding‬ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻌﺪﻱ ﺍﺯ ﮔﺮﻩ ‪ A‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﺮﺍﻱ ﮔﺮﻩ ‪ B‬ﺑﻪ ﺳﻮﺋﻴﭻ‬ ‫ﻣﻲ ﺭﺳﺪ‪ ،‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺳﻮﺋﻴﺞ ﺍﺯ ﺁﺩﺭﺱ ﮔﺮﻩ ‪ B‬ﺁﮔﺎﻫﻲ ﺩﺍﺭﺩ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﻓﻮﻕ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﺮﺍﻱ ﮔﺮﻩ ‪ B‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﮔﺮﻩ ‪ C‬ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺳﻮﺋﻴﭻ ﺑﺮﺍﻱ ﮔﺮﻩ ‪ A‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﺳﻮﺋﻴﭻ ﺁﺩﺭﺱ‬

‫‪ MAC‬ﮔﺮﻩ ‪ C‬ﺭﺍ ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﺳﮕﻤﻨﺖ ‪ A‬ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺳﻮﺋﻴﭻ‬ ‫ﺁﺩﺭﺱ ﮔﺮﻩ ‪ A‬ﺭﺍ ﺩﺍﻧﺴﺘﻪ ﻭ ﻣﺸﺨﺺ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﺩﻭ ﮔﺮﻩ ‪ A‬ﻭ ‪ C‬ﺩﺭ ﻳﮏ ﺳﮕﻤﻨﺖ‬ ‫‪284‬‬

‫ﻗﺮﺍﺭ ﺩﺍﺭﻧﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺳﮕﻤﻨﺖ ‪ A‬ﺑﺎ ﺳﮕﻤﻨﺖ ﺩﻳﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ﮔﺮﻩ ‪ C‬ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺳﻮﺋﻴﭻ ﺍﺯ ﺣﺮﮐﺖ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﺑﻴﻦ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﻤﺎﻧﻌﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺭﺍ‬ ‫‪ Filtering‬ﻣﻲ ﮔﻮﻳﻨﺪ‪.‬‬

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‫‪ Learning‬ﻭ ‪ Flooding‬ﺍﺩﺍﻣﻪ ﻳﺎﻓﺘﻪ ﻭ ﺑﻤﻮﺍﺯﺍﺕ ﺁﻥ ﺳﻮﺋﻴﭻ‪ ،‬ﺁﺩﺭﺱ ﻫﺎﻱ ‪MAC‬‬ ‫ﻣﺮﺑﻮﻁ ﺑﻪ ﮔﺮﻩ ﻫﺎ ﺭﺍ ﺩﺭ ﺟﺪﺍﻭﻝ ‪ Lookup‬ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﮐﺜﺮ ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺍﺭﺍﻱ‬ ‫ﺣﺎﻓﻈﻪ ﮐﺎﻓﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ ﺟﺪﺍﻭﻝ ‪ Lookup‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﻬﻴﻨﻪ‬

‫ﺳﺎﺯﻱ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻗﺪﻳﻤﻲ ﺗﺮ ﺍﺯ ﺟﺪﺍﻭﻝ ﻓﻮﻕ ﺣﺬﻑ ﺗﺎ ﻓﺮﺁﻳﻨﺪ ﺟﺴﺘﺠﻮ‬ ‫ﻭ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ﻫﺎ ﺩﺭ ﻳﮏ ﺯﻣﺎﻥ ﻣﻌﻘﻮﻝ ﻭ ﺳﺮﻳﻌﺘﺮ ﺍﻧﺠﺎﻡ ﭘﺬﻳﺮﺩ‪ .‬ﺑﺬﻳﻦ ﻣﻨﻈﻮﺭ ﺳﻮﺋﻴﺞ‬ ‫ﻫﺎ ﺍﺯ ﺭﻭﺷﻲ ﺑﺎ ﻧﺎﻡ ‪ aging‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ ‪ Entry‬ﺑﺮﺍﻱ ﻳﮏ ﮔﺮﻩ‬

‫ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﺍﺿﺎﻓﻪ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺑﻪ ﺁﻥ ﻳﮏ ﺯﻣﺎﻥ ﺧﺎﺹ ﻧﺴﺒﺖ ﺩﺍﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﻫﺮ ﺯﻣﺎﻥ ﮐﻪ ﺑﺴﺘﻪ ﺍﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﮔﺮﻩ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺯﻣﺎﻥ‬ ‫ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻬﻨﮕﺎﻡ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﻮﺋﻴﭻ ﺩﺍﺭﺍﻱ ﻳﮏ ﻳﮏ ﺗﺎﻳﻤﺮ ﻗﺎﺑﻞ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺑﻮﺩﻩ ﮐﻪ ﺑﺎ‬ ‫ﻋﺚ ﻣﻲ ﺷﻮﺩ‪ Entry ،‬ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﮐﻪ ﻣﺪﺕ ﺯﻣﺎﻥ ﺧﺎﺻﻲ‬

‫ﺍﺯ ﺁﻧﻬﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻧﺸﺪﻩ ﻭ ﻳﺎ ﺑﻪ ﺁﻧﻬﺎ ﻣﺮﺍﺟﻌﻪ ﺍﻱ ﻧﺸﺪﻩ ﺍﺳﺖ‪ ،‬ﺣﺬﻑ ﮔﺮﺩﻧﺪ ‪ .‬ﺑﺎ ﺣﺬﻑ‬ ‫‪ Entry‬ﻫﺎﻱ ﻏﻴﺮﺿﺮﻭﺭﻱ‪ ،‬ﺣﺎﻓﻈﻪ ﻗﺎﺑﻞ ﺍﺳﺘـــﻔﺎﺩﻩ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ‪ Entry‬ﻫﺎ ﺑﻴﺸـــﺘﺮ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺩﺭ ﻣﺜﺎﻝ ﻓﻮﻕ‪ ،‬ﺩﻭ ﮔﺮﻩ ﺳﮕﻤﻨﺖ ‪ A‬ﺭﺍ ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﻭ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ‪ A‬ﻭ ‪ D‬ﺑﺼﻮﺭﺕ‬ ‫ﻣﺴﺘﻘﻞ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﻳﺪﻩ ﺁﻝ ﻣﺒﺘﻨﻲ ﺑﺮ ﺳﻮﺋﻴﭻ‪ ،‬ﻫﺮﮔﺮﻩ ﺩﺍﺭﺍﻱ ﺳﮕﻤﻨﺖ‬ ‫ﺍﺧﺘﺼﺎﺻﻲ ﻣﺮﺑﻮﻁ ﺑﺨﻮﺩ ﺍﺳﺖ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺍﻣﮑﺎﻥ ﺗﺼﺎﺩﻡ ﺣﺬﻑ ﻭ ﻧﻴﺎﺯﻱ ﺑﻪ ﻋﻤﻠﻴﺎﺕ‬ ‫‪ Filtering‬ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

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‫ﻓﺮﺍﻭﺍﻧﻲ ﻭ ﺁﺷﻔﺘﮕﻲ ﺍﻧﺘﺸﺎﺭ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺎ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺳﺘﺎﺭﻩ )‪ (Star‬ﻭ ﻳﺎ ﺗﺮﮐﻴﺐ ‪ Bus‬ﻭ ﻭ‪ Star‬ﻳﮑﻲ ﺍﺯ ﻋﻨﺎﺻﺮ‬

‫ﺍﺻﻠﻲ ﺷﺒﮑﻪ ﮐﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺍﺯ ﮐﺎﺭ ﺍﻓﺘﺎﺩﻥ ﺷﺒﮑﻪ ﮔﺮﺩﺩ‪ ،‬ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺍﺳﺖ‪ .‬ﻓﺮﺽ‬ ‫ﮐﻨﻴﺪ ﺷﺒﮑﻪ ﺍﻱ ﺑﺎ ﺳﺎﺧﺘﺎﺭ ﺯﻳﺮ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪:‬‬

‫ﺩﺭ ﻣﺜﺎﻝ ﻓﻮﻕ‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﻮﺋﻴﭻ ‪ A‬ﻭ ﻳﺎ ‪ C‬ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﮔﺮﺩﻧﺪ‪ ،‬ﺗﻤﺎﻡ ﮔﺮﻩ ﻫﺎﻱ‬ ‫ﻣﺘﺼﻞ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻓﻮﻕ ﻧﻴﺰ ﺗﺤﺖ ﺗﺎﺛﻴﺮ ﺍﺷﮑﺎﻝ ﻓﻮﻕ ﻗﺮﺍﺭ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪.‬‬ ‫ﮔﺮﻩ ﻫﺎﻱ ﻣﺘﺼﻞ ﺑﻪ ﺳﻮﺋﻴﭻ ﺩﻳﮕﺮ )‪ (B‬ﮐﻤﺎﮐﻦ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺧﻮﺩ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ‬

‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﻮﺋﻴﭻ ‪ C‬ﺑﺎ ﺍﺷﮑﺎﻝ ﻣﻮﺍﺟﻪ ﮔﺮﺩﺩ‪ ،‬ﺗﻤﺎﻡ ﺷﺒﮑﻪ ﺍﺯ ﮐﺎﺭ ﺧﻮﺍﻫﺪ ﺍﻓﺘﺎﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ‬ ‫ﺍﺿﺎﻓﻪ ﮐﺮﺩﻥ ﺳﮕﻤﻨﺖ ﺩﻳﮕﺮ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺳﻮﺋﻴﭻ ‪ A‬ﻭ ‪ C‬ﭼﻪ ﺍﺗﻔﺎﻗﻲ ﺧﻮﺍﻫﺪ ﺍﻓﺘﺎﺩ‪.‬‬

‫ﺩﺭ ﺣﺎﻟﺖ ﻓﻮﻕ ‪ ،‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮑﻲ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﺎ ﺍﺷﮑﺎﻝ ﻣﻮﺍﺟﻪ ﮔﺮﺩﺩ ‪ ،‬ﺷﺒﮑﻪ ﮐﻤﺎﮐﻦ‬

‫ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺍﺋﻪ ﺧﺪﻣﺎﺕ ﺧﻮﺩﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺎ ﺍﻓﺰﺩﻭﻥ ﺳﮕﻤﻨﺖ ﻓﻮﻕ‪ ،‬ﺷﺒﮑﻪ ﺍﺯ ﺣﺎﻟﺖ ﻭﺍﺑﺴﺘﮕﻲ‬ ‫ﺑﻪ ﻳﮏ ﻧﻘﻄﻪ ﺧﺎﺭﺝ ﻭ ﻳﮏ ﻧﻮﻉ " ﻓﺮﺍﻭﺍﻧﻲ" ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﺑﺎ ﺣﻞ ﻣﺸﮑﻞ ﻭﺍﺑﺴﺘﮕﻲ ﻋﻤﻠﻴﺎﺗﻲ ﺷﺒﮑﻪ ﺑﻪ ﻳﮏ ﻧﻘﻄﻪ‪ ،‬ﻣﺸﮑﻞ ﺩﻳﮕﺮﻱ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻳﺪ‪.‬‬ ‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻗﺒﻼ" ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﺼﻮﺭﺕ ﻫﻮﺷﻤﻨﺪﺍﻧﻪ ﺍﺯﺁﺩﺭﺱ ﻭ ﻣﺤﻞ ﻫﺮ ﻳﮏ‬ ‫ﺍﺯ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺁﮔﺎﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺷﺮﺍﻳﻂ ﺍﻳﺠﺎﺩ ﺷﺪﻩ‪ ،‬ﺗﻤﺎﻡ ﺳﻮﺋﻴﺞ‬ ‫ﻫﺎ ﺩﺭ ﻳﮏ ‪ Loop‬ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬

‫ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ ﻳﮏ ﮔﺮﻩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺗﻮﺳﻂ ﺳﻮﺋﻴﭽﻲ ﺍﺯ ﺳﮕﻤﻨﺖ ﺩﻳﮕﺮ ﺁﻣﺪﻩ ﺑﺎﺷﺪ‪.‬‬ ‫‪286‬‬

‫ﻣﺜﻼ" ﻓﺮﺽ ﻧﻤﺎﺋﻴﺪ ﮐﻪ ﮔﺮﻩ ‪ B‬ﺑﻪ ﺳﻮﺋﻴﭻ ‪ A‬ﻣﺘﺼﻞ ﻭ ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ ﮔﺮﻩ ‪B‬‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﮕﻤﻨﺖ ‪ B‬ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ .‬ﺳﻮﺋﻴﭻ ‪ A‬ﺷﻨﺎﺧﺘﻲ ﻧﺴﺒﺖ ﺑﻪ ﮔﺮﻩ ‪ A‬ﻧﺪﺍﺭﺩ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ‬ ‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﮔﺮﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺯ ﻃﺮﻳﻖ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ‪ A‬ﻭ ﻳﺎ ‪ C‬ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ )‪ B‬ﻭ ﻳﺎ‬ ‫‪ (C‬ﺣﺮﮐﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺳﻮﺋﻴﭻ ‪ ،B‬ﮔﺮﻩ ‪ B‬ﺭﺍ ﺑﻪ ﺟﺪﻭﻝ ‪ Lookup‬ﺧﻮﺩ ﺍﺿـــــﺎﻓﻪ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ ) .‬ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ ‪ .(A‬ﺳﻮﺋﻴﭻ ‪ C‬ﺁﺩﺭﺱ ﮔﺮﻩ ‪ B‬ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺳﮕﻤﻨﺖ‬ ‫‪ C‬ﺩﺭ ﺟﺪﻭﻝ ‪ Lookup‬ﺧﻮﺩ ﺫﺧﻴﺮﻩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﻫﻴﭽﮑﺪﺍﻡ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ‬ ‫ﺗﺎﮐﻨﻮﻥ ﺷﻨﺎﺧﺘﻲ ﻧﺴﺒﺖ ﺑﻪ ﺁﺩﺭﺱ ﮔﺮﻩ ‪ A‬ﺑﺪﺳﺖ ﻧﻴﺎﻭﺭﺩﻩ ﺍﻧﺪ ‪ ،‬ﺳﮕﻤﻨﺖ ‪ B‬ﺑﺮﺍﻱ ﭘﻴﺪﺍ ﮐﺮﺩﻥ‬

‫ﮔﺮﻩ ‪ A‬ﻣﻮﺭﺩ ﺑﺮﺭﺳﻲ ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﮔﺮﻓﺖ ‪ .‬ﻫﺮ ﺳﻮﺋﻴﺞ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺭﺍ‬ ‫ﺩﺭﻳﺎﻓﺖ ﻭ ﻣﺠﺪﺩﺍ" ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺳﮕﻤﻨﺖ ﻫﺎ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ) .‬ﭼﻮﻥ ﻫﻴﭽﮑﺪﺍﻡ ﻫﻨﻮﺯ‬ ‫ﺩﺍﻧﺸﻲ ﻧﺴﺒﺖ ﺑﻪ ﻣﺤﻞ ﮔﺮﻩ ‪ A‬ﺭﺍ ﮐﺴﺐ ﻧﮑﺮﺩﻩ ﺍﻧﺪ( ﺳﻮﺋﻴﺞ ‪ A‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ‬

‫ﻫﺮ ﻳﮏ ﺍﺯ ﺳﻮﺋﻴﭻ ﻫﺎ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﻣﺠﺪﺩﺍ" ﺁﻥ ﺭﺍ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺳﮕﻤﻨﺖ ﻫﺎ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺩﺭ ﺟﻨﻴﻦ ﺷﺮﺍﻳﻄﻲ ﻳﮏ ﻧﻮﻉ " ﺁﺷﻔﺘﮕﻲ ﺍﻧﺘﺸﺎﺭ " ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﺷﺮﺍﻳﻂ ﻓﻮﻕ ﺑﺎﻋﺚ ﺍﻳﺠﺎﺩ‬

‫ﻣﺸﮑﻞ ﺗﺮﺍﻓﻴﮑﻲ ﺩﺭ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﺑﺎ ﻧﺎﻡ‬ ‫‪ Spanning trees‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫‪Spanning tress‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭﻱ ﭘﻴﺸﮕﻴﺮﻱ ﺍﺯ ﻣﺴﺌﻠﻪ " ﺁﺷﻔﺘﮕﻲ ﺍﻧﺘﺸﺎﺭ" ﻭ ﺳﺎﻳﺮ ﺍﺛﺮﺍﺕ ﺟﺎﻧﺒﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ‬ ‫‪ Looping‬ﺷﺮﮐﺖ ‪ DEC‬ﭘﺮﻭﺗﮑﻠﻲ ﺑﺎ ﻧﺎﻡ ‪ (Spanning-tree Protocol(STP‬ﺭﺍ‬ ‫ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩﻩ ﺍﺳﺖ ‪ .‬ﭘﺮﻭﺗﮑﻞ ﻓﻮﻕ ﺑﺎ ﻣﺸﺨﺼﻪ ‪ d٨٠٢,١‬ﺗﻮﺳﻂ ﻣﻮﺳﺴﻪ ‪ IEEE‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‬ ‫‪287‬‬

‫ﺷﺪﻩ ﺍﺳﺖ‪ tree Spanning .‬ﺍﺯ ﺍﻟﮕﻮﺭﻳﺘﻢ ‪(STA(Spanning-tree algoritm‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻟﮕﻮﺭﻳﺘﻢ ﻓﻮﻕ ﺑﺮﺭﺳﻲ ﺧﻮﺍﻫﺪ ﮐﺮﺩ ﺁﻳﺎ ﻳﮏ ﺳﻮﺋﻴﭻ ﺩﺍﺭﺍﻱ ﺑﻴﺶ ﺍﺯ ﻳﮏ‬ ‫ﻣﺴﻴﺮ ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻳﮏ ﮔﺮﻩ ﺧﺎﺹ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﻭﺟﻮﺩ ﻣﺴﻴﺮﻫﺎﻱ ﻣﺘﻌﺪﺩ‪ ،‬ﺑﻬﺘﺮﻳﻦ‬ ‫ﻣﺴﻴﺮ ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﻳﺮ ﻣﺴﻴﺮﻫﺎ ﮐﺪﺍﻡ ﺍﺳﺖ؟ ﻧﺤﻮﻩ ﻋﻤﻠﻴﺎﺕ ‪ STP‬ﺑﺸﺮﺡ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﺑﻪ ﻫﺮ ﺳﻮﺋﻴﺞ ‪ ،‬ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﻣﺸﺨﺼﻪ ﻫﺎ )‪ (ID‬ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻳﮑﻲ ﺍﺯ‬ ‫ﻣﺸﺨﺼﻪ ﻫﺎ ﺑﺮﺍﻱ ﺳﻮﺋﻴﭻ ﻭ ﺳﺎﻳﺮ ﻣﺸﺨﺼﻪ ﻫﺎ ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺸﺨﺼﻪ ﺳﻮﺋﻴﭻ‪ (Bridge ID(BID ،‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﺩﺍﺭﺍﻱ ﻫﺸﺖ‬

‫ﺑﺎﻳﺖ ﺍﺳﺖ‪ .‬ﺩﻭ ﺑﺎﻳﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺍﻭﻟﻮﻳﺖ ﻭ ﺷﺶ ﺑﺎﻳﺖ ﺑﺮﺍﻱ‬

‫ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﺁﺩﺭﺱ ‪ MAC‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺸﺨﺼﻪ ﭘﻮﺭﺕ ﻫﺎ‪ ،‬ﺷﺎﻧﺰﺩﻩ ﺑﻴﺘﻲ‬ ‫ﺍﺳﺖ ‪ .‬ﺷﺶ ﺑﻴﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﻨﻈﻴﻤﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻭﻟﻮﻳﺖ ﻭ ﺩﻩ ﺑﻴﺖ ﺩﻳﮕﺮ ﺑﺮﺍﻱ‬ ‫ﺍﺧﺘﺼﺎﺹ ﻳﮏ ﺷﻤﺎﺭﻩ ﺑﺮﺍ ﻱ ﭘﻮﺭﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺳﺖ‪.‬‬ ‫•‬

‫ﺑﺮﺍﻱ ﻫﺮ ﻣﺴﻴﺮ ﻳﮏ ‪ Path Cost‬ﻣﺤﺎﺳﺒﻪ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻧﺤﻮﻩ ﻣﺤﺎﺳﺒﻪ ﭘﺎﺭﺍﻣﺘﺮ ﻓﻮﻕ ﺑﺮ‬ ‫ﺍﺳﺎﺱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﻣﻮﺳﺴﻪ ‪ IEEE‬ﺍﺳﺖ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺤﺎﺳﺒﻪ‬ ‫ﻣﻘﺎﺩﺭ ﻓﻮﻕ‪ ١,٠٠٠ ،‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ) ﻳﮏ ﮔﻴﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ( ﺭﺍ ﺑﺮ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‬ ‫ﺳﮕﻤﻨﺖ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﭘﻮﺭﺕ ‪ ،‬ﺗﻘﺴﻴﻢ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻳﮏ ﺍﺗﺼﺎﻝ ‪ ١٠‬ﻣﮕﺎﺑﻴﺖ‬ ‫ﺩﺭ ﺛﺎﻧﻴﻪ ‪ ،‬ﺩﺍﺭﺍﻱ ‪ Cost‬ﺑﻪ ﻣﻴﺰﺍﻥ ‪ ١٠٠‬ﺍﺳﺖ )‪ ١,٠٠٠‬ﺗﻔﺴﻴﻢ ﺑﺮ ‪ .( ١٠‬ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﻫﻤﺎﻫﻨﮓ ﺷﺪﻥ ﺑﺎ ﺍﻓﺰﺍﻳﺶ ﺳﺮﻋﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ Cost‬ﻧﻴﺰ‬

‫ﺍﺻﻼﺡ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺟﺪﻭﻝ ﺯﻳﺮ ﻣﻘﺎﺩﻳﺮ ﺟﺪﻳﺪ ‪ STP Cost‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬ ‫) ﻣﻘﺪﺍﺭ ‪ cost Path‬ﻣﻲ ﺗﻮﺍﻧﺪ ﻳﮏ ﻣﻘﺪﺍﺭ ﺩﻟﺨﻮﺍﻩ ﺑﻮﺩﻩ ﮐﻪ ﺗﻮﺳﻂ ﻣﺪﻳﺮﻳﺖ ﺷﺒﮑﻪ‬ ‫ﺗﻌﺮﻳﻒ ﻭ ﻣﺸﺨﺺ ﻣﻲ ﮔﺮﺩﺩ (‬ ‫‪STP Cost Value Bandwidth‬‬ ‫‪4 Mbps‬‬

‫‪250‬‬

‫‪10 Mbps‬‬

‫‪100‬‬

‫‪16 Mbps‬‬

‫‪62‬‬

‫‪288‬‬

‫‪45 Mbps‬‬

‫‪39‬‬

‫‪100 Mbps‬‬

‫‪19‬‬

‫‪155 Mbps‬‬

‫‪14‬‬

‫‪622 Mbps‬‬

‫‪6‬‬

‫‪1 Gbps‬‬

‫‪4‬‬

‫‪2‬‬ ‫‪10 Gbps‬‬ ‫• ﻫﺮ ﺳﻮﺋﻴﭻ ﻓﺮﺁﻳﻨﺪﻱ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﺨﺎﺏ ﻣﺴﻴﺮﻫﺎﻱ ﺷﺒﮑﻪ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺗﻮﺳﻂ ﻫﺮ‬ ‫ﻳﮏ ﺍﺯ ﺳﮕﻤﻨﺖ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ ،‬ﺁﻏﺎﺯ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ ﺗﻮﺳﻂ ﺳﺎﻳﺮ‬ ‫ﺳﻮﺋﻴﭻ ﻫﺎ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺧﺎﺹ ﺑﺎ ﻧﺎﻡ ‪Bridge(BPUD‬‬ ‫‪ (protocol data units‬ﺑﻪ ﺍﺷﺘﺮﺍﮎ ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺳﺎﺧﺘﺎﺭ ﻳﮏ ‪BPUD‬‬ ‫ﺑﺸﺮﺡ ﺯﻳﺮ ﺍﺳﺖ ‪:‬‬

‫ ‪ . Root BID‬ﭘﺎﺭﺍﻣﺘﺮ ﻓﻮﻕ ‪ BID‬ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Root Bridge‬ﺟﺎﺭﻱ ﺭﺍ‬‫ﻣﺸﺨﺺ ﻣﻲ ﮐﻨﺪ‪.‬‬ ‫‪ . Path Cost to Bridge -‬ﻣﺴﺎﻓﺖ ‪ root bridge‬ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﺍﺩﻩ ﺍﺯ ﻃﺮﻳﻖ ﻃﻲ ﻧﻤﻮﺩﻥ ﺳﻪ ﺳﮕﻤﻨﺖ ﺑﺎ ﺳﺮﻋﺘﻲ ﻣﻌﺎﺩﻝ ‪١٠٠‬‬

‫ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﺮﺍﻱ ﺭﺳﻴﺪﻥ ﺑﻪ ‪ Root bridge‬ﺑﺎﺷﺪ ‪ ،‬ﻣﻘﺪﺍﺭ ‪ cost‬ﺑﺼﻮﺭﺕ‬ ‫)‪ (٣٨=٠+١٩+١٩‬ﺑﺪﺳﺖ ﻣﻲ ﺁﻳﺪ‪ .‬ﺳﮕﻤﻨﺘﻲ ﮐﻪ ﺑﻪ ‪ Root Bridge‬ﻣﺘﺼﻞ ﺍﺳﺖ‬

‫ﺩﺍﺭﺍﻱ ‪ Cost‬ﻣﻌﺎﺩﻝ ﺻﻔﺮ ﺍﺳﺖ‪.‬‬

‫ ‪ . Sender BID‬ﻣﺸﺨﺼﻪ ‪ BID‬ﺳﻮﺋﻴﭻ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ‪ BPDU‬ﺭﺍ ﻣﺸﺨﺺ‬‫ﻣﻲ ﮐﻨﺪ‪.‬‬ ‫‪ . Port ID -‬ﭘﻮﺭﺕ ﺍﺭﺳﺎﻝ ﮐﻨﻨﺪﻩ ‪ BPDU‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺳﻮﺋﻴﭻ ﺭﺍ ﻣﺸﺨﺺ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺗﻤﺎﻡ ﺳﻮﺋﻴﺞ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺑﻴﻦ ﺳﮕﻤﻨﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ‪،‬‬ ‫ﺑﺼﻮﺭﺕ ﭘﻴﻮﺳﺘﻪ ﺑﺮﺍﻱ ﻳﮑﺪﻳﮕﺮ ‪BPDU‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺳﻮﺋﻴﭽﻲ ﻳﮏ ‪BPDU‬‬

‫‪289‬‬

‫ﺭﺍ )ﺍﺯ ﺳﻮﺋﻴﭻ ﺩﻳﮕﺮ( ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﺩﺍﺭﺩ ﮐﻪ ﻣﻨﺎﺳﺒﺘﺮ ﺍﺯ ﺁﻥ ﭼﻴﺰﻱ ﺍﺳﺖ ﮐﻪ ﺧﻮﺩ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻫﻤﺎﻥ ﺳﮕﻤﻨﺖ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩﻩ ﺍﺳﺖ‪ BPDU ،‬ﺧﻮﺩ ﺭﺍ ﻣﺘﻮﻗﻒ ) ﺑﻪ ﺳﺎﻳﺮ‬ ‫ﺳﮕﻤﻨﺖ ﻫﺎ ﺍﺭﺍﺳﺎﻝ ﻧﻤﻲ ﻧﻤﺎﻳﺪ ( ﻭ ﺍﺯ ‪ BPDU‬ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ‬ ‫ﺳﮕﻤﻨﺖ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫•‬

‫ﻳﮏ ‪ Root bridge‬ﺑﺮ ﺍﺳﺎﺱ ﻓﺮﺁﻳﻨﺪﻫﺎﻱ ‪ BPDU‬ﺑﻴﻦ ﺳﻮﺋﻴﺞ ﻫﺎ‪ ،‬ﺍﻧﺘﺨﺎﺏ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﺑﺘﺪﺍ ﻫﺮ ﺳﻮﺋﻴﺞ ﺧﻮﺩ ﺭﺍ ﺑﻪ ﻋﻨﻮﺍﻥ ‪ Root‬ﺩﺭ ﻧﻈﺮ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ‬ ‫ﻳﮏ ﺳﻮﺋﻴﭻ ﺑﺮﺍﻱ ﺍﻭﻟﻴﻦ ﺑﺎﺭ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻳﮏ ‪ BPDU‬ﺭﺍ ﺑﻬﻤﺮﺍﻩ ‪BID‬‬

‫ﺧﻮﺩ ﮐﻪ ﺑﻪ ﻋﻨﻮﺍﻥ ‪ Root BID‬ﺍﺳﺖ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ‬

‫‪ BPDU‬ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﺩﺍﺭﻧﺪ‪ ،‬ﺁﻥ ﺭﺍ ﺑﺎ ‪ BID‬ﻣﺮﺑﻮﻃﻪ ﺍﻱ ﮐﻪ ﺑﻪ ﻋﻨﻮﺍﻥ ‪Root‬‬ ‫‪ BID‬ﺫﺧﻴﺮﻩ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ ،‬ﻣﻘﺎﻳﺴﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ‪ Root BID‬ﺟﺪﻳﺪ‬ ‫ﺩﺍﺭﺍﻱ ﻳﮏ ﻣﻘﺪﺍﺭ ﮐﻤﺘﺮ ﺑﺎﺷﺪ‪ ،‬ﺗﻤﺎﻡ ﺳﻮﺋﻴﭻ ﻫﺎ ﺁﻥ ﺭﺍ ﺑﺎ ﺁﻧﭽﻴﺰﻱ ﮐﻪ ﻗﺒﻼ" ﺫﺧﻴﺮﻩ ﮐﺮﺩﻩ‬ ‫ﺍﻧﺪ‪ ،‬ﺟﺎﻳﮕﺰﻳﻦ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ‪ Root BID‬ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺩﺍﺭﺍﻱ ﻣﻘﺪﺍﺭ‬ ‫ﮐﻤﺘﺮﻱ ﺑﺎﺷﺪ‪ ،‬ﻳﮏ ‪ BPDU‬ﺑﺮﺍﻱ ﺳﻮﺋﻴﭻ ﺟﺪﻳﺪ ﺑﻬﻤﺮﺍﻩ ‪ BID‬ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫‪Root BID‬‬

‫ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺳﻮﺋﻴﭻ ﺟﺪﻳﺪ ‪ BPDU‬ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﺩﺍﺭﺩ‪ ،‬ﺍﺯ ‪Root‬‬

‫ﺑﻮﺩﻥ ﺧﻮﺩ ﺻﺮﻓﻨﻈﺮ ﻭ ﻣﻘﺪﺍﺭ ﺍﺭﺳﺎﻟﻲ ﺭﺍ ﺑﻪ ﻋﻨﻮﺍﻥ ‪ Root BID‬ﺩﺭ ﺟﺪﻭﻝ ﻣﺮﺑﻮﻁ ﺑﻪ‬ ‫ﺧﻮﺩ ﺫﺧﻴﺮﻩ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫•‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺤﻞ ‪ ،Root Bridge‬ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ ﻣﺸﺨﺺ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ﮐﻪ‬ ‫ﮐﺪﺍﻣﻴﮏ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﺁﻧﻬﺎ ﺩﺍﺭﺍﻱ ﮐﻮﺗﺎﻫﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺑﻪ ‪ Bridge Root‬ﺍﺳﺖ‪.‬‬

‫ﭘﻮﺭﺕ ﻫﺎﻱ ﻓﻮﻕ‪ Root Ports ،‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﻫﺮ ﺳﻮﺋﻴﺞ ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺍﺭﺍﻱ ﻳﮏ‬ ‫ﻧﻤﻮﻧﻪ ﺑﺎﺷﺪ‪.‬‬ ‫•‬

‫ﺳﻮﺋﻴﭻ ﻫﺎ ﻣﺸﺨﺺ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ﮐﻪ ﭼﻪ ﮐﺴﻲ ﺩﺍﺭﺍﻱ ﭘﻮﺭﺕ ﻫﺎﻱ ‪designated‬‬

‫ﺍﺳﺖ ‪ .‬ﭘﻮﺭﺕ ﻓﻮﻕ ‪ ،‬ﺍﺗﺼﺎﻟﻲ ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ﺁﻥ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﻳﮏ‬ ‫ﺳﮕﻤﻨﺖ ﺧﺎﺹ ﺍﺭﺳﺎﻝ ﻭ ﻳﺎ ﺍﺯ ﺁﻥ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺑﺎ ﺩﺍﺷﺘﻦ ﺻﺮﻓﺎ" ﻳﮏ ﻧﻤﻮﻧﻪ‬ ‫ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﺗﻤﺎﻡ ﻣﺸﮑﻼﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Looping‬ﺑﺮﻃﺮﻑ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫‪290‬‬

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‫ﭘﻮﺭﺕ ﻫﺎﻱ ‪ designated‬ﺑﺮ ﺍﺳﺎﺱ ﮐﻮﺗﺎﻫﺘﺮﺗﻦ ﻣﺴﻴﺮ ﺑﻴﻦ ﻳﮏ ﺳﮕﻤﻨﺖ ﺗﺎ ‪root‬‬ ‫‪ bridge‬ﺍﻧﺘﺨﺎﺏ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ‪ Root bridge‬ﺩﺍﺭﺍﻱ ﻣﻘﺪﺍﺭ ﺻﻔﺮ‬

‫ﺑـــﺮﺍﻱ ‪ cost path‬ﺍﺳﺖ‪ ،‬ﻫﺮ ﭘﻮﺭﺕ ﺁﻥ ﺑﻤﻨــﺰﻟﻪ ﻳﮏ ﭘﻮﺭﺕ ‪designated‬‬ ‫ﺍﺳﺖ‪ ) .‬ﻣﺸﺮﻭﻁ ﺑﻪ ﺍﺗﺼﺎﻝ ﭘﻮﺭﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﺳﺴﮕﻤﻨﺖ ( ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ‪،‬‬

‫‪ Path Cost‬ﺑﺮﺍﻱ ﻳﮏ ﺳﮕﻤﻨﺖ ﺑﺮﺭﺳﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﻮﺭﺗﻲ ﺩﺍﺭﺍﻱ‬ ‫ﭘﺎﻳﻴﻦ ﺗﺮﻳﻦ ‪ path cost‬ﺑﺎﺷﺪ‪ ،‬ﭘﻮﺭﺕ ﻓﻮﻕ ﺑﻤﻨﺰﻟﻪ ﭘﻮﺭﺕ ‪designated‬‬

‫ﺳﮕﻤﻨﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﻭ ﻭ ﻳﺎ ﺑﻴﺶ ﺍﺯ ﺩﻭ ﭘﻮﺭﺕ ﺩﺍﺭﺍﻱ‬

‫ﻣﻘﺎﺩﻳﺮ ﻳﮑﺴﺎﻥ ‪ cost path‬ﺑﺎﺷﻨﺪ‪ ،‬ﺳﻮﺋﻴﭻ ﺑﺎ ﻣﻘﺎﺩﺭ ﮐﻤﺘﺮ ‪ BID‬ﺍﺗﺨﺎﺏ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﭘﺲ ﺍﺯ ﺍﻧﺘﺨﺎﺏ ﭘﻮﺭﺕ ‪designated‬ﺑﺮﺍﻱ ﺳﮕﻤﻨﺖ ﺷﺒﮑﻪ‪ ،‬ﺳﺎﻳﺮ ﭘﻮﺭﺕ ﻫﺎﻱ‬ ‫ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﻪ ﺳﮕﻤﻨﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻋﻨﻮﺍﻥ ‪ non -designated port‬ﺩﺭ ﻧﻈﺮ‬ ‫ﮔﺮﻓﺘﻪ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ‪ designated‬ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ‬ ‫ﻳﮏ ﺳﮕﻤﻨﺖ ﻣﺘﺼﻞ ﮔﺮﺩﻳﺪ‪.‬‬

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‫ﻫﺮ ﺳﻮﺋﻴﭻ ﺩﺍﺭﺍﻱ ﺟﺪﻭﻝ ‪ BPDU‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺑﻮﺩﻩ ﮐﻪ ﺑﺼﻮﺭﺕ ﺧﻮﺩﮐﺎﺭ ﺑﻬﻨﮕﺎﻡ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺷﺒﮑﻪ ﺑﺼﻮﺭﺕ ﻳﮏ ‪ spanning tree‬ﺑﻮﺩﻩ ﮐﻪ ‪roor‬‬

‫‪ bridge‬ﮐﻪ ﺑﻤﻨﺰﻟﻪ ﺭﻳﺸﻪ ﻭ ﺳﺎﻳﺮ ﺳﻮﺋﻴﭻ ﻫﺎ ﺑﻤﻨﺰﻟﻪ ﺑﺮﮒ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻫﺮ ﺳﻮﺋﻴﭻ‬ ‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ Root Ports‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ‪ root bridge‬ﺑﻮﺩﻩ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ‪ designated‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻫﺮ ﺳﮕﻤﻨﺖ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎ ﻭ ﺳﻮﺋﻴﭽﻴﻨﮓ ﻻﻳﻪ ﺳﻮﻡ‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻗﺒﻼ" ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﺍﮐﺜﺮ ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺭ ﻻﻳﻪ ﺩﻭﻡ ﻣﺪﻝ ‪ OSI‬ﻓﻌﺎﻟﻴﺖ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ )‪ .(Data Layer‬ﺍﺧﻴﺮﺍ" ﺑﺮﺧﻲ ﺍﺯ ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﺳﻮﻳﻴﭻ‪ ،‬ﻣﺪﻟﻲ ﺭﺍ ﻋﺮﺿﻪ‬ ‫ﻧﻤﻮﺩﻩ ﺍﻧﺪ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﻓﻌﺎﻟﻴﺖ ﺩﺭ ﻻﻳﻪ ﺳﻮﻡ ﻣﺪﻝ ‪ OSI‬ﺍﺳﺖ‪.(Network Layer) .‬‬ ‫ﺍﻳﻦ ﻧﻮﻉ ﺳﻮﺋﻴﭻ ﻫﺎ ﺩﺍﺭﺍﻱ ﺷﺒﺎﻫﺖ ﺯﻳﺎﺩﻱ ﺑﺎ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺯﻣﺎﻧﻴﮑﻪ ﺭﻭﺗﺮ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﺩﺭ ﻻﻳﻪ ﺳﻮﻡ ﺑﺪﻧﺒﺎﻝ ﺁﺩﺭﺱ ﻫﺎﻱ‬

‫ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﮔﺸﺘﻪ ﺗﺎ ﻣﺴﻴﺮ ﻣﺮﺑﻮﻁ ﺑﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﺎﻳﺪ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ MAC‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﮐﺮﺩﻥ ﺁﺩﺭﺱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ).‬ﺍﺯ ﻃﺮﻳﻖ ﻻﻳﻪ ﺩﻭﻡ( ﻣﻬﻤﺘﺮﻳﻦ ﺗﻔﺎﻭﺕ ﺑﻴﻦ ﻳﮏ ﺭﻭﺗﺮ ﻭ ﻳﮏ ﺳﻮﺋﻴﭻ ﻻﻳﻪ ﺳﻮﻡ‪،‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ ﺳﻮﻡ ﺍﺯ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺑﻬﻴﻨﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ‬

‫ﻣﻄﻠﻮﺏ ﻧﻈﻴﺮ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ ﺩﻭﻡ ﺍﺳﺖ‪ .‬ﻧﺤﻮﻩ ﺗﺼﻤﻴﻢ ﮔﻴﺮﻱ ﺁﻧﻬﺎ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺴﻴﺮﻳﺎﺑﻲ‬ ‫ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺸﺎﺑﻪ ﺭﻭﺗﺮ ﺍﺳﺖ‪ .‬ﺩﺭ ﻳﮏ ﻣﺤﻴﻂ ﺷﺒﮑﻪ ﺍﻱ ‪ ، LAN‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ‬ ‫ﺳﻮﻡ ﻣﻌﻤﻮﻻ" ﺩﺍﺭﺍﻱ ﺳﺮﻋﺘﻲ ﺑﻴﺸﺘﺮ ﺍﺯ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺨﺖ‬

‫ﺍﻓﺰﺍﺭﻫﺎﻱ ﺳﻮﺋﻴﭽﻴﻨﮓ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺳﻮﺋﻴﭻ ﻫﺎ ﺍﺳﺖ‪ .‬ﺍﻏﻠﺐ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ ﺳﻮﻡ ﺷﺮﮐﺖ‬ ‫ﺳﻴﺴﮑﻮ‪ ،‬ﺑﻤﻨﺰﻟﻪ ﺭﻭﺗﺮﻫﺎﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺑﻤﺮﺍﺗﺐ ﺍﺯ ﺭﻭﺗﺮ ﻫﺎ ﺳﺮﻳﻌﺘﺮ ﺑﻮﺩﻩ ) ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺍﺧﺘﺼﺎﺻﻲ ﺳﻮﺋﻴﭽﻴﻨﮓ ( ﻭ ﺩﺍﺭﺍﻱ ﻗﻴﻤﺖ ﺍﺭﺯﺍﻧﺘﺮﻱ ﻧﺴﺒﺖ ﺑﻪ‬ ‫ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻧﺤﻮﻩ ‪ matching Pattern‬ﻭ ‪ caching‬ﺩﺭ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ ﺳﻮﻡ‬ ‫ﻣﺸﺎﺑﻪ ﻳﮏ ﺭﻭﺗﺮ ﺍﺳﺖ‪ .‬ﺩﺭ ﻫﺮ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ﺍﺯ ﻳﮏ ﭘﺮﻭﺗﮑﻞ ﺭﻭﺗﻴﻨﮓ ﻭ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ‪ ،‬ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﻮﺋﻴﭻ ﻫﺎﻱ ﻻﻳﻪ ﺳﻮﻡ ﻗﺎﺩﺭ ﺑﻪ‬

‫ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﻣﺠﺪﺩ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺑﺼﻮﺭﺕ ﭘﻮﻳﺎ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺭﻭﺗﻴﻨﮓ ﻻﻳﻪ ﺳﻮﻡ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ ﻭ ﻫﻤﻴﻦ ﺍﻣﺮ ﺑﺎﻋﺚ ﺳﺮﻋﺖ ﺑﺎﻻﻱ ﭘﺮﺩﺍﺯﺵ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺳﻮﺋﻴﭻ‬ ‫ﻫﺎﻱ ﻻﻳﻪ ﺳﻮﻡ‪ ،‬ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺗﻮﺳﻂ ﭘﺮﻭﺗﮑﻞ ﺭﻭﺗﻴﻨﮓ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ‬ ‫ﺟﺪﺍﻭﻝ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ Caching‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻣﻼﺣﻈﻪ ﮔﺮﺩﻳﺪ‪ ،‬ﺩﺭ ﻃﺮﺍﺣﻲ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ LAN‬ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻧﻮﻉ ﺳﻮﺋﻴﭻ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‪ ،‬ﺗﺎﺛﻴﺮ ﻣﺴﺘﻘﻴﻢ ﺑﺮ ﺳﺮﻋﺖ ﻭ ﮐﻴﻔﻴﺖ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﻣﻔﻬﻮﻡ ﺭﻭﺗﻴﻨﮓ‬ ‫ﺭﻭﺗﻴﻨﮓ ) ‪ ( Routing‬ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﺷﺒﮑﻪ ﻫﺎ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻣﮑﺎﻥ ﺭﻭﺗﻴﻨﮓ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﻭﺟﻮﺩ‬ ‫ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﺪ ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪.‬‬ ‫ﺗﻌﺮﻳﻒ‬

‫ﺍﺯ ﺭﻭﺗﻴﻨﮓ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ) ‪ ( packet‬ﺍﺯ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﻭ‬

‫ﺍﺭﺳﺎﻝ ﺁﻥ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﺩﺳﺘﮕﺎﻫﻲ ﺩﻳﮕﺮ ﻭ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﻱ ﻣﺘﻔﺎﻭﺕ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺷﺒﮑﻪ ﺷﻤﺎ ﺩﺍﺭﺍﻱ ﺭﻭﺗﺮ ﻧﺒﺎﺷﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺭﻭﺗﻴﻨﮓ ﺩﺍﺩﻩ ﺑﻴﻦ ﺷﺒﮑﻪ ﺷﻤﺎ‬ ‫ﻭ ﺳﺎﻳﺮ ﺷﺒﮑﻪ ﻫﺎ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﻳﮏ ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪،‬‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺍﻃﻼﻋﺎﺕ ﺯﻳﺮ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪:‬‬

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‫ﺁﺩﺭﺱ ﻣﻘﺼﺪ‬ ‫ﺭﻭﺗﺮﻫﺎﻱ ﻣﺠﺎﻭﺭ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻧﺎﻥ ﺍﻣﮑﺎﻥ ﺍﺧﺬ ﺍﻃﻼﻋﺎﺕ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺷﺒﮑﻪ‬ ‫ﻫﺎﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ ‪.‬‬

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‫ﻣﺴﻴﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﻪ ﺗﻤﺎﻣﻲ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‬

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‫ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‬

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‫ﻧﺤﻮﻩ ﻧﮕﻬﺪﺍﺭﻱ ﻭ ﺑﺮﺭﺳﻲ ﺍﻃﻼﻋﺎﺕ ﺭﻭﺗﻴﻨﮓ‬

‫ﻫﻤﮕﺮﺍﺋﻲ ) ‪( Convergence‬‬

‫ﻓﺮﺁﻳﻨﺪ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﻬﻨﮕﺎﻡ‬

‫ﺳﺎﺯﻱ ﺟﺪﺍﻭﻝ ﺭﻭﺗﻴﻨﮓ ﻭ ﺍﻳﺠﺎﺩ ﻳﮏ ﻧﮕﺮﺵ ﺳﺎﺯﮔﺎﺭ ﺍﺯ ﺷﺒﮑﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺭ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮﻫﺎﻱ‬ ‫ﻣﻮﺟﻮﺩ ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺠﺎﻡ ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ )ﻫﻤﮕﺮﺍﺋﻲ(‪ ،‬ﺩﺍﺩﻩ ﮐﺎﺭﺑﺮ ﺍﺭﺳﺎﻝ ﻧﺨﻮﺍﻫﺪ ﺷﺪ‪.‬‬

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‫ﻣﺴﻴﺮ ﭘﻴﺶ ﻓﺮﺽ ) ‪( Default Route‬‬

‫ﻳﮏ ﻣﺴﻴﺮ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺩﺭﺝ ﺷﺪﻩ ﺩﺭ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﮐﻪ ﺑﻪ ﻋﻨﻮﺍﻥ ﺍﻭﻟﻴﻦ ﮔﺰﻳﻨﻪ ﺩﺭ ﻧﻈﺮ‬

‫ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ ‪ .‬ﻫﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﮐﻪ ﺗﻮﺳﻂ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﻪ ﻣﺴﻴﺮ‬ ‫ﭘﻴﺶ ﻓﺮﺽ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺴﻴﺮ ﻓﻮﻕ ﻣﺸﮑﻞ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﻳﮏ ﻣﺴﻴﺮ‬ ‫ﺩﻳﮕﺮ ﺍﻧﺘﺨﺎﺏ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻣﺴﻴﺮ ﺍﻳﺴﺘﺎ ) ‪( Static Route‬‬

‫ﻳﮏ ﻣﺴﻴﺮ ﺩﺍﺋﻢ ﮐﻪ ﺑﻪ ﺻﻮﺭﺕ ﺩﺳﺘﻲ ﺩﺭﻭﻥ ﻳﮏ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺩﺭﺝ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺴﻴﺮ‬

‫ﻓﻮﻕ ﺣﺘﻲ ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﺍﺭﺗﺒﺎﻁ ﻏﻴﺮ ﻓﻌﺎﻝ ﺍﺳﺖ ﺩﺭ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺑﺎﻗﻲ ﻣﺎﻧﺪﻩ ﻭ ﺻﺮﻓﺎ" ﺑﻪ‬

‫ﺻﻮﺭﺕ ﺩﺳﺘﻲ ﺣﺬﻑ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﺴﻴﺮ ﭘﻮﻳﺎ ) ‪( Dynamic Route‬‬

‫ﻳﮏ ﻣﺴﻴﺮ ﮐﻪ ﺑﻪ ﺻﻮﺭﺕ ﭘﻮﻳﺎ ) ﺍﺗﻮﻣﺎﺗﻴﮏ ( ﻭ ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﺗﻐﻴﻴﺮﺍﺕ ﺷﺒﮑﻪ ‪ ،‬ﺑﻬﻨﮕﺎﻡ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺴﻴﺮﻫﺎﻱ ﭘﻮﻳﺎ ﻧﻘﻄﻪ ﻣﻘﺎﺑﻞ ﻣﺴﻴﺮﻫﺎﻱ ﺍﻳﺴﺘﺎ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺭﻭﺗﺮﻫﺎ‪ ،‬ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺍﻧﺪ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ‬

‫ﻓﻮﻕ‪ ،‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﻧﺪ ﮐﻪ ﺍﻣﮑﺎﻥ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺟﺪﺍﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺑﻴﻦ‬ ‫ﺭﻭﺗﺮﻫﺎ ﺭﺍ ﻓﺮﺍﻫﻢ ﻧﻤﺎﻳﺪ‪ .‬ﺗﺎﮐﻨﻮﻥ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺑﺎ‬ ‫ﺍﺑﻌﺎﺩ ﮔﻮﻧﺎﮔﻮﻥ ‪ ،‬ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﺩﻭ ﻧﻮﻉ ﻋﻤﺪﻩ ﺭﻭﺗﻴﻨﮓ ‪ :‬ﭘﻮﻳﺎ ﻭ ﺍﻳﺴﺘﺎ‬

‫ﺭﻭﺗﺮ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﻣﺠﺎﻭﺭ ) ﻫﻤﺴﺎﻳﻪ( ﻭ ﻳﺎ ﺗﻮﺳﻂ ﻣﺪﻳﺮ ﺷﺒﮑﻪ‪ ،‬ﺁﮔﺎﻫﻲ ﻻﺯﻡ‬

‫ﺩﺭ ﺧﺼﻮﺹ ﺷﺒﮑﻪ ﻫﺎﻱ ﺭﺍﻩ ﺩﻭﺭ ﺭﺍ ﭘﻴﺪﺍ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺭﻭﺗﺮ ﺩﺭ ﺍﺩﺍﻣﻪ‪ ،‬ﻳﮏ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺭﺍ‬

‫ﺍﻳﺠﺎﺩ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺁﻥ ﺗﺸﺮﻳﺢ ﻧﺤﻮﻩ ﻳﺎﻓﺘﻦ ﺷﺒﮑﻪ ﻫﺎﻱ ﺭﺍﻩ ﺩﻭﺭ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺷﺒﮑﻪ‬ ‫ﻣﺴﺘﻘﻴﻤﺎ" ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺭﻭﺗﺮ ﺩﺭ ﺧﺼﻮﺹ ﺷﺒﮑﻪ‪ ،‬ﻣﺸﮑﻞ ﺧﺎﺻﻲ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺷﺒﮑﻪ ﻫﺎ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺩﺭ‬ ‫ﺧﺼﻮﺹ ﺷﺒﮑﻪ ﻫﺎﻱ ﺭﺍﻩ ﺩﻭﺭ ﺭﺍ ﭘﻴﺪﺍ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺍﺯ ﺭﻭﺗﻴﻨﮓ ﺍﻳﺴﺘﺎ )ﺩﺭﺝ ﺩﺳﺘﻲ‬

‫ﻣﺴﻴﺮﻫﺎ ﺩﺭ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺗﻮﺳﻂ ﻣﺪﻳﺮ ﺷﺒﮑﻪ( ﻭ ﻳﺎ ﺭﻭﺗﻴﻨﮓ ﭘﻮﻳﺎ )ﺩﺭﺝ ﺍﺗﻮﻣﺎﺗﻴﮏ ﻣﺴﻴـﺮﻫﺎ‬ ‫ﺩﺭ ﺟﺪﻭﻝ ﺭﻭﺗﻴــﻨﮓ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗــﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ(‪ ،‬ﺍﺳﺘــﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎ ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﻗﺪﺍﻡ ﺑﻪ ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﺍﻃﻼﻋﺎﺕ ﺧﻮﺩ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺗﻤﺎﻣﻲ ﺷﺒﮑﻪ ﻫﺎﺋﻲ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ﮐﻪ ﻧﺴﺒﺖ ﺑﻪ ﺁﻧﺎﻥ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﺭﺍ ﭘﻴﺪﺍ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺗﻐﻴﻴﺮﻱ ﺍﻳﺠﺎﺩ‬ ‫ﮔﺮﺩﺩ )ﻣﺜﻼ" ﻳﮏ ﺭﻭﺗﺮ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ ﺷﺪﻩ ﻭ ﻋﻤﻼ" ﻗﺎﺩﺭ ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻫﻲ ﻧﺒﺎﺷﺪ(‪،‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ﭘﻮﻳﺎ‪ ،‬ﺑﻪ ﺻﻮﺭﺕ ﺍﺗﻮﻣﺎﺗﻴﮏ ﺑﻪ ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺭﺍ ﺍﻃﻼﻉ‬

‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﻴﻨﮓ ﺍﻳﺴﺘﺎ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺪﻳﺮ ﺷﺒﮑﻪ ﺗﻐﻴﻴﺮﺍﺕ ﻻﺯﻡ ﺭﺍ‬

‫ﺩﺭ ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎ ‪ ،‬ﺍﻋﻤﺎﻝ ﻧﻤﺎﻳﺪ ) ﻋﺪﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ(‪.‬‬

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‫ﺩﺭ ﺭﻭﺗﻴﻨﮓ ﭘﻮﻳﺎ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﻴﻞ ﺑﻪ ﺍﻫﺪﺍﻑ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺗﺸﺨﻴﺺ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﭘﻮﻳﺎﻱ ﺭﻭﺗﺮﻫﺎ‬

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‫ﻣﺤﺎﺳﺒﻪ ﻣﺴﻴﺮﻫﺎ‬

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‫ﺗﻮﺯﻳﻊ ﺍﻃﻼﻋﺎﺕ ﺑﻬﻨﮕﺎﻡ ﺷﺪﻩ ﺭﻭﺗﻴﻨﮓ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎ‬

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‫ﺣﺼﻮﻝ ﺗﻮﺍﻓﻖ ﺑﺎ ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎ ﺩﺭ ﺧﺼﻮﺹ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺷﺒﮑﻪ‬

‫ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﺍﻳﺴﺘﺎﻱ ﺭﻭﺗﺮﻫﺎ‪ ،‬ﺍﻣﮑﺎﻥ ﻳﺎﻓﺘﻦ ﺭﻭﺗﺮﻫﺎ ﻭ ﻳﺎ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﺮﺍﻱ‬ ‫ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺁﻧﺎﻥ ﺩﺍﺩﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﺮ ﺭﻭﻱ ﺭﻭﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺗﻮﺳﻂ‬

‫ﻣﺪﻳﺮ ﺷﺒﮑﻪ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺍﺳﺖ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ﭘﻮﻳﺎ‬

‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺍﺯ ﺳﻪ ﻧﻮﻉ) ﮔﺮﻭﻩ( ﭘﺮﻭﺗﮑﻞ ﺭﻭﺗﻴﻨﮓ ﭘﻮﻳﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺗﻔﺎﻭﺕ‬

‫ﻋﻤﺪﻩ ﺑﻴﻦ ﺁﻧﺎﻥ‪ ،‬ﺭﻭﺵ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﺭﻭﺗﺮﻫﺎ ﻭ ﻣﺤﺎﺳﺒﺎﺕ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ‬ ‫ﻣﺴﻴﺮﻳﺎﺑﻲ ﺁﻧﺎﻥ ﺍﺳﺖ‪.‬‬ ‫•‬

‫‪ : Distance Vector‬ﺍﻳﻦ ﻧﻮﻉ ﺭﻭﺗﺮﻫﺎ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﻃﻼﻋﺎﺕ‬

‫ﺍﺭﺳﺎﻝ ﺷﺪﻩ ﺗﻮﺳﻂ ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎﻱ ﻣﺠﺎﻭﺭ‪ ،‬ﻣﺤﺎﺳﺒﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫‪ : Link state‬ﺍﻳﻦ ﻧﻮﻉ ﺭﻭﺗﺮﻫﺎ ﻫﺮ ﻳﮏ ﺩﺍﺭﺍﻱ ﻧﺴﺨﻪ ﺍﻱ ﺍﺯ ﺗﻤﺎﻣﻲ ﻣﭗ ﺷﺒﮑﻪ‬ ‫ﺑﻮﺩﻩ ﻭ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ ﻣﺤﺎﺳﺒﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫‪ : Hybrid‬ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ‪ Hybrid‬ﺣﺪ ﻓﺎﺻﻞ ﺑﻴﻦ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ‬ ‫ﺭﻭﺗﻴﻨﮓ ‪ state Link‬ﻭ ‪ Distance Vector‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﻓﺮﺁﻳﻨﺪ ﺭﻭﺗﻴﻨﮓ‬ ‫ﺭﻭﺗﻴﻨﮓ ) ‪ ( Routing‬ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﺷﺒﮑﻪ ﻫﺎ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻣﮑﺎﻥ ﺭﻭﺗﻴﻨﮓ ﭘﺮﻭﺗﮑﻞ ﻫﺎ ﻭﺟﻮﺩ‬ ‫ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻗﺎﺩﺭ ﺑﻪ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﻧﺨﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺑﺴﻴﺎﺭﻱ ﺍﺯ ﻋﻼﻗﻪ ﻣﻨﺪﺍﻧﻲ ﮐﻪ‬ ‫ﺟﺪﻳﺪﺍ" ﺑﻪ ﺩﻧﻴﺎﻱ ﮔﺴﺘﺮﺩﻩ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﭘﻴﻮﺳﺘﻪ ﺍﻧﺪ‪ ،‬ﻓﮑﺮ ﻣﻲ ﮐﻨﻨﺪ ﮐﻪ ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮏ ﻣﺎﺷﻴﻦ ﺻﺮﻓﺎ" ﺑﻪ ﺁﺩﺭﺱ ‪ IP‬ﺁﻥ ﻧﻴﺎﺯ ﺍﺳﺖ‪ .‬ﺑﺎ ﻣﻄﺎﻟﻌﻪ ﺍﻳﻦ ﻣﻄﻠﺐ ﻣﺸﺨﺺ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ ﮐﻪ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺑﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﻱ ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﺷﻨﺎﺋﻲ‬ ‫ﺑﺎ ﻓﺮﺁﻳﻨﺪ ﺭﻭﺗﻴﻨﮓ‪ ،‬ﻳﮏ ﻧﻤﻮﻧﻪ ﻣﺜﺎﻝ ﺭﺍ ﻣﺮﺣﻠﻪ ﺑﻪ ﻣﺮﺣﻠﻪ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩﻩ ﺗﺎ ﺑﺎ ﻓﺮﺁﻳﻨﺪ ﺭﻭﺗﻴﻨﮓ‬ ‫ﺍﻃﻼﻋﺎﺕ‪ ،‬ﺑﻴﺸﺘﺮ ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪.‬‬

‫ﻣﺜﺎﻝ ‪ :‬ﺑﺮﺭﺭﺳﻲ ﻓﺮﺁﻳﻨﺪ ﺭﻭﺗﻴﻨﮓ ﺩﺭ ﺩﻭ ﺷﺒﮑﻪ ‪LAN‬‬

‫ﺩﻭ ﺷﺒﮑﻪ ﻓﺮﺿﻲ ‪ A‬ﻭ ‪ B‬ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺭﻭﺗﺮ ) ﺭﻭﺗﺮ ‪ ( A‬ﮐﻪ ﺩﺍﺭﺍﻱ ﺩﻭ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ ٠E‬ﻭ ‪١E‬‬

‫ﻣﻲ ﺑﺎﺷﺪ ‪ ،‬ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﻣﺸﺎﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺑﺮ ﺭﻭﻱ ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺑﻮﺩﻩ ﮐﻪ ﺩﺭﻭﻥ ﺭﻭﺗﺮ ﺗﻌﺒﻴﻪ ﺷﺪﻩ ﺍﻧﺪ ) ‪ .( RJ-45‬ﮐﺎﻣﭙﻴــﻮﺗﺮ ‪A‬‬ ‫)ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ‪ ، ( A‬ﻗﺼﺪ ﺑﺮﻗﺮﺍﺭﻱ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ) B‬ﻣـﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ‬

‫ﺷﺒﮑﻪ ‪ (B‬ﺭﺍ ﺩﺍﺭﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﻳﮏ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ)ﻣﻴﺰﺑﺎﻥ(‪ A‬ﺍﺯ ﻃﺮﻳﻖ ﺧﻂ ﺩﺳﺘﻮﺭ‪ ،‬ﻓﺮﻣﺎﻥ ‪ ping 200.200.200.5‬ﺭﺍ‬

‫ﺗﺎﻳﭗ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﭘﺮﻭﺗﮑﻞ ‪ IP‬ﺑﺎ ﭘﺮﻭﺗﮑﻞ ‪) ARP‬ﺍﻗﺘﺒﺎﺱ ﺷﺪﻩ ﺍﺯ ﮐﻠﻤﺎﺕ ‪Address‬‬

‫‪ ( protocol Resolution‬ﮐﺎﺭ ﻧﻤﻮﺩﻩ ﺗﺎ ﻣﺸﺨﺺ ﮔﺮﺩﺩ ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻓﻮﻕ ﻋﺎﺯﻡ‬

‫ﭼﻪ ﺷﺒﮑﻪ ﺍﻱ ﺍﺳﺖ ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺁﺩﺭﺱ ‪ IP‬ﻭ ‪ Subnet Mask‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺑﺮﺭﺳﻲ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﺩﺭﺧﻮﺍﺳﺖ ﻓﻮﻕ ﺑﺮﺍﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍﻩ ﺩﻭﺭ ﻣﻲ ﺑﺎﺷـــﺪ‪،‬‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ) ‪ Gateway‬ﺷﺒﮑﻪ ‪ ( A‬ﺍﺭﺳﺎﻝ ﺗﺎ ﻭﻱ ﺑﺘﻮﺍﻧﺪ ﺁﻥ ﺭﺍ‬ ‫ﺑﻪ ﺷﺒﮑﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻫﺪﺍﻳﺖ ﻧﻤﺎﻳﺪ ) ﺩﺭ ﺍﻳﻦ ﻣﻮﺭﺩ ﺧﺎﺹ ﺷﺒﮑﻪ ‪.( B‬‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﺭﻭﺗﺮ‪ ،‬ﻧﻴﺎﺯﻣﻨﺪ ﺁﮔﺎﻫﻲ ﺍﺯ‬

‫ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﻭﺗﺮ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ‪ A‬ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ‪ ).‬ﻣﻨﻈﻮﺭ‬ ‫ﺁﺩﺭﺱ ‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E0‬ﺍﺳﺖ ﮐﻪ ﺷﺒﮑﻪ ‪ A‬ﺍﺯ ﻃﺮﻳﻖ ﺁﻥ ﺑﻪ ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﺷﺪﻩ‬

‫ﺍﺳﺖ ( ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺭﻳﺎﻓﺖ ﺁﺩﺭﺱ ‪ ،MAC‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﻣﺤﺘﻮﻳﺎﺕ ‪ ARP cache‬ﺧﻮﺩ ﺭﺍ‬

‫ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،Cache ARP .‬ﻣﺤﻠﻲ ﺍﺯ ﺣﺎﻓﻈﻪ ﺍﺳﺖ ﮐﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ MAC‬ﺑﺮﺍﻱ‬ ‫ﭼﻨﺪﻳﻦ ﺛﺎﻧﻴﻪ ﺩﺭ ﺁﻧﺠﺎ ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺁﺩﺭﺱ ‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﻭﺗﺮ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ‪A‬‬ ‫ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ ﺩﺭ ‪ ARP Cache‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﭘﻴﺪﺍ ﻧﺸﻮﺩ ‪ ،‬ﻧﺸﺎﻧﺪ ﻫﻨﺪﻩ ﺍﻳﻦ ﻣﻮﺿﻮﻉ‬ ‫ﺍﺳﺖ ﮐﻪ ﻣﺪﺕ ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ ﺍﺯ ﺍﺭﺗﺒﺎﻁ ﻭﻱ ﺑﺎ ﺭﻭﺗﺮ ﮔﺬﺷﺘﻪ ﻭ ﻳﺎ ﻭﻱ ﻗﺎﺩﺭ ﺑﻪ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ‬

‫‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺭﻭﺗﺮ ) ﺍﻳﻨﺘﺮﻓﻴﺴﻲ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ‪ A‬ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ ( ﻧﻤﻲ ﺑﺎﺷﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ‬ ‫ﺑﻪ ﻭﺿﻌﻴﺖ ﻓﻮﻕ ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ‪ ARP broadcast‬ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﭘﻴﺎﻡ‬ ‫ﺍﺭﺳﺎﻟﻲ ﺩﺭ ﭘﻲ ﻳﺎﻓﺘﻦ ﭘﺎﺳﺨﻲ ﻣﻨﺎﺳﺐ ﺑﺪﻳﻦ ﺳﻮﺍﻝ ﺍﺳﺖ ﮐﻪ‪ " :‬ﺁﺩﺭﺱ ‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫‪ IP:192.168.0.1‬ﭼﻴﺴﺖ ؟"‪ .‬ﭘﺲ ﺍﺯ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ‪ ،broadcast‬ﺭﻭﺗﺮ ﺗﺸﺨﻴﺺ‬

‫ﻣﻲ ﺩﻫﺪ ﮐﻪ ﺁﺩﺭﺱ ‪ IP‬ﻣﺮﺑﻮﻁ ﺑﻪ ﻭﻱ ﺑﻮﺩﻩ ﻭ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺩﺭﺧﻮﺍﺳﺖ ﻓﻮﻕ‪ ،‬ﭘﺎﺳﺦ ﺩﻫﺪ‪.‬‬ ‫ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﺭﻭﺗﺮ ﺑﺎ ﺍﺭﺳﺎﻝ ﺁﺩﺭﺱ ‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ ، E0‬ﭘﺎﺳﺦ ﻻﺯﻡ ﺭﺍ ﺑﻪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬ ‫‪298‬‬

‫ﻳﮑﻲ ﺍﺯ ﺩﻻﻳﻠﻲ ﮐﻪ ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﻗﻊ ﺩﺳﺘﻮﺭ ‪ Ping‬ﺩﺭ ﺍﻭﻟﻴﻦ ﻣﺮﺗﺒﻪ ﺑﺎ ‪Time out‬‬

‫ﻣﻮﺍﺟﻪ ﻣﻲ ﺷﻮﺩ ﺑﻪ ﻣﻮﺿﻮﻉ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺑﺮﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻣﺪﺕ ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ‬ ‫ﻃﻮﻝ ﺧﻮﺍﻫﺪ ﮐﺸﻴﺪ ﮐﻪ ﻳﮏ ‪ ARP‬ﺍﺭﺳﺎﻝ ﻭ ﻣﺎﺷﻴﻦ ﻣﺮﺑﻮﻃﻪ ﺑﺎ ﺍﺭﺳﺎﻝ ﺁﺩﺭﺱ ‪ MAC‬ﺧﻮﺩ ﺑﻪ‬ ‫ﺁﻥ ﭘﺎﺳﺦ ﺩﻫﺪ ) ‪ TTL:Time To Live‬ﺍﻭﻟﻴﻦ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ‪ Ping‬ﺑﻪ ﺳﺮ ﺁﻣﺪﻩ ﻭ ﭘﻴﺎﻡ‬ ‫‪ Time out‬ﺭﺍ ﺧﻮﺍﻫﻴﻢ ﺩﺍﺷﺖ (‪.‬‬

‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ‪ :‬ﺭﻭﺗﺮ ﺑﺎ ﺍﺭﺳﺎﻝ ﺁﺩﺭﺱ ‪ IP:192.168.0.1‬ﮐﻪ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E0‬ﺁﻥ ﻧﺴﺒﺖ‬

‫ﺩﺍﺩﻩ ﺷﺪﻩ ﺍﺳﺖ ‪ ،‬ﭘﺎﺳﺦ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ‬

‫ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﺧﺎﺭﺝ ﺍﺯ ﺷﻴﮑﻪ ﻭ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﺭﺍ ﺩﺍﺭﺍ ﻣﻲ‬ ‫ﺑﺎﺷﺪ‪ .‬ﻻﻳﻪ ﺷﺒﮑﻪ ﺑﻪ ﻻﻳﻪ ‪ DataLink‬ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺗﻮﺳﻂ ‪) Ping‬ﻳﮏ ‪ICMP‬‬ ‫‪ ( echo request‬ﺗﻮﻟﻴﺪ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ ،‬ﺑﻪ ﻫﻤﺮﺍﻩ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺭﻭﺗﺮ‪ ،‬ﺍﺷﺎﺭﻩ ﻣﻲ‬

‫ﻧﻤﺎﻳﺪ‪ .‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺷﺎﻣﻞ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ IP‬ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﺑﻪ ﻫﻤﺮﺍﻩ ‪ICMP echo‬‬ ‫ﺍﺳﺖ ﮐﻪ ﺩﺭ ﻻﻳﻪ ﺷﺒﮑﻪ ﻣﺸﺨﺺ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺷﺸﻢ ‪ :‬ﻻﻳﻪ ‪ DataLink‬ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻳﮏ ﻓﺮﻳﻢ ﺭﺍ ﺗﻮﻟﻴﺪ ﮐﻪ ﻳﮏ ﺑﺴﺘﻪ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﮐﭙﺴﻮﻟﻪ ﺷﺪﻩ ﺑﻪ ﻫﻤﺮﺍﻩ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﻣﺤﻠﻲ‬ ‫ﺍﺳﺖ ) ﺷﺒﮑﻪ ‪.( A‬ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ‪ ،‬ﺷﺎﻣﻞ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ‬ ‫) ﺁﺩﺭﺱ ‪ ( MAC‬ﻭ ﻓﻴﻠﺪ ﻧﻮﻉ ﺍﺳﺖ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﭘﺮﻭﺗﮑﻞ ﻻﻳﻪ ﺷﺒﮑﻪ‬ ‫) ﻣﺜﻼ" ‪ ( IPv4‬ﻭ ‪ ARP‬ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪ .‬ﺩﺭ ﺍﻧﺘﻬﺎﻱ ﻓﺮﻳﻢ ‪ ،‬ﺩﺭ ﺑﺨﺶ ‪ FCS‬ﻓﺮﻳﻢ‪ ،‬ﻻﻳﻪ‬

‫‪ DataLink‬ﻳﮏ ‪ CRC‬ﺭﺍ ﻣﺴﺘﻘﺮ ﻧﻤﻮﺩﻩ ﺗﺎ ﻣﺎﺷﻴﻦ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ )ﺭﻭﺗﺮ( ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺗﺸﺨﻴﺺ ﺳﺎﻟﻢ ﺑﻮﺩﻥ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭﻳﺎﻓﺘﻲ ﺑﺎﺷﺪ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﻫﻔﺘﻢ ‪ :‬ﻻﻳﻪ ‪ DataLink‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، A‬ﻓﺮﻳﻢ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻻﻳﻪ ﻓﻴﺰﻳﮑﻲ ﻗﺮﺍﺭ ﺩﺍﺩﻩ ﺗﺎ‬ ‫ﺻﻔﺮ ﻭ ﻳﮏ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺁﻥ ﺑﻪ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺩﻳﺠﻴﺘﺎﻝ ﺗﺒﺪﻳﻞ ﻭ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﻓﻴﺰﻳﮑﻲ‬ ‫ﺷﺒﮑﻪ ﺍﺭﺳﺎﻝ ﮔﺮﺩﺩ ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﻫﺸﺘﻢ ‪ :‬ﺳﻴﮕﻨﺎﻝ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E0‬ﺭﻭﺗﺮ ﺑﺮﺩﺍﺷﺘﻪ ﺷﺪﻩ ﻭ ﻓﺮﻳﻢ ﺧﻮﺍﻧﺪﻩ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺭﻭﺗﺮ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺨﺶ ‪ CRC‬ﺁﻥ ﺭﺍ ﺑﺮﺭﺳﻲ ﻭ ﺁﻥ ﺭﺍ ﺑﺎ ﻣﻘﺪﺍﺭ ‪ CRC‬ﺍﺿﺎﻓﻪ ﺷﺪﻩ ﺑﻪ‬ ‫ﻓﺮﻳﻢ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﻣﻘﺎﻳﺴﻪ ﻣﻲ ﻧﻤﺎﻳﺪ )ﺣﺼﻮﻝ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﻋﺪﻡ ﺧﺮﺍﺑﻲ ﻓﺮﻳﻢ(‪.‬‬ ‫ﻣﺮﺣﻠﻪ ﻧﻬﻢ ‪ :‬ﺩﺭ ﺍﺩﺍﻣﻪ‪ ،‬ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻣﻘﺼﺪ ) ‪ ( MAC‬ﻓﺮﻳﻢ ﺩﺭﻳﺎﻓﺘﻲ‪ ،‬ﺑﺮﺭﺳﻲ‬

‫ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﺟﻮﺩ ﻳﮏ ﻣﻮﺭﺩ ﺁﺩﺭﺱ ﮐﻪ ﺑﺎ ﺁﻥ ﻣﻄﺎﺑﻘﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ ،‬ﻓﻴﻠﺪ "ﻧﻮﻉ‬

‫ﻓﺮﻳﻢ" ﺑﺮﺭﺳﻲ ﺗﺎ ﻧﺤﻮﻩ ﺑﺮﺧﻮﺭﺩ ﺭﻭﺗﺮ ﺑﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﻣﺸﺨﺺ ﮔﺮﺩﺩ‪ IP .‬ﺩﺭ "ﻓﻴﻠﺪ ﻧﻮﻉ "‬ ‫ﺑﻮﺩﻩ ﻭ ﺭﻭﺗﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﭘﺮﻭﺗﮑﻞ ‪ IP‬ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺭﻭﺗﺮ ﺩﺭ ﺣﺎﻝ ﺍﺟﺮﺍﺀ‬ ‫ﺍﺳﺖ‪ ،‬ﻗﺮﺍﺭ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﻓﺮﻳﻢ ﺍﺯ ﻭﺿﻌﻴﺖ ﻣﻮﺟﻮﺩ ﺧﺎﺭﺝ ﻭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﻭﻟﻴﻪ ﺍﻱ ﮐﻪ‬ ‫ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺍﺳﺖ ﺩﺭ ﺑﺎﻓﺮ ﺭﻭﺗﺮ ﺫﺧﻴﺮﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻫﻢ ‪ :‬ﭘﺮﻭﺗﮑﻞ ‪ IP‬ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺁﺩﺭﺱ ‪ IP‬ﻣﻘﺼﺪ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩﻩ ﺗﺎ‬

‫ﻣﺸﺨﺺ ﮔﺮﺩﺩ ﮐﻪ ﺁﻳﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﺍﺳﺖ‪.‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺁﺩﺭﺱ ‪:IP‬‬

‫‪ ، ٢٠٠,٢٠٠,٢٠٠,٥‬ﻣﻲ ﺑﺎﺷﺪ‪ ،‬ﺭﻭﺗﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺟﺪﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺧﻮﺩ ﺗﺸﺨﻴﺺ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‬ ‫ﮐﻪ ﺁﺩﺭﺱ ﻓﻮﻕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E1‬ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﺭﻭﺗﺮ‬

‫ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﻳﺎﺯﺩﻫﻢ ‪ :‬ﺭﻭﺗﺮ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺑﺎﻓﺮ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E1‬ﻣﺴﺘﻘﺮ ﻧﻤﻮﺩﻩ ﻭ‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﻳﮏ ﻓﺮﻳﻢ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻘﺼﺪ ﺭﺍ ﺗﻮﻟﻴﺪ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺭﻭﺗﺮ ﺩﺭ ﺍﺑﺘﺪﺍ ‪ ARP Cache‬ﺧﻮﺩ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﺎﻓﺘﻦ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻣﺮﺑﻮﻁ ﺑﻪ‬

‫‪ ، IP:200.200.200.5‬ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺕ ﻋﺪﻡ ﻭﺟﻮﺩ ﺁﺩﺭﺱ ﻓﻮﻕ ﺩﺭ‬

‫‪ ، ARP cache‬ﺭﻭﺗﺮ ﻳﮏ ‪ broadcast ARP‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E1‬ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﺪﺍ‬ ‫ﻧﻤﻮﺩﻥ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻓﻮﻕ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﺍﺯﺩﻫﻢ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ B‬ﺑﺎ ﺍﺭﺍﺋﻪ ﻳﮏ ‪ ARP Reply‬ﭘﺎﺳﺦ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺁﺩﺭﺱ‬

‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﺍﻳﻨﺘﺮﻓﻴﺲ ‪E1‬‬ ‫ﺭﻭﺗﺮ ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ ﻧﻬﺎﺋﻲ ﺭﺍ ﺩﺍﺭﺍ‬

‫ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫ﻣﺮﺣﻠﻪ ﺳﻴﺰﺩﻫﻢ ‪ :‬ﻓﺮﻳﻢ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E1‬ﺭﻭﺗﺮ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ‬

‫ﻣﺒﺪﺍﺀ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ E1‬ﻭ ﺁﺩﺭﺱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻣﻘﺼﺪ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ B‬ﻣﻲ ﺑﺎﺷﺪ‪.‬ﺑﺎ ﺍﻳﻦ ﮐﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﻓﺮﻳﻢ ﺩﺭ ﻫﺮ ﻳﮏ‬ ‫ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺭﻭﺗﺮ ﺗﻐﻴﻴﺮ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ ﻫﺮﮔﺰ‬

‫ﺗﻐﻴﻴﺮ ﭘﻴﺪﺍ ﻧﻤﻲ ﻧﻤﺎﻳﺪ ) ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻫﺮﮔﺰ ﺗﻐﻴﻴﺮ ﻧﮑﺮﺩﻩ ﻭ ﺻﺮﻓﺎ" ﻓﺮﻳﻢ ﺗﻐﻴﻴﺮ ﻣﻲ ﻧﻤﺎﻳﺪ(‪.‬‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﺩﻫﻢ ‪ :‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، B‬ﻓﺮﻳﻢ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺑﺮﺭﺳﻲ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ‪ CRC‬ﺭﺍ‬

‫ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺎﺣﺼﻞ ﺑﺮﺭﺳﻲ ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﻣﻮﻓﻘﻴﺖ ﺁﻣﻴﺰ ﻧﺒﺎﺷﺪ‪ ،‬ﻓﺮﻳﻢ‬ ‫ﺩﻭﺭﺍﻧﺪﺍﺧﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‪ ،‬ﺁﺩﺭﺱ ‪ IP‬ﻣﻘﺼﺪ ﺑﺮﺭﺳﻲ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ‬ ‫ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﺑﺎ ﭘﻴﮑﺮﺑﻨﺪﻱ ‪ IP‬ﺍﻧﺠﺎﻡ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، B‬ﻣﻄﺎﺑﻘﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻓﻴﻠﺪ‬ ‫ﭘﺮﻭﺗﮑﻞ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺭﺳﻲ ﺗﺎ ﺍﻫﺪﺍﻑ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺸﺨﺺ ﮔﺮﺩﺩ‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﭘﺎﻧﺰﺩﻫﻢ ‪ :‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻳﮏ ﺩﺭﺧﻮﺍﺳﺖ ‪ICMP echo‬‬

‫ﺍﺳﺖ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ B‬ﻳﮏ ‪ ICMP echo-reply‬ﺟﺪﻳﺪ ﺭﺍ ﮐﻪ ﺷﺎﻣﻞ ﺁﺩﺭﺱ ‪ IP‬ﻣﺒﺪﺍﺀ‬

‫) ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ( B‬ﻭ ﺁﺩﺭﺱ ‪ IP‬ﻣﻘﺼﺪ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ A‬ﻣﻲ ﺑﺎﺷﺪ ﺭﺍ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ‪ ،‬ﻣﺠﺪﺩﺍ" ﻭ ﺩﺭ ﺟﻬﺖ ﻣﻌﮑﻮﺱ ﺗﮑﺮﺍﺭ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ‪ ،‬ﺁﺩﺭﺱ ﺳﺨﺖ‬ ‫ﺍﻓﺰﺍﺭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭﻃﻮﻝ ﻣﺴﻴﺮ ﺷﻨﺎﺧﺘﻪ ﺷﺪﻩ ﺑﻮﺩﻩ ﻭ ﻫﺮ ﺩﺳﺘﮕﺎﻩ‬ ‫ﺻﺮﻓﺎ" ﻧﻴﺎﺯﻣﻨﺪ ﺑﺮﺭﺳﻲ ‪ ARP cache‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺧﻮﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺸﺨﻴﺺ ﺁﺩﺭﺱ ﺳﺨﺖ‬ ‫ﺍﻓﺰﺍﺭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﻲ ﺑﺎﺷﺪ ) ﺁﺩﺭﺱ ‪.( MAC‬‬

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‫ﺭﻭﺗﺮ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﻳﮑﻲ ﺍﺯ ﺷﺎﻫﮑﺎﺭﻫﺎﻱ ﺑﺸﺮﻳﺖ ﺩﺭ ﺯﻣﻴﻨﻪ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺍﺳﺖ‪ .‬ﺑﺎ ﺍﻳﺠﺎﺩ ﺯﻳﺮ‬

‫ﺳﺎﺧﺖ ﻣﻨﺎﺳﺐ ﺍﺭﺗﺒﺎﻃﻲ‪ ،‬ﮐﺎﺭﺑﺮﺍﻥ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻗﺼﻲ ﻧﻘﺎﻁ ﺩﻧﻴﺎ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻧﺎﻣﻪ ﻫﺎﻱ‬ ‫ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ‪ ،‬ﻣﺸﺎﻫﺪﻩ ﺻﻔﺤﺎﺕ ﻭﺏ‪ ،‬ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﻓﺎﻳﻞ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﮐﻤﺘﺮ ﺍﺯ ﭼﻨﺪ‬ ‫ﺛﺎﻧﻴﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺷﺒﮑﻪ ﺍﺭﺗﺒﺎﻃﻲ ﻣﻮﺟﻮﺩ ﺑﺎ ﺑﮑﺎﺭﮔﻴﺮﻱ ﺍﻧﻮﺍﻉ ﺗﺠﻬﻴﺰﺍﺕ ﻣﺨﺎﺑﺮﺍﺗﻲ‪ ،‬ﺳﺨﺖ‬

‫ﺍﻓﺰﺍﺭﻱ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‪ ،‬ﺯﻳﺮ ﺳﺎﺧﺖ ﻣﻨﺎﺳﺐ ﺍﺭﺗﺒﺎﻃﻲ ﺭﺍ ﺑﺮﺍﻱ ﻋﻤﻮﻡ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻓﺮﺍﻫﻢ‬

‫ﺁﻭﺭﺩﻩ ﺍﺳﺖ‪ .‬ﻳﮑﻲ ﺍﺯ ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﻭ ﻣﻬﻢ ﮐﻪ ﺷﺎﻳﺪ ﺍﻏﻠﺐ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﺁﻥ ﺭﺍ ﺗﺎﮐﻨﻮﻥ‬ ‫ﻣﺸﺎﻫﺪﻩ ﻧﻨﻤﻮﺩﻩ ﺍﻧﺪ‪ ،‬ﺭﻭﺗﺮ ﺍﺳﺖ‪ .‬ﺭﻭﺗﺮﻫﺎ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺧﺎﺻﻲ ﻫﺴﺘﻨﺪ ﮐﻪ ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻫﺰﺍﺭﺍﻥ ﻣﺴــﻴﺮ ﻣﻮﺟﻮﺩ ﺑﻪ ﻣﻘﺎﺻــﺪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻫﺪﺍﻳﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ‬

‫ﺑﺮﺍﻱ ﺷﻨﺎﺧﺖ ﻋﻤﻠﮑﺮﺩ ﺭﻭﺗﺮﻫﺎ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﻳﮏ ﻣﺜﺎﻝ ﺳﺎﺩﻩ ﺷﺮﻭﻉ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪.‬‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﺑﺮﺍﻱ ﻳﮑﻲ ﺍﺯ ﺩﻭﺳﺘﺎﻥ ﺧﻮﺩ‪ ،‬ﻳﮏ ‪ E-mail‬ﺭﺍ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﻳﺪ ‪ ،‬ﭘﻴﺎﻡ ﻓﻮﻕ ﺑﻪ ﭼﻪ‬ ‫ﺻﻮﺭﺕ ﺗﻮﺳﻂ ﺩﻭﺳﺖ ﺷﻤﺎ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﮔﺮﺩﺩ ؟ ﻧﺤﻮﻩ ﻣﺴﻴﺮ ﻳﺎﺑﻲ ﭘﻴﺎﻡ ﻓﻮﻕ ﺑﻪ ﭼﻪ ﺻﻮﺭﺕ‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ ﮐﻪ ﻓﻘﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺩﻭﺳﺖ ﺷﻤﺎ ﺩﺭ ﻣﻴﺎﻥ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺩﻧﻴﺎ‪،‬‬

‫ﺁﻥ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬؟ ﺍﮐﺜﺮ ﻋﻤﻠﻴﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ﭘﻴﺎﻡ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﺩﺭﻳﺎﻓﺖ ﺁﻥ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﺗﻮﺳﻂ ﺭﻭﺗﺮ ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﻴﺮﺩ‪.‬ﺭﻭﺗﺮﻫﺎ‬

‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺧﺎﺻﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺍﻣﮑﺎﻥ ﺣﺮﮐﺖ ﭘﻴﺎﻡ ﻫﺎ ﺩﺭ ﻃﻮﻝ ﺷﺒﮑﻪ ﺭﺍ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﮔﺎﻫﻲ ﺍﺯ ﻋﻤﻠﮑﺮﺩ ﺭﻭﺗﺮ‪ ،‬ﺳﺎﺯﻣﺎﻧﻲ ﺭﺍ ﺩﺭ ﻧﻈﺮ ﺑﮕﻴﺮﻳﺪ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﺩﺍﺧﻠﻲ ﻭ ﺍﺧﺘﺼﺎﺻﻲ ﺧﻮﺩ ﺍﺳﺖ‪ .‬ﮐﺎﺭﮐﻨﺎﻥ ﺳﺎﺯﻣﺎﻥ ﻓﻮﻕ ﻫﺮ ﻳﮏ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﮐﺎﺭ ﺧﻮﺩ‬ ‫ﺍﺯ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺳﺎﺯﻣﺎﻥ ﻓﻮﻕ ﺗﻌﺪﺍﺩﻱ ﮔﺮﺍﻓﻴﺴﺖ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻣﺸﻐﻮﻝ ﺑﮑﺎﺭ‬ ‫ﻫﺴﺘﻨﺪ ﮐﻪ ﺑﮑﻤﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻃﺮﺡ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﻃﺮﺍﺣﻲ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ‬

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‫ﮔﺮﺍﻓﻴﺴﺖ ﻓﺎﻳﻠﻲ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﻫﻤﮑﺎﺭ ﺧﻮﺩ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ ،‬ﺑﺪﻟﻴﻞ ﺣﺠﻢ‬

‫ﺑﺎﻻﻱ ﻓﺎﻳﻞ ﺍﺭﺳﺎﻟﻲ‪ ،‬ﺍﮐﺜﺮ ﻇﺮﻓﻴﺖ ﺷﺒﮑﻪ ﺍﺷﻐﺎﻝ ﻭ ﺑﺪﻧﺒﺎﻝ ﺁﻥ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﮐﺎﺭﺑﺮﺍﻥ ‪ ،‬ﺷﺒﮑﻪ ﮐﻨﺪ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻋﻠﺖ ﻓﻮﻕ ) ﺗﺎﺛﻴﺮ ﻋﻤﻠﮑﺮﺩ ﻳﮏ ﮐﺎﺭﺑﺮ ﺑﺮ ﺗﻤﺎﻡ ﻋﻤﻠﮑﺮﺩ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﺳﺎﻳﺮ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ( ﺑﻪ ﻣﺎﻫﻴﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺑﺮﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﻫﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﮐﻪ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﻱ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺑﺮﺍﻱ ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻧﻴﺰ ﺍﺭﺳﺎﻝ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺁﺩﺭﺱ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭﻳﺎﻓﺖ ﺷﺪﻩ ﺭﺍ ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﮔﺎﻫﻲ ﺍﺯ ﻣﻘﺼﺪ‬ ‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺮﺭﺳﻲ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺭﻭﻳﮑﺮﺩ ﻓﻮﻕ ﺩﺭ ﺭﻓﺘﺎﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ‪ ،‬ﻃﺮﺍﺣﻲ ﻭ‬

‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺁﻧﺎﻥ ﺭﺍ ﺳﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﮔﺴﺘﺮﺵ ﺷﺒﮑﻪ ﻭ ﺍﻓﺰﺍﻳﺶ ﻋﻤﻠﻴﺎﺕ ﻣﻮﺭﺩ‬ ‫ﺍﻧﺘﻈﺎﺭ ‪ ،‬ﮐﺎﺭﺁﺋﻲ ﺷﺒﮑﻪ ﮐﺎﻫﺶ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺳﺎﺯﻣﺎﻥ ﻣﻮﺭﺩ ﻧﻈﺮ ) ﺩﺭ ﻣﺜﺎﻝ ﻓﻮﻕ ( ﺑﺮﺍﻱ‬ ‫ﺣﻞ ﻣﺸﮑﻞ ﻓﻮﻕ ﺗﺼﻤﻴﻢ ﺑﻪ ﺍﻳﺠﺎﺩ ﺩﻭ ﺷﺒﮑﻪ ﻣﺠﺰﺍ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﻳﮏ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﮔﺮﺍﻓﻴﺴﺖ ﻫﺎ‬

‫ﺍﻳﺠﺎﺩ ﻭ ﺷﺒﮑﻪ ﺩﻭﻡ ﺑﺮﺍﻱ ﺳﺎﻳﺮﮐﺎﺭﺑﺮﺍﻥ ﺳﺎﺯﻣﺎﻥ ﺩﺭ ﻧﻈﺮﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭﺍﺭﺗﺒﺎﻁ ﺩﻭ‬ ‫ﺷﺒﮑﻪ ﻓﻮﻕ ﺑﻴﮑﺪﻳﮕﺮ ﻭ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺯ ﻳﮑﺪﺳﺘﮕﺎﻩ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺭﻭﺗﺮ‪ ،‬ﺗﻨﻬﺎ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ ﮐﻪ ﺗﻤﺎﻡ ﭘﻴﺎﻣﻬﺎﻱ ﺍﺭﺳﺎﻟﻲ ﺗﻮﺳﻂ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺳﺎﺯﻣﺎﻥ‪ ،‬ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﻳﮏ‬ ‫ﮔﺮﺍﻓﻴﺴﺖ‪ ،‬ﻓﺎﻳﻠﻲ ﺑﺎ ﻇﺮﻓﻴﺖ ﺑﺎﻻ ﺭﺍ ﺑﺮﺍﻱ ﮔﺮﺍﻓﻴﺴﺖ ﺩﻳﮕﺮﻱ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ ،‬ﺭﻭﺗﺮ ﺁﺩﺭﺱ‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻓﺎﻳﻞ ﺭﺍ ﺑﺮﺭﺳﻲ ﻭ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﻓﺎﻳﻞ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ‬

‫ﮔﺮﺍﻓﻴﺴﺖ ﻫﺎ ﺩﺭ ﺳﺎﺯﻣﺎﻥ ﺍﺳﺖ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺑﺴﻤﺖ ﺷﺒﮑﻪ ﻓﻮﻕ ﻫﺪﺍﻳﺖ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﮔﺮﺍﻓﻴﺴﺖ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮﺍﻱ ﻳﮑﻲ ﺍﺯ ﭘﺮﺳﻨﻞ ﺷﺎﻏﻞ ﺩﺭ ﺑﺨﺶ ﻣﺎﻟﻲ ﺳﺎﺯﻣﺎﻥ‬ ‫ﺍﺭﺳﺎﻝ ﺩﺍﺭﺩ‪ ،‬ﺭﻭﺗﺮ ﺑﺎ ﺑﺮﺭﺳﻲ ﺁﺩﺭﺱ ﻣﻘﺼﺪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﺍﻳﻦ ﻧﮑﻨﻪ ﭘﻲ ﺧﻮﺍﻫﺪ ﺑﺮﺩ ﮐﻪ‬

‫ﭘﻴﺎﻡ ﻓﻮﻕ ﺭﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ﺍﻧﺘﻘﺎﻝ ﺩﻫﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺭﻭﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﻣﺴﻴﺮﻳﺎﺑﻲ‬ ‫ﺻﺤﻴﺢ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﻫﺪﺍﻳﺖ ﺁﻥ ﺑﻪ ﺷﺒﮑﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﻳﮑﻲ ﺍﺯ ﺍﺑﺰﺍﺭﻫﺎﺋﻲ ﮐﻪ ﺭﻭﺗﺮ ﺍﺯ ﺁﻥ ﺑﺮﺍﻱ ﺗﻌﻴﻴﻦ ﻣﻘﺼﺪ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪،‬‬

‫" ﺟﺪﻭﻝ ﭘﻴﮑﺮﺑﻨﺪﻱ " ﺍﺳﺖ‪ .‬ﺟﺪﻭﻝ ﻓﻮﻕ ﺷﺎﻣﻞ ﻣﺠﻤﻮﻋﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﺸﺮﺡ ﺫﻳﻞ ﺍﺳﺖ‪:‬‬ ‫‪304‬‬

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‫ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻧﺤﻮﻩ ﻫﺪﺍﻳﺖ ﺍﺗﺼﺎﻻﺕ ﺑﻪ ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻮﺭﺩ ﻧﻈﺮ‬

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‫ﺍﻭﻟﻮﻳﺖ ﻫﺎﻱ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﺮﺍﻱ ﻫﺮ ﺍﺗﺼﺎﻝ‬

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‫ﻗﻮﺍﻧﻴﻦ ﻣﺮﺑﻮﻁ ﺑﻪ ﺗﺒﻴﻦ ﺗﺮﺍﻓﻴﮏ ﺩﺭ ﺣﺎﻟﺖ ﻃﺒﻴﻌﻲ ﻭﺷﺮﺍﻳﻂ ﺧﺎﺹ‬

‫ﺟﺪﻭﻝ ﻓﻮﻕ ﻣﻲ ﺗﻮﺍﻧﺪ ﺳﺎﺩﻩ ﻭﻳﺎ ﺷﺎﻣﻞ ﺻﺪﻫﺎ ﺧﻂ ﺑﺮﻧﺎﻣﻪ ﺩﺭ ﻳﮏ ﺭﻭﺗﺮﻫﺎﻱ ﮐﻮﭼﮏ ﺑﺎﺷﺪ‪.‬‬ ‫ﺩﺭ ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮒ ﺟﺪﻭﻝ ﻓﻮﻕ ﭘﻴﭽﻴﺪﻩ ﺗﺮ ﺑﻮﺩﻩ ﺑﮕﻮﻧﻪ ﺍﻱ ﮐﻪ ﻗﺎﺩﺭ ﺑﻪ ﻋﻤﻠﻴﺎﺕ ﻣﺴﻴﺮﻳﺎﺑﻲ ﺩﺭ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎﺷﻨﺪ‪ .‬ﻳﮏ ﺭﻭﺗﺮ ﺩﺍﺭﺍﻱ ﺩﻭ ﻭﻇﻴﻔﻪ ﺍﺻﻠﻲ ﺍﺳﺖ‪:‬‬ ‫•‬ ‫•‬

‫ﺗﻀﻤﻴﻦ ﻋﺪﻡ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﺤﻠﻲ ﮐﻪ ﺑﻪ ﺁﻧﻬﺎ ﻧﻴﺎﺯ ﻧﻴﺴﺖ‬ ‫ﺗﻀﻤﻴﻦ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﻘﺼﺪ ﺻﺤﻴﺢ‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﻇﺎﻳﻒ ﺍﺳﺎﺳﻲ ﻓﻮﻕ‪ ،‬ﻣﻨﺎﺳﺒﺘﺮﻳﻦ ﻣﺤﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﺭﻭﺗﺮ‪ ،‬ﺍﺗﺼﺎﻝ ﺩﻭ ﺷﺒﮑﻪ‬ ‫ﺍﺳﺖ ‪ .‬ﺑﺎ ﺍﺗﺼﺎﻝ ﺩﻭ ﺷﺒﮑﻪ ﺗﻮﺳﻂ ﺭﻭﺗﺮ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺭ‬

‫ﺷﺒﮑﻪ ﺩﻳﮕﺮ ﻭ ﺑﺎﻟﻌﮑﺲ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﺗﺮﺟﻤﻪ ﻫﺎﻱ ﻻﺯﻡ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﭘﺮﻭﺗﮑﻞ‬

‫ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﻫﺮﻳﮏ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ‪ ،‬ﻧﻴﺰ ﺗﻮﺳﻂ ﺭﻭﺗﺮ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺭﻭﺗﺮ ﺷﺒﮑﻪ ﻫﺎ‬ ‫ﺭﺍ ﺩﺭ ﻣﻘﺎﺑﻞ ﻳﮑﺪﻳﮕﺮ ﺣﻔﺎﻇﺖ ﻭ ﺍﺯ ﺗﺮﺍﻓﻴﮏ ﻏﻴﺮﺿﺮﻭﺭﻱ ﭘﻴﺸﮕﻴﺮﻱ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ) .‬ﺗﺎﺛﻴﺮ ﺗﺮﺍﻓﻴﮏ‬

‫ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﺮ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ﺑﺎ ﻓﺮﺽ ﻏﻴﺮ ﻻﺯﻡ ﺑﻮﺩﻥ ﺍﻃﻼﻋﺎﺕ ﺣﺎﺻﻞ ﺍﺯ ﺗﺮﺍﻓﻴﮏ‬ ‫ﺩﺭ ﺷﺒﮑﻪ ﺍﻭﻝ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﺩﻭﻡ(‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﮔﺴﺘﺮﺵ ﺷﺒﮑﻪ‪ ،‬ﺟﺪﻭﻝ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻧﻴﺰ ﺭﺷﺪ ﻭ‬ ‫ﺗﻮﺍﻥ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺭﻭﺗﺮ ﻧﻴﺰ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻓﺰﺍﻳﺶ ﻳﺎﺑﺪ‪ .‬ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﺗﻌﺪﺍﺩ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﮐﻪ ﺑﻪ ﻳﮏ‬

‫ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻧﻮﻉ ﻭ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎ ﻣﺸﺎﺑﻪ ﺍﺳﺖ‪ .‬ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺑﻪ ﻋﻨﻮﺍﻥ ﺑﺰﺭﮔﺘﺮﻳﻦ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺯ ﻫﺰﺍﺭﺍﻥ ﺷﺒﮑﻪ ﮐﻮﭼﮑﺘﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺭﻭﺗﺮﻫﺎ‬ ‫ﺩﺭ ﺍﺗﺼﺎﻝ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮑﺘﺮ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺍﺭﺍﻱ ﻧﻘﺸﻲ ﺍﺳﺎﺳﻲ ﻭ ﺿﺮﻭﺭﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺯﻣﺎﻧﻴﮑﻪ ﺍﺯ ﻃﺮﻳﻖ ﺗﻠﻔﻦ ﺑﺎ ﺷﺨﺼﻲ ﺗﻤﺎﺳﻲ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺳﻴﺴﺘﻢ ﺗﻠﻔﻦ‪ ،‬ﻳﮏ ﻣﺪﺍﺭ‬

‫ﭘﺎﻳﺪﺍﺭ ﺑﻴﻦ ﺗﻤﺎﺱ ﮔﻴﺮﻧﺪﻩ ﻭ ﺷﺨﺺ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﻳﺠﺎﺩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﻣﺪﺍﺭ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺮﺍﺣﻞ ﻣﺘﻔﺎﻭﺗﻲ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﺴﻲ‪ ،‬ﺳﻮﺋﻴﭻ ﻫﺎ‪،‬‬

‫ﻓﻴﺒﺮ ﻫﺎﻱ ﻧﻮﺭﻱ‪ ،‬ﻣﺎﮐﺮﻭﻭﻳﻮ ﻭ ﻣﺎﻫﻮﺍﺭﻩ ﺍﻧﺠﺎﻡ ﺩﻫﺪ‪ .‬ﺗﻤﺎﻡ ﻣﺮﺍﺣﻞ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺑﺮﭘﺎﺳﺎﺯﻱ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﭘﺎﻳﺪﺍﺭ ﺑﻴﻦ ﺗﻤﺎﺱ ﮔﻴﺮﻧﺪﻩ ﻭ ﻣﺨﺎﻃﺐ ﻣﻮﺭﺩ ﻧﻈﺮ ﺩﺭ ﻣﺪﺕ ﺯﻣﺎﻥ ﺗﻤﺎﺱ ‪،‬‬ ‫ﺛﺎﺑﺖ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﮐﻴﻔﻴﺖ ﺧﻂ ﺍﺭﺗﺒﺎﻃﻲ ﻣﺸﺮﻭﻁ ﺑﻪ ﻋﺪﻡ ﺑﺮﻭﺯ ﻣﺸﮑﻼﺕ ﻓﻨﻲ ﻭ ﻏﻴﺮﻓﻨﻲ ﺩﺭ‬

‫ﻫﺮ ﻳﮏ ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﺍﺷﺎﺭﻩ ﺷﺪﻩ‪ ،‬ﺩﺭ ﻣﺪﺕ ﺑﺮﻗﺮﺍﺭﻱ ﺗﻤﺎﺱ ﺛﺎﺑــﺖ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺎ ﺑﺮﻭﺯ ﻫﺮ‬ ‫ﮔﻮﻧـﻪ ﺍﺷﮑﺎﻝ ﻧﻈﻴﺮ ﺧــــﺮﺍﺑﻲ ﻳﮏ ﺳﻮﺋﻴﭻ ﻭ ‪ ..‬ﺧﻂ ﺍﺭﺗﺒﺎﻃﻲ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮﺍﺟﻪ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ) ﺻﻔﺤﺎﺕ ﻭﺏ ‪ ،‬ﭘﻴﺎﻡ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﻭ ‪ ( ...‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﺳﻴﺴﺘﻤﻲ ﺑﺎ ﻧﺎﻡ ‪ Packet -switching network‬ﺑﻪ ﺣﺮﮐﺖ ﺩﺭ ﻣﻲ ﺁﻳﻨﺪ‪ .‬ﺩﺭ ﺳﻴﺴﺘﻢ‬ ‫ﻓﻮﻕ ‪ ،‬ﺩﺍﺩﻩ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﭘﻴﺎﻡ ﻭ ﻳﺎ ﻳﮏ ﻓﺎﻳﻞ ﺑﻪ ﺑﺴﺘﻪ ﻫﺎﻱ ‪ ١٥٠٠‬ﺑﺎﻳﺘﻲ ﺗﻘﺴﻴﻢ‬

‫ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﻓﻮﻕ ﺷﺎﻣﻞ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ‪ :‬ﺁﺩﺭﺱ ﻓﺮﺳﺘﻨﺪﻩ ‪ ،‬ﺁﺩﺭﺱ‬

‫ﮔﻴﺮﻧﺪﻩ‪ ،‬ﻣﻮﻗﻌﻴﺖ ﺑﺴﺘﻪ ﺩﺭ ﭘﻴﺎﻡ ﻭ ﺑﺮﺭﺳﻲ ﺍﺭﺳﺎﻝ ﺩﺭﺳﺖ ﺍﻃﻼﻋﺎﺕ ﺗﻮﺳﻂ ﮔﻴﺮﻧﺪﻩ ﺍﺳﺖ‪ .‬ﻫﺮ‬ ‫ﻳﮏ ﺍﺯ ﺑﺴﺘﻪ ﻫﺎﻱ ﻓﻮﻕ ﺭﺍ ‪ Packet‬ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺴﺘﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﻬﺘﺮﻳﻦ‬

‫ﻭ ﻣﻨﺎﺳﺒﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺑﺮﺍﻱ ﻣﻘﺼﺪ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺳﻴﺴﺘﻢ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺗﻠﻔﻦ ﭘﻴﭽﻴﺪﻩ ﺗﺮ ﺑﻨﻈﺮ ﻣﻲ ﺁﻳﺪ‪ ،‬ﻭﻟﻲ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻣﺒﺘﻨﻲ ﺑﺮ ﺩﺍﺩﻩ ﺩﻭﺩﻟﻴﻞ‬ ‫) ﻣﺰﻳﺖ( ﻋﻤﺪﻩ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ‪ Packet switching‬ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪:‬‬ ‫•‬

‫ﺷﺒﮑﻪ ﻗﺎﺩﺭ ﺑﻪ ﺗﻨﻈﻴﻢ ﻟﻮﺩ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺍﺳﺖ‬

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‫ﺩﺭ ﺻﻮﺭﺕ ﻭﺟﻮﺩ ﺍﺷﮑﺎﻝ ﺩﺭ ﻳﮏ ﺩﺳﺘﮕﺎﻩ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻣﺴﻴﺮ ﺩﻳﮕﺮ ﻋﺒﻮﺭ ﺩﺍﺩﻩ‬

‫) ﻣﻴﻠﻲ ﺛﺎﻧﻴﻪ (‬

‫ﺷﺪﻩ ﺗﺎ ﺑﻪ ﻣﻘﺼﺪ ﺑﺮﺳﺪ‪.‬‬

‫ﺭﻭﺗﺮﻫﺎ ﮐﻪ ﺑﺨﺶ ﺍﺻﻠﻲ ﺷﺒﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺗﺸﮑﻴﻞ ﻣﻲ ﺩﻫﻨﺪ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ " ﭘﻴﮑﺮﺑﻨﺪﻱ ﻣﺠﺪﺩ ﻣﺴﻴﺮ‬ ‫" ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﺷﺮﺍﻳﻂ ﺣﺎﮐﻢ ﺑﺮ ﺧﻄﻮﻁ ﻧﻈﻴﺮ ﺗﺎﺧﻴﺮ ﺩﺭ‬ ‫ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﻭ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻋﻨﺎﺻﺮ ﻣﺘﻔﺎﻭﺕ ﺷﺒﮑﻪ ﺑﺼﻮﺭﺕ ﺩﺍﺋﻢ‬

‫ﻣﻮﺭﺩ ﺑﺮﺭﺳﻲ ﻗﺮﺍﺭ ﺧﻮﺍﻫﻨﺪ ﮔﺮﻓﺖ‪ .‬ﺭﻭﺗﺮ ﺩﺍﺭﺍﻱ ﺍﻧﺪﺍﺯﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪:‬‬ ‫‪306‬‬

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‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﺍﻣﮑﺎﻥ ‪ Internet connection sharing‬ﺑﻴﻦ ﺩﻭ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺁﻧﻬﺎ ﻭﻳﻨﺪﻭﺯ ‪ ٩٨‬ﻧﺼﺐ ﺷﺪﻩ ﺍﺳﺖ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ ،‬ﻳﮑﻲ ﺍﺯ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﮐﻪ ﺧﻂ ﺍﻳﻨﺘﺮﻧﺖ ﺑﻪ ﺁﻥ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﺳﺖ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﺭﻭﺗﺮ ﺳﺎﺩﻩ ﺭﻓﺘﺎﺭ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﻣﺪﻝ ﻓﻮﻕ ﺭﻭﺗﺮ‪ ،‬ﻋﻤﻠﻴﺎﺕ ﺳﺎﺩﻩ ﺍﻱ ﺭﺍ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪ .‬ﺩﺍﺩﻩ ﻣﻮﺭﺩ ﻧﻈﺮ‬ ‫ﺑﺮﺭﺳﻲ ﺗﺎ ﻣﻘﺼﺪ ﺁﻥ ﺑﺮﺍﻱ ﻳﮑﻲ ﺍﺯ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺗﻌﻴﻴﻦ ﮔﺮﺩﺩ‪.‬‬

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‫ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮔﺘﺮ ﻧﻈﻴﺮ ﺭﻭﺗﺮﻫﺎﺋﻲ ﮐﻪ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﮐﻮﭼﮏ ﺭﺍ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ ،‬ﻋﻤﻠﻴﺎﺕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﻱ ﺭﺍ ﻧﺴﺒﺖ ﺑﻪ ﻣﺪﻝ ﻗﺒﻠﻲ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎﻱ ﻓﻮﻕ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﻗﻮﺍﻧﻴﻦ ﺍﻣﻨﻴﺘﻲ ﺣﺎﮐﻢ ﺑﺮ ﺳﺎﺯﻣﺎﻥ ﻣﺮﺑﻮﻃﻪ ﺗﺒﻌﻴﺖ ﻭ‬

‫ﺑﺼﻮﺭﺕ ﺍﺩﻭﺍﺭﻱ ﺳﻴﺴﺘﻢ ﺍﻣﻨﻴﺘﻲ ﺗﺒﻴﻦ ﺷﺪﻩ ﺍﻱ ﺭﺍ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮔﺘﺮ ﻣﺸﺎﺑﻪ ﺭﻭﺗﺮﻫﺎﺋﻲ ﮐﻪ ﺗﺮﺍﻓﻴﮏ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺩﺭ ﻧﻘﻂ ﺣﺴﺎﺱ ﻭﻣﻬﻢ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﮐﻨﺘﺮﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﻣﺴﻴﺮﻳﺎﺑﻲ‬

‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺩﺭ ﺍﻏﻠﺐ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﻣﺘﻮﺳﻂ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺳﺎﺯﻣﺎﻧﻬﺎ ﺍﺯ‬

‫ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺩﻭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺳﺎﺯﻣﺎﻥ ﺍﺯ ﻃﺮﻳﻖ ﺭﻭﺗﺮ ﺑﻪ‬

‫ﺷﺒﮑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺳﺎﺯﻣﺎﻥ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺧﻂ ﺍﺗﺮﻧﺖ‬ ‫) ﻳﮏ ﺍﺗﺼﺎﻝ ‪ ، ٩ base-T١٠٠‬ﺧﻂ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ‪ ١٠٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺑﻮﺩﻩ ﻭ‬ ‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﻫﺸﺖ ﺭﺷﺘﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ( ﺑﻪ ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺭﻭﺗﺮ ﺑﻪ ﻣﺮﮐﺰ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺧﺪﻣﺎﺕ ﺍﻳﻨﺘﺮﻧﺖ )‪ (ISP‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺧﻄﻮﻁ‬

‫ﺍﺧﺘﺼﺎﺻﻲ ﺑﺎ ﺳﺮﻋﺖ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﺧﻂ ﺍﺧﺘﺼﺎﺻﻲ ‪ T1‬ﻳﮏ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ‬ ‫ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﺑﻮﺩﻩ ﻭ ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ‪ ١,٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﻣﻮﺳﺴﺎﺕ ﺑﺎ ﺗﻮﺟﻪ‬

‫ﺑﻪ ﺣﺴﺎﺳﻴﺖ ﻭ ﻧﻮﻉ ﮐﺎﺭ ﺧﻮﺩ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺍﺯ ﻳﮏ ﺧﻂ ﺩﻳﮕﺮ ﻧﻴﺰ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺭﻭﺗﺮ ﺑﺎ‬ ‫‪ ISP‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺧﻂ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ‪ Backup‬ﺑﻮﺩﻩ ﻭ ﺑﻤﺤﺾ ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ ﺩﺭ ﺧﻂ ﺍﺧﺘﺼﺎﺻﻲ) ﻣﺜﻼ"‪( T1‬‬

‫ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺧﻂ ﺩﻭﻡ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺧﻂ ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﻣﻮﻗﺖ ﻭ ﺩﺭ ﻣﻮﺍﻗﻊ‬ ‫ﺍﺿﻄﺮﺍﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﺧﻂ ﺑﺎ ﺳﺮﻋﺖ ﭘﺎﻳﻴﻦ ﺗﺮﺭﺍ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬

‫ﺭﻭﺗﺮﻫﺎ ﻋﻼﻭﻩ ﺑﺮ ﻗﺎﺑﻠﻴﺖ ﺭﻭﺗﻴﻨﮓ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻳﮏ ﻧﻘﻄﻪ ﺑﻪ ﻧﻘﻄﻪ ﺩﻳﮕﺮ‪ ،‬ﺩﺍﺭﺍﻱ‬

‫ﺍﻣﮑﺎﻧﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺳﻴﺴﺘﻢ ﺍﻣﻨﻴﺘﻲ ﻧﻴﺰ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﻣﻲ ﺗﻮﺍﻥ ﻣﺸﺨﺺ ﮐﺮﺩ‬ ‫ﮐﻪ ﻧﺤﻮﻩ ﺩﺳﺘﻴﺎﺑﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺧﺎﺭﺝ ﺍﺯ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺳﺎﺯﻣﺎﻥ ﺑﻪ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺑﻪ ﭼﻪ‬

‫ﺻﻮﺭﺕ ﺍﺳﺖ ‪ .‬ﺍﮐﺜﺮ ﺳﺎﺯﻣﺎﻧﻬﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺩﺍﺭﺍﻱ ﻳﮏ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻭ ﻳﺎ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺧﺎﺹ‬ ‫ﻓﺎﻳﺮﻭﺍﻝ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻋﻤﺎﻝ ﺳﻴﺎﺳــﺖ ﻫﺎﻱ ﺍﻣﻨﻴﺘﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻗﻮﺍﻧــﻴﻦ ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺩﺭ ﺟﺪﻭﻝ‬ ‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺍﺯ ﻟﺤﺎﻅ ﺍﻣﻨﻴﺘﻲ ﺩﺍﺭﺍﻱ ﺻﻼﺑﺖ ﺑﻴﺸﺘﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﻳﮑﻲ ﺍﺯ ﻋﻤﻠﻴﺎﺕ ﺍﺩﻭﺍﺭﻱ ) ﺗﮑﺮﺍﺭﻱ ( ﮐﻪ ﻫﺮ ﺭﻭﺗﺮ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪ ،‬ﺁﮔﺎﻫﻲ ﺍﺯ ﺍﺳﺘﻘﺮﺍﺭ ﻳﮏ‬

‫ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ‬ ‫ﺩﺍﺧﻠﻲ ﺑﻮﺩﻩ ﻧﻴﺎﺯﻱ ﺑﻪ ﺭﻭﺕ ﻧﻤﻮﺩﻥ ﺁﻥ ﺗﻮﺳﻂ ﺭﻭﺗﺮ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺯ‬

‫ﻣﮑﺎﻧﻴﺰﻣﻲ ﺑﺎ ﻧﺎﻡ ‪ Subnet mask‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ subnet .‬ﻣﺸﺎﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ‪IP‬‬ ‫ﺑﻮﺩﻩ ﻭ ﺍﻏﻠﺐ ﺑﺼﻮﺭﺕ ‪ ٢٥٥,٢٥٥,٢٥٥,٠‬ﺍﺳﺖ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﻪ ﺭﻭﺗﺮ ﺍﻋﻼﻡ ﻣﻲ ﻧﻤﺎﻳﺪ ﮐﻪ‬ ‫ﺗﻤﺎﻡ ﭘﻴﺎﻡ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﻳﺎ ﮔﻴﺮﻧﺪﻩ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﻣﺸﺘﺮﮎ ﺩﺭ ﺳﻪ ﮔﺮﻭﻩ‬

‫ﺍﻭﻝ ﻣﻲ ﺑﺎﺷﻨﺪ ‪ ،‬ﻣﺮﺑﻮﻁ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ ﻣﺸﺎﺑﻪ ﺑﻮﺩﻩ ﻭ ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﺭﺳﺎﻝ ﺁﻧﻬﺎ ﺑﺮﺍﻱ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺩﻳﮕﺮ ﻭﺟﻮﺩ ﻧﺪﺍﺭﺩ‪.‬‬

‫ﻣﺜﻼ" ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺎ ﺁﺩﺭﺱ ‪ ١٥,٥٧,٣١,٤٠‬ﭘﻴﺎﻣﻲ ﺭﺍ ﺑﺮﺍﻱ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﺎ ﺁﺩﺭﺱ‬ ‫‪ ١٥,٥٧,٣١,٥٢‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﺭﻭﺗﺮ ﮐﻪ ﺩﺭ ﺟﺮﻳﺎﻥ ﺗﻤﺎﻡ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺖ‪ ،‬ﺳﻪ‬ ‫ﮔﺮﻭﻩ ﺍﻭﻝ ﺩﺭ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﺮﺳﺘﻨﺪﻩ ﻭ ﮔﻴﺮﻧﺪﻩ ﺭﺍ ﻣﻄﺎﺑﻘﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ﻭ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺑﺮ‬ ‫ﺭﻭﻱ ﺷﺒﮑﻪ ﺩﺍﺧﻠﻲ ﻧﮕﻪ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﺁﮔﺎﻫﻲ ﺍﺯ ﻣﻘﺼﺪ ﻳﮏ ﭘﻴﺎﻡ‬

‫ﺭﻭﺗﺮ ﻳﮑﻲ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﻫﺎﺏ‪،‬‬ ‫ﺳﻮﺋﻴﭻ ﻭ ﺭﻭﺗﺮ ﺳﻴﮕﻨﺎﻝ ﻫﺎﺋﻲ ﺭﺍ ﺍﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﻫﺎ ﺩﺭﻳﺎﻓﺖ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺮﺍﻱ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻭ ﻳﺎ ﺷﺒﮑﻪ ﻫﺎﻱ ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﻧﺪ‪ .‬ﺭﻭﺗﺮ ﺗﻨﻬﺎ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺟﻮﺩ ﻣﻲ ﺑﺎﺷﺪ ﮐﻪ‬

‫ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﻣﺴﻴﺮ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺗﺼﻤﻴﻢ ﮔﻴﺮﻱ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ‬ ‫ﻓﻮﻕ ‪ ،‬ﺭﻭﺗﺮﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﻧﺴﺒﺖ ﺑﻪ ﺩﻭ ﻣﻮﺿﻮﻉ ﺁﮔﺎﻫﻲ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ :‬ﺁﺩﺭﺱ ﻫﺎ ﻭ ﺳﺎﺧﺘﺎﺭ‬ ‫ﺷﺒﮑﻪ‪.‬‬

‫ﺯﻣﺎﻧﻴﮑﻪ ﺗﻮﺳﻂ ﻳﮑﻲ ﺍﺯ ﺩﻭﺳﺘﺎﻧﺘﺎﻥ ﺑﺮﺍﻱ ﺷﻤﺎ ﻳﮏ ﮐﺎﺭﺕ ﺗﺒﺮﻳﮏ ﺳﺎﻝ ﻧﻮ ﺍﺭﺳﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ‪،‬‬ ‫ﺍﺯ ﺁﺩﺭﺳﻲ ﻣﻄﺎﺑﻖ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ " :‬ﺗﻬﺮﺍﻥ‪ -‬ﺧﻴﺎﺑﺎﻥ ﺍﻳﺮﺍﻥ ‪ -‬ﮐﻮﭼﻪ ﺷﻤﻴﺮﺍﻧﺎﺕ‪ -‬ﭘﻼﮎ‬ ‫‪ " ١١٠‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﺑﺨﺶ ﺑﻮﺩﻩ ﮐﻪ ﺑﻪ ﺍﺩﺍﺭﻩ ﭘﺴﺖ ﻣﺮﺑﻮﻃﻪ ﺍﻣﮑﺎﻥ ﭘﻴﺪﺍ ﻧﻤﻮﺩﻥ‬

‫ﺁﺩﺭﺱ ﻓﻮﻕ ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺪ ﭘﺴﺘﻲ ﺑﺎﻋﺚ ﺳﺮﻋﺖ ﺩﺭ ﺍﺭﺳﺎﻝ ﮐﺎﺭﺕ ﺗﺒﺮﻳﮏ ﻭ‬ ‫ﺩﺭﻳﺎﻓﺖ ﺁﻥ ﺗﻮﺳﻂ ﺷﺨﺺ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻲ ﻧﻤﺎﻳﺪ ‪.‬ﻭﻟﻲ ﺣﺘﻲ ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﮐﺪ ﭘﺴﺘﻲ ﻫﻢ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﺸﻮﺩ ‪ ،‬ﺍﻣﮑﺎﻥ ﺩﺭﻳﺎﻓﺖ ﮐﺎﺭﺕ ﺗﺒﺮﻳﮏ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺸﺨﺺ ﺷﺪﻥ ﺷﻬﺮﺳﺘﺎﻥ ‪ ،‬ﺧﻴﺎﺑﺎﻥ‬ ‫‪ ،‬ﮐﻮﭼﻪ ﻭ ﭘﻼﮎ ﻧﻴﺰ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﺁﺩﺭﺱ ﻓﻮﻕ ﻳﮏ ﻧﻮﻉ ﺁﺩﺭﺱ ﻣﻨﻄﻘﻲ ﺍﺳﺖ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺭﻭﺷﻲ ﺭﺍ ﺑﺮﺍﻱ ﺩﺭﻳﺎﻓﺖ ﮐﺎﺭﺕ‬ ‫ﺗﺒﺮﻳﮏ ‪ ،‬ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﻣﺮﺗﺒﻂ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬

‫ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﮐﻪ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺁﺩﺭﺱ ﻓﻮﻕ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﺑﻮﺩﻩ ﻭ ﺗﻮﺳﻂ ﺩﺳﺘﮕﺎﻫﻲ ﮐﻪ ﺑﻪ ﮐﺎﺑﻞ ﺷﺒﮑﻪ ﻣﺘﺼﻞ‬ ‫ﺍﺳﺖ‪ ،‬ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﮐﺎﺭﺕ ﺷﺒﮑﻪ‬ ‫)‪ (NIC‬ﻣﻲ ﺑﺎﺷﺪ‪ ،‬ﮐﺎﺭﺕ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﺩﺍﺋﻤﻲ ﺑﻮﺩﻩ ﮐﻪ ﺩﺭ ﻳﮏ ﻣﺤﻞ‬ ‫ﺧﺎﺹ ﺍﺯ ﺣﺎﻓﻈﻪ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺍﺳﺖ ‪ .‬ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﮐﻪ ﺁﺩﺭﺱ ‪Media Access ( MAC‬‬ ‫‪ (Control‬ﻧﻴﺰ ﻧﺎﻣﻴﺪﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﺩﺍﺭﺍﻱ ﺩﻭ ﺑﺨﺶ ﺑﻮﺩﻩ ﮐﻪ ﻫﺮ ﻳﮏ ﺳﻪ ﺑﺎﻳﺖ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺍﻭﻟﻴﻦ ﺳﻪ ﺑﺎﻳﺖ‪ ،‬ﺷﺮﮐﺖ ﺳﺎﺯﻧﺪﻩ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﺩﻭﻣﻴﻦ ﺳﻪ ﺑﺎﻳﺖ ﻳـﮏ‬

‫ﺷﻤﺎﺭﻩ ﺳﺮﻳﺎﻝ ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬ ‫‪309‬‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﺁﺩﺭﺱ ﻣﻨﻄﻘﻲ ﺩﺭ ﻳﮏ ﻟﺤﻈﻪ ﺑﺎﺷﺪ‪ .‬ﻭﺿﻌﻴﺖ ﻓﻮﻕ‬

‫ﺩﺭﺭﺍﺑﻄﻪ ﺑﺎ ﺍﺷﺨﺎﺹ ﻧﻴﺰ ﺻﺪﻕ ﻣﻲ ﮐﻨﺪ‪ .‬ﻣﺜﻼ" ﻳﮏ ﺷﺨﺺ ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﻱ ﺁﺩﺭﺱ ﭘﺴﺘﻲ‪،‬‬ ‫ﺷﻤﺎﺭﻩ ﺗﻠﻔﻦ‪ ،‬ﺁﺩﺭﺱ ﭘﺴﺖ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﻭ ‪ ...‬ﺑﺎﺷﺪ‪ .‬ﺍﺯ ﻃﺮﻳﻖ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺍﻣﮑﺎﻥ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﺷﻤﺎ ﻭﺟﻮﺩ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺁﺩﺭﺱ ﻫﺎﻱ ﻣﻨﻄﻘﻲ ﺩﺭ ﮐﺎﻣﭙﻴﻮﻧﺮ ﻧﻴﺰ ﻣﺸﺎﺑﻪ‬

‫ﺳﻴﺴﺘﻢ ﻓﻮﻕ ﮐﺎﺭ ﻣﻲ ﮐﻨﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺳﺘﺎ ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺁﺩﺭﺱ ﺩﻫﻲ ﻭ ﻳﺎ‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺑﻄﻮﺭ ﻫﻤﺰﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ‪ ،‬ﺷﻤﺎ ﺩﺍﺭﺍﻱ ﻳﮏ ﺁﺩﺭﺱ ﺑﻮﺩﻩ ﮐﻪ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﻣﺸﺘﻖ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ‬

‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﺒﮑﻪ ﮐﻮﭼﮏ ﻣﻲ ﺑﺎﺷﻴﺪ ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ‪NetBEUI‬‬

‫ﻣﺎﻳﮑﺮﻭﺳﺎﻓﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ .‬ﺑﻬﺮﺣﺎﻝ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻲ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﺁﺩﺭﺱ‬ ‫ﻣﻨﻄﻘﻲ ﺑﻮﺩﻩ ﮐﻪ ﭘﺮﻭﺗﮑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻗﺎﻟﺐ ﺁﺩﺭﺱ ﻓﻮﻕ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ ﻳﮏ ﮐﺎﻣﭙﻴﻮﻧﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﻳﮏ ﺁﺩﺭﺱ ﻣﻨﻄﻘﻲ ﺗﺒﺪﻳﻞ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺁﺩﺭﺱ‬ ‫ﻣﻨﻄﻘﻲ ﺩﺭ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﺍﻱ ﻣﺸﺎﻫﺪﻩ ﺁﺩﺭﺱ‬

‫ﻓﻴﺰﻳﮑﻲ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺧﻮﺩ ﻣﻲ ﺗﻮﺍﻧﻴﺪ ﺍﺯ ﺩﺳﺘﻮﺭ ‪ ) IPCONFIG‬ﻭﻳﻨﺪﻭﺯ ‪٢٠٠٠‬ﻭ ‪ (XP‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻧﻤﺎﻳﺪ‪.‬‬

‫ﭘﺮﻭﺗﮑﻞ ﻫﺎ‬

‫ﺍﻭﻟﻴﻦ ﻭ ﻣﻬﻤﺘﺮﻳﻦ ﻭﻇﻴﻔﻪ ﺭﻭﺗﺮ‪ ،‬ﺁﮔﺎﻫﻲ ﺍﺯ ﻣﺤﻠﻲ ﺍﺳﺖ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﻃﻼﻋﺎﺕ ﺍﺭﺳﺎﻝ‬

‫ﮔﺮﺩﻧﺪ‪.‬‬ ‫‪310‬‬

‫ﺍﮐﺜﺮ ﺭﻭﺗﺮﻫﺎ ﮐﻪ ﻳﮏ ﭘﻴﺎﻡ ﺭﺍ ﺑﺮﺍﻱ ﺷﻤﺎ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﺯ ﺁﺩﺭﺱ ﻓﻴﺰﻳﮑﻲ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﻤﺎ ﺁﮔﺎﻫﻲ ﻧﺪﺍﺭﻧﺪ‪ .‬ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺷﻨﺎﺧﺖ ﺍﮐﺜﺮ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺭﺍﻳﺞ ‪ ،‬ﺑﺮﻧﺎﻣﻪ‬

‫ﺭﻳﺰﻱ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺭﻭﺗﺮﻫﺎ ﻧﺴﺒﺖ ﺑﻪ ﻓﻮﺭﻣﺖ ﻫﺮ ﻳﮏ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﺁﺩﺭﺱ ﺩﻫﻲ‬ ‫ﺩﺍﺭﺍﻱ ﺷﻨﺎﺧﺖ ﻣﻨﺎﺳﺐ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ) .‬ﺗﻌﺪﺍﺩ ﺑﺎﻳﺖ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺮ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺁﮔﺎﻫﻲ‬ ‫ﺍﺯ ﻧﺤﻮﻩ ﺍﺭﺳﺎﻝ ﺩﺭﺳﺖ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﻘﺼﺪ ﻭ ‪ (...‬ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﻬﻤﺘﺮﻳﻦ ﻋﻨﺎﺻﺮ ﺩﺭ‬

‫ﺍﻳﺠﺎﺩ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﻳﻨﺘﺮﻧﺖ ﻣﻄﺮﺡ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺭﻭﺗﺮﻫﺎ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺭﺍ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﻣﻘﺼﺪ ﻣﻮﺭﺩ ﻧﻈﺮ‪ ،‬ﺗﻨﻬﺎ ﻭﻇﻴﻔﻪ ﻳﮏ‬

‫ﺭﻭﺗﺮ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺭﻭﺗﺮﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺎﺩﺭ ﺑﻪ ﻳﺎﻓﺘﻦ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﻣﻤﮑﻦ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭﻳﮏ‬

‫ﺷﺒﮑﻪ ﭘﻴﺸﺮﻓﺘﻪ ﻫﺮ ﭘﻴﺎﻡ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺑﻪ ﭼﻨﺪﻳﻦ ﺑﺨﺶ ﮐﻮﭼﮑﺘﺮ ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺨﺶ ﻫﺎﻱ‬ ‫ﻓﻮﻕ ﺑﺼﻮﺭﺕ ﻣﺠﺰﺍ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭ ﻣﻘﺼﺪ ﻣﺠﺪﺩﺍ" ﺑﺎ ﺗﺮﮐﻴﺐ ﺑﺨﺶ ﻫﺎﻱ ﻓﻮﻕ ﺑﻴﮑﺪﻳﮕﺮ‪ ،‬ﭘﻴﺎﻡ‬

‫ﺍﻭﻟﻴﻪ ﺷﮑﻞ ﻭﺍﻗﻌﻲ ﺧﻮﺩ ﺭﺍ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺨﺶ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ‪Packet‬‬

‫ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﻫﺮ ﻳﮏ ﺍﺯﺁﻧﺎﻥ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺍﺯ ﻳﮏ ﻣﺴﻴﺮ ﺧﺎﺹ ﺍﺭﺳﺎﻝ ﮔﺮﺩﻧﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ‬ ‫ﻫﺎ ﺭﺍ ‪ network Packet-Switched‬ﻣﻲ ﮔﻮﻳﻨﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﻳﮏ ﻣﺴﻴﺮ‬

‫ﺍﺧﺘﺼﺎﺻﻲ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻓﺮﺳﺘﻨﺪﻩ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻭ ﮔﻴﺮﻧﺪﻩ ﺍﻳﺠﺎﺩ ﻧﺨﻮﺍﻫﺪ ﮔﺮﺩﻳﺪ‪ .‬ﭘﻴﺎﻡ‬

‫ﻫﺎﻱ ﺍﺭﺳﺎﻟﻲ ﺍﺯ ﻃﺮﻳﻖ ﻳﮑﻲ ﺍﺯ ﻫﺰﺍﺭﺍﻥ ﻣﺴﻴﺮ ﻣﻤﮑﻦ ﺣﺮﮐﺖ ﺗﺎ ﺩﺭ ﻧﻬﺎﻳﺖ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﮔﻴﺮﻧﺪﻩ ‪ ،‬ﺩﺭﻳﺎﻓﺖ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺭ ﺑﺮﺧﻲ ﺣﺎﻻﺕ‬ ‫ﻋﻨﺎﺻﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻟﻮﺩ ﺑﺎﻻﺋﻲ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻨﺪ‪ ،‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺭﻭﺗﺮﻫﺎ ﺑﺎ ﻳﮑﺪﻳﮕﺮ‬ ‫ﺍﺭﺗﺒﺎﻁ ﻭ ﺗﺮﺍﻓﻴﮏ ﺷﺒﮑﻪ ﺭﺍ ﺑﻬﻴﻨﻪ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ‪ ) .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺴﻴﺮﻫﺎﻱ ﺩﻳﮕﺮ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺑﺎﺗﻮﺟﻪ ﺑﻪ ﻭﺟﻮﺩ ﺗﺮﺍﻓﻴﮏ ﺑﺎﻻ ﺩﺭ ﺑﺨﺶ ﻫﺎﻱ ﺧﺎﺻﻲ ﺍﺯ ﺷﺒﮑﻪ(‬ ‫ﺭﺩﻳﺎﺑﻲ ﻳﮏ ﭘﻴﺎﻡ‬ ‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭﻳﻨﺪﻭﺯ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ ‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺳﺘﻮﺭ‬ ‫‪ Traceroute‬ﻣﻲ ﺗﻮﺍﻧﻴﺪ ﻣﺴﻴﺮ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﻧﺒﺎﻝ ﻧﻤﺎﺋﻴﺪ‪.‬‬

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‫ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﺑﺎﺗﻮﺟﻪ ﺑﻪ ﮔﺴﺘﺮﺩﮔﻲ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻭﺟﻮﺩ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﻣﺴﻴﺮﻳﺎﺑﻲ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺍﺳﺘﻔﺎﺩﻩ ﺷﻮﺩ‪ .‬ﺭﻭﺗﺮ ﺳﺮﻱ ‪١٢٠٠٠‬‬ ‫ﺳﻴﺴﮑﻮ ﻳﮑﻲ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﺭﻭﺗﺮﻫﺎ ﺑﻮﺩﻩ ﮐﻪ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﺻﻠﻲ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺗﮑﻨﻮﻟﻮﮊﻱ ﺑﮑﺎﺭ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺩﺭ ﻃﺮﺍﺣﻲ ﺭﻭﺗﺮﻫﺎﻱ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ﺳﻮﭘﺮ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‬ ‫ﻣﻲ ﺑﺎﺷﺪ‪ ) .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻫﺎﻱ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺑﻬﻤﺮﺍﻩ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺳﻮﻳﺌﭻ ﻫﺎﻱ ﭘﺮ‬ ‫ﺳﺮﻋﺖ (‪ .‬ﺩﺭ ﺭﻭﺗﺮ ﻣﺪﻝ ‪ ١٢٠٠٠‬ﺍﺯ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻫﺎﻱ ‪ MHZ MIPS R5000٢٠٠‬ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﺷﻮﺩ‪ ، ١٢٠١٦ .‬ﻳﮑﻲ ﺍﺯ ﻣﺪﻝ ﻫﺎﻱ ﺳﺮﻱ ﻓﻮﻕ ﺍﺳﺖ ‪ .‬ﻣﺪﻝ ﻓﻮﻕ ﻗﺎﺩﺭ ﺩﺍﺭﺍﻱ ﺗﻮﺍﻥ‬ ‫ﻋﻤﻠﻴﺎﺕ ‪ ٣٢٠‬ﻣﻴﻠﻴﺎﺭﺩ ﺑﻴﺖ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺩﺭ ﺛﺎﻧﻴﻪ ﺭﺍ ﺩﺍﺭﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺪﻝ ﻓﻮﻕ ﺑﺎ‬

‫ﺗﻤﺎﻡ ﺗﻮﺍﻥ ﻭ ﻇﺮﻓﻴﺖ ﺧﻮﺩ ﻧﺼﺐ ﮔﺮﺩﺩ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﻧﺘﻘﺎﻝ‪ ٦٠‬ﻣﻴﻠﻴﻮﻥ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻫﺮﺛﺎﻧﻴﻪ ﺭﺍ‬ ‫ﺩﺍﺭﺍ ﺍﺳﺖ‪.‬‬

‫ﺭﻭﺗﺮﻫﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺟﺪﻭﻝ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺧﻮﺩ ﻗﺎﺩﺭ ﺑﻪ ﻣﺴﻴﺮﻳﺎﺑﻲ ﺻﺤﻴﺢ ﺑﺴﺘﻪ ﻫﺎﻱ‬

‫ﺍﻃﻼﻋﺎﺗﻲ ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ .‬ﻗﻮﺍﻧﻴﻦ ﻣﻮﺟﻮﺩ ﺩﺭ ﺟﺪﻭﻝ ﻓﻮﻕ ﺳﻴﺎﺳﺖ ﻣﺴﻴﺮﻳﺎﺑﻲ ﻳﮏ ﺑﺴﺘﻪ‬ ‫ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺗﺒﻴﻦ ﺧﻮﺍﻫﻨﺪ ﮐﺮﺩ ‪ .‬ﻗﺒﻞ ﺍﺯ ﺍﺭﺳﺎﻝ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﻣﺴﻴﺮ ﻣﺸﺨﺺ‬ ‫ﺷﺪﻩ ‪ ،‬ﺭﻭﺗﺮ ﺧﻂ ) ﻣﺴﻴﺮ ( ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺍﺯ ﺍﺯ ﻧﻘﻄﻪ ﻧﻈﺮ ﮐﺎﺭﺁﺋﻲ ﺑﺮﺭﺳﻲ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺴﻴﺮ ﻓﻮﻕ ﻓﺎﻗﺪ ﮐﺎﺭﺁﺋﻲ ﻻﺯﻡ ﺑﺎﺷﺪ‪ ،‬ﺭﻭﺗﺮ ﻣﺴﻴﺮ ﻓﻮﻕ ﺭﺍ ﭼﺸﻢ ﭘﻮﺷﻲ ﻧﻤﻮﺩﻩ ﻭ‬

‫ﻣﺠﺪﺩﺍ" ﻳﮏ ﻣﺴﻴﺮ ﺩﻳﮕﺮ ﺭﺍ ﻣﺸﺨﺺ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﮐﺎﺭﺁﺋﻲ ﻣﺴﻴﺮ ﻣﺸﺨﺺ‬ ‫ﺷﺪﻩ ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺗﻮﺳﻂ ﻣﺴﻴﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﺪ ﮔﺮﺩﻳﺪ‪ .‬ﺗﻤﺎﻡ ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ‬ ‫ﺻﺮﻓﺎ" ﺩﺭ ﮐﺴﺮﻱ ﺍﺯ ﺛﺎﻧﻴﻪ ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﻣﻴﻠﻴﻮﻥ ﻫﺎ ﻣﺮﺗﺒﻪ ﺗﮑﺮﺍﺭ‬ ‫ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﺁﮔﺎﻫﻲ ﺍﺯ ﻣﺤﻠﻲ ﮐﻪ ﭘﻴﺎﻡ ﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺭﺳﺎﻝ ﮔﺮﺩﻧﺪ ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﻭﻇﻴﻔﻪ ﻳﮏ ﺭﻭﺗﺮ‬ ‫ﺍﺳﺖ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﺳﺎﺩﻩ‪ ،‬ﺻﺮﻓﺎ" ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩﻩ ﻭ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ‬ ‫ﺭﻭﺗﺮﻫﺎ ﻋﻤﻠﻴﺎﺕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﻭ ﭘﻴﭽﻴﺪﻩ ﺗﺮﻱ ﺭﺍ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ‪.‬‬

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‫ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ‬ ‫ﺭﻭﺗﺮ ﻳﻚ ﻧﻮﻉ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺧﺎﺹ ﺍﺳﺖ ﻛﻪ ﺩﺍﺭﺍﻱ ﻋﻨﺎﺻﺮ ﻣﺸﺎﺑﻪ ﻳﻚ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‬ ‫ﺷﺨﺼﻲ ﻧﻈﻴﺮ ﭘﺮﺩﺍﺯﻧﺪﻩ‪ ،‬ﺣﺎﻓﻈﻪ‪ ،‬ﺧﻄﻮﻁ ﺩﺍﺩﻩ ﻭ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﻠﻒ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ‬ ‫ﺍﺳﺖ‪ .‬ﺭﻭﺗﺮﻫﺎ ﻧﻴﺰ ﻫﻤﺎﻧﻨﺪ ﻛﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻛﻪ ﺑﺮﺍﻱ ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎ ﺑﻪ ﻳﻚ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻧﻴﺎﺯ‬

‫ﺩﺍﺭﻧﺪ‪ ،‬ﺍﺯ ﺧﺪﻣﺎﺕ ﻳﻚ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺩﺭ ﺍﺑﻌﺎﺩ ﮔﺴﺘﺮﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻓﺮﺁﻳﻨﺪ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺑﺎ ﺍﺳﺘﻘﺮﺍﺭ ﺑﺮﻧﺎﻣﻪ ‪ ، Bootstrap‬ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭ ﻳﻚ ﻓﺎﻳﻞ‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺭ ﺣﺎﻓﻈﻪ ﺁﻏﺎﺯ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ﺭﻭﺗﺮ ﻧﺘﻮﺍﻧﺪ ﻳﻚ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﺍ ﭘﻴﺪﺍ‬

‫ﻧﻤﺎﻳﺪ‪ Setup mode ،‬ﻓﻌﺎﻝ ﻭ ﭘﺲ ﺍﺯ ﺍﺗﻤﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺩﺭ ﺍﻳﻦ ‪ ، mode‬ﻣﻲ ﺗﻮﺍﻥ ﻳﻚ‬ ‫ﻧﺴﺨﻪ ‪ backup‬ﺍﺯ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﺍ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ NVRAM‬ﺫﺧﻴﺮﻩ ﻧﻤﻮﺩ‪.‬‬ ‫ﻫﺪﻑ ﺍﺯ ﺍﺟﺮﺍﻱ ﺭﻭﺗﻴﻦ ﻫﺎﻱ ﺭﺍﻩ ﺍﻧﺪﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ ، IOS‬ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻭ ﺁﻏﺎﺯ ﻓﻌﺎﻟﻴﺖ ﻫﺎﻱ ﻳﻚ‬ ‫ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻻﺯﻡ ﺍﺳﺖ ﻋﻤﻠﻴﺎﺕ ﺯﻳﺮ ﺗﻮﺳﻂ ﺭﻭﺗﻴﻦ ﻫﺎﻱ ﺭﺍﻩ ﺍﻧﺪﺍﺯ ﺍﻧﺠﺎﻡ‬ ‫ﺷﻮﺩ ‪:‬‬ ‫•‬

‫ﺣﺼﻮﻝ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ ﻋﻤﻠﻜﺮﺩ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺭﻭﺗﺮ‬

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‫ﻳﺎﻓﺘﻦ ﻭ ﺍﺳﺘﻘﺮﺍﺭ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ IOS‬ﺩﺭ ﺣﺎﻓﻈﻪ‬

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‫ﻳﺎﻓﺘﻦ ﻭ ﺑﻜﺎﺭﮔﻴﺮﻱ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﺍﻩ ﺍﻧﺪﺍﺯ ﻭ ﻳﺎ ﻭﺭﻭﺩ ﺑﻪ ‪setup mode‬‬

‫ﭘﺲ ﺍﺯ ﺭﻭﺷﻦ ﻛﺮﺩﻥ ﺭﻭﺗﺮ‪ ،‬ﺩﺭ ﺍﻭﻟﻴﻦ ﺍﻗﺪﺍﻡ ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﻣﻮﺳﻮﻡ ﺑﻪ ‪ ) POST‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ‬

‫‪ ( power-on self-test‬ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ ROM‬ﺫﺧﻴﺮﻩ ﻭ‬ ‫ﻣﺸﺘﻤﻞ ﺑﺮ ﺭﻭﺗﻴﻦ ﻫﺎﺋﻲ ﺍﺳﺖ ﻛﻪ ﺗﻤﺎﻣﻲ ﻋﻨﺎﺻﺮ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺭﻭﺗﺮ ﻧﻈﻴﺮ ﭘﺮﺩﺍﺯﻧﺪﻩ ‪ ،‬ﺣﺎﻓﻈﻪ‬ ‫ﻭ ﭘﻮﺭﺕ ﻫﺎﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﻜﻪ ﺭﺍ ﺑﺮﺭﺳﻲ ﻭ ﺗﺴﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﭘﺲ ﺍﺯ ﺣﺼﻮﻝ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﺻﺤﺖ ﻋﻤﻠﻜﺮﺩ ﺳﺨﺖ ﺍﻓﺰﺍﺭ‪ ،‬ﻓﺮﺁﻳﻨﺪ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺑﺮ ﺍﺳﺎﺱ‬

‫ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺩﻧﺒﺎﻝ ﻣﻲ ﺷﻮﺩ‪:‬‬

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‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ :‬ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ‪ loader bootstrap‬ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﺎﻓﻈﻪ‬ ‫‪ . ROM‬ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﻣﺸﺘﻤﻞ ﺑﺮ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺴﺖ‬ ‫ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻭ ﻣﻘﺪﺍﺭﺩﻫﻲ ﺍﻭﻟﻴﻪ ‪ IOS‬ﺑﺮﺍﻱ ﺍﻧﺠﺎﻡ ﻭﻇﺎﻳﻒ ﻣﺤﻮﻟﻪ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫•‬

‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ :‬ﻳﺎﻓﺘﻦ ﻣﺤﻞ ﺫﺧﻴﺮﻩ ‪ . IOS‬ﻓﻴﻠﺪ ﺑﻮﺕ ﺭﻳﺠﺴﺘﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ‪ ،‬ﻣﻜﺎﻥ‬ ‫ﺫﺧﻴﺮﻩ ‪ IOS‬ﺭﺍ ﺗﻌﻴﻴﻦ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ﻣﺸﺨﺺ ﺷﺪﻩ ﺑﺎﺷﺪ ﻛﻪ ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫‪ IOS‬ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺩﺭ ﺣﺎﻓﻈﻪ ﻣﺴﺘﻘﺮ ﮔﺮﺩﺩ ﻭﻟﻲ ‪ IOS‬ﺩﺭ ﺣﺎﻓﻈﻪ ﻓﻠﺶ‬ ‫ﻣﻮﺟﻮﺩ ﻧﺒﺎﺷﺪ ‪ ،‬ﻳﻚ ﻧﺴﺨﻪ ﺍﺯ ‪ IOS‬ﺑﺎ ﺍﻣﻜﺎﻧﺎﺕ ﻣﺤﺪﻭﺩﺗﺮ ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﻓﻈﻪ ‪ROM‬‬ ‫ﺩﺭ ﺣﺎﻓﻈﻪ ﻣﺴﺘﻘﺮ ﺧﻮﺍﻫﺪ ﺷﺪ ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ :‬ﺍﺳﺘﻘﺮﺍﺭ ‪ IOS image‬ﺩﺭ ﺣﺎﻓﻈﻪ ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ‪ IOS‬ﺩﺭ‬ ‫ﺣﺎﻓﻈﻪ ﻣﺴﺘﻘﺮ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﺲ ﺍﺯ ﺍﺳﺘﻘﺮﺍﺭ ‪ IOS‬ﺩﺭ ﺣﺎﻓﻈﻪ ﻭ ﻋﻤﻠﻴﺎﺗﻲ ﺷﺪﻥ ﺁﻥ‪ ،‬ﻟﻴﺴﺘﻲ‬

‫ﺍﺯ ﻋﻨﺎﺻﺮ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻧﻤﺎﻳﺸﮕﺮ )ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ‬

‫ﺗﺮﻣﻴﻨﺎﻝ( ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺍﺳﺘﻘﺮﺍﺭ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺭ ﺣﺎﻓﻈﻪ ﻭ ﺍﺟﺮﺍﻱ ﺩﺳﺘﻮﺭﺍﺕ ﺁﻥ ‪ .‬ﺩﺭ‬ ‫ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ ، NVRAM‬ﺩﺭﻭﻥ ﺣﺎﻓﻈﻪ ﺍﺻﻠﻲ‬

‫ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﻭ ﺩﺳﺘﻮﺭﺍﺕ ﺁﻥ ﻳﻜﻲ ﭘﺲ ﺍﺯ ﺩﻳﮕﺮﻱ ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ :‬ﻓﻌﺎﻝ ﺷﺪﻥ ‪ mode Setup‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ‪ IOS‬ﺑﮕﻮﻧﻪ ﺍﻱ‬ ‫ﺗﻨﻈﻴﻢ ﺷﺪﻩ ﺑﺎﺷﺪ ﻛﻪ ﻭﻱ ﺭﺍ ﻣﻠﺰﻡ ﺑﻪ ﺍﺳﺘﻘﺮﺍﺭ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﺯ ﻃﺮﻳﻖ ﻳﻚ ﺳﺮﻭﻳﺲ‬

‫ﺩﻫﻨﺪﻩ ‪ TFTP‬ﻭ ﻳﺎ ‪ NVRAM‬ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﺩﺭ ﻋﻤﻞ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺭ ﻫﻴﭽﻴﻚ ﺍﺯ‬ ‫ﻣﻜﺎﻥ ﻫﺎﻱ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﻣﻮﺟﻮﺩ ﻧﺒﺎﺷﺪ‪ ،‬ﺭﻭﺗﻴﻦ ‪ automated setup‬ﻣﻘﺪﺍﺭﺩﻫﻲ‬ ‫ﺍﻭﻟﻴﻪ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ‪ mode‬ﺍﻣﻜﺎﻧﺎﺕ ﻭ ﺗﺴﻬﻴﻼﺕ ﻻﺯﻡ ﺑﺮﺍﻱ ﻧﺼﺐ ﺣﺪﺍﻗﻞ‬

‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻣﺪﻳﺮﻳﺖ ﺷﺒﻜﻪ ﮔﺬﺍﺷﺘﻪ ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ‪setup‬‬ ‫‪ ، mode‬ﭘﺎﺳﺦ ﻫﺎﻱ ﭘﻴﺶ ﻓﺮﺽ ﺑﻴﻦ ﻋﻼﻣﺖ ][ ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﺷﺪﻩ ﻭ ﭘﺲ ﺍﺯ ﻓﺸﺮﺩﻥ‬ ‫ﻛﻠﻴﺪ ‪ ،Enter‬ﮔﺰﻳﻨﻪ ﭘﻴﺶ ﻓﺮﺽ ﺍﻧﺘﺨﺎﺏ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﺲ ﺍﺯ ﺗﻜﻤﻴﻞ ﻓﺮﺁﻳﻨﺪ‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ‪ ،‬ﮔﺰﻳﻨﻪ ﻫﺎﻱ ﺯﻳﺮ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪:‬‬ ‫‪314‬‬

‫‪Setup mode‬‬ ‫‪[0] Go to the IOS command prompt‬‬ ‫‪without saving this config.‬‬ ‫‪[1] Return back to the setup without‬‬ ‫‪saving this config.‬‬ ‫‪[2] Save this configuration to nvram‬‬ ‫‪and exit.‬‬ ‫‪Enter your selection [2]:‬‬ ‫ﭼﺮﺍﻍ ﻫﺎﻱ ‪LEDs‬‬ ‫ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ‪ ،‬ﻫﺮ ‪ LED‬ﻣﻮﺟﻮﺩ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺭﺳﺎﻟﺖ ﺧﻮﺩ ﻣﻲ ﺗﻮﺍﻧﺪ ﺍﻃﻼﻋﺎﺕ‬

‫ﻣﻔﻴﺪﻱ ﺭﺍ ﺍﺭﺍﺋﻪ ﻧﻤﺎﻳﺪ‪ .‬ﻣﺜﻼ" ‪ LED‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ‪ ،‬ﻭﺿﻌﻴﺖ ﻫﺮ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﺍ ﻧﺸﺎﻥ‬

‫ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻓﻌﺎﻝ ﻭ ﺑﻪ ﺩﺭﺳﺘﻲ ﻣﺘﺼﻞ ﺷﺪﻩ ﺑﺎﺷﺪ ﻭﻟﻲ ‪ LED‬ﺁﻥ‬ ‫ﺧﺎﻣﻮﺵ ﺍﺳﺖ‪ ،‬ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﺮﺍﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻳﻚ ﻣﺸﻜﻞ ﺧﺎﺹ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺑﺎﺷﺪ‪.‬‬ ‫ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺳﻴﺴﺘﻢ ﻭ ﻧﻤﺎﻳﺶ ﭘﻴﺎﻡ ﻫﺎ ﻭ ﺍﻃﻼﻋﺎﺕ ﻣﺨﺘﻠﻒ‬

‫ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺍﻃﻼﻋﺎﺕ ﻭ ﭘﻴﺎﻡ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺑﺮ ﺭﻭﻱ ﻧﻤﺎﻳﺸﮕﺮ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ‬ ‫ﺗﺮﻣﻴﻨﺎﻝ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻓﻮﻕ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﻭﺗﺮ ﻭ ﻧﺴﺨﻪ ‪IOS‬‬

‫ﻣﺘﻔﺎﻭﺕ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺧﻲ ﺍﺯ ﭘﻴﺎﻡ ﻫﺎ ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺍﺷﺎﺭﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻧﻤﺎﻳﺶ ﭘﻴﺎﻡ "‪,NVRAM invalid‬‬

‫‪possibly due to write‬‬

‫‪ "erase‬ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺭﺍ ﺍﻋﻼﻡ ﻣﻲ ﻧﻤﺎﻳﺪ ﻛﻪ ﺭﻭﺗﺮ ﺗﺎﻛﻨﻮﻥ‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﻧﺸﺪﻩ ﻭ ﻳﺎ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ NVRAM‬ﺁﻥ ﺣﺬﻑ ﺷﺪﻩ ﺍﺳﺖ‬ ‫‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻻﺯﻡ ﺍﺳﺖ ﻛﻪ ﺭﻭﺗﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺪﻩ ﻭ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺭ ﺣﺎﻓﻈﻪ‬ ‫‪ NVRAM‬ﺫﺧﻴﺮﻩ ﻭ ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﺯ ﻓﺎﻳﻞ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ .‬ﺗﻨﻈﻤﻴﺎﺕ ﭘﻴﺶ ﻓﺮﺽ ﺑﺮﺍﻱ‬ ‫ﺭﻳﺠﺴﺘﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻣﻘﺪﺍﺭ ‪ X2102٠‬ﻣﻲ ﺑﺎﺷﺪ ﻛﻪ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺫﺧﻴﺮﻩ ‪image IOS‬‬

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‫ﺩﺭ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺍﺳﺖ ﻭ ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺑﻪ ﺩﺭﻭﻥ ﺣﺎﻓﻈﻪ ﺍﺻﻠﻲ‬

‫ﻣﻨﺘﻘﻞ ﮔﺮﺩﺩ ‪.‬‬ ‫•‬

‫ﻧﻤﺎﻳﺶ ﺍﻃﻼﻋﺎﺕ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻭ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺭﻭﺗﺮ ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ‪،‬‬

‫ﺍﻃﻼﻋﺎﺕ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ ﺷﻤﺎﺭﻩ ﻧﺴﺨﻪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ‪ ، IOS ، bootstrap‬ﻣﺪﻝ‬ ‫ﺭﻭﺗﺮ‪ ،‬ﻧﻮﻉ ﭘﺮﺩﺍﺯﻧﺪﻩ‪ ،‬ﻣﻴﺰﺍﻥ ﺣﺎﻓﻈﻪ‪ ،‬ﺗﻌﺪﺍﺩ ﻭ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﺑﺮ ﺭﻭﻱ ﺻﻔﺤﻪ‬ ‫ﻧﻤﺎﻳﺸﮕﺮ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﺗﺮﻣﻴﻨﺎﻝ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺭﻭﺗﺮ‬ ‫‪) IOS‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ ،( Internetwork Operating System‬ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺍﺳﺖ ﻛﻪ‬ ‫ﺍﺯ ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﻛﻨﺘﺮﻝ ﺭﻭﺗﻴﻨﮓ ﻭ ﺳﻮﺋﻴﭽﻴﻨﮓ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺑﻴﻦ ﺷﺒﻜﻪ ﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ‪ IOS‬ﺑﺮﺍﻱ ﺗﻤﺎﻣﻲ ﻣﺪﻳﺮﺍﻥ ﺷﺒﻜﻪ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺪﻳﺮﻳﺖ ﻭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺳﺘﮕﺎﻩ ﻫﺎﺋﻲ‬ ‫ﻧﻈﻴﺮ ﺭﻭﺗﺮ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺍﻟﺰﺍﻣﻲ ﺍﺳﺖ‪.‬‬

‫ﺩﺭ ﺍﻳﻦ ﻣﻄﻠﺐ ﭘﺲ ﺍﺯ ﻣﻌﺮﻓﻲ ﺍﻭﻟﻴﻪ ‪ IOS‬ﺑﻪ ﺑﺮﺭﺳﻲ ﺑﺮﺧﻲ ﺍﺯ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺁﻥ ﺧﻮﺍﻫﻴﻢ‬ ‫ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫‪ IOS‬ﻭ ﺿﺮﻭﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺁﻥ‬

‫ﻳﻚ ﺭﻭﺗﺮ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﻳﻚ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺠﺎﻡ ﻭﻇﺎﻳﻒ ﺧﻮﺩ ﻧﻤﻲ‬ ‫ﺑﺎﺷﻨﺪ)ﻫﻤﺎﻧﻨﺪ ﻳﻚ ﻛﺎﻣﭙﻴﻮﺗﺮ (‪ .‬ﺷﺮﻛﺖ ﺳﻴﺴﻜﻮ‪ ،‬ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ‪ Cisco IOS‬ﺭﺍ ﺑﺮﺍﻱ ﻃﻴﻒ‬

‫ﮔﺴﺘﺮﺩﻩ ﺍﻱ ﺍﺯ ﻣﺤﺼﻮﻻﺕ ﺷﺒﻜﻪ ﺍﻱ ﺧﻮﺩ ﻃﺮﺍﺣﻲ ﻭ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬ ‫ﻓﻮﻕ‪ ،‬ﺟﺰﺀ ﻻﻳﻨﻔﻚ ﺩﺭ ﻣﻌﻤﺎﺭﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ ﻣﻲ ﺑﺎﺷﺪ ﻭ ﻫﻤﭽﻨﻴﻦ ﺑﻪ ﻋﻨﻮﺍﻥ‬ ‫ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺩﺭ ﺳﻮﺋﻴﭻ ﻫﺎﻱ ‪ Catalyst‬ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﻳﻚ ﺳﻴﺴﺘﻢ‬ ‫ﻋﺎﻣﻞ ‪ ،‬ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻗﺎﺩﺭ ﺑﻪ ﺍﻧﺠﺎﻡ ﻫﻴﭽﮕﻮﻧﻪ ﻋﻤﻠﻴﺎﺗﻲ ﻧﺨﻮ ﺍﻫﺪ ﺑﻮﺩ ‪ ) .‬ﻋﺪﻡ ﺗﺎﻣﻴﻦ ﺷﺮﺍﻳﻂ‬ ‫ﻻﺯﻡ ﺑﺮﺍﻱ ﺑﺎﻟﻔﻌﻞ ﺷﺪﻥ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ(‪.‬‬ ‫‪ ، IOS‬ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺷﺒﻜﻪ ﺍﻱ ﺯﻳﺮ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪:‬‬ ‫•‬

‫ﻋﻤﻠﻴﺎﺕ ﺭﻭﺗﻴﻨﮓ ﻭ ﺳﻮﺋﻴﭽﻴﻨﮓ‬

‫•‬

‫ﺩﺳﺘﻴﺎﺑﻲ ﺍﻳﻤﻦ ﻭ ﻣﻄﻤﺌﻦ ﺑﻪ ﻣﻨﺎﺑﻊ ﺷﺒﻜﻪ‬

‫•‬

‫ﻗﺎﺑﻠﻴﺖ ﺗﻮﺳﻌﻪ ﻭ ﺗﻐﻴﻴﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺒﻜﻪ‬

‫ﻣﺎﻫﻴﺖ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪IOS‬‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ IOS‬ﺍﺯ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺧﻂ ﺩﺳﺘﻮﺭﻱ ﻭ ﻳﺎ ‪ ) CLI‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪command-‬‬ ‫‪ ( line interface‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ IOS .‬ﻳﻚ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻛﻠﻴﺪﻱ ﺍﺳﺖ ﻛﻪ ﺍﺯ ﺁﻥ ﺩﺭ‬

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‫ﺍﻛﺜﺮ ﺧﻄﻮﻁ ﺗﻮﻟﻴﺪ ﻣﺤﺼﻮﻻﺕ ﺷﺮﻛﺖ ﺳﻴﺴﻜﻮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﻋﻤﻠﻜﺮﺩ ‪ IOS‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ‬

‫ﻧﻮﻉ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺑﻴﻦ ﺷﺒﻜﻪ ﺍﻱ ﻣﺘﻔﺎﻭﺕ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﺤﻴﻂ ‪ IOS‬ﺍﺯ ﺭﻭﺵ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫‪ : session console‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺍﺗﺼﺎﻝ ﺳﺮﻳﺎﻝ ﺑﺎ ﺳﺮﻋﺖ‬ ‫ﭘﺎﺋﻴﻦ‪ ،‬ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﺩﺳﺘﮕﺎﻩ ﺗﺮﻣﻴﻨﺎﻝ ﺭﺍ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ﻣﺘﺼﻞ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ) .‬ﺳﺮﻭﻳﺲ ﺷﺒﻜﻪ ﺍﻱ ﺧﺎﺻﻲ ﺑﺮ ﺭﻭﻱ ﺭﻭﺗﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻧﺸﺪﻩ ﺍﺳﺖ(‬

‫•‬

‫ﺍﺭﺗﺒﺎﻁ ‪ : Dialup‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻮﺩﻡ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ﻛﻤﻜﻲ‬

‫) ‪ ( AUX‬ﺑﺎ ﺭﻭﺗﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﮔﺮﺩﺩ ‪ ) .‬ﺳﺮﻭﻳﺲ ﺷﺒﻜﻪ ﺍﻱ ﺧﺎﺻﻲ ﺑﺮ ﺭﻭﻱ‬

‫ﺭﻭﺗﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻧﺸﺪﻩ ﺍﺳﺖ (‪.‬‬ ‫•‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ : telnet‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ ﻣﻲ ﺑﺎﻳﺴﺖ ﺣﺪﺍﻗﻞ ﻳﻜﻲ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﺑﺎ ﻳﻚ‬

‫ﺁﺩﺭﺱ ‪ IP‬ﭘﻴﻜﺮﺑﻨﺪﻱ ﮔﺮﺩﺩ ﻭ ‪ terminal sessions virtual‬ﺑﺮﺍﻱ ‪ login‬ﻭ‬ ‫ﺭﻣﺰ ﻋﺒﻮﺭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺪﻩ ﺑﺎﺷﺪ‪.‬‬

‫ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ ﺭﻭﺗﺮ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺍﺯ ﻳﻚ ﺑﺮﻧﺎﻣﻪ ﺗﺮﻣﻴﻨﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‬ ‫‪ HyperTerminal‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﮔﺰﻳﻨﻪ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺣﺎﻻﺕ ﻣﺘﻔﺎﻭﺕ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ ﺭﻭﺗﺮ‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﺧﻂ ﺩﺳﺘﻮﺭ ﻭ ﻳﺎ ‪ CLI‬ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ ﺍﺯ ﻳﻚ ﺳﺎﺧﺘﺎﺭ ﺳﻠﺴﻠﻪ ﻣﺮﺍﺗﺒﻲ ﺗﺒﻌﻴﺖ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺳﺎﺧﺘﺎﺭ ﻓﻮﻕ ﻛﺎﺭﺑﺮﺍﻥ ﺭﺍ ﻣﻠﺰﻡ ﻣﻲ ﻧﻤﺎﻳﺪ ﻛﻪ ﺑﺮﺍﻱ ﺍﻧﺠﺎﻡ ﻫﺮ ﻧﻮﻉ ﻋﻤﻠﻴﺎﺕ ﺧﺎﺹ ﺑﻪ‬ ‫ﻳﻚ ‪ mode‬ﺑﺨﺼﻮﺹ ﻭﺍﺭﺩ ﺷﻮﻧﺪ‪ .‬ﻣﺜﻼ" ﺑﺮﺍﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﻭﺗﺮ‪ ،‬ﻛﺎﺭﺑﺮ‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ‪ mode‬ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻭ ﻳﺎ ‪interface‬‬

‫‪configuration‬‬

‫‪ mode‬ﻭﺍﺭﺩ ﺷﻮﺩ‪ .‬ﻫﺮ ‪ mode‬ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺍﺭﺍﻱ ﻳﻚ ‪ prompt‬ﻣﺨﺘﺺ ﺑﻪ ﺧﻮﺩ‬ ‫ﻣﻲ ﺑﺎﺷﺪ ﻛﻪ ﺍﺯ ﻃﺮﻳﻖ ﺁﻥ ﻣﻲ ﺗﻮﺍﻥ ﺩﺳﺘﻮﺭﺍﺕ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺗﺎﻳﭗ ﻭ ﺍﺯ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺗﻲ ﺁﻧﺎﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

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‫‪ ، IOS‬ﻳﻚ ﺳﺮﻭﻳﺲ ﻣﻔﺴﺮ ﺩﺳﺘﻮﺭ ﺑﺎ ﻧﺎﻡ ‪ EXEC‬ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﭘﺲ ﺍﺯ ﺩﺭﺝ ﻫﺮ ﺩﺳﺘﻮﺭ‪،‬‬

‫‪ EXEC‬ﺻﺤﺖ ﺁﻥ ﺭﺍ ﺑﺮﺭﺳﻲ ﻭ ﭘﺲ ﺍﺯ ﺗﺎﺋﻴﺪ ﺁﻥ ﺭﺍ ﺍﺟﺮﺍﺀ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ IOS‬ﺩﺭ‬

‫ﺟﻬﺖ ﺍﻓﺰﺍﻳﺶ ﺍﻣﻨﻴﺖ‪ ،‬ﺩﻭ ﺳﻄﺢ ﻣﺘﻔﺎﻭﺕ ﺩﺳﺘﻴﺎﺑﻲ ‪ user EXEC mode‬ﻭ‬ ‫‪ privileged EXEC mode‬ﺑﺎ ﻭﻳﮋﮔﻲ ﺯﻳﺮ ﺭﺍ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﻣﻔﺴﺮ ﺩﺳﺘﻮﺭ ) ‪( EXEC‬‬ ‫ﺩﺭ ﻧﻈﺮ ﻣﻲ ﮔﻴﺮﺩ‪:‬‬ ‫•‬

‫‪ : EXEC mode user‬ﺩﺭ ﺍﻳﻦ ‪ mode‬ﺻﺮﻓﺎ" ﻣﻲ ﺗﻮﺍﻥ ﺗﻌﺪﺍﺩ ﻣﺤﺪﻭﺩﻱ ﺍﺯ‬ ‫ﺩﺳﺘﻮﺭﺍﺕ ﻣﺎﻧﻴﺘﻮﺭﻳﻨﮓ ﺭﺍ ﺍﺟﺮﺍﺀ ﻧﻤﻮﺩ‪ .‬ﺑﻪ ﺍﻳﻦ ﻣﺪ ‪ view only‬ﻧﻴﺰ ﮔﻔﺘﻪ ﺷﺪﻩ ﻭ‬

‫ﻧﻤﻲ ﺗﻮﺍﻥ ﺩﺳﺘﻮﺭﺍﺗﻲ ﺭﺍ ﻛﻪ ﺑﺎﻋﺚ ﺗﻐﻴﻴﺮ ﺩﺭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺍﺟﺮﺍﺀ ﻧﻤﻮﺩ‪.‬‬ ‫•‬

‫‪ : privileged EXEC mode‬ﺩﺭ ﺍﻳﻦ ‪ mode‬ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﺗﻤﺎﻣﻲ‬ ‫ﺩﺳﺘﻮﺭﺍﺕ ﺭﻭﺗﺮ ﺩﺳﺘﻴﺎﺑﻲ ﺩﺍﺷﺖ ‪ .‬ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻦ ‪ mode‬ﻭ ﺩﺭ ﺟﻬﺖ ﺍﻓﺰﺍﻳﺶ‬ ‫ﺍﻣﻨﻴﺖ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺭﻭﺗﺮ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻧﻤﻮﺩ ﻛﻪ ﻛﺎﺭﺑﺮﺍﻥ ﺭﺍ ﻣﻠﺰﻡ ﺑﻪ ﺩﺭﺝ ﻧﺎﻡ ﻭ‬ ‫ﺭﻣﺰ ﻋﺒﻮﺭ ﺟﻬﺖ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺭﻭﺗﺮ ﻧﻤﺎﻳﺪ‪ Global configuration mode .‬ﻭ‬

‫ﺳﺎﻳﺮ ﺣﺎﻻﺕ ﻣﺘﻔﺎﻭﺕ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺻﺮﻓﺎ" ﺍﺯ ﻃﺮﻳﻖ ‪privileged EXEC mode‬‬ ‫ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪EXEC‬‬ ‫‪Mode‬‬ ‫‪ Router1> User‬ﺑﺮﺭﺳﻲ ﻭﺿﻌﻴﺖ ﺭﻭﺗﺮ‬ ‫ﻛﺎﺭﺑﺮﺩ‬

‫‪Prompt‬‬

‫‪Router1# privileged‬‬

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‫ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺣﺎﻻﺕ ﻣﺘﻔﺎﻭﺕ‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ‬

‫ﺷﻜﻞ ﺯﻳﺮ ﺣﺎﻻﺕ ﻣﺘﻔﺎﻭﺕ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

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‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﻛﻪ ﺩﺭ ﺷﻜﻞ ﻓﻮﻕ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ ،‬ﺟﻬﺖ ﻓﻠﺶ ﻗﺮﻣﺰ ﺭﻧﮓ ﺑﻪ ﺳﻤﺖ ‪Global‬‬ ‫‪ Configuration Mode‬ﻭ ‪ Privileged mode‬ﺍﺳﺖ ‪ .‬ﺍﻳﻦ ﺑﺪﺍﻥ ﻣﻌﻨﻲ ﺍﺳﺖ ﻛﻪ‬ ‫ﺟﻬﺖ ﻭﺭﻭﺩ ﺑﻪ ﺑﺮﺧﻲ ﺣﺎﻻﺕ ﺧﺎﺹ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻃﺮﻳﻖ ‪Global‬‬

‫‪ Configuration Mode‬ﺍﻗﺪﺍﻡ ﻧﻤﻮﺩ ﻭ ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﺩﻳﮕﺮ ﺍﻳﻦ ﻛﺎﺭ ﺍﺯ ﻃﺮﻳﻖ‬ ‫‪ Privileged mode‬ﺍﻧﺠﺎﻡ ﻣﻲ ﮔﺮﺩﺩ ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ‪ privileged EXEC mode‬ﺍﺯ ﻃﺮﻳﻖ ‪، user EXEC mode‬‬ ‫ﺍﺯ ﺩﺳﺘﻮﺭ ‪ enable‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ﺭﻭﺗﺮ ﺑﮕﻮﻧﻪ ﺍﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺪﻩ ﺍﺳﺖ‬

‫ﻛﻪ ﺟﻬﺖ ﻭﺭﻭﺩ ﺑﻪ ‪ privileged EXEC mode‬ﻛﺎﺭﺑﺮﺍﻥ ﺭﺍ ﻣﻠﺰﻡ ﺑﻪ ﺩﺭﺝ ﻧﺎﻡ ﻭ ﺭﻣﺰ‬ ‫ﻋﺒﻮﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﺭﻣﺰ ﻋﺒﻮﺭ ﺭﺍ ﻧﻴﺰ ﻭﺍﺭﺩ ﻧﻤﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺩﺭﺝ ﺻﺤﻴﺢ‬ ‫ﺭﻣﺰ ﻋﺒﻮﺭ‪ ،‬ﺑﻪ ‪ EXEC mode privileged‬ﻭﺍﺭﺩ ﺷﺪﻩ ﻭ ﺑﺎ ﺩﺭﺝ ﻳﻚ ﻋﻼﻣﺖ ﺳﻮﺍﻝ ﻣﻲ‬ ‫ﺗﻮﺍﻥ ﺩﺳﺘﻮﺭﺍﺕ ﻭ ﮔﺰﻳﻨﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ‪ mode‬ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻧﻤﻮﺩ ‪ .‬ﺷﻜﻞ ﺯﻳﺮ‬

‫ﻧﺤﻮﻩ ﺣﺮﻛﺖ ﺑﻴﻦ ‪ user EXEC mode‬ﻭ ‪privileged EXEC mode‬‬ ‫ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

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‫ﺭﺍ‬

‫ﻭﻳﮋﮔﻲ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪IOS‬‬ ‫ﺷﺮﻛﺖ ﺳﻴﺴﻜﻮ ﺗﺎﻛﻨﻮﻥ ﻧﺴﺨﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ IOS‬ﺭﺍ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻧﻤﻮﺩﻩ ﺍﺳﺖ ‪.‬‬

‫ﻫﺮ ‪ image‬ﺩﺍﺭﺍﻱ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺑﻪ ﺧﻮﺩ ﻣﻲ ﺑﺎﺷﺪ ‪.‬ﻋﻠﻴﺮﻏﻢ ﺗﻨﻮﻉ ﺑﺴﻴﺎﺭ ﮔﺴـــﺘﺮﺩﻩ‬

‫‪ IOS images‬ﺑﺮﺍﻱ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺳﻴﺴﻜﻮ ‪ ،‬ﺳﺎﺧﺘﺎﺭ ﺍﻭﻟﻴﻪ ﺩﺳﺘﻮﺭﺍﺕ ﭘﻴﻜﺮﺑﻨــﺪﻱ ﺩﺭ ﺁﻧﺎﻥ‬ ‫ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﺪ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﻛﺴﺐ ﻣﻬﺎﺭﺕ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﻜﺮﺑﻨــﺪﻱ ﻭ ﺍﺷﻜﺎﻝ ﺯﺩﺍﺋﻲ ﻳﻚ‬ ‫ﺩﺳﺘﮕﺎﻩ ﺧﺎﺹ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺗﺠﺎﺭﺏ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻩ ﻫﺎ ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬ ‫ﺍﺳﺎﻣﻲ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﻫﺮ ﻳﻚ ﺍﺯ ﻧﺴﺨﻪ ﻫﺎﻱ ‪ IOS‬ﺍﺯ ﺳﻪ ﺑﺨﺶ ﻋﻤﺪﻩ ﺗﺸـﻜﻴﻞ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻣﺤﻴﻄﻲ ﻛﻪ ‪ image‬ﺑﺮ ﺭﻭﻱ ﺁﻥ ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﺩ‬

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‫ﻭﻳﮋﮔﻲ ﻣﻨﺤﺼﺮﺑﻔﺮﺩ ‪image‬‬

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‫ﻣﺤﻞ ﺍﺟﺮﺍﺀ ‪ image‬ﻭ ﻭﺿﻌﻴﺖ ﻓﺸﺮﺩﻩ ﺑﻮﺩﻥ ﺁﻥ‬

‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ Advisor Cisco Software‬ﻣﻲ ﺗﻮﺍﻥ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﺧﺎﺻﻲ ﺍﺯ ‪ IOS‬ﺭﺍ‬ ‫ﺍﻧﺘﺨﺎﺏ ﻧﻤﻮﺩ‪ .‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻓﻮﻕ ﻳﻚ ﺍﺑﺰﺍﺭ ﻣﺤﺎﻭﺭﻩ ﺍﻱ ﺍﺳﺖ ﻛﻪ ﭘﺲ ﺍﺯ ﻧﻤﺎﻳﺶ ﻭﺿﻌﻴﺖ‬ ‫ﻣﻮﺟﻮﺩ‪ ،‬ﺍﻣﻜﺎﻥ ﺍﻧﺘﺨﺎﺏ ﮔﺰﻳﻨﻪ ﻫﺎﺋﻲ ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﻭﺍﻗﻌﻴﺖ ﻫﺎﻱ ﺷﺒﻜﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﻳﻜﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻣﻮﺍﺭﺩﻱ ﻛﻪ ﺩﺭ ﺯﻣﺎﻥ ﺍﻧﺘﺨﺎﺏ ﻳﻚ ‪ IOS image‬ﺟﺪﻳﺪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺁﻥ‬ ‫ﺗﻮﺟﻪ ﮔﺮﺩﺩ‪ ،‬ﺳﺎﺯﮔﺎﺭﻱ ﺁﻥ ﺑﺎ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﻭ ‪ RAM‬ﺍﺳﺖ‪ .‬ﻧﺴﺨﻪ ﻫﺎﻱ ﺟﺪﻳﺪﺗﺮ ﻋﻤﻮﻣﺎ"‬

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‫ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬. ‫ﺩﺍﺭﺍﻱ ﺍﻣﻜﺎﻧﺎﺕ ﺑﻴﺸﺘﺮﻱ ﺑﻮﺩﻩ ﻭ ﺑﻪ ﺣﺎﻓﻈﻪ ﺑﻴﺸﺘﺮﻱ ﻧﻴﺰ ﻧﻴﺎﺯ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‬

‫ ﻣﻮﺟﻮﺩ ﻭ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺭﺍ ﻣﺸﺎﻫﺪﻩ‬image ‫ ﻣﻲ ﺗﻮﺍﻥ ﻭﺿﻌﻴﺖ‬Show version ‫ﺩﺳﺘﻮﺭ‬

‫ ﻣﻲ ﺑﺎﻳﺴﺖ ﻭﺿﻌﻴﺖ ﺣﺎﻓﻈﻪ ﺁﻥ‬، IOS ‫ ﻗﺒﻞ ﺍﺯ ﻧﺼﺐ ﻳﻚ ﻧﺴﺨﻪ ﺟﺪﻳﺪ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬. ‫ﻧﻤﻮﺩ‬ .‫ ﺑﺮﺭﺳﻲ ﮔﺮﺩﺩ‬، ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻃﻤﻴﻨﺎﻥ ﺍﺯ ﻭﺟﻮﺩ ﻇﺮﻓﻴﺖ ﻛﺎﻓﻲ‬ :‫ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‬Show version ‫ ﺍﺯ ﺩﺳﺘﻮﺭ‬، RAM ‫ﺑﺮﺍﻱ ﻣﺸﺎﻫﺪﻩ ﻣﻴﺰﺍﻥ ﺣﺎﻓﻈﻪ‬ ‫ﺧﺮﻭﺟﻲ‬

‫ﺩﺳﺘﻮﺭ ﺗﺎﻳﭗ‬

....... System image file is "flash:c2600-dos-mz_1204_T.bin" Processor board ID JAB040202ZW (201830944) M860 processor: part number 0, mask 49 Bridging software. X.25 software, Version Router>Show 3.0.0. Version 2 FastEthernet/IEEE 802.3 interface(s) 32K bytes of non-volatile configuration memory. 8192K bytes of processor board System flash (Read/Write) Configuration register is 0x2102

322

.‫ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‬Show flash ‫ﺑﺮﺍﻱ ﻣﺸﺎﻫﺪﻩ ﻣﻴﺰﺍﻥ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺩﺳﺘﻮﺭ‬ ‫ﺧﺮﻭﺟﻲ‬

‫ﺩﺳﺘﻮﺭ ﺗﺎﻳﭗ‬

System flash directory: File Length Name/status 1 6399468 c2600-dosmz_120-4_T.bin [6399532 bytes used, 1989076 available, 8388608 total] 8192K bytes of processor board System flash (Read/Write)

323

Router>show flash

‫ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ‪ :‬ﺍﻳﺠﺎﺩ ﻳﻚ ‪Hyper Terminal Session‬‬ ‫ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ ﺩﺍﺭﺍﻱ ﻳﻚ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺳﺮﻳﺎﻝ ﻏﻴﺮﻫﻤﺰﻣﺎﻥ ‪TIA/EIA-‬‬ ‫‪ 232‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﻳﻚ ﺗﺮﻣﻴﻨﺎﻝ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ‪ ،‬ﺍﺯ ﻛﺎﺑﻞ ﻫﺎ ﻭ ﺁﺩﺍﭘﺘﻮﺭﻫﺎﻱ‬ ‫ﺧﺎﺻﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ :‬ﺗﺮﻣﻴﻨﺎﻝ‪ ،‬ﻳﻚ ﺗﺮﻣﻴﻨﺎﻝ ﺍﺳﻜﻲ ﻭ ﻳﺎ ﻛﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ ﻛﻪ ﺑﺮ ﺭﻭﻱ ﺁﻥ‬

‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺷﺒﻴﻪ ﺳﺎﺯ ﺗﺮﻣﻴﻨﺎﻝ ﻧﻈﻴﺮ ‪ HyperTerminal‬ﺍﺟﺮﺍﺀ ﺷﺪﻩ ﺑﺎﺷﺪ‪ .‬ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ‬ ‫ﻛﺎﻣﭙﻮﺗﺮ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ﺍﺯ ‪ RJ-45 to RJ-45 rollover cable‬ﺑﻪ ﻫﻤﺮﺍﻩ‬ ‫ﺁﺩﺍﭘﺘﻮﺭ ‪ RJ-45 to DB-9‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺷﺒﻴﻪ ﺳﺎﺯ ﺗﺮﻣﻴﻨﺎﻝ‬

‫ﻫﺮ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺍﺯ ﻳﻚ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ﻧﻮﻉ ﺑﺮﻧﺎﻣﻪ ﺷﺒﻴﻪ ﺳﺎﺯ ﺗﺮﻣﻴﻨﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫‪ ، HyperTerminal‬ﻳﻚ ﺑﺮﻧﺎﻣﻪ ﺳﺎﺩﻩ ﺷﺒﻴﻪ ﺳﺎﺯ ﺗﺮﻣﻴﻨﺎﻝ ﺍﺳﺖ ﻛﻪ ﺍﺯ ﺁﻥ ﺩﺭ ﻧﺴﺨﻪ ﻫﺎﻱ‬ ‫ﻣﺨﺘﻠﻒ ﻭﻳﻨﺪﻭﺯ ﺍﺳﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﻭﺍﻗﻊ‪ ،‬ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻫﻤﺮﺍﻩ ‪ ، HyperTerminal‬ﻧﻈﻴﺮ‬

‫ﻳﻚ ﺗﺮﻣﻴﻨﺎﻝ ﺭﻓﺘﺎﺭ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺻﻔﺤﻪ ﻛﻠﻴﺪ ﻓﺮﺍﻣﻴﻦ ﺗﺎﻳﭗ ﻭ ﭘﺲ ﺍﺯ ﺍﺭﺳﺎﻝ ﺑﻪ‬

‫ﺭﻭﺗﺮ‪ ،‬ﻧﺘﺎﻳﺞ ﺍﺯ ﻃﺮﻳﻖ ﻧﻤﺎﻳﺸﮕﺮ ﻛﺎﻣﭙﻴﻮﺗﺮ‪ ،‬ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ(‪.‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﻛﺎﺑﻞ ‪ rollover‬ﻭ ﺑﺮﻧﺎﻣﻪ ﺍﻱ ﻧﻈﻴﺮ ‪ ، HyperTerminal‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ‬

‫ﺭﻭﺵ ﺍﺗﺼﺎﻝ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺑﺮﺭﺳﻲ ﻭ ﺗﻐﻴﻴﺮ ﭘﺎﺭﺍﻣﺘﺮﻫﺎﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ‬ ‫ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺗﺠﻬﻴﺰﺍﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬

‫ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ ﺑﻪ ﺗﺠﻬﻴﺰﺍﺕ ﻭ ﺍﻣﻜﺎﻧﺎﺕ ﺯﻳﺮ ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ ‪:‬‬

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‫ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻛﻪ ﺩﺍﺭﺍﻱ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺳﺮﻳﺎﻝ ﺍﺳﺖ ﻭ ﺑﺮﻧﺎﻣﻪ‬ ‫‪ HyperTerminal‬ﺑﺮ ﺭﻭﻱ ﻧﺼﺐ ﺷﺪﻩ ﺑﺎﺷﺪ ‪.‬‬

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‫ﻳﻚ ﺭﻭﺗﺮ‬

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‫ﻛﺎﺑﻞ ﻛﻨﺴﻮﻝ ﻭ ﻳﺎ ‪ rollover‬ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ‬

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‫ﺍﻳﺠﺎﺩ ﻳﻚ ‪HyperTerminal Session‬‬

‫ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻳﻚ ‪ HyperTerminal Session‬ﻭ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ ﻣﺮﺍﺣﻞ ﺯﻳﺮ‬

‫ﺭﺍ ﺩﻧﺒﺎﻝ ﻣﻲ ﻧﻤﺎﺋﻴﻢ ‪:‬‬ ‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ ‪ -‬ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ ‪ :‬ﺩﺭ ﺍﻭﻟﻴﻦ ﺍﻗﺪﺍﻡ ﻣﻲ ﺑﺎﻳﺴﺖ ﻛﺎﺑﻞ ‪ rollover‬ﺭﺍ ﺑﻪ‬ ‫ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ﻭ ﺳﺮ ﺩﻳﮕﺮ ﺁﻥ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺁﺩﺍﭘﺘﻮﺭ ‪ DB-9‬ﻭ ﻳﺎ ‪ DB-25‬ﺑﻪ‬ ‫ﭘﻮﺭﺕ ﺳﺮﻳﺎﻝ ) ‪ ( COM‬ﻛﺎﻣﭙﻴﻮﺗﺮ ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪.‬‬

‫ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮ ﺑﻪ ﻛﺎﻣﭙﻴﻮﺗﺮ )ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ(‬ ‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ ‪ -‬ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ‪ : HyperTerminal‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﭘﺲ ﺍﺯ ﺭﻭﺷﻦ‬ ‫ﻛﺮﺩﻥ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﺭﻭﺗﺮ ‪ ،‬ﺑﺮﻧﺎﻣﻪ ‪ HyperTerminal‬ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﺴﻴﺮ ﺯﻳﺮ ﺭﺍ ﺍﺟﺮﺍﺀ‬ ‫ﻣﻲ ﻧﻤﺎﺋﻴﻢ ‪.‬‬ ‫‪Start > Programs > Accessories‬‬ ‫‪> Communications > Hyper‬‬ ‫‪Terminal‬‬ ‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ ‪ -‬ﺍﻧﺘﺨﺎﺏ ﻳﻚ ﻧﺎﻡ ﺑﺮﺍﻱ ‪ : HyperTerminal Session‬ﺩﺭ ﺍﻳﻦ‬

‫ﻣﺮﺣﻠﻪ ﺑﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﻣﻮﺭﺩ ﻧﻈﺮ ‪ ،‬ﻳﻚ ﻧﺎﻡ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪.‬‬ ‫‪325‬‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪-‬ﺍﻧﺘﺨﺎﺏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺍﺭﺗﺒﺎﻃﻲ ﻛﺎﻣﭙﻴﻮﺗﺮ ‪ :‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫ﺍﺭﺗﺒﺎﻃﻲ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﺎ ﺭﻭﺗﺮ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﺋﻴﻢ ) ﭘﻮﺭﺕ ﺳﺮﻳﺎﻝ ‪.( COM1 :‬‬

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‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪ -‬ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺧﺼﺎﻳﺺ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺍﺭﺗﺒﺎﻃﻲ ‪ :‬ﺩﺭ ﺍﻳﻦ ﻣﺮﺣﻠﻪ ﺧﺼﺎﻳﺺ‬ ‫ﭘﻮﺭﺕ ﺳﺮﻳﺎﻝ ﺍﻧﺘﺨﺎﺏ ﺷﺪﻩ ﺩﺭ ﻣﺮﺣﻠﻪ ﻗﺒﻞ ) ‪ ( COM1‬ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﺋﻴﻢ ‪.‬‬ ‫‪Bits per second: 9600‬‬ ‫‪• Data bits: 8‬‬ ‫‪• Parity: None‬‬ ‫‪• Stop bits: 1‬‬ ‫‪• Flow control: None‬‬ ‫•‬

‫ﭘﺲ ﺍﺯ ﻓﻌﺎﻝ ﺷﺪﻥ ﭘﻨﺠﺮﻩ ‪ ، HyperTerminal session‬ﺭﻭﺗﺮ ﺭﺍ ﺭﻭﺷﻦ ﻧﻤﻮﺩﻩ ﻭ ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﻛﻪ ﺭﻭﺗﺮ ﺭﻭﺷﻦ ﺍﺳﺖ ‪ ،‬ﻛﻠﻴﺪ ‪ Enter‬ﺭﺍ ﻓﻌﺎﻝ ﻭ ﺩﺭ ﺍﻧﺘﻈﺎﺭ ﭘﺎﺳﺦ ﺭﻭﺗﺮ ﻣﻲ ﻣﺎﻧﻴﻢ ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺕ ﭘﺎﺳﺦ ﺭﻭﺗﺮ ‪ ،‬ﻳﻚ ﺍﺭﺗﺒﺎﻁ ﻣﻮﻓﻘﻴﺖ ﺁْﻣﻴﺰ ﺑﺎ ﺭﻭﺗﺮ ﺑﺮﻗﺮﺍﺭ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﻣﺮﺣﻠﻪ ﺷﺸﻢ ‪ :‬ﺑﺴﺘﻦ ‪ : Session‬ﺑﺮﺍﻱ ﺧﺎﺗﻤﻪ ﺩﺍﺩﻥ ﺑﻪ ‪ ، Console session‬ﮔﺰﻳﻨﻪ‬ ‫‪ Exit‬ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻣﻨﻮﻱ ‪ Exit‬ﺍﻧﺘﺨﺎﺏ ﻧﻤﻮﺩﻩ ﻭ ﺁﻥ ﺭﺍ ﺑﺎ ﻳﻚ ﻧﺎﻡ ﺩﻟﺨﻮﺍﻩ ﺫﺧﻴﺮﻩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‬ ‫) ﺍﺳﺘﻔﺎﺩﻩ ﻣﺠﺪﺩ ﺍﺯ ﺁﻥ ﺩﺭ ﺁﻳﻨﺪﻩ (‪.‬‬

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‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﻲ ﺭﻭﺗﺮ‬ ‫ﺭﻭﺗﺮ ﻳﻜﻲ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺷﺒﻜﻪ ﺍﻱ ﻣﻬﻢ ﻭ ﺣﻴﺎﺗﻲ ﺍﺳﺖ ﻛﻪ ﺍﺯ ﺁﻥ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ‬ ‫‪ LAN‬ﻭ ‪ WAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮﻫﺎ ﺗﺎﻛﻨﻮﻥ ﺩﺭ ﻣﺪﻝ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﻭ ﺑﺎ ﻣﻌﻤﺎﺭﻱ‬ ‫ﻣﺨﺘﻠﻒ ﻃﺮﺍﺣﻲ‪ ،‬ﺗﻮﻟﻴﺪ ﻭ ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﻄﻠﺐ ﺑﺎ ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﺩﺍﺧﻠﻲ ﻳﻚ ﺭﻭﺗﺮ‬ ‫ﺁﺷﻨﺎ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬

‫ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﻲ ﺭﻭﺗﺮ‬ ‫•‬

‫ﭘﺮﺩﺍﺯﻧﺪﻩ ) ‪ : ( CPU‬ﭘﺮﺩﺍﺯﻧﺪﻩ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺟﺮﺍﻱ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﺩﺭ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ‬ ‫ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ ‪ .‬ﻣﻘﺪﺍﺭﺩﻫﻲ ﺍﻭﻟﻴﻪ ﺳﻴﺴﺘﻢ‪ ،‬ﻋﻤﻠﻴﺎﺕ ﺭﻭﺗﻴﻨﮓ ﻭ ﻛﻨﺘﺮﻝ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺷﺒﻜﻪ‬ ‫ﺍﺯ ﺟﻤﻠﻪ ﻭﻇﺎﻳﻒ ﻳﻚ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻣﻲ ﺑﺎﺷﺪ‪ ،CPU .‬ﻳﻚ ﺭﻳﺰﭘﺮﺩﺍﺯﻧﺪﻩ ﺍﺳﺖ ﻭ ﺩﺭ‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮒ ﻣﻤﻜﻦ ﺍﺳﺖ ﺍﺯ ﭼﻨﺪﻳﻦ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺣﺎﻓﻈﻪ ﺍﺻﻠﻲ ) ‪ : ( RAM‬ﺍﺯ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺍﻃﻼﻋﺎﺕ ﺟﺪﻭﻝ‬

‫ﺭﻭﺗﻴﻨﮓ ‪ ،‬ﺻﻒ ﻫﺎﻱ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‪ ،‬ﺍﺟﺮﺍﺀ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻭ ‪ cache‬ﺳﻮﺋﻴﭽﻴﻨﮓ‬

‫ﺳﺮﻳﻊ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻛﺜﺮ ﺭﻭﺗﺮﻫﺎ ‪ ،‬ﺣﺎﻓﻈﻪ ‪ RAM‬ﻓﻀﺎﻱ ﺯﻣﺎﻥ ﺍﺟﺮﺍﺀ ﺑﺮﺍﻱ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭ ‪ IOS‬ﻭ ﺯﻳﺮ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺣﺎﻓﻈﻪ ‪ RAM‬ﻣﻨﻄﻘﺎ" ﺑﻪ‬

‫ﺩﻭ ﺑﺨﺶ ﺣﺎﻓﻈﻪ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺍﺻﻠﻲ ﻭ ﺣﺎﻓﻈﻪ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ ﻣﺸـــﺘﺮﻙ ﺗﻘﺴـــﻴﻢ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯﺣﺎﻓﻈﻪ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ ﻣﺸﺘﺮﻙ )‪ (Shared I/O‬ﺗﻮﺳﻂ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﻣﻮﻗﺖ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺎ‬

‫ﺗﻮﺟﻪ ﺑﻪ ﺗﻜﻨﻮﻟﻮﮊﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺳﺎﺧﺖ ﺍﻳﻨﮕﻮﻧﻪ ﺣﺎﻓﻈﻪ ﻫﺎ‪ ،‬ﭘﺲ ﺍﺯ ﺧﺎﻣﻮﺵ‬

‫ﻛﺮﺩﻥ ﻭ ﻳﺎ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻣﺠﺪﺩ ﺭﻭﺗﺮ ﺍﻃﻼﻋــــﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ RAM‬ﺣﺬﻑ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺣﺎﻓﻈﻪ ﻫﺎﻱ ﻓﻮﻕ ﻣﻌﻤﻮﻻ" ﺍﺯ ﻧﻮﻉ ‪ ) DRAM‬ﺣﺎﻓﻈﻪ ‪ RAM‬ﭘﻮﻳﺎ ( ﺑﻮﺩﻩ ﻭ‬ ‫ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﻓﺰﻭﺩﻥ ﻣﺎﮊﻭﻝ ﻫﺎﻱ ‪ DIMMs‬ﻇﺮﻓﻴﺖ ﺁﻧﺎﻥ ﺭﺍ ﺗﻐﻴﻴﺮ ﻭ ﺍﻓﺰﺍﻳﺶ ﺩﺍﺩ‪.‬‬

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‫ﺣﺎﻓﻈﻪ ﻓﻠﺶ ) ‪ : ( Flash‬ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﺣﺎﻓﻈﻪ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﻧﺴﺨﻪ ﻛﺎﻣﻞ ﻧﺮﻡ‬

‫ﺍﻓﺰﺍﺭ ‪ IOS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮ‪ ،‬ﻣﻌﻤﻮﻻ" ‪ IOS‬ﭘﻴﺶ ﻓﺮﺽ ﺧﻮﺩ ﺭﺍ ﺍﺯ ﺣﺎﻓﻈﻪ‬

‫ﻓﻠﺶ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﻜﻨﻮﻟﻮﮊﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺳﺎﺧﺖ ﺍﻳﻨﮕﻮﻧﻪ‬ ‫ﺣﺎﻓﻈﻪ ﻫﺎ‪ ،‬ﻫﻤﻮﺍﺭﻩ ﻣﻲ ﺗﻮﺍﻥ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺩﺭﻭﻥ ﺁﻧﺎﻥ ﺭﺍ ﺍﺭﺗﻘﺎﺀ ﻭ ﺑﺎ ﻳﻚ‬

‫ﻧﺴﺨﻪ ﺟﺪﻳﺪ ﺟﺎﻳﮕﺰﻳﻦ ﻧﻤﻮﺩ‪ IOS .‬ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﻪ ﺻﻮﺭﺕ ﻓﺸﺮﺩﻩ ﻭ ﻳﺎ ﻣﻌﻤﻮﻟﻲ‬ ‫ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺑﺎﺷﺪ ‪ .‬ﺩﺭ ﺍﻛﺜﺮ ﺭﻭﺗﺮﻫﺎ ﻳﻚ ﻧﺴﺨﻪ ﺍﺟﺮﺍﺋﻲ ﺍﺯ ‪ IOS‬ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ‬

‫ﺭﻭﺗﺮ ﺑﻪ ﺣﺎﻓﻈﻪ ‪ RAM‬ﺍﻧﺘﻘﺎﻝ ﻣﻲ ﻳﺎﺑﺪ‪ .‬ﺩﺭ ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎ‪ IOS ،‬ﻣﻤﻜﻦ ﺍﺳﺖ‬ ‫ﻣﺴﺘﻘﻴﻤﺎ" ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺍﺟﺮﺍﺀ ﮔﺮﺩﺩ‪ .‬ﺑﺎ ﺍﻓﺰﻭﺩﻥ ﻭ ﻳﺎ ﺗﻌﻮﻳﺾ ﻣﺎﮊﻭﻝ ﻫﺎﻱ‬ ‫‪ SIMMs‬ﻭ ﻳﺎ ﻛﺎﺭﺕ ﻫﺎﻱ ‪ PCMCIA‬ﻣﻲ ﺗﻮﺍﻥ ﻇﺮﻓﻴﺖ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺭﺍ ﺍﺭﺗﻘﺎﺀ ﺩﺍﺩ‪.‬‬ ‫•‬

‫ﺣﺎﻓﻈﻪ ‪ : NVRAM‬ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﺣﺎﻓﻈﻪ ﻫﺎﻱ ﻏﻴﺮ ﻓﺮﺍﺭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﭘﻴﻜﺮﺑﻨﺪﻱ‬

‫ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﺩﺳﺘﮕﺎﻩ ﻫﺎ‪ NVRAM ،‬ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﺗﻜﻨﻮﻟﻮﮊﻱ ‪ EEPROMs‬ﻭ ﺩﺭ ﺳﺎﻳﺮ ﺩﺳﺘﮕﺎﻩ ﻫﺎ ﺑﻪ ﺻﻮﺭﺕ ﺣﺎﻓﻈﻪ ﻫﺎﻱ ﻓﻠﺶ ﭘﻴﺎﺩﻩ‬

‫ﺳﺎﺯﻱ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ‪ NVRAM‬ﭘﺲ ﺍﺯ ﺧﺎﻣﻮﺵ ﺷﺪﻥ ﻭ ﻳﺎ ﺭﺍﻩ‬ ‫ﺍﻧﺪﺍﺯﻱ ﻣﺠﺪﺩ ﺭﻭﺗﺮ ﺍﺯ ﺑﻴﻦ ﻧﺨﻮﺍﻫﻨﺪ ﺭﻓﺖ‪.‬‬ ‫•‬

‫ﮔﺬﺭﮔﺎﻩ ﻫﺎ ) ‪ : ( Buses‬ﺍﻛﺜﺮ ﺭﻭﺗﺮﻫﺎ ﺷﺎﻣﻞ ﻳﻚ ﮔﺬﺭﮔﺎﻩ ﺳﻴﺴﺘﻢ ﻭ ﻳﻚ ﮔﺬﺭﮔﺎﻩ‬ ‫ﭘﺮﺩﺍﺯﻧﺪﻩ ﻣﻲﺑﺎﺷﻨﺪ ‪ .‬ﺍﺯ ﮔﺬﺭﮔﺎﻩ ﺳﻴﺴﺘﻢ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻭ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻭ ﻳﺎ ﺗﺠﻬﻴﺰﺍﺕ ﺟﺎﻧﺒﻲ ﻧﺼﺐ ﺷﺪﻩ ﺩﺭ ﻳﻜﻲ ﺍﺯ ﺍﺳﻼﺕ ﻫﺎﻱ ﺳﻴﺴﺘﻢ‪،‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﮔﺬﺭﮔﺎﻩ ﻓﻮﻕ ﻣﺴﺌﻮﻟﻴﺖ ﻣﺒﺎﺩﻟﻪ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ‬

‫ﻫﺎ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ ) ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ (‪.‬‬

‫ﮔﺬﺭﮔﺎﻩ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺗﻮﺳﻂ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﻋﻨﺎﺻﺮ ﺍﺯ ﻃﺮﻳﻖ ﺣﺎﻓﻈﻪ‬ ‫ﺍﺻﻠﻲ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﮔﺬﺭﮔﺎﻩ ﻣﺴﺌﻮﻟﻴﺖ ﻣﺒﺎﺩﻟﻪ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎ ﻭ ﺩﺍﺩﻩ‬ ‫ﺑﻪ ﻳﻚ ﺁﺩﺭﺱ ﺧﺎﺹ ﺍﺯ ﺣﺎﻓﻈﻪ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ ) ﺫﺧﻴﺮﻩ ﻭ ﺑﺎﺯﻳﺎﺑﻲ (‪.‬‬

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‫ﺣﺎﻓﻈﻪ ‪ : ROM‬ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﺣﺎﻓﻈﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺩﺍﺋﻢ ﻛﺪ ﺍﺷﻜﺎﻝ ﺯﺩﺍﺋﻲ ﺭﺍﻩ ﺍﻧﺪﺍﺯ‬

‫) ‪ ( ROM Monitor‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲﮔﺮﺩﺩ ‪ .‬ﻣﻬﻤﺘﺮﻳﻦ ﻭﻇﻴﻔﻪ ﺣﺎﻓﻈﻪ ‪ ، ROM‬ﺗﺴﺖ ﻭ‬ ‫ﻋﻴﺐ ﻳﺎﺑﻲ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﻭ ﺍﺳﺘﻘﺮﺍﺭ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪ IOS‬ﺍﺯ‬

‫ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺑﻪ ﺩﺭﻭﻥ ﺣﺎﻓﻈﻪ ‪ RAM‬ﻣﻲﺑﺎﺷﺪ‪ .‬ﺑﺮﺧﻲ ﺭﻭﺗﺮﻫﺎ ﺩﺍﺭﺍﻱ ﻳﻚ ﻧﺴﺨﻪ‬ ‫ﺧﺎﺹ ﻭ ﺳﺒﻚ ﺗﺮ ﺍﺯ ‪ IOS‬ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺁﻥ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﮔﺰﻳﻨﻪ ﻭ‬

‫ﻣﻨﺒﻊ ﺟﺎﻳﮕﺰﻳﻦ ﺩﺭ ﺯﻣﺎﻥ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ‬

‫ﺍﻳﻨﮕﻮﻧﻪ ﺣﺎﻓﻈﻪ ﻫﺎ ﺭﺍ ﻧﻤﻲ ﺗﻮﺍﻥ ﺣﺬﻑ ﻧﻤﻮﺩ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﻧﻴﺎﺯ ﺑﻪ ﺍﺭﺗﻘﺎﺀ ‪ ،‬ﻣﻲﺑﺎﻳﺴﺖ‬

‫ﺗﺮﺍﺷﻪ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺗﻌﻮﻳﺾ ﻧﻤﻮﺩ ‪.‬‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ‪ :‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺗﺼﺎﻻﺕ ﺭﻭﺗﺮ ﺑﻪ ﺩﻧﻴﺎﻱ ﺧﺎﺭﺝ ﺭﺍ ﺑﺮﻋﻬﺪﻩ‬ ‫ﺩﺍﺷﺘﻪ ﻭ‬

‫ﻣﻲ ﺗﻮﺍﻥ ﺁﻧﺎﻥ ﺭﺍ ﺑﻪ ﺳﻪ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩ‪:‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ‪ :‬ﺍﻳﻦ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﻌﻤﻮﻻ" ﻳﻜﻲ ﺍﺯ ﮔﺰﻳﻨﻪ‬ ‫ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺍﺗﺮﻧﺖ ﻭ ﻳﺎ ‪ Token Ring‬ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ‬

‫ﺗﺮﺍﺷﻪ ﻫﺎﻱ ﻛﻨﺘﺮﻟﻲ ﺧﺎﺻﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﻣﻨﻄﻖ ﻻﺯﻡ ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﺳﻴﺴﺘﻢ ﺑﻪ ﻣﺤﻴﻂ‬ ‫ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﻪ ﺻﻮﺭﺕ‬

‫ﺛﺎﺑﺖ ﻭ ﻳﺎ ﻣﺎﮊﻭﻻﺭ ) ﭘﻴﻤﺎﻧﻪ ﺍﻱ ﻭ ﻗﺎﺑﻞ ﺍﻓﺰﺍﻳﺶ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻴﺎﺯ( ﺑﺎﺷﺪ‪.‬‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺷﺒﻜﻪ ‪ : WAN‬ﺷﺎﻣﻞ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺳﺮﻳﺎﻝ‪ ISDN ،‬ﻭ‬ ‫‪ ) CSUs‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ ( Channel Service Unit‬ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﻫﻤﺎﻧﻨﺪ ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫ﺷﺒــﻜﻪ ﻫﺎﻱ ﻣﺤﻠﻲ‪ ،‬ﺍﻳﻦ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻧﻴﺰ ﺩﺍﺭﺍﻱ ﺗﺮﺍﺷــــﻪ ﻫﺎﻱ ﻛﻨﺘﺮﻟﻲ ﺧﺎﺻﻲ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﻣﻨﻄﻖ ﻻﺯﻡ ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﺳﻴﺴﺘﻢ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﻪ ﺻﻮﺭﺕ ﺛﺎﺑﺖ ﻭ ﻳﺎ ﻣﺎﮊﻭﻻﺭ ﺑﺎﺷﺪ‪.‬‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻛﻨﺴﻮﻝ ﻭ ﻛﻤﻜﻲ ‪ :‬ﺍﻳﻦ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ‪ ،‬ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﺮﻳﺎﻟﻲ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺍﺯ ﺁﻧﺎﻥ ﺟﻬﺖ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﻮﺭﺕ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺭﺍ ﻧﻤﻲ ﺗﻮﺍﻥ ﺑﻪ ﻋﻨﻮﺍﻥ ﭘﻮﺭﺕ ﻫﺎﻱ ﺷﺒﻜﻪ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺖ ﻭ ﺍﺯ ﺁﻧﺎﻥ ﺻﺮﻓﺎ" ﺟﻬﺖ‬

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‫ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺍﺯ ﻃﺮﻳﻖ ﭘﻮﺭﺕ ﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﻣﻮﺩﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺑﻌﻤﻞ‬

‫ﻣﻲ ﺁﻳﺪ‪.‬‬ ‫•‬

‫ﻣﻨﺒﻊ ﺗﻐﺬﻳﻪ ‪ :‬ﻣﻨﺒﻊ ﺗﻐﺬﻳﻪ ﺗﻮﺍﻥ ﻻﺯﻡ ﺑﺮﺍﻱ ﻋﻤﻠﻜﺮﺩ ﺻﺤﻴﺢ ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﻲ ﺭﻭﺗﺮ ﺭﺍ‬ ‫ﺗﺎﻣﻴﻦ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮒ ﻣﻤﻜﻦ ﺍﺳﺖ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ﻣﻨﺒﻊ ﺗﻐﺬﻳﻪ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﻛﻮﭼﻚ ﻣﻨﺒﻊ ﺗﻐﺬﻳﻪ ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﻪ ﺻﻮﺭﺕ ‪ External‬ﺑﺎﺷﺪ‪.‬‬ ‫ﻣﺤﻞ ﻧﺼﺐ ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﻲ ﺩﺭﻭﻥ ﺭﻭﺗﺮ‬

‫ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﻻﺯﻡ ﻧﻴﺴﺖ ﻛﻪ ﺑﺎ ﻣﺤﻞ ﻧﺼﺐ ﻋﻨﺎﺻﺮ ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﺩﺭﻭﻥ ﺭﻭﺗﺮ ﺁﺷﻨﺎ‬

‫ﺑﺎﺷﻴﻢ ﻭﻟﻲ ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﻧﻈﻴﺮ ﺍﺭﺗﻘﺎﺀ ﺣﺎﻓﻈﻪ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﻣﻲ ﺗﻮﺍﻧﺪ ﺿﺮﻭﺭﺕ ﺧﺎﺹ ﺧﻮﺩ‬ ‫ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ‪.‬‬

‫ﻧﻮﻉ ﻋﻨﺎﺻﺮ ﻭ ﻣﺤﻞ ﻧﺼﺐ ﺁﻧﺎﻥ ﺩﺭ ﺭﻭﺗﺮﻫﺎ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺪﻝ ﺁﻧﺎﻥ ﻣﻲ ﺗﻮﺍﻧﺪ ﻣﺘﻔﺎﻭﺕ ﻭ ﻣﺘﻐﻴﺮ‬ ‫ﺑﺎﺷﺪ ‪ .‬ﺷﻜﻞ ﺯﻳﺮ ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﺩﺍﺧﻠﻲ ﺩﺭ ﻳﻚ ﺭﻭﺗﺮ ‪ ٢٦٠٠‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﺩﺍﺧﻠﻲ ﺭﻭﺗﺮ ‪ ) ٢٦٠٠‬ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ (‬

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‫ﺷﻜﻞ ﺯﻳﺮ ﺑﺮﺧﻲ ﻛﺎﻧﻜﺘﻮﺭﻫﺎﻱ ﺧﺎﺭﺟﻲ ﻳﻚ ﺭﻭﺗﺮ ‪ ٢٦٠٠‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﻛﺎﻧﻜﺘﻮﺭﻫﺎﻱ ﺧﺎﺭﺟﻲ ﺭﻭﺗﺮ ‪ ) ٢٦٠٠‬ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ (‬

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‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺭﻭﺗﺮ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺗﺼﺎﻻﺕ ﺭﻭﺗﺮ ﺑﻪ ﺩﻧﻴﺎﻱ ﺧﺎﺭﺝ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﻭ ﻣﻲ ﺗﻮﺍﻥ‬ ‫ﺁﻧﺎﻥ ﺭﺍ ﺑﻪ ﺳﻪ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺷﺒﻜﻪ ﻣﺤﻠﻲ‪ ،‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ‬ ‫ﺷﺒﻜﻪ ‪ WAN‬ﻭ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻛﻨﺴﻮﻝ ﻭ ﻛﻤﻜﻲ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﻄﻠﺐ ﺑﺎ ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫ﻫﺎﻱ ﻓﻮﻕ ﺁﺷﻨﺎ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬ ‫ﺍﻧﻮﺍﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺭﻭﺗﺮ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺗﺼﺎﻻﺕ ﺭﻭﺗﺮ ﺑﻪ ﺩﻧﻴﺎﻱ ﺧﺎﺭﺝ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﻭ ﻣﻲ ﺗﻮﺍﻥ ﺁﻧﺎﻥ ﺭﺍ‬ ‫ﺑﻪ ﺳﻪ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩ‪:‬‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ‪ :‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﻳﻚ ﺭﻭﺗﺮ‬ ‫ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﻣﺘﺼﻞ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻨﮕﻮﻧﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﻌﻤﻮﻻ"‬ ‫ﻧﻮﻉ ﺧﺎﺻﻲ ﺍﺯ ﺍﺗﺮﻧﺖ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﻣﻤﻜﻦ ﺍﺳﺖ ﺍﺯ ﺳﺎﻳﺮ ﺗﻜﻨﻮﻟﻮﮊﻱ‬

‫ﻫﺎﻱ ‪ LAN‬ﻧﻈﻴﺮ ‪ Token Ring‬ﻭ ﻳﺎ ‪ ) ATM‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪Asynchronous‬‬ ‫‪ ( Transfer Mode‬ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﺺ ﺷﺒﻜﻪ ‪ : WAN‬ﺍﻳﻦ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﺍﺗﺼﺎﻻﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬

‫ﺍﺯ ﻃﺮﻳﻖ ﻳﻚ ﺍﺭﺍﺋﻪ ﺩﻫﻨـﺪﻩ ﺳﺮﻭﻳﺲ ﺑﻪ ﻳﻚ ﺳﺎﻳﺖ ﺧﺎﺹ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﻓﺮﺍﻫـــــﻢ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺍﺗﺼﺎﻻﺕ ﻓﻮﻕ ﻣﻤﻜﻦ ﺍﺳﺖ ﺍﺯ ﻧﻮﻉ ﺳﺮﻳﺎﻝ ﻭ ﻳﺎ ﻫﺮ ﺗﻌﺪﺍﺩ ﺩﻳﮕﺮ ﺍﺯ‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪ WAN‬ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺮﺧﻲ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪ ، WAN‬ﺑﻪ‬ ‫ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﺧﺎﺭﺟﻲ ﻧﻈﻴﺮ ‪ CSU‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮ ﺑﻪ ﺍﺗﺼﺎﻝ ﻣﺤﻠﻲ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ‬

‫ﺳﺮﻭﻳﺲ ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ ﺍﺗﺼﺎﻻﺕ ‪ ، WAN‬ﻣﻤﻜﻦ ﺍﺳﺖ ﺭﻭﺗﺮ‬ ‫ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻣﺘﺼﻞ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻛﻨﺴﻮﻝ ﻭ ﻛﻤﻜﻲ ‪ :‬ﻋﻤﻠﻜﺮﺩ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﺪﻳﺮﻳﺘﻲ ﻣﺘﻔﺎﻭﺕ ﺍﺯ ﺳﺎﻳﺮ‬ ‫ﺍﺗﺼﺎﻻﺕ ﺍﺳﺖ ‪ .‬ﺍﺗﺼﺎﻻﺕ ‪ LAN‬ﻭ ‪ ، WAN‬ﻣﺴﻮﻟﻴﺖ ﺍﻳﺠﺎﺩ ﺍﺗﺼﺎﻻﺕ ﺷﺒﻜﻪ ﺍﻱ ﺑﻪ‬

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‫ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻓﺮﻳﻢ ﻫﺎ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﻧﺪ ﻭﻟﻲ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﺪﻳﺮﻳﺘﻲ ﻳﻚ ﺍﺗﺼﺎﻝ ﻣﺒﺘﻨﻲ‬ ‫ﺑﺮ ﻣﺘﻦ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻭ ﺍﺷﻜﺎﻝ ﺯﺩﺍﺋﻲ ﺭﻭﺗﺮ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﭘﻮﺭﺕ ﻫﺎﻱ‬

‫ﻛﻤﻜﻲ ) ‪ ( auxilliary‬ﻭ ﻛﻨﺴﻮﻝ )‪ ( console‬ﺩﻭ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ‬ ‫ﻣﺪﻳﺮﻳﺖ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﭘﻮﺭﺕ ﻫﺎ‪ ،‬ﺍﺯ ﻧﻮﻉ ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﺮﻳﺎﻝ ﻏﻴﺮﻫﻤﺰﻣﺎﻥ‬ ‫‪ EIA-232‬ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺑﻪ ﻳﻚ ﭘﻮﺭﺕ ﺍﺭﺗﺒﺎﻃﻲ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ‬

‫ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺍﺯ ﻳﻚ ﺑﺮﻧﺎﻣﻪ ﺷﺒﻴﻪ ﺳﺎﺯ ﺗﺮﻣﻴﻨﺎﻝ ﺑﺮ ﺭﻭﻱ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﻚ‬ ‫ﺍﺭﺗﺒﺎﻁ ﻣﺒﺘﻨﻲ ﺑﺮ ﻣﺘﻦ ﺑﺎ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﻣﺪﻳﺮﺍﻥ ﺷﺒﻜﻪ ﻣﻲ ﺗﻮﺍﻧﻨﺪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺍﺯ ﺍﺭﺗﺒﺎﻁ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻣﺪﻳﺮﻳﺖ ﻭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪.‬‬ ‫ﺷﻜﻞ ﺯﻳﺮ ﺍﻧﻮﺍﻉ ﺍﺗﺼﺎﻻﺕ ﻳﻚ ﺭﻭﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺍﻧﻮﺍﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻳﻚ ﺭﻭﺗﺮ ) ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ (‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻓﻮﻕ ﺁﺷﻨﺎ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬ ‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﺪﻳﺮﻳﺖ‬

‫ﭘﻮﺭﺕ ﻫﺎﻱ ﻛﻨﺴﻮﻝ ﻭ ﻛﻤﻜﻲ ﺑﻪ ﻣﻨﺰﻟﻪ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﺪﻳﺮﻳﺘﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﻣﺪﻳﺮﻳﺖ ﻭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﺮﻳﺎﻝ ﻏﻴﺮﻫﻤﺰﻣﺎﻥ‬ ‫ﺑﻪ ﻋﻨﻮﺍﻥ ﭘﻮﺭﺕ ﻫﺎﻱ ﺷﺒﻜﻪ ﺍﻱ ﻃﺮﺍﺣﻲ ﻧﺸﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺮﺍﻱ ﭘﻴﻜﺮﻳﻨﺪﻱ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ ﺍﺯ ﻳﻜﻲ ﺍﺯ‬

‫ﭘﻮﺭﺕ ﻫﺎﻱ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﻌﻤﻮﻻ" ﺑﺮﺍﻱ ﭘﻴﻜﺮﻳﻨﺪﻱ ﺍﻭﻟﻴﻪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ‬ ‫ﺗﻮﺻﻴﻪ ﻣﻲ ﮔﺮﺩﺩ ﭼﺮﺍﻛﻪ ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎ ﻣﻤﻜﻦ ﺍﺳﺖ ﺩﺍﺭﺍﻱ ﻳﻚ ﭘﻮﺭﺕ ﻛﻤﻜﻲ ﻧﺒﺎﺷﻨﺪ‪.‬‬ ‫ﺯﻣﺎﻧﻲ ﻛﻪ ﺭﻭﺗﺮ ﺑﺮﺍﻱ ﺍﻭﻟﻴﻦ ﻣﺮﺗﺒﻪ ﻭﺍﺭﺩ ﻣﺪﺍﺭ ﻭ ﻳﺎ ﺳﺮﻭﻳﺲ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻋﺪﻡ ﻭﺟﻮﺩ‬ ‫ﭘﺎﺭﺍﻣﺘﺮﻫﺎﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺪﻩ ‪ ،‬ﺍﻣﻜﺎﻥ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻫﻴﭻ ﺷﺒﻜﻪ ﺍﻱ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﺑﺮﺍﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻭ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺍﻭﻟﻴﻪ ﺭﻭﺗﺮ ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﻚ ﺗﺮﻣﻴﻨﺎﻝ ﻭ ﻳﺎ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻛﻪ ﺑﻪ‬

‫ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﭘﺲ ﺍﺯ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ ‪،‬‬ ‫ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ﭘﻴﻜﺮﺑﻨﺪﻱ‪ ،‬ﺗﻨﻈﻴﻤﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪ .‬ﭘﺲ ﺍﺯ ﭘﻴﻜﺮﺑﻨﺪﻱ‬ ‫ﺭﻭﺗﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﻭ ﻳﺎ ﻛﻤﻜﻲ‪ ،‬ﺯﻣﻴﻨﻪ ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮ ﺑﻪ ﺷﺒﻜﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﻜﺎﻝ‬

‫ﺯﺩﺍﺋﻲ ﻭ ﻳﺎ ﻣﺎﻧﻴﺘﻮﺭﻳﻨﮓ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻧﺤﻮﻩ ﺍﺗﺼﺎﻝ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ‬

‫ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ ‪ ،‬ﺑﻪ ﻳﻚ ﻛﺎﺑﻞ ‪ rollover‬ﻭ ﻳﻚ‬

‫ﺁﺩﺍﭘﺘﻮﺭ ‪ RJ-45 to DB-9‬ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ ﺑﻪ ﻫﻤﺮﺍﻩ ﺁﺩﺍﭘﺘﻮﺭﻫﺎﻱ ﻣﻮﺭﺩ‬ ‫ﻧﻴﺎﺯ ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺍﺭﺍﺋﻪ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﺗﺮﻣﻴﻨﺎﻝ ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺎﺩﺭ‬ ‫ﺑﻪ ﺣﻤﺎﻳﺖ ﺍﺯ ﺷﺒﻴﻪ ﺳﺎﺯﻱ ﺗﺮﻣﻴﻨﺎﻝ ‪ VT100‬ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺷﺒﻴﻪ ﺳﺎﺯ‬ ‫ﺗﺮﻣﻴﻨﺎﻝ ﻧﻈﻴﺮ ‪ HyperTerminal‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲﮔﺮﺩﺩ‪.‬‬

‫ﺑﺮﺍﻱ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺮﺍﺣﻞ ﺯﻳﺮ ﺭﺍ ﺩﻧﺒﺎﻝ ﻧﻤﻮﺩ‪:‬‬ ‫•‬

‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺷﺒﻴﻪ ﺳﺎﺯﻱ ﺗﺮﻣﻴﻨﺎﻝ ﺑﺮ ﺭﻭﻱ ﻛﺎﻣﭙﻴﻮﺗﺮ ) ﺍﻧﺘﺨﺎﺏ ﺷﻤﺎﺭﻩ ﭘﻮﺭﺕ‬

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‫ﺍﺗﺼﺎﻝ ﻛﺎﻧﻜﺘﻮﺭ ‪ RJ-45‬ﻛﺎﺑﻞ ‪ rollover‬ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺭﻭﺗﺮ‬

‫ﻣﻨﺎﺳﺐ ﻭ ‪( ...‬‬ ‫•‬ ‫•‬

‫ﺍﺗﺼﺎﻝ ﺳﺮ ﺩﻳﮕﺮ ﻛﺎﺑﻞ ‪ rollover‬ﺑﻪ ﺁﺩﺍﭘﺘﻮﺭ ‪RJ-45 to DB-9‬‬

‫ﺍﺗﺼﺎﻝ ﺁﺩﺍﭘﺘﻮﺭ ‪ DB-9‬ﺑﻪ ﻛﺎﻣﭙﻴﻮﺗﺮ‬

‫ﺷﻜﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﻛﺎﺑﻞ ‪ rollover‬ﻧﺸﺎﻥ‬ ‫ﻣﻲ ﺩﻫﺪ ‪:‬‬

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‫ﺍﺗﺼﺎﻝ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﺭﻭﺗﺮ‬

‫ﺑﺮﺍﻱ ﻣﺪﻳﺮﻳﺖ ﻭ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ﺭﻭﺗﺮ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﻳﻚ ﻣﻮﺩﻡ ﺭﺍ ﺑﻪ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﻭ ﻳﺎ‬ ‫ﻛﻤﻜﻲ ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪ .‬ﺷﻜﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮ ﺑﻪ ﻳﻚ ﻣﻮﺩﻡ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ ‪:‬‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺭﻭﺗﺮ ﺍﺯ ﻃﺮﻳﻖ ﻣﻮﺩﻡ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺷﻜﺎﻝ ﺯﺩﺍﺋﻲ ﺭﻭﺗﺮ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﻧﺴﺒﺖ ﺑﻪ ﭘﻮﺭﺕ ﻛﻤﻜﻲ ﺗﺮﺟﻴﺢ ﺩﺍﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺑﻪ ﺻﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﭘﻴﺎﻡ ﻫﺎﻱ ﺧﻄﺎﺀ‪ ،‬ﺍﺷﻜﺎﻝ‬

‫ﺯﺩﺍﺋﻲ ﻭ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺍﺯ ﭘﻮﺭﺕ ﻛﻨﺴﻮﻝ ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﻛﻪ ﺳﺮﻭﻳﺲ ﻫﺎﻱ‬

‫ﺷﺒﻜﻪ ﻓﻌﺎﻝ ﻧﺸﺪﻩ ﻭ ﻳﺎ ﺑﺎ ﻣﺸﻜﻞ ﻣﻮﺍﺟﻪ ﺷﺪﻩ ﺍﻧﺪ ﻧﻴﺰ ﻣﻲ ﺗﻮﺍﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﭘﻮﺭﺕ‬ ‫ﻛﻨﺴﻮﻝ ﮔﺰﻳﻨﻪ ﺍﻱ ﻣﻨﺎﺳﺐ ﺑﺮﺍﻱ ﺑﺎﺯﻳﺎﻓﺖ ﺭﻣﺰ ﻋﺒﻮﺭ ﻭ ﺳﺎﻳﺮ ﻣﺸﻜﻼﺕ ﻏﻴﺮﻗﺎﺑﻞ ﭘﻴﺶ ﺑﻴﻨﻲ ﻣﻲ‬ ‫ﺑﺎﺷﺪ‪.‬‬ ‫ﺍﺗﺼﺎﻝ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪LAN‬‬ ‫ﺩﺭ ﺍﻛﺜﺮ ﻣﺤﻴﻂ ﻫﺎﻱ ‪ ، LAN‬ﺭﻭﺗﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ Ethernet‬ﻭ ﻳﺎ ‪Fast‬‬ ‫‪ Ethernet‬ﺑﻪ ﺷﺒﻜﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺭﻭﺗﺮ ﻫﻤﺎﻧﻨﺪ ﻳﻚ ﻣﻴﺰﺑﺎﻥ ﺍﺳﺖ ﻛﻪ‬

‫ﺑﺎ ﺷﺒﻜﻪ ‪ LAN‬ﺍﺯ ﻃﺮﻳﻖ ﻳﻚ ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ‬ ‫ﺍﺗﺼﺎﻝ ﺍﺯ ﻳﻚ ﻛﺎﺑﻞ ‪ straight-through‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ‪ ،‬ﺍﺗﺼﺎﻝ‬

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‫ﺍﺗﺮﻧﺖ ﺭﻭﺗﺮ ﻣﺴﺘﻘﻴﻤﺎ"ﺑﻪ ﻛﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻳﺎ ﺭﻭﺗﺮ ﺩﻳﮕﺮﻱ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﺍﺯ‬

‫ﻳﻚ ﻛﺎﺑﻞ ‪ Crossover‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺕ ﻋﺪﻡ ﺍﺳﺘﻔﺎﺩﻩ ﺻﺤﻴﺢ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ‪ ،‬ﻣﻤﻜﻦ ﺍﺳﺖ ﺭﻭﺗﺮ ﻭ ﻳﺎ ﺳﺎﻳﺮ ﺗﺠﻬﻴﺰﺍﺕ‬ ‫ﺷﺒﻜﻪ ﺍﻱ ﺑﺎ ﻣﺸﻜﻞ ﻣﻮﺍﺟﻪ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﺍﺗﺼﺎﻝ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪WAN‬‬ ‫ﺍﺗﺼﺎﻻﺕ ‪ WAN‬ﺩﺍﺭﺍﻱ ﺍﻧﻮﺍﻉ ﻣﺨﺘﻠﻔﻲ ﺑﻮﺩﻩ ﻭ ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺳﺮﻭﻳﺲ ﻫﺎﻱ ‪ WAN‬ﻣﻌﻤﻮﻻ" ﺍﺯ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﮔﺎﻥ ﺳﺮﻭﻳﺲ ﺍﺟﺎﺭﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺧﻄﻮﻁ‬ ‫‪ leased‬ﻭ ﻳﺎ ‪ packet-switched‬ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﺍﻧﻮﺍﻉ ﻣﺘﻔﺎﻭﺕ ﺍﺗﺼﺎﻻﺕ ‪WAN‬‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺑﺮﺍﻱ ﻫﺮ ﻳﻚ ﺍﺯ ﺍﻧﻮﺍﻉ ﺳﺮﻭﻳﺲ ﻫﺎﻱ ‪ ، WAN‬ﺩﺳﺘﮕﺎﻩ ﻣﺸﺘﺮﻱ ) ﺍﻏﻠﺐ ﻳﻚ ﺭﻭﺗﺮ ﺍﺳﺖ ( ﺑﻪ‬

‫ﻣﻨﺰﻟﻪ ﻳﻚ ‪ ) DTE‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ ( data terminal equipment‬ﺭﻓﺘﺎﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﭘﺎﻳﺎﻧﻪ ﻓﻮﻕ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪ ) DCE‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪data circuit-terminating‬‬ ‫‪ (equipment‬ﻛﻪ ﻣﻌﻤﻮﻻ" ﻳﻚ ﻣﻮﺩﻡ ﻭ ﻳﺎ ‪ ) CSU/DSU‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪channel‬‬ ‫‪ ( service unit/data service unit‬ﻣﻲ ﺑﺎﺷﺪ ﺑﻪ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻣﺘﺼﻞ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺑﺮﺍﻱ ﺗﺒﺪﻳﻞ ﺩﺍﺩﻩ ﺍﺯ ‪ DTE‬ﺑﻪ ﻳﻚ ﺷﻜﻞ ﻗﺎﺑﻞ ﻗﺒﻮﻝ ﺑﺮﺍﻱ ﺍﺭﺍﺋﻪ‬ ‫ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ‪ ، WAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ ) WAN‬ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ (‬

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‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺳﺮﻳﺎﻝ‪ ،‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺭﻭﺗﺮ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﻫﺎﻱ‬ ‫‪ WAN‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺍﻱ ﺍﻧﺘﺨﺎﺏ ﻛﺎﺑﻞ ﺳﺮﻳﺎﻝ ﻣﻨﺎﺳﺐ‪ ،‬ﺑﺮﺭﺳﻲ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﭘﻴﺸﻨﻬﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ :‬ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ ﻣﻤﻜﻦ ﺍﺳﺖ ﺍﺯ ﻛﺎﻧﻜﺘﻮﺭﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺑﺮﺍﻱ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﺳﺮﻳﺎﻝ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺑﺮﺧﻲ ﺭﻭﺗﺮﻫﺎ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ‬

‫ﺳﺮﻳﺎﻝ ‪ smart‬ﻭ ﻳﺎ ﻳﻚ ﺍﺗﺼﺎﻝ ‪ DB-60‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﻧﻮﻉ ﺍﺗﺼﺎﻝ ﺷﺒﻜﻪ ‪ :‬ﺁﻳﺎ ﺷﺒﻜﻪ ﺑﻪ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪ DCE‬ﻭ ﻳﺎ ‪ DTE‬ﻣﺘﺼﻞ ﺍﺳﺖ؟ ‪DCE‬‬

‫ﻭ ‪ DTE‬ﺩﻭ ﻧﻮﻉ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺳﺮﻳﺎﻝ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺩﺳﺘﮕﺎﻩ ﻫﺎ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ‬ ‫ﺑﺎ ﻳﻜﺪﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺍﺭﺍﺋﻪ ﺳﻴﮕﻨﺎﻝ ﻛﻼﻙ ﺑﺮﺍﻱ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﺮ ﺭﻭﻱ‬ ‫ﮔﺬﺭﮔﺎﻩ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﻭﻳﮋﮔﻲ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ‪ DTE‬ﻣﺤﺴﻮﺏ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﻧﻮﻉ ﺳﻴﮕﻨﺎﻟﻴﻨﮓ ‪ :‬ﺑﺮﺍﻱ ﻫﺮ ﺩﺳﺘـﮕﺎﻩ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﻚ ﺍﺳﺘــﺎﻧﺪﺍﺭﺩ ﺳﺮﻳﺎﻝ ﻣﺘﻔـــﺎﻭﺕ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﻫﺮ ﺍﺳـــﺘﺎﻧﺪﺍﺭﺩ‪ ،‬ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﻛﺎﺑﻞ ﺭﺍ ﺗﻌﺮﻳﻒ ﻭ ﻧﻮﻉ‬

‫ﻛﺎﻧﻜﺘﻮﺭﻫﺎﻱ ﺩﻭ ﺳﺮ ﻛﺎﺑﻞ ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺭﻭﺗﺮ ﻭ ﺟﺎﻳﮕﺎﻩ ﺁﻥ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪WAN‬‬ ‫ﺭﻭﺗﺮ ﻳﻜﻲ ﺍﺯ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﺷﺒﻜﻪ ﺍﻱ ﻣﻬﻢ ﻭ ﺣﻴﺎﺗﻲ ﺍﺳﺖ ﻛﻪ ﺍﺯ ﺁﻥ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ‬ ‫‪ LAN‬ﻭ ‪ WAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﻄﻠﺐ ﭘﺲ ﺍﺯ ﺁﺷﻨﺎﺋﻲ ﺍﻭﻟﻴﻪ ﺑﺎ ﺭﻭﺗﺮ‪ ،‬ﺑﺎ ﺟﺎﻳﮕﺎﻩ ﺁﻥ‬ ‫ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ WAN‬ﺁﺷﻨﺎ ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪.‬‬ ‫ﺁﺷﻨﺎﺋﻲ ﺍﻭﻟﻴﻪ ﺑﺎ ﺭﻭﺗﺮ‬

‫ﺭﻭﺗﺮ ﻳﻚ ﻧﻮﻉ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺧﺎﺹ ﺍﺳﺖ ﻛﻪ ﺩﺍﺭﺍﻱ ﻋﻨﺎﺻﺮ ﻣﺸﺎﺑﻪ ﻳﻚ ﻛﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‬

‫ﺷﺨﺼﻲ ﻧﻈﻴﺮ ﭘﺮﺩﺍﺯﻧﺪﻩ‪ ،‬ﺣﺎﻓﻈﻪ‪ ،‬ﺧﻄﻮﻁ ﺩﺍﺩﻩ ﻭ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺨﺘﻠﻒ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ‬ ‫ﺍﺳﺖ‪ .‬ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺑﺴﻴﺎﺭ ﺧﺎﺹ ﻛﻪ ﻋﻤﻮﻣﺎ" ﻧﻤﻲ ﺗﻮﺍﻥ ﺁﻧﺎﻥ ﺭﺍ ﺗﻮﺳﻂ‬

‫ﻛﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺨﺼﻲ ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪ ،‬ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﻣﺜﻼ" ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﻣﻲ ﺗﻮﺍﻥ ﺩﻭ‬ ‫ﺷﺒﻜﻪ ﺭﺍ ﺑﻪ ﻳﻜﺪﻳﮕﺮ ﻣﺘﺼﻞ ﺗﺎ ﺩﺭ ﺍﺩﺍﻣﻪ ﺍﻣﻜﺎﻥ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﺁﻧﺎﻥ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮ‪،‬‬ ‫ﻫﻤﭽﻨﻴﻦ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻳﻚ ﺷﺒﻜﻪ ﺑﻪ ﺷﺒﻜﻪ ﺍﻱ ﺩﻳﮕﺮ ﺭﺍ ﺗﻌﻴﻴﻦ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﻛﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺑﻪ ﻳﻚ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻧﻴﺎﺯ ﺩﺍﺭﻧﺪ‪ ،‬ﺍﻳﻦ‬

‫ﻭﺿﻌﻴﺖ ﺩﺭ ﺭﻭﺗﺮﻫﺎ ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﻭ ﺁﻧﺎﻥ ﻧﻴﺰ ﺟﻬﺖ ﺍﺟﺮﺍﻱ ﻓﺎﻳﻞ ﻫﺎﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺑﻪ ﻳﻚ‬ ‫ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻛﻪ ﺑﻪ ﺁﻥ ‪ ) IOS‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪Internetwork Operating System‬‬

‫‪ ( software‬ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻧﻴﺎﺯ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪ .‬ﻓﺎﻳﻞ ﻫﺎﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺷﺎﻣﻞ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ‬

‫ﻫﺎ ﻭ ﭘﺎﺭﺍﻣﺘﺮﻫﺎﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺑﺮ ﺍﺳﺎﺱ ﺁﻧﺎﻥ ﺗﺮﺍﻓﻴﻚ ﻭﺭﻭﺩﻱ ﻭ ﺧﺮﻭﺟﻲ ﺭﻭﺗﺮ ﻛﻨــــــﺘﺮﻝ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻣﺜﻼ" ﺭﻭﺗﺮﻫﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﻭﺗﻜﻞ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺗﺨﺎﺫ ﺗﺼﻤﻴﻢ‬

‫ﻣﻨﺎﺳﺐ ﺩﺭ ﺧﺼﻮﺹ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺣﺎﻓﻈﻪ ﻫﺎﻱ ‪ ، NVRAM ، RAM‬ﻓﻠﺶ‪ ROM ،‬ﻭ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﻬﻤﺘﺮﻳﻦ ﻋﻨﺎﺻﺮ ﺩﺍﺧﻠﻲ‬ ‫ﻳﻚ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﺷﻨﺪ ﻛﻪ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﻫﺮ ﻳﻚ ﺍﺯ ﺁﻧﺎﻥ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

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‫ﺣﺎﻓﻈﻪ ‪ ) RAM‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ : ( random access memory‬ﺣﺎﻓﻈﻪ ‪RAM‬‬ ‫ﻛﻪ ﺑﻪ ﺁﻥ ‪ ) DRAM‬ﺣﺎﻓﻈﻪ ‪ RAM‬ﭘﻮﻳﺎ ( ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﻲﺷﻮﺩ ﺩﺍﺭﺍﻱ ﺧﺼﻮﺻﻴﺎﺕ ﻭ ﻭﻇﺎﻳﻒ‬ ‫ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﺪ ‪:‬‬ ‫•‬

‫ﺫﺧﻴﺮﻩ ﺟﺪﺍﻭﻝ ﺭﻭﺗﻴﻨﮓ‬

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‫ﻧﮕﻬﺪﺍﺭﻱ ‪Cache ARP‬‬

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‫ﻧﮕﻬﺪﺍﺭﻱ ‪fast-Switching cache‬‬

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‫ﻧﮕﻬﺪﺍﺭﻱ ﻭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﺍﺯ ﺻﻒ ﻫﺎﻱ ﺣﺎﻭﻱ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ‬

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‫ﺍﺭﺍﺋﻪ ﺣﺎﻓﻈﻪ ﻣﻮﻗﺖ ﺑﺮﺍﻱ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺩﺭ ﺯﻣﺎﻥ ﺭﻭﺷﻦ ﻛﺮﺩﻥ ﺭﻭﺗﺮ‬

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‫ﻋﺪﻡ ﻧﮕﻬﺪﺍﺭﻱ ﺍﻃﻼﻋﺎﺕ ﭘﺲ ﺍﺯ ﺧﺎﻣﻮﺵ ﻛﺮﺩﻥ ﻭ ﻳﺎ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻣﺠﺪﺩ ﺭﻭﺗﺮ‬

‫ﺣﺎﻓﻈﻪ ‪ ) NVRAM‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪nonvolatile random-access‬‬ ‫‪ : ( memory‬ﺣﺎﻓﻈﻪ ‪ NVRAM‬ﻳﺎ ﻏﻴﺮﻓﺮﺍﺭ ﺩﺍﺭﺍﻱ ﺧﺼﺎﻳﺺ ﻭ ﻭﻇﺎﻳﻒ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﺪ‬ ‫‪:‬‬ ‫•‬

‫ﻣﺤﻞ ﻧﮕﻬﺪﺍﺭﻱ ﻓﺎﻳﻞ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ‬

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‫ﻧﮕﻬﺪﺍﺭﻱ ﺍﻃﻼﻋﺎﺕ ﭘﺲ ﺍﺯ ﺧﺎﻣﻮﺵ ﻛﺮﺩﻥ ﻭ ﻳﺎ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻣﺠﺪﺩ ﺭﻭﺗﺮ‬

‫ﺣﺎﻓﻈﻪ ﻓﻠﺶ ‪ :‬ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﺩﺍﺭﺍﻱ ﺧﺼﺎﻳﺺ ﻭ ﻭﻇﺎﻳﻒ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﺪ‪:‬‬ ‫•‬

‫ﻧﮕﻬﺪﺍﺭﻱ ‪ ) IOS‬ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ (‬

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‫ﺑﻬﻨﮕﺎﻡ ﺳﺎﺯﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺑﺪﻭﻥ ﺿﺮﻭﺭﺕ ﺗﻌﻮﻳﺾ ﻭ ﻳﺎ ﺟﺎﻳﮕﺰﻳﻨﻲ ﺗﺮﺍﺷﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ‬ ‫ﺑﺮ ﺭﻭﻱ ﭘﺮﺩﺍﺯﻧﺪﻩ‬

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‫ﻧﮕﻬﺪﺍﺭﻱ ﺍﻃﻼﻋﺎﺕ ﭘﺲ ﺍﺯ ﺧﺎﻣﻮﺵ ﻛﺮﺩﻥ ﻭ ﻳﺎ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻣﺠﺪﺩ ﺭﻭﺗﺮ‬

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‫ﻗﺎﺑﻠﻴﺖ ﺫﺧﻴﺮﻩ ﭼﻨﺪﻳﻦ ﻧﺴﺨﻪ ﺍﺯ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ‪IOS‬‬

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‫ﺍﻣﻜﺎﻥ ﺣﺬﻑ ﺍﻃﻼﻋﺎﺕ ) ﻳﻚ ﻧﻮﻉ ﺧﺎﺹ ﺍﺯ ﺣﺎﻓﻈﻪ ﻫﺎﻱ ‪ ROM‬ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺣﺬﻑ‬ ‫ﺍﻟﻜﺘﺮﻭﻧﻴﻜﻲ ﺍﻃﻼﻋﺎﺕ‪( EEPROM :‬‬

‫ﺣﺎﻓﻈﻪ ‪ ) ROM‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ ،( Read-only memory‬ﺣﺎﻓﻈﻪ ‪ ROM‬ﻭ ﻳﺎ ﻓﻘﻂ‬ ‫ﺧﻮﺍﻧﺪﻧﻲ ﺩﺍﺭﺍﻱ ﺧﺼﺎﻳﺺ ﻭ ﻭﻇﺎﻳﻒ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﺪ‪:‬‬ ‫•‬

‫ﻧﮕﻬﺪﺍﺭﻱ ﺩﺳﺘﻮﺭﺍﻟﻌﻤﻞ ﻫﺎﻱ ﻻﺯﻡ ﺑﺮﺍﻱ ﺍﺷﻜﺎﻝ ﺯﺩﺍﺋﻲ ﻭ ﺍﺟﺮﺍﻱ ﺑﺮﻧﺎﻣﻪ ‪POST‬‬ ‫) ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪( power-on self test‬‬

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‫ﺫﺧﻴﺮﻩ ﺑﺮﻧﺎﻣﻪ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﺭﻭﺗﺮ ﻣﻮﺳﻮﻡ ﺑﻪ ‪ bootstrap‬ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺍﻭﻟﻴﻪ ﺳﻴﺴﺘﻢ‬ ‫ﻋﺎﻣﻞ‬

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‫ﺗﻌﻮﻳﺾ ﺗﺮﺍﺷﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺑﺮﺩ ﺍﺻﻠﻲ ﺩﺭ ﺻﻮﺭﺕ ﻧﻴﺎﺯ ﺑﻪ ﺍﺭﺗﻘﺎﺀ ﻧﺮﻡ ﺍﻓﺰﺍﺭ‬

‫ﺫﺧﻴﺮﻩ ﺷﺪﻩ‬ ‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ‪ :‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﺩﺍﺭﺍﻱ ﺧﺼﺎﻳﺺ ﻭ ﻭﻇﺎﻳﻒ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬ ‫•‬

‫ﺭﻭﺗﺮ ﺭﺍ ﺑﻪ ﺷﺒﻜﻪ ﻣﺘﺼﻞ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ) ﻭﺭﻭﺩ ﻭ ﺧﺮﻭﺝ ﻓﺮﻳﻢ ﻫﺎ(‪.‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﻣﻤﻜﻦ ﺍﺳﺖ ﺑﺮ ﺭﻭﻱ ﺑﺮﺩ ﺍﺻﻠﻲ ﻭ ﻳﺎ ﺑﻪ ﻋﻨﻮﺍﻥ ﻣﺎﮊﻭﻝ ﻫﺎﻱ ﺟﺪﺍﮔﺎﻧﻪ‬

‫ﺍﺭﺍﺋﻪ ﮔﺮﺩﻧﺪ ‪.‬‬ ‫ﺟﺎﻳﮕﺎﻩ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ LAN‬ﻭ ‪WAN‬‬ ‫ﺑﺎ ﺍﻳﻦ ﻛﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺭﻭﺗﺮ ﺑﺮﺍﻱ ﺗﻘﺴﻴﻢ ) ‪ ( Segmentation‬ﻳﻚ ﺷﺒﻜﻪ ﻣﺤﻠﻲ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ﻭﻟﻲ ﻣﻬﻤﺘﺮﻳﻦ ﻛﺎﺭﺑﺮﺩ ﺁﻥ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﺷﺒﻜﻪ ﺍﻱ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ‬ ‫‪ WAN‬ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺷﻜﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺩﺭﻳﻚ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺩﺭﻳﻚ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ) ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﻜﻮ (‬

‫ﺍﺯ ﺗﻜﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ‪ WAN‬ﺩﺭ ﺍﻛﺜﺮ ﻣﻮﺍﺭﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻳﻜﺪﻳﮕﺮ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ ﻭ ﺭﻭﺗﺮﻫﺎ ﺑﺎ ﺍﺗﺼﺎﻻﺕ ﻣﺒﺘﻲ ﺑﺮ ‪ WAN‬ﺑﺎ ﻳﻜﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺭﻭﺗﺮﻫﺎ ﻣﺴﺌﻮﻟﻴﺖ ﺍﻳﺠﺎﺩ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ﺩﺍﺧﻠﻲ ﺑﺰﺭﮒ ) ﺍﻳﻨﺘﺮﺍﻧﺖ ( ﻭ ﻳﺎ‬

‫ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﻭ ﺩﺭ ﻻﻳﻪ ﺳﻮﻡ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ) ﺍﺗﺨﺎﺫ‬

‫ﺗﺼﻤﻴﻢ ﺑﺮ ﺍﺳﺎﺱ ﺁﺩﺭﺱ ﻫﺎﻱ ﺷﺒﻜﻪ (‪.‬‬ ‫ﺍﻧﺘﺨﺎﺏ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ ﻭ ﺳﻮﺋﻴﭽﻴﻨﮓ ﻓﺮﻳﻢ ﻫﺎ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﻨﺎﺳﺐ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ‬ ‫ﻭﻇﺎﻳﻒ ﻳﻚ ﺭﻭﺗﺮ ﻣﺤﺴﻮﺏ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﻭﻇﺎﻳﻒ ﻓﻮﻕ ﺟﺪﺍﻭﻝ‬

‫ﺭﻭﺗﻴﻨﮕﻲ ﺭﺍ ﺍﻳﺠﺎﺩ ) ﺍﻳﺴﺘﺎ ﻭ ﻳﺎ ﭘﻮﻳﺎ ( ﺗﺎ ﺑﻪ ﻛﻤﻚ ﺁﻥ ﺍﻗﺪﺍﻡ ﺑﻪ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺷﺒﻜﻪ ﺑﺎ ﺳﺎﻳﺮ‬ ‫ﺭﻭﺗﺮﻫﺎ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﻳﻚ ﻣﺪﻳﺮ ﺷﺒﻜﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻣﺴﻴﺮﻫﺎﻱ ﺍﻳﺴﺘﺎ‪ ،‬ﺍﻃﻼﻋﺎﺕ ﺟﺪﺍﻭﻝ‬ ‫ﺭﻭﺗﻴﻨﮓ ﺭﺍ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﻣﺪﻳﺮﻳﺖ ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﻋﻤﻮﻣﺎ" ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺟﺪﺍﻭﻝ ﺭﻭﺗﻴﻨﮓ‬ ‫ﺑﻪ ﺻﻮﺭﺕ ﭘﻮﻳﺎ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﻚ ﭘﺮﻭﺗﻜﻞ ﺭﻭﺗﻴﻨﮓ ﺫﺧﻴﺮﻩ ﻭ ﺑﻬﻨﮕﺎﻡ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻣﺴﺌﻮﻟﻴﺖ‬

‫ﭘﺮﻭﺗﻜﻞ ﺭﻭﺗﻴﻨﮓ ‪ ،‬ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺗﻮﭘﻮﻟﻮﮊﻱ ﺷﺒﻜﻪ ) ﻣﺴﻴﺮ( ﺑﺎ ﺳﺎﻳﺮ ﺭﻭﺗﺮﻫﺎ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫ﻳﻚ ﺷﺒﻜﻪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺎﻳﺮ ﺷﺒﻜﻪ ﻫﺎ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺩﺭﺳﺘﻲ ﭘﻴﻜﺮﺑﻨﺪﻱ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ‬ ‫ﭼﻨﻴﻦ ﺷﺒﻜﻪ ﻫﺎﺋﻲ ﺍﻣﻜﺎﻧﺎﺕ ﺯﻳﺮ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪:‬‬ ‫•‬ ‫•‬

‫ﺁﺩﺭﺱ ﺩﻫﻲ ﭘﻴﻮﺳﺘﻪ ﻭ ﺳﺎﺯﮔﺎﺭ‬ ‫ﺍﻧﺘﺨﺎﺏ ﺑﻬﺘﺮﻳﻦ ﻣﺴﻴﺮ‬

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‫ﺭﻭﺗﻴﻨﮓ ﺍﻳﺴﺘﺎ ﻭ ﻳﺎ ﭘﻮﻳﺎ‬

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‫ﺳﻮﺋﻴﭽﻴﻨﮓ‬

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‫ﺁﺩﺭﺱ ﻫﺎﺋﻲ ﻛﻪ ﺑﻴﺎﻧﮕﺮ ﺗﻮﭘﻮﻟﻮﮊﻱ ﻫﺎﻱ ﺷﺒﻜﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺟﺎﻳﮕﺎﻩ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪WAN‬‬

‫ﺷﺒﻜﻪ ﻫﺎﻱ ‪ WAN‬ﺩﺭ ﻻﻳﻪ ﻓﻴﺰﻳﻜﻲ ﻭ ‪ data link‬ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻣﻄﻠﺐ ﻓﻮﻕ ﺑﺪﻳﻦ ﻣﻌﻨﻲ ﻧﻤﻲ ﺑﺎﺷﺪ ﻛﻪ ﭘﻨﺞ ﻻﻳﻪ ﺩﻳﮕﺮ ﻣﺪﻝ ﻣﺮﺟﻊ ‪ OSI‬ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ‬ ‫‪ WAN‬ﺟﺎﻳﮕﺎﻫﻲ ﻧﺪﺍﺭﻧﺪ ‪ .‬ﻋﺒﺎﺭﺕ ﻓﻮﻕ ﺑﺮ ﺍﻳﻦ ﻧﻜﺘﻪ ﻣﻬﻢ ﺗﺎﻛﻴﺪ ﻣﻲ ﻧﻤﺎﻳﺪ ﻛﻪ ﺧﺼﺎﻳﺼﻲ ﻛﻪ‬

‫ﻳﻚ ﺷﺒﻜﻪ ‪ WAN‬ﺭﺍ ﺍﺯ ‪ LAN‬ﻣﺘﻤﺎﻳﺰ ﻣﻲ ﻧﻤﺎﻳﺪ ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ ﻓﻴﺰﻳﻜﻲ ﻭ ‪link data‬‬ ‫ﺣﻀﻮﺭ ﻣﻮﺛﺮ ﻭ ﻛﺎﻣﻼ" ﻣﺸﻬﻮﺩﻱ ﺭﺍ ﺩﺍﺭﻧﺪ‪ .‬ﺑﻪ ﻋﺒﺎﺭﺕ ﺩﻳﮕﺮ‪ ،‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎ ﻭ ﭘﺮﻭﺗﻜﻞ ﻫﺎﻱ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ WAN‬ﻭ ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ ﺍﻭﻝ ﻭ ﺩﻭﻡ ﻣﺘﻔﺎﻭﺕ ﺑﺎ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎ ﻭ‬

‫ﭘﺮﻭﺗﻜﻞ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ﻭ ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ ﻣﺸﺎﺑﻪ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﻻﻳﻪ ﻓﻴﺰﻳﻜﻲ ‪ ،WAN‬ﺍﻳﻨﺘﺮﻓﻴﺲ ﺑﻴﻦ ‪ ) DTE‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ‬

‫‪data terminal‬‬

‫‪ ( equipment‬ﻭ ‪ ) DCE‬ﺑﺮﮔﺮﻓﺘﻪ ﺍﺯ ‪ ( data circuit equipment‬ﺭﺍ ﺗﺸﺮﻳﺢ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻋﻤﻮﻣﺎ" ‪ DCE ،‬ﻳﻚ ﺍﺭﺍﺋﻪ ﺩﻫﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻭ ‪ DTE‬ﺩﺳﺘﮕﺎﻩ ﺿﻤﻴﻤﻪ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﺑﻪ ﻋﺒﺎﺭﺕ ﺩﻳﮕﺮ ‪ ، DTE‬ﺩﺳﺘﮕﺎﻩ ﻛﺎﺭﺑﺮ ﺑﺎ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺖ ﻛﻪ ﺑﻪ ﻟﻴﻨﻚ ‪ WAN‬ﻣﺘﺼﻞ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻣﺪﻝ‪ ،‬ﺳﺮﻭﻳﺲ ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﻪ ‪ DTE‬ﺍﺯ ﻃﺮﻳﻖ ﻳﻚ ﻣﻮﺩﻡ ﻭ ﻳﺎ‬ ‫‪ CSU/DSU‬ﺩﺭ ﺩﺳﺘﺮﺱ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﺩ‪.‬‬ ‫ﻭﻇﻴﻔﻪ ﺍﺻﻠﻲ ﻳﻚ ﺭﻭﺗﺮ‪ ،‬ﺭﻭﺗﻴﻨﮓ ﺍﺳﺖ ﻭ ﺭﻭﺗﻴﻨﮓ ﺩﺭ ﻻﻳﻪ ﺷﺒﻜﻪ ﻭ ﻳﺎ ﻻﻳﻪ ﺳﻮﻡ ﻣﺪﻝ ﻣﺮﺟﻊ‬

‫‪ OSI‬ﻣﺤﻘﻖ ﻣﻲ ﮔﺮﺩﺩ ﻭﻟﻲ ﺍﮔﺮ ﻳﻚ ﺷﺒﻜﻪ ‪ WAN‬ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ ﺍﻭﻝ ﻭ ﺩﻭﻡ ﻣﺪﻝ ﻣﺮﺟﻊ‬ ‫‪ OSI‬ﻓﻌﺎﻟﻴﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ ،‬ﺁﻳﺎ ﺭﻭﺗﺮ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﻭ ﻳﺎ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪ WAN‬ﺍﺳﺖ‬ ‫؟ ﺩﺭ ﭘﺎﺳﺦ ﺑﻪ ﺳﻮﺍﻝ ﻓﻮﻕ ﻣﻲ ﺑﺎﻳﺴﺖ ﮔﻔﺖ ﻛﻪ ﻫﺮ ﺩﻭ ﮔﺰﻳﻨﻪ ﺩﺭﺳﺖ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻳﻚ ﺭﻭﺗﺮ‬

‫ﻣﻤﻜﻦ ﺍﺳﺖ ﺍﻧﺤﺼﺎﺭﺍ" ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻧﻤﺎﻳﺪ ﻭ ﻳﺎ ﻣﻤﻜﻦ‬ ‫ﺍﺳﺖ ﻣﻨﺤﺼﺮﺍ" ﻭﻇﻴﻔﻪ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪ WAN‬ﺭﺍ ﺩﺭ ﺷﺒﻜﻪ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ ﻭ ﻳﺎ ﺩﺭ ﺑﺮﺧﻲ‬

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‫ﻣﻮﺍﺭﺩ ﻛﻪ ﺩﺭ ﻣﺤﺪﻭﺩﻩ ﻣﺮﺯﻱ ﺑﻴﻦ ﻳﻚ ﺷﺒﻜﻪ ‪ LAN‬ﻭ ‪ WAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺩﺭ ﻳﻚ‬

‫ﻟﺤﻈﻪ ﻣﻲﺗﻮﺍﻧﺪ ﻫﻢ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﻭ ﻫﻢ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪WAN‬‬

‫ﻭﻇﺎﻳﻒ ﻣﺤﻮﻟﻪ ﺭﺍ ﺍﻧﺠﺎﻡ ﺩﻫﺪ ‪.‬‬ ‫ﻳﻜﻲ ﺍﺯ ﻭﻇﺎﻳﻒ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ ، WAN‬ﻣﺴﻴﺮﺩﻫﻲ ﺑﺴﺘﻪ ﻫﺎﻱ ﺍﻃﻼﻋﺎﺗﻲ ﺩﺭ ﻻﻳﻪ ﺳﻮﻡ‬

‫ﺍﺳﺖ ﻭﻟﻲ ﺭﻭﺗﺮ ﺩﺭ ﻳﻚ ﺷﺒﻜﻪ ﻣﺤﻠﻲ ﻧﻴﺰ ﺩﺍﺭﺍﻱ ﭼﻨﻴﻦ ﻣﺴﺌﻮﻟﻴﺘﻲ ﺍﺳﺖ ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻧﻤﻲ ﺗﻮﺍﻥ‬

‫ﺭﻭﺗﻴﻨﮓ ﺭﺍ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﻭﻇﻴﻔﻪ ﺍﺧﺘﺼﺎﺻﻲ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ WAN‬ﺩﺭ ﻧﻈﺮ‬ ‫ﮔﺮﻓﺖ‪ .‬ﺯﻣﺎﻧﻲ ﻛﻪ ﻳﻚ ﺭﻭﺗﺮ ﺍﺯ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎ ﻭ ﭘﺮﻭﺗﻜﻞ ﻫﺎﻱ ﻣﺮﺗﺒﻂ ﺑﺎ ‪ WAN‬ﺩﺭ ﻻﻳﻪ ﻫﺎﻱ‬

‫ﻓﻴﺰﻳﻜﻲ ﻭ ‪ data link‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻭﻱ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﻚ ﺩﺳﺘﮕﺎﻩ ‪ WAN‬ﺩﺭ ﺷﺒﻜﻪ‬ ‫ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻭﻟﻴﻦ ﻭﻇﻴﻔﻪ ﺭﻭﺗﺮ ﺩﺭ ﻳﻚ ﺷﺒﻜﻪ ‪ WAN‬ﺭﻭﺗﻴﻨﮓ ﻧﻤﻲ ﺑﺎﺷﺪ ﻭ ﺍﮔﺮ‬

‫ﻗﺮﺍﺭ ﺍﺳﺖ ﺑﺮﺍﻱ ﺁﻥ ﻭﻇﻴﻔﻪ ﺍﻱ ﺍﺧﺘﺼﺎﺻﻲ ﺭﺍ ﺗﻌﺮﻳﻒ ﻧﻤﺎﺋﻴﻢ ﺑﻬﺘﺮ ﺍﺳﺖ ﮔﻔﺘﻪ ﺷﻮﺩ ﻛﻪ‬ ‫ﻣﺴﺌﻮﻟﻴﺖ ﺭﻭﺗﺮ ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪ ، WAN‬ﺍﺭﺍﺋﻪ ﺍﺗﺼﺎﻻﺕ ﻻﺯﻡ ﺑﻴﻦ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻣﺨﺘﻠﻒ‬ ‫‪ data link‬ﻭ ﻓﻴﺮﻳﻜﻲ ‪ WAN‬ﺍﺳﺖ‪.‬‬ ‫ﻣﺜﻼ" ﻳﻚ ﺭﻭﺗﺮ ﻣﻤﻜﻦ ﺍﺳﺖ ﺩﺍﺭﺍﻱ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ ISDN‬ﺑﺎﺷﺪ ﻛﻪ ﺍﺯ ﻛﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ ‪PPP‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ﻭ ﻫﻤﭽﻨﻴﻦ ﺩﺍﺭﺍﻱ ﻳﻚ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺳﺮﻳﺎﻝ ‪ T1‬ﺑﺎﺷﺪ ﻛﻪ ﺩﺭ ﺁﻥ ﺍﺯ ﻛﭙﺴﻮﻟﻪ‬

‫ﺳﺎﺯﻱ ‪ Frame Relay‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻭﺿﻌﻴﺘﻲ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﻧﺘﻘﺎﻝ ﺑﻴﺖ ﻫﺎ ﺍﺯ ﻳﻚ ﻧﻮﻉ ﺳﺮﻭﻳﺲ ) ﻧﻈﻴﺮ ‪ ( ISDN‬ﺑﻪ ﺳﺮﻭﻳﺲ ﺩﻳﮕﺮ )ﻧﻈﻴﺮ ‪ (T1‬ﻭ ﺗﻐﻴﻴﺮ‬ ‫ﻛﭙﺴﻮﻟﻪ ﺳﺎﺯﻱ ‪ data link‬ﺍﺯ ‪ PPP‬ﺑﻪ ‪ Frame Relay‬ﺑﺎﺷﺪ‪.‬‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎ ﻭ ﭘﺮﻭﺗﻜﻞ ﻫﺎﻱ ﻻﻳﻪ ﻓﻴﺰﻳﻜﻲ ﻭ ‪ data link‬ﺩﺭ ﺷﺒﻜﻪ ﻫﺎﻱ ‪WAN‬‬ ‫ﺑﺮﺧﻲﺍﺯ ﭘﺮﻭﺗﻜﻞ ﻫﺎ ﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻻﻳﻪ ﻓﻴﺰﻳﻜﻲ ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬

‫‪EIA/TIA-232‬‬ ‫‪EIA/TIA-449‬‬ ‫‪V.24‬‬ ‫‪V.35‬‬ ‫‪X.21‬‬ ‫‪G.703‬‬ ‫‪344‬‬

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EIA-530 ISDN T1, T3, E1, and E3 xDSL SONET (OC-3, OC-12, OC-48, OC-192) : ‫ ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‬data link ‫ﺑﺮﺧﻲ ﺍﺯ ﭘﺮﻭﺗﻜﻞ ﻫﺎ ﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻻﻳﻪ‬

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High-level data link control (HDLC) Frame Relay Point-to-Point Protocol (PPP) Synchronous Data Link Control (SDLC) Serial Line Internet Protocol (SLIP) X.25 ATM LAPB LAPD LAPF

345

‫ﺍﻧﻮﺍﻉ ﺭﻭﺗﺮ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮﻫﺎ ﺩﺭ ﺷﺒﮑﻪ ﺑﻪ ﺍﻣﺮﻱ ﻣﺘﺪﺍﻭﻝ ﺗﺒﺪﻳﻞ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﻳﮑﻲ ﺍﺯ ﺩﻻﻳﻞ ﻣﻬﻢ‬

‫ﮔﺴﺘﺮﺵ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ‪ ،‬ﺿﺮﻭﺭﺕ ﺍﺗﺼﺎﻝ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ) ﺍﻳﻨﺘﺮﻧﺖ ﻭ‬ ‫ﻳﺎ ﺳﺎﻳﺮ ﺳﺎﻳﺖ ﻫﺎ ﻱ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ ( ﺩﺭ ﻋﺼﺮ ﺣﺎﺿﺮ ﺍﺳﺖ‪ .‬ﻧﺎﻡ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ‬ ‫ﺭﻭﺗﺮﻫﺎ ‪ ،‬ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﮐﺎﺭﻱ ﺍﺳﺖ ﮐﻪ ﺁﻧﺎﻥ ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ‪ " :‬ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ‬

‫ﺷﺒﮑﻪ ﺍﻱ ﺩﻳﮕﺮ" ‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﺷﺮﮐﺖ ﺩﺍﺭﺍﻱ ﺷﻌﺒﻪ ﺍﻱ ﺩﺭ ﺗﻬﺮﺍﻥ ﻭ ﻳﮏ ﺩﻓﺘﺮ‬ ‫ﺩﻳﮕﺮ ﺩﺭ ﺍﻫﻮﺍﺯ ﺑﺎﺷﺪ ‪ ،‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺁﻧﺎﻥ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﮏ ﺧﻂ ‪leased‬‬ ‫)ﺍﺧﺘﺼﺎﺻﻲ( ﮐﻪ ﺑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺩﻓﺎﺗﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

‫ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﻫﺮ ﮔﻮﻧﻪ ﺗﺮﺍﻓﻴﮑﻲ ﮐﻪ ﻻﺯﻡ ﺍﺳﺖ ﺍﺯ ﻳﮏ ﺳﺎﻳﺖ ﺑﻪ ﺳﺎﻳﺖ ﺩﻳﮕﺮ ﺍﻧﺠﺎﻡ ﺷﻮﺩ ﺍﺯ‬ ‫ﻃﺮﻳﻖ ﺭﻭﺗﺮ ﻣﺤﻘﻖ ﺷﺪﻩ ﻭ ﺗﻤﺎﻣﻲ ﺗﺮﺍﻓﻴﮏ ﻫﺎﻱ ﻏﻴﺮﺿﺮﻭﺭﻱ ﺩﻳﮕﺮ ﻓﻴﻠﺘﺮ ﻭ ﺩﺭ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ‬ ‫ﻫﺰﻳﻨﻪ ﻫﺎﻱ ﻣﺮﺑﻮﻃﻪ‪ ،‬ﺻﺮﻓﻪ ﺟﻮﺋﻲ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺍﻧﻮﺍﻉ ﺭﻭﺗﺮﻫﺎ‬ ‫ﺭﻭﺗﺮﻫﺎ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻭ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩ‪:‬‬ ‫•‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ‪ :‬ﺭﻭﺗﺮﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﻧﺮﻡ‬ ‫ﺍﻓﺰﺍﺭﻫﺎﻱ ﺧﺎﺹ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺭﺍ ﺍﺟﺮﺍﺀ ﻣﻲ ﻧﻤﺎﻳﻨﺪ )ﺩﺭﺣﺎﻝ‬

‫ﺣﺎﺿﺮ ﺻﺮﻓﺎ" ﺑﻪ ﺻﻮﺭﺕ ‪ black box‬ﺑﻪ ﺁﻧﺎﻥ ﻧﮕﺎﻩ ﻣﻲ ﮐﻨﻴﻢ (‪.‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﻓﻮﻕ‪،‬‬ ‫ﻗﺎﺑﻠﻴﺖ ﺭﻭﺗﻴﻨﮓ ﺭﺍ ﺑﺮﺍﻱ ﺭﻭﺗﺮﻫﺎ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩﻩ ﺗﺎ ﺁﻧﺎﻥ ﻣﻬﻤﺘﺮﻳﻦ ﻭ ﺷﺎﻳﺪ ﺳﺎﺩﻩ ﺗﺮﻳﻦ‬ ‫ﻭﻇﻴﻔﻪ ﺧﻮﺩ ﮐﻪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﺷﺒﮑﻪ ﺩﻳﮕﺮ ﺍﺳﺖ ﺭﺍ ﺑﺨﻮﺑﻲ ﺍﻧﺠﺎﻡ ﺩﻫﻨﺪ‪.‬‬ ‫ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎ ﺗﺮﺟﻴﺢ ﻣﻲ ﺩﻫﻨﺪ ﮐﻪ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﻨﺪ‬

‫ﭼﺮﺍﮐﻪ ﺁﻧﺎﻥ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺭﻭﺗﺮﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‪ ،‬ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ﻭ ﺍﻋﺘﻤﺎﺩ ﭘﺬﻳﺮﻱ‬ ‫ﺑﻴﺸﺘﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻳﮏ ﻧﻤﻮﻧﻪ ﺭﻭﺗﺮ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪Cisco 2600 ) .‬‬

‫‪( Series Multiservice Platform‬‬

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‫ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ‬

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‫ﺭﻭﺗﺮﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ‪ :‬ﺭﻭﺗﺮﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺩﺍﺭﺍﻱ ﻋﻤﻠﮑﺮﺩﻱ ﻣﺸﺎﺑﻪ ﺑﺎ ﺭﻭﺗﺮﻫﺎﻱ‬ ‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺑﻮﺩﻩ ﻭ ﻣﺴﺌﻮﻟﻴﺖ ﺍﺻﻠﻲ ﺁﻧﺎﻥ ﻧﻴﺰ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ ﺷﺒﮑﻪ‬

‫ﺩﻳﮕﺮ ﺍﺳﺖ‪ .‬ﻳﮏ ﺭﻭﺗﺮ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﻣﻲ ﺗﻮﺍﻧﺪ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ ، NT‬ﻳﮏ ﺳﺮﻭﻳﺲ‬ ‫ﺩﻫﻨﺪﻩ ﻧﺖ ﻭﺭ ﻭ ﻳﺎ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻟﻴﻨﻮﮐﺲ ﺑﺎﺷﺪ‪ .‬ﺗﻤﺎﻣﻲ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻋﺎﻣﻞ‬

‫ﺷﺒﮑﻪ ﺍﻱ ﻣﻄﺮﺡ ‪،‬ﺩﺍﺭﺍﻱ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﺭﻭﺗﻴﻨﮓ ﺍﺯ ﻗﺒﻞ ﺗﻌﺒﻴﻪ ﺷﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺩﺭ ﺍﮐﺜﺮ ﻣﻮﺍﺭﺩ ﺍﺯ ﺭﻭﺗﺮﻫﺎ ﺑﻪ ﻋﻨﻮﺍﻥ ﻓﺎﻳﺮﻭﺍﻝ ﻭ ﻳﺎ ‪ gateway‬ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻻﺯﻡ ﺍﺳﺖ ﺑﻪ ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﺗﻔﺎﻭﺕ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺭﻭﺗﺮﻫﺎﻱ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‬

‫ﻭ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ‪ ،‬ﺍﺷﺎﺭﻩ ﮔﺮﺩﺩ ‪ :‬ﺩﺭ ﺍﮐﺜﺮ ﻣﻮﺍﺭﺩ ﻧﻤﻲ ﺗﻮﺍﻥ ﻳﮏ ﺭﻭﺗﺮ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ ﺭﺍ ﺟﺎﻳﮕﺰﻳﻦ‬ ‫ﻳﮏ ﺭﻭﺗﺮ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﻧﻤﻮﺩ‪ ،‬ﭼﺮﺍﮐﻪ ﺭﻭﺗﺮﻫﺎﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺩﺍﺭﺍﻱ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻻﺯﻡ ﻭ‬ ‫ﺍﺯ ﻗﺒﻞ ﺗﻌﺒﻴﻪ ﺷﺪﻩ ﺍﻱ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺑﻪ ﺁﻧﺎﻥ ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ ﻳﮏ ﻟﻴﻨﮏ ﺧﺎﺹ ‪WAN‬‬

‫)ﺍﺯ ﻧﻮﻉ ‪ ISDN ، Frame Relay‬ﻭ ﻳﺎ ‪ (ATM‬ﺭﺍ ﺧﻮﺍﻫﺪ ﺩﺍﺩ ‪.‬ﻳﮏ ﺭﻭﺗﺮ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‬ ‫) ﻧﻈﻴﺮ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻭﻳﻨﺪﻭﺯ ( ﺩﺍﺭﺍﻱ ﺗﻌﺪﺍﺩﻱ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺍﺳﺖ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ‬

‫ﻳﮏ ﺷﺒﮑﻪ ‪ LAN‬ﻣﺘﺼﻞ ﺷﺪﻩ ﻭ ﺳﺎﻳﺮ ﺍﺗﺼﺎﻻﺕ ﺑﻪ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ WAN‬ﺍﺯ ﻃﺮﻳﻖ ﺭﻭﺗﺮﻫﺎﻱ‬ ‫ﺳﺨﺖ ﻓﺰﺍﺭﻱ ‪ ،‬ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﻣﺜﺎﻝ ‪ : ١‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺩﻭ ﺷﺒﮑﻪ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻭ ﺍﺭﺗﺒﺎﻁ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‬

‫ﻓﺮﺽ ﮐﻨﻴﺪ ﺍﺯ ﻳﮏ ﺭﻭﺗﺮ ﻣﻄﺎﺑﻖ ﺷﮑﻞ ﺯﻳﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺩﻭ ﺷﺒﮑﻪ ‪ LAN‬ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻭ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ ﺭﻭﺗﺮ ﺩﺍﺩﻩ ﺍﻱ ﺭﺍ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺷﺒﮑﻪ ‪ LAN‬ﻭ ﻳﺎ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭﻳﺎﻓﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﭘﺲ ﺍﺯ ﺑﺮﺭﺳﻲ ﺁﺩﺭﺱ ﻣﺒﺪﺍﺀ ﻭ ﻣﻘﺼﺪ‪ ،‬ﺩﺍﺩﻩ ﺩﺭﻳﺎﻓﺘﻲ ﺭﺍ ﺑﺮﺍﻱ ﻫﺮ‬

‫ﻳﮏ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷﮑﻞ ﺯﻳﺮ ‪ ،‬ﺷﺒﮑﻪ ﺭﺍ‬

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‫ﺑﻪ ﺩﻭ ﺑﺨﺶ ﻣﺘﻔﺎﻭﺕ ﺗﻘﺴﻴﻢ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ ) .‬ﺩﻭ ﺷﺒﮑﻪ ﻣﺠﺰﺍﺀ (‪ .‬ﻫﺮ ﺷﺒﮑﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﻫﺎﺏ‬

‫ﺍﺳﺖ ﮐﻪ ﺗﻤﺎﻣﻲ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺑﻪ ﺁﻥ ﻣﺘﺼﻞ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﻋﻼﻭﻩ ﺑﺮ ﻣﻮﺍﺭﺩ ﻓﻮﻕ‪،‬‬ ‫ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺍﺭﺍﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﻫﺮ ﺷﺒﮑﻪ ﺑﻪ ﺁﻥ ﺑﻮﺩﻩ ﻭ ﺍﺯ‬

‫ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺩﻳﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﺭﻭﺗﺮ‬ ‫ﻗﺎﺩﺭ ﺍﺳﺖ ﺩﺍﺩﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﻪ ﻣﻘﺼﺪ ﺩﺭﺳﺖ‪ ،‬ﺍﺭﺳﺎﻝ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺜﺎﻝ ‪ :٢‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ‪LAN‬‬ ‫ﻓﺮﺽ ﮐﻨﻴﺪ ﺍﺯ ﻳﮏ ﺭﻭﺗﺮ ﻣﻄﺎﺑﻖ ﺷﮑﻞ ﺯﻳﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ‪ ،LAN‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ‬

‫ﻣﺪﻝ ﻓﻮﻕ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺑﺎ ﺭﻭﺗﺮ ﻣﻮﺟﻮﺩ ﻧﻈﻴﺮ ﻳﮏ ‪gateway‬‬ ‫ﺑﺮﺧﻮﺭﺩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﻫﺮ ﻳﮏ ﺍﺯ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ‪ LAN‬ﮐﻪ‬ ‫ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ )ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﻳﺎ ﻫﺮ ﻣﺤﻞ ﺧﺎﺭﺝ ﺍﺯ ﺷﺒﮑﻪ ‪ ( LAN‬ﺭﺍ ﺩﺍﺷﺘﻪ‬ ‫ﺑﺎﺷﻨﺪ‪ ،‬ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ ﺑﺮﺍﻱ ‪ gateway‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﺭﻭﺗﺮ ) ‪ ( gateway‬ﻧﺴﺒﺖ ﺑﻪ ﻣﺤﻞ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﺩﺍﺭﺍﻱ ﺁﮔﺎﻫﻲ ﻻﺯﻡ ﻣﻲ ﺑﺎﺷﺪ‪) .‬ﺩﺭ ﺯﻣﺎﻥ‬

‫ﺗﻨﻈﻴﻢ ﺧﺼﻠﺖ ﻫﺎﻱ ﭘﺮﻭﺗﮑﻞ ‪ TCP/IP‬ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﻣﺎﺷﻴﻦ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﻳﮏ‬ ‫ﺁﺩﺭﺱ ‪ IP‬ﺑﺮﺍﻱ ‪ gateway‬ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﻲ ﺷﻮﺩ (‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ‬ ‫ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﮐﺎﺭﺑﺮﺍﻥ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺩﺭ ﺷﺒﮑﻪ ‪ LAN‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

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‫ﻣﺜﺎﻝ ‪ :٣‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺩﻭ ﺩﻓﺘﺮ ﮐﺎﺭ‬

‫ﻓﺮﺽ ﮐﻨﻴﺪ‪ ،‬ﺑﺨﻮﺍﻫﻴـﻢ ﺍﺯ ﺭﻭﺗـــﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗــﺼﺎﻝ ﺩﻭ ﺩﻓﺘﺮ ﮐﺎﺭ ﻳﮏ ﺳﺎﺯﻣﺎﻥ ﺑﻪ ﻳﮑﺪﻳﮕﺮ‪،‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﺋﻴﻢ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻫﺮ ﻳﮏ ﺍﺯ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ‬

‫ﭘﺮﻭﺗﮑﻞ ‪ WAN‬ﻧﻈﻴﺮ ‪ ISDN‬ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻋﻤﻼ"‪ ،‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ‬

‫ﮐﻪ ﺗﻮﺳﻂ ‪ ISP‬ﻣﺮﺑﻮﻃﻪ ﺍﺭﺍﺋﻪ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ‪ WAN‬ﺭﻭﺗﺮ ﻓﺮﺍﻫﻢ‬ ‫ﺷﺪﻩ ﻭ ﺍﺯ ﺁﻧﺠﺎ ﺳﻴﮕﻨﺎﻝ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﺷﺒﮑﻪ ‪ ISP‬ﻣﺮﺑﻮﻃﻪ ﺭﻓﺘﻪ ﻭ ﺳﺮ ﺩﻳﮕﺮ ﺁﻥ ﺑﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ‬

‫‪ WAN‬ﺭﻭﺗﺮ ﺩﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺭﻭﺗﺮﻫﺎ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﺎﻳﺖ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ‪WAN‬‬ ‫ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ‪ HDLC , Frame Relay , ATM‬ﻭ ﻳﺎ ‪ ، PPP‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﻣﻬﻤﺘﺮﻳﻦ ﻭﻳﮋﮔﻲ ﻫﺎﻱ ﻳﮏ ﺭﻭﺗﺮ ‪:‬‬ ‫•‬

‫ﺭﻭﺗﺮﻫﺎ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﻻﻳﻪ ﺳﻮﻡ ) ﻣﺪﻝ ﻣﺮﺟﻊ ‪ ( OSI‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺭﻭﺗﺮﻫﺎ ﻣﺎﺩﺍﻣﻴﮑﻪ ﺑﺮﻧﺎﻣﻪ ﺭﻳﺰﻱ ﻧﮕﺮﺩﻧﺪ ‪ ،‬ﺍﻣﮑﺎﻥ ﺗﻮﺯﻳﻊ ﺩﺍﺩﻩ ﺭﺍ ﻧﺨﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪.‬‬

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‫ﺍﮐﺜﺮ ﺭﻭﺗﺮﻫﺎﻱ ﻣﻬﻢ ﺩﺍﺭﺍﻱ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺍﺧﺘﺼﺎﺻﻲ ﺧﺎﺹ ﺧﻮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺭﻭﺗﺮﻫﺎ ﺍﺯ ﭘﺮﻭﺗﮑﻞ ﻫﺎﻱ ﺧﺎﺻﻲ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺿﺮﻭﺭﻱ ﺧﻮﺩ ) ﻣﻨﻈﻮﺭ‬ ‫ﺩﺍﺩﻩ ﻧﻴﺴﺖ (‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪.‬‬

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‫ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﻳﮏ ﺭﻭﺗﺮ ﺩﺭ ﺍﻳﻨﺘﺮﻧﺖ ‪ :‬ﻣﺴﻴﺮ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺑﺮﺍﻱ ﺍﻧﺠﺎﻡ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺗﻲ‬ ‫ﺑﻴﻦ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺭ ﺗﻤﺎﻣﻲ ﻣﺪﺕ ﺯﻣﺎﻥ ﺍﻧﺠﺎﻡ ﺗﺮﺍﮐﺶ ﺛﺎﺑﺖ ﻭ‬ ‫ﻳﮑﺴﺎﻥ ﻧﺒﻮﺩﻩ ﻭ ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﻭﺿﻌﻴﺖ ﺗﺮﺍﻓﻴﮏ ﻣﻮﺟﻮﺩ ﻭ ﺩﺭ ﺩﺳﺘﺮﺱ ﺑﻮﺩﻥ ﻣﺴﻴﺮ‪ ،‬ﺗﻐﻴﻴﺮ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ‬ ‫ﺳﻴﺴﮑﻮ ﻳﮑﻲ ﺍﺯ ﻣﻌﺘﺒﺮﺗﺮﻳﻦ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺭﻭﺗﺮ ﻭ ﺳﻮﺋﻴﭻ ﺩﺭ ﺳﻄﺢ ﺟﻬﺎﻥ ﺍﺳﺖ ﮐﻪ ﺍﺯ‬

‫ﻣﺤﺼﻮﻻﺕ ﺁﻥ ﺩﺭ ﻣﺮﺍﮐﺮ ﺷﺒﮑﻪ ﺍﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺍﻳﻦ ﺷﺮﮐﺖ ﺗﺎﮐﻨﻮﻥ ﻣﺪﻝ ﻫﺎﻱ‬ ‫ﻣﺘﻌﺪﺩﻱ ﺍﺯ ﺭﻭﺗﺮﻫﺎ ﺭﺍ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﻫﺎﻱ ﻣﺨﺘﻠﻔﻲ ﺗﻮﻟﻴﺪ ﻧﻤﻮﺩﻩ ﺍﺳﺖ ‪ .‬ﺳﺮﻱ ‪ ٢٥٠٠ ، ١٦٠٠‬ﻭ‬ ‫‪ ، ٢٦٠٠‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻧﻤﻮﻧﻪ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺭﻭﺗﺮﻫﺎﻱ ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺍﻳﻦ ﺷﺮﮐﺖ‬

‫ﺍﺯ ﺳﺮﻱ ‪ ٦٠٠‬ﺷﺮﻭﻉ ﻭ ﺗﺎ ﺳﺮﻱ ‪ ١٢٠٠٠‬ﺍﺩﺍﻣﻪ ﻣﻲ ﻳﺎﺑﺪ) ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ (‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﺑﺮﺧﻲ‬ ‫ﺍﺯ ﻧﻤﻮﻧﻪ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬ ‫ﺳﺮﻱ ‪٢٦٠٠‬‬

‫ﺳﺮﻱ ‪١٢٠٠٠‬‬

‫ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ‬

‫ﺗﻤﺎﻣﻲ ﺗﺠﻬﻴﺰﺍﺕ ﻓﻮﻕ‪ ،‬ﻧﺮﻡ ﺍﻓﺰﺍﺭ ﺧﺎﺻﻲ ﺭﺍ ﺑﺎ ﻧﺎﻡ ‪Internetwork Operating‬‬ ‫‪ System‬ﻭ ﻳﺎ ‪ IOS‬ﺍﺟﺮﺍﺀ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،IOS .‬ﻫﺴﺘﻪ ﺭﻭﺗﺮﻫﺎ ﻭﺍﮐﺜﺮﺳﻮﺋﻴﭻ ﻫﺎﻱ ﺗﻮﻟﻴﺪ ﺷﺪﻩ‬ ‫ﺗﻮﺳﻂ ﺳﻴﺴﮑﻮ‪ ،‬ﻣﺤﺴﻮﺏ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﻳﻦ ﺷﺮﮐﺖ ﺑﺎ ﺭﻋﺎﻳﺖ ﺍﺻﻞ ﻣﻬﻢ ﺳﺎﺯﮔﺎﺭﻱ ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻪ‬

‫ﻋﻨﻮﺍﻥ ﻳﮏ ﺍﺳﺘﺮﺍﺗﮋﻱ ﻣﻬﻢ ﺩﺭ ﺗﻮﻟﻴﺪ ﻭ ﺑﺎ ﻧﺎﻡ ‪ ،Fusion Cisco‬ﻧﺎﻡ ﺑﺮﺩﻩ ﻣﻲ ﺷﻮﺩ‪ ،‬ﻗﺼﺪ‬

‫ﺩﺍﺭﺩ ﻣﺤﺼﻮﻻﺕ ﺧﻮﺩ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﺗﻮﻟﻴﺪ ﻧﻤﺎﻳﺪ ﮐﻪ ﺗﻤﺎﻣﻲ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺳﻴﺴﮑﻮﻳﮏ ﺳﻴﺴﺘﻢ‬ ‫ﻋﺎﻣﻞ ﻳﮑﺴﺎﻥ ﺭﺍ ﺍﺟﺮﺍﺀ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻋﻨﺎﺻﺮ ﺍﺻﻠﻲ ﺩﺭ ﻳﮏ ﺭﻭﺗﺮ ﺳﻴﺴﮑﻮ‬ ‫•‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ) ‪. ( Interfaces‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ‬

‫ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎ ﺷﺎﻣﻞ ﭘﻮﺭﺕ ﻫﺎﻱ ﺳﺮﻳﺎﻝ ﻭ ﺍﺗﺮﻧﺖ ﻣﺨﺘﻠﻔﻲ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺭﻭﺗﺮ ﺑﻪ ﺷﺒﮑﻪ ‪ LAN‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺮ ﺭﻭﺗﺮ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﭘﺘﺎﻧﺴﻴﻞ‬ ‫ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‪ ،‬ﺩﺍﺭﺍﻱ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺖ‪ .‬ﺑﺮﺍﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ‬ ‫ﺭﻭﺗﺮ ﺍﺯ ﻳﮏ ﻧﺎﻡ ﺧﺎﺹ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺟﺪﻭﻝ ﺯﻳﺮ ﺑﺮﺧﻲ ﺍﺯ ﺍﺳﺎﻣﻲ ﻣﺘﺪﺍﻭﻝ ﺭﺍ‬ ‫ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ‬ ‫‪E0‬‬ ‫‪E1‬‬ ‫‪S0‬‬ ‫‪S1‬‬ ‫‪BRI 0‬‬ ‫‪BRI 1‬‬ ‫•‬

‫ﮐﺎﺭﺑﺮﺩ‬ ‫‪first Ethernet interface‬‬ ‫‪second Ethernet interface‬‬ ‫‪first Serial interface‬‬ ‫‪second Serial interface‬‬ ‫‪first B channel for Basic‬‬ ‫‪ISDN‬‬ ‫‪second B channel for Basic‬‬ ‫‪ISDN‬‬

‫ﺩﺭ ﺷﮑﻞ ﺯﻳﺮ ﻧﻤﺎﻱ ﭘﺸﺖ ﻳﮏ ﺭﻭﺗﺮ ﺳﻴﺴﮑﻮﺭﺍ ﺑﻪ ﻫﻤﺮﺍﻩ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺁﻥ‬ ‫ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ ‪ ) .‬ﻳﮏ ﺭﻭﺗﺮ ﺑﺎ ﻗﺎﺑﻠﻴﺖ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪.( ISDN‬‬

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‫ﻣﻨﺒﻊ ‪ :‬ﺳﺎﻳﺖ ﺳﻴﺴﮑﻮ‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﺭﻭﺗﺮ ﻓﻮﻕ ﺣﺘﻲ ﺩﺍﺭﺍﻱ ﺳﻮﮐﺖ ﻫﺎﻱ ﻣﺨﺘﺺ ﺗﻠﻔﻦ‬ ‫ﻧﻴﺰ ﻣﻲ ﺑﺎﺷﺪ‪ ،‬ﭼﺮﺍﮐﻪ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﺭﻭﺗﺮ ﻓﻮﻕ ﺍﺯ ﻧﻮﻉ ‪ ISDN‬ﻣﻲ ﺑﺎﺷﺪ‪،‬‬

‫ﻣﻲ ﺑﺎﻳﺴﺖ ﻳﮏ ﺗﻠﻔﻦ ﺩﻳﺠﻴﺘﺎﻟﻲ ﺭﺍ ﺑﻪ ﻳﮏ ﺧﻂ ‪ ISDN‬ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪ .‬ﺭﻭﺗﺮ ﻓﻮﻕ‬ ‫ﻋﻼﻭﻩ ﺑﺮ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ‪ ISDN‬ﺩﺍﺭﺍﻱ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺍﺗﺮﻧﺖ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺑﻪ ﻳﮏ‬ ‫ﺩﺳﺘﮕﺎﻩ ﺩﺭ ﺷﺒﮑﻪ ‪ LAN‬ﺍﺳﺖ ) ﻣﻌﻤﻮﻻ" ﻳﮏ ﻫﺎﺏ ﻭ ﻳﺎ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ (‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ‬ ‫ﮐﻪ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﭘﻮﺭﺕ ‪ uplink‬ﻳﮏ ﻫﺎﺏ ﻣﺘﺼﻞ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺳﻮﺋﻴﭻ‬

‫ﮐﻮﭼﮏ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺖ ﺭﻭﺗﺮ ﺭﺍ ﺩﺭ ﺣﺎﻟﺖ ﻫﺎﺏ‪ ،‬ﺗﻨﻈﻴﻢ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬ ‫‪351‬‬

‫ﺍﻳﻨﺘﺮﻓﻴﺲ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺘﺼﻞ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻭﺿﻌﻴﺖ ﺳﻮﺋﻴﭻ‬

‫ﺭﺍ ﺩﺭ ﺣﺎﻟﺖ ‪ node‬ﻗﺮﺍﺭ ﺩﺍﺩ ‪ .‬ﭘﻮﺭﺕ ‪ Config‬ﻭ ﻳﺎ ‪ Console‬ﺍﺯ ﻧﻮﻉ ﮐﺎﻧﮑﺘﻮﺭ‬ ‫‪ ) DB9‬ﻣﺎﺩﮔﻲ ( ﺑﻮﺩﻩ ﮐﻪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ﺧﺎﺹ ﺑﻪ ﭘﻮﺭﺕ ﺳﺮﻳﺎﻝ ﮐﺎﻣﭙﻴﻮﺗﺮ‬ ‫ﻣﺘﺼﻞ ﺗﺎ ﺍﻣﮑﺎﻥ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻣﺴﺘﻘﻴﻢ ﺭﻭﺗﺮ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﭘﺮﺩﺍﺯﻧﺪﻩ ) ‪ : ( CPU‬ﺗﻤﺎﻣﻲ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ ﺩﺍﺭﺍﻱ ﻳﮏ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺍﺻﻠﻲ‬

‫ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺍﺻﻠﻲ ﺩﺭ ﺭﻭﺗﺮ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﻧﺪ ‪ .‬ﭘﺮﺩﺍﺯﻧﺪﻩ ﺑﺎ‬

‫ﺗﻮﻟﻴﺪ ﻭﻗﻘﻪ ) ‪ ( IRQ‬ﺑﺎ ﺳﺎﻳﺮ ﻋﻨﺎﺻﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﺭﻭﺗﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ ﺍﺯ ﭘﺮﺩﺍﺯﻧﺪﻩ ﻫﺎﻱ ‪ RISC‬ﻣﻮﺗﻮﺭﻭﻻ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﻣﻌﻤﻮﻻ"‬ ‫ﺩﺭﺻﺪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﺮﺩﺍﺯﻧﺪﻩ ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺭﻭﺗﺮ ﻣﻌﻤﻮﻟﻲ ﺍﺯ ﺑﻴﺴﺖ ﺗﺠﺎﻭﺯ ﻧﻤﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫•‬

‫‪ ، IOS‬ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﺍﺻﻠﻲ ﺍﺟﺮﺍﺀ ﺷﺪﻩ ﺑﺮ ﺭﻭﻱ ﺭﻭﺗﺮﻫﺎ ﺍﺳﺖ‪ IOS .‬ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﻓﺮﺁﻳﻨﺪ ﻣﻮﺳﻮﻡ ﺑﻪ ‪ ،Bootup‬ﻟﻮﺩ ﻭﺩﺭ ﺣﺎﻓﻈﻪ ﻣﺴﺘﻘﺮﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺣﺠﻢ ‪ IOS‬ﻣﻌﻤﻮﻻ"‬ ‫ﺑﻴﻦ ﺩﻭ ﺗﺎ ﭘﻨﭻ ﻣﮕﺎﺑﺎﻳﺖ ﺑﻮﺩﻩ ﻭ ﺍﻳﻦ ﺣﺠﻢ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺭﻭﺗﺮ ﺍﺯ ﻣﻴﺰﺍﻥ‬ ‫ﺍﺷﺎﺭﻩ ﺷﺪﻩ ﻧﻴﺰ ﺗﺠﺎﻭﺯ ﻧﻤﺎﻳﺪ‪ .‬ﺁﺧﺮﻳﻦ ﻧﺴﺨﻪ ‪ IOS‬ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ‪ ،‬ﻧﺴﺨﻪ ﺷﻤﺎﺭﻩ‬

‫ﺩﻭﺍﺯﺩﻩ ﺍﺳﺖ ‪ .‬ﺷﺮﮐﺖ ﺳﻴﺴﮑﻮ ﺑﻪ ﺻﻮﺭﺕ ﻣﺴﺘﻤﺮ ﻭ ﺑﺎ ﻫﺪﻑ ﺑﺮﻃﺮﻑ ﻧﻤﻮﺩﻥ ﺑﺎﮒ ﻫﺎ‬ ‫ﻭ ﻳﺎ ﺍﻓﺰﻭﺩﻥ ﻗﺎﺑﻠﻴـﺖ ﻫﺎﻱ ﺍﺿﺎﻓﻪ ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺍﺋﻪ ﻧﺴﺨﻪ ﻫﺎﻱ ﺟﺎﻧﺒﻲ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺩﺭ ﻃﻲ ﻫﺮ ﻣﺎﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪.( ١٢ .٢ ، ١٢ . ١ ) .‬‬

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‫‪ ، IOS‬ﻗﺎﺑﻠﻴﺖ ﻫﺎ ﻭ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺭﺍ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺭﻭﺗﺮ ﺍﺭﺍﺋﻪ ﺩﺍﺩﻩ ﻭ ﻣﻲ ﺗﻮﺍﻥ‬ ‫ﺁﻥ ﺭﺍ ﺑﻬﻨﮕﺎﻡ ﻭ ﻳﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ‪ Backup‬ﮔﺮﻓﺘﻦ ﺁﻥ ﺭﺍ ﺍﺯ ﺭﻭﺗﺮ ‪ download‬ﻧﻤﻮﺩ‪.‬‬ ‫ﺩﺭ ﺳﺮﻱ ‪ ١٦٠٠٠‬ﺑﻪ ﺑﺎﻻ ‪ IOS ،‬ﺑﺮ ﺭﻭﻱ ﻳﮏ ﺣﺎﻓﻈﻪ ﻓﻠﺶ ﮐﺎﺭﺕ ‪ PCMCIA‬ﺍﺭﺍﺋﻪ‬

‫ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺣﺎﻓﻈﻪ ﻓﻮﻕ‪ ،‬ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﻳﮏ ﺍﺳﻼﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﭘﺸﺖ ﺭﻭﺗﺮ ﻣﺘﺼﻞ ﺷﺪﻩ‬

‫ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺁﻥ ‪ ،image IOS‬ﻟﻮﺩ ﻣﻲ ﮔﺮﺩﺩ‪ ، IOS image .‬ﻣﻌﻤﻮﻻ" ﻓﺸﺮﺩﻩ‬ ‫ﺑﻮﺩﻩ ﻭ ﺭﻭﺗﺮ ﻣﻲ ﺑﺎﻳﺴﺖ ﺁﻥ ﺭﺍ ﺍﺯ ﺣﺎﻟﺖ ﻓﺸﺮﺩﻩ ﺧﺎﺭﺝ ﻧﻤﺎﻳﺪ‪.‬‬

‫‪ IOS‬ﻳﮑﻲ ﺍﺯ ﻣﻬﻤﺘﺮﻳﻦ ﻋﻨﺎﺻﺮ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺭﻭﺗﺮ ﺑﻮﺩﻩ ﻭ ﺑﺪﻭﻥ ﻭﺟﻮﺩ ﺁﻥ ‪ ،‬ﺍﻣﮑﺎﻥ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺗﺮ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻘﺮﺍﺭ ‪ IOS‬ﺩﺭ ﺣﺎﻓﻈﻪ ﺿﺮﻭﺭﺗﻲ‬ ‫‪352‬‬

‫ﺑﻪ ﺩﺍﺷﺘﻦ ﻳﮏ ﮐﺎﺭﺕ ﻓﻠﺶ ) ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺧﺼﻮﺹ ﺭﻭﺗﺮﻫﺎﻱ ﺳﺮﻱ ‪ ١٦٠٠‬ﺍﺷﺎﺭﻩ‬

‫ﮔﺮﺩﻳﺪ( ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﻣﻲ ﺗﻮﺍﻥ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺍﮐﺜﺮ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﮑﻮ ﺭﺍ ﺑﻪ‬ ‫ﻣﻨﻈﻮﺭ ﻟﻮﺩ ‪ image IOS‬ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ tftp‬ﺷﺒﮑﻪ ﻭ ﻳﺎ ﺭﻭﺗﺮ‬ ‫ﺩﻳﮕﺮﻱ ﮐﻪ ﺩﺍﺭﺍﻱ ﭼﻨﺪﻳﻦ ‪ IOS image‬ﺑﺮﺍﻱ ﺭﻭﺗﺮﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺖ‪ ،‬ﺍﻧﺠﺎﻡ ﺩﺍﺩ‪.‬‬ ‫ﺩﺭ ﭼﻨﻴﻦ ﺭﻭﺗﺮﻫﺎﺋﻲ ﺍﺯ ﻳﮏ ﻓﻠﺶ ﮐﺎﺭﺕ ﺣﺎﻓﻈﻪ ﺑﺎ ﻇﺮﻓﻴﺖ ﺑﺎﻻ ﺑﻪ ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﺳﺎﺯﻱ‬

‫ﭼﻨﺪﻳﻦ ‪ ، ISO image‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫‪ ، Image RXBoot‬ﮐﻪ ﺑﻪ ﺁﻥ ‪ Bootloader‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ ‪ ،‬ﭼﻴﺰﻱ‬

‫ﺑﻴﺸﺘﺮ ﺍﺯ ﻳﮏ ﻧﺴﺨﻪ ﮐﻢ ﺣﺠﻢ ‪ IOS‬ﻧﺒﻮﺩﻩ ﮐﻪ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ ROM‬ﺭﻭﺗﺮ ﻣﺴﺘﻘﺮ‬

‫ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﺭﻭﺗﺮ ﺩﺍﺭﺍﻱ ﻓﻠﺶ ﮐﺎﺭﺕ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﻟﻮﺩ ‪IOS‬‬ ‫ﻧﺒﺎﺷﺪ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺭﺍ ﺑﮕﻮﻧﻪ ﺍﻱ ﺍﻧﺠﺎﻡ ﺩﺍﺩ ﮐﻪ ‪ RXBoot image‬ﺭﺍ‬ ‫ﻟﻮﺩ ﻧﻤﺎﻳﺪ‪ .‬ﺑﺎ ﻟﻮﺩ ﺑﺮﻧﺎﻣﻪ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﻧﺠﺎﻡ ﻋﻤﻠﻴﺎﺕ ﺍﻭﻟﻴﻪ ﻧﮕﻬﺪﺍﺭﻱ ﻭ ﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻭ‬ ‫ﻳﺎ ﻏﻴﺮ ﻓﻌﺎﻝ ﮐﺮﺩﻥ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﺁﻥ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺣﺎﻓﻈﻪ ‪ ، RAM‬ﻣﺤﻠﻲ ﺍﺳﺖ ﮐﻪ ﺭﻭﺗﺮ‪ IOS ،‬ﻭ ﻓﺎﻳﻞ ﻫﺎﻱ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺭﺍ ﺩﺭ ﺁﻥ ﻟﻮﺩ‬

‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻋﻤﻠﮑﺮﺩ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ﺣﺎﻓﻈﻪ ‪ RAM‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺖ‬ ‫)ﺍﺳﺘﻘﺮﺍﺭ ﺳﻴﺴﺘﻢ ﻋﺎﻣﻞ ﻭ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﮐﺎﺭﺑﺮﺩﻱ ﻣﺘﻔﺎﻭﺕ( ‪ .‬ﻣﻴﺰﺍﻥ ﺣﺎﻓﻈﻪ ‪ RAM‬ﻣﻮﺭﺩ‬ ‫ﻧﻴﺎﺯ ﻳﮏ ﺭﻭﺗﺮ‪ ،‬ﺑﺴﺘﮕﻲ ﺑﻪ ﺍﻧﺪﺍﺯﻩ ‪ image IOS‬ﻭ ﻓﺎﻳﻞ ﻫﺎﻱ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺩﺍﺭﺩ‪ .‬ﺩﺭ‬ ‫ﺍﮐﺜﺮ ﻣﻮﺍﺭﺩ ﻭ ﺩﺭ ﺭﻭﺗﺮﻫﺎﻱ ﮐﻮﭼﮏ ﺗﺮ ) ﺳﺮﻱ ‪ ،( ١٦٠٠‬ﺣﺎﻓﻈﻪ ‪ RAM‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‬

‫ﺑﻴﻦ ﺩﻭﺍﺯﺩﻩ ﺗﺎ ﺷﺎﻧﺰﺩﻩ ﻣﮕﺎﺑﺎﻳﺖ ﻣﻲ ﺑﺎﺷﺪ‪.‬ﺍﻳﻦ ﻭﺿﻌﻴﺖ ﺩﺭ ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮔﺘﺮ ﮐﻪ‬

‫ﺩﺍﺭﺍﻱ ‪ image ISO‬ﺑﻴﺸﺘﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﺑﻴﻦ ﺳﻲ ﻭ ﺩﻭ ﺗﺎ ﺷﺼﺖ ﻭ ﭼﻬﺎﺭ‬ ‫ﻣﮕﺎﺑﺎﻳﺖ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﺳﺘﻘﺮﺍﺭ ﺟﺪﺍﻭﻝ ﺭﻭﺗﻴﻨﮓ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ ، RAM‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺟﺪﺍﻭﻝ ﻓﻮﻕ ﺑﺰﺭﮒ ﻭ ﭘﻴﭽﻴﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮏ ﺭﻭﺗﺮ ﺑﺎ‬ ‫ﻣﻴﺰﺍﻥ ﺣﺎﻓﻈﻪ ‪ RAM‬ﻣﻨﺎﺳﺒﻲ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺣﺎﻓﻈﻪ ) ‪ . Non-Volatile RAM ) NVRAM‬ﺭﻭﺗﺮﻫﺎ ﺍﺯ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﺫﺧﻴﺮﻩ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﺍﻃﻼﻋﺎﺕ ﻣﺮﺑﻮﻁ ﺑﻪ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺧﻮﺩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫‪353‬‬

‫ﭘﺲ ﺍﺯ ﭘﻴﮑﺮﺑﻨﺪﻱ ﻳﮏ ﺭﻭﺗﺮ‪ ،‬ﻧﺘﺎﻳﺞ ﻭ ﻣﺎﺣﺼﻞ ﻋﻤﻠﻴﺎﺕ ﺩﺭ ‪ NVRAM‬ﺫﺧﻴﺮﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺣﺠﻢ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺣﺎﻓﻈﻪ ﻫﺎﻱ ‪ ،RAM‬ﺍﻧﺪﮎ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬ ‫ﻣﺜﻼ" ﺩﺭ ﺭﻭﺗﺮﻫﺎﻱ ﺳﺮﻱ ‪ ، ١٦٠٠‬ﺣﺠﻢ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺑﻪ ﻫﺸﺖ ﮐﻴﻠﻮﺑﺎﻳﺖ ﻣﻲ ﺭﺳﺪ‪ .‬ﺩﺭ‬ ‫ﺭﻭﺗﺮﻫﺎﻱ ﺑﺰﺭﮔﺘﺮﻱ ﻧﻈﻴﺮ ﺳﺮﻱ ‪ ،٢٦٠٠‬ﺣﺠﻢ ﺣﺎﻓﻈﻪ ‪ NVRAM‬ﺑﻪ ﺳﻲ ﻭ ﺩﻭ‬

‫ﮐﻴﻠﻮﺑﺎﻳـﺖ ﻣﻲ ﺭﺳﺪ ‪ .‬ﭘﺲ ﺍﺯ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻳﮏ ﺭﻭﺗﺮ ﻭ ﻟﻮﺩ ‪ ، ISO image‬ﻓﺎﻳﻞ‬

‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﺍﺯ ﺣﺎﻓﻈﻪ ‪ NVRAM‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺠﺎﻡ ﭘﻴﮑﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ‪ ،‬ﻟﻮﺩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺣﺎﻓﻈﻪ ﻫﺎ ‪ ،‬ﭘﺎﮎ ﻧﺨﻮﺍﻫﺪ ﺷﺪ )ﺣﺘﻲ ﺯﻣﺎﻧﻲ ﮐﻪ ﺭﻭﺗﺮ‬

‫‪ Reload‬ﻭ ﻳﺎ ﺧﺎﻣﻮﺵ ﺍﺳﺖ(‪.‬‬ ‫•‬

‫ﺣﺎﻓﻈﻪ ‪ ، ROM‬ﺍﺯ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﺭﻭﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺷﺎﻣﻞ ﺑﺮﺧﻲ ﮐﺪﻫﺎ ﻧﻈﻴﺮ ‪ Bootstrap‬ﻭ ‪ POST‬ﺑﻮﺩﻩ ﮐﻪ‬ ‫ﺗﺴﻬﻴﻼﺕ ﻻﺯﻡ ﺩﺭ ﺧﺼﻮﺹ ﺍﻧﺠﺎﻡ ﺗﺴﺖ ﻫﺎﻱ ﺍﻭﻟﻴﻪ ﻭ ﺭﺍﻩ ﺍﻧﺪﺍﺭﻱ ﺭﺍ ﺑﺮﺍﻱ ﺭﻭﺗﺮ‬

‫ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﻣﺤﺘﻮﻳﺎﺕ ﺍﻳﻦ ﺣﺎﻓﻈﻪ ﺭﺍ ﻧﻤﻲ ﺗﻮﺍﻥ ﺗﻐﻴﻴﺮ ﺩﺍﺩ ) ﻓﻘﻂ ﺧﻮﺍﻧﺪﻧﻲ(‪.‬‬ ‫ﺗﻤﺎﻣﻲ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺣﺎﻓﻈﻪ ‪ ROM‬ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺫﺧﻴﺮﻩ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫•‬

‫ﺣﺎﻓﻈﻪ ﻓﻠﺶ ‪ ،‬ﻫﻤﺎﻥ ﮐﺎﺭﺗﻲ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺑﺨﺶ ‪ IOS‬ﺑﻪ ﺁﻥ ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪.‬‬ ‫ﺍﻳﻦ ﺣﺎﻓﻈﻪ ﺍﺯ ﻧﻮﻉ‬

‫)‪(Electrical Eraseable Programmable Read Only Memory‬‬

‫‪، EEPROM‬‬

‫ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﮐﺎﺭﺕ ﻓﻮﻕ ﺍﺯ ﻃﺮﻳﻖ ﺍﺳﻼﺗﻲ ﮐﻪ ﺩﺭ ﭘﺸﺖ ﻳﮏ ﺭﻭﺗﺮ ﻗﺮﺍﺭ ﺩﺍﺭﺩ ﺑﻪ ﺭﻭﺗﺮ‬ ‫ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ ﻭ ﭼﻴﺰﻱ ﺑﻴﺶ ﺍﺯ ‪ image IOS‬ﺭﺍ ﺩﺭ ﺧﻮﺩ ﺫﺧﻴﺮﻩ ﻧﻤﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﻨﺴﻮﻝ ﺭﻭﺗﺮ ﻣﻲ ﺗﻮﺍﻥ ﺍﻃﻼﻋﺎﺗﻲ ﺭﺍ ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺣﺎﻓﻈﻪ ﻧﻮﺷﺖ ﻭ ﻳﺎ ﺍﻗﺪﺍﻡ‬ ‫ﺑﻪ ﺣﺬﻑ ﺑﺮﺧﻲ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺟﻮﺩ ﻧﻤﻮﺩ ‪ .‬ﺣﺠﻢ ﺣﺎﻓﻈﻪ ﻓﻮﻕ ﺍﺯ ‪ ٤‬ﻣﮕﺎﺑﺎﻳﺖ ﺩﺭ‬

‫ﺭﻭﺗﺮﻫﺎﻱ ﺳﺮﻱ ‪ ١٦٠٠‬ﺷﺮﻭﻉ ﺷﺪﻩ ﻭ ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﻣﺪﻝ ﺭﻭﺗﺮ‪ ،‬ﺍﻓﺰﺍﻳﺶ ﻣﻲ ﻳﺎﺑﺪ‪.‬‬ ‫•‬

‫ﺭﻳﺠﺴﺘﺮ ﭘﻴﮑﺮﺑﻨﺪﻱ ) ‪ ،( Configuration Register‬ﻧﻘﻄﻪ ﺷﺮﻭﻉ ﻓﺮﺁﻳﻨﺪ‬

‫ﺭﺍﻩ ﺍﻧﺪﺍﺯﻱ ‪ IOS‬ﺭﺍ ﻣﺸﺨﺺ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﻓﻠﺶ ﮐﺎﺭﺕ‪ ،‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ‪ tftp‬ﻭ ﻳﺎ‬ ‫ﺻﺮﻓﺎ" ﻟﻮﺩ ‪ . ( RXBoot image‬ﺭﻳﺠﺴﺘﺮ ﻓﻮﻕ‪ ،‬ﺷﺎﻧﺰﺩﻩ ﺑﻴﺘﻲ ﺍﺳﺖ‪.‬‬

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‫ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ‬ ‫ﺑﺮﺍﻱ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮﻫﺎﻱ ﺳﻴﺴﻜﻮ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﻪ ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮﺁﻧﺎﻥ‬ ‫ﺩﺳﺘﻴﺎﺑﻲ ﺩﺍﺷﺖ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﻚ ﺗﺮﻣﻴﻨﺎﻝ ﻭ ﻳﺎ ﺩﺳﺘﻴﺎﺑﻲ ﺍﺯﺭﺍﻩ ﺩﻭﺭ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬ ‫ﭘﺲ ﺍﺯ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺭﻭﺗﺮ‪ ،‬ﺩﺭ ﺍﻭﻟﻴﻦ ﺍﻗﺪﺍﻡ ﻣﻲ ﺑﺎﻳﺴﺖ ﻋﻤﻠﻴﺎﺕ ‪ logging‬ﺭﺍ ﺍﻧﺠﺎﻡ ﺗﺎ ﺯﻣﻴﻨﻪ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯﺳﺎﻳﺮ ﺩﺳﺘﻮﺭﺍﺕ ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺸﺎﻫﺪﻩ ﺁﺧﺮﻳﻦ ﻭﺿﻌﻴﺖ ﭘﻴﻜﺮﺑﻨﺪﻱ ﻭ ﻳﺎ ﺗﻐﻴﻴﺮ ﭘﻴﻜﺮﺑﻨﺪﻱ‬

‫ﺭﻭﺗﺮ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﻳﻚ ﻻﻳﻪ ﺍﻣﻨﻴﺘﻲ ﻣﻨﺎﺳﺐ‪ ،‬ﺍﻣﻜﺎﻥ ﺑﺎﻟﻔﻌﻞ ﻛﺮﺩﻥ ﭘﺘﺎﻧﺴﻴﻞ ﻫﺎﻱ ﺍﺭﺍﺋﻪ ﺷﺪﻩ‬

‫) ﺩﺳﺘﻮﺭﺍﺕ( ﺭﻭﺗﺮ ﺩﺭ ﺩﻭ ‪ mode‬ﻣﺘﻔﺎﻭﺕ ﻓﺮﺍﻫﻢ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫‪ : EXEC mode User‬ﺩﺭ ﺍﻳﻦ ‪ ، mode‬ﻋﻤﻮﻣﺎ" ﺩﺳﺘﻮﺭﺍﺗﻲ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ‬

‫ﺍﺟﺮﺍﺀ ﻧﻤﻮﺩ ﻛﻪ ﻣﺎﺣﺼﻞ ﺍﺟﺮﺍﻱ ﺁﻧﺎﻥ‪ ،‬ﻧﻤﺎﻳﺶ ﻭﺿﻌﻴﺖ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺍﺳﺖ ﻭ‬

‫ﻧﻤﻲ ﺗﻮﺍﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺠﻤﻮﻋﻪ ﺍﻣﻜﺎﻧﺎﺕ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺩﺭ ﺍﻳﻦ ‪ ، mode‬ﭘﻴﻜﺮﺑﻨﺪﻱ‬ ‫ﺭﻭﺗﺮ ﺭﺍ ﺗﻐﻴﻴﺮ ﺩﺍﺩ ‪.‬‬ ‫•‬

‫‪ : Privileged EXEC mode‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﻜﺎﻧﺎﺕ ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ‬

‫‪ ، mode‬ﻣﻲ ﺗﻮﺍﻥ ﭘﻴﻜﺮﺑﻨﺪﻱ ﺭﻭﺗﺮ ﺭﺍ ﺍﻧﺠﺎﻡ ﻭ ﺗﻐﻴﻴﺮﺍﺕ ﻻﺯﻡ ﺭﺍ ﺍﻋﻤﺎﻝ ﻧﻤﻮﺩ‪.‬‬ ‫ﭘﺲ ﺍﺯ ‪ login‬ﺑﻪ ﺭﻭﺗﺮ ‪ ،‬ﭘﺮﺍﻣﭙﺖ ‪ user Exec mode‬ﻧﺸﺎﻥ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ ‪ .‬ﺩﺳﺘﻮﺭﺍﺕ‬ ‫ﻣﻮﺟﻮﺩ ﺩﺭ ﺍﻳﻦ ‪ ، mode‬ﺯﻳﺮﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ‪Privileged EXEC mode‬‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﻛﺎﻣﻞ ﺩﺳﺘﻮﺭﺍﺕ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ‪Privileged‬‬

‫‪ EXEC mode‬ﻭﺍﺭﺩ ﺷﺪ‪ .‬ﺑﺎ ﺗﺎﻳﭗ ﺩﺳﺘﻮﺭ ‪ enable‬ﻭ ﻳﺎ ﺷﻜﻞ ﻣﺨﻔﻒ ﺷﺪﻩ ﺁﻥ ﻳﻌﻨﻲ‬ ‫‪ ، enu‬ﺁﻣﺎﺩﻩ ﻭﺭﻭﺩ ﺑﻪ ﺍﻳﻦ ‪ mode‬ﺧﻮﺍﻫﻴﻢ ﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﻛﻪ ﺑﺮﺍﻱ ﺭﻭﺗﺮ ﺭﻣﺰ ﻋﺒﻮﺭﻱ‬ ‫ﺗﻌﺮﻳﻒ ﺷﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﭘﺲ ﺍﺯ ﻧﻤﺎﻳﺶ ‪ password‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺭﻣﺰ ﻋﺒﻮﺭ ﺭﺍ ﻭﺍﺭﺩ ﻧﻤﻮﺩ‪.‬‬

‫ﭘﺲ ﺍﺯ ﺗﻜﻤﻴﻞ ﻓﺮﺁﻳﻨﺪ ‪ ، loggin‬ﺷﻜﻞ ﭘﺮﺍﻣﭙﺖ ) ‪ (prompt‬ﺗﻐﻴﻴﺮ ﻭ ﺑﻪ ﺻﻮﺭﺕ "‪ "#‬ﻧﺸﺎﻥ‬ ‫ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ ﻛﻪ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﻭﺭﻭﺩ ﺑﻪ ‪ Privileged EXEC mode‬ﻣﻲ ﺑﺎﺷﺪ‪global .‬‬

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‫‪ ، configuration mode‬ﻳﻜﻲ ﺍﺯ ﺣﺎﻻﺗﻲ ﺍﺳﺖ ﻛﻪ ﺻﺮﻓﺎ" ﺍﺯ ﻃﺮﻳﻖ ‪Privileged‬‬

‫‪ EXEC mode‬ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﺍﺳﺖ ‪ .‬ﺍﻣﻜﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺣﺎﻻﺕ ﺯﻳﺮ ﺍﺯ ﻃﺮﻳﻖ ‪global‬‬ ‫‪ configuration mode‬ﻭﺟﻮﺩ ﺩﺍﺭﺩ ‪:‬‬ ‫‪Interface‬‬ ‫‪Subinterface‬‬ ‫‪Line‬‬ ‫‪Router‬‬ ‫‪Route-map‬‬

‫•‬ ‫•‬ ‫•‬ ‫•‬ ‫•‬

‫ﺑﺮﺍﻱ ﺑﺮﮔﺸﺖ ﺑﻪ ‪ EXEC mode‬ﺍﺯ ﻃﺮﻳﻖ ‪ ، Privileged EXEC mode‬ﺍﺯ ﺩﺳﺘﻮﺭ‬ ‫‪ disable‬ﻭ ﻳﺎ ‪ Exit‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺑﺮﺍﻱ ﺑﺮﮔﺸﺖ ﺑﻪ ‪Privileged EXEC‬‬ ‫‪ mode‬ﺍﺯ ﻃﺮﻳﻖ ‪ ، global configuration mode‬ﺍﺯ ﺩﺳﺘﻮﺭ ‪ Exit‬ﻭ ﻳﺎ ﻛﻠﻴﺪﻫﺎﻱ‬ ‫‪ Ctrl-Z‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺍﺯ ﺗﺮﻛﻴﺐ ﻛﻠﻴﺪﻫﺎﻱ ‪ Ctrl-Z‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺮﺍﻱ ﺑﺮﮔﺸﺖ ﻣﺴﺘﻘﻴﻢ‬ ‫ﺑﻪ ‪ Privileged EXEC mode‬ﺍﺯ ﻫﺮﻳﻚ ﺍﺯ ﺣﺎﻻﺕ ﺯﻳﺮﻣﺠﻤﻮﻋﻪ ‪global‬‬ ‫‪ configuration mode‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

‫ﺑﺮﺍﻱ ﺗﻌﺮﻳﻒ ﺭﻣﺰ ﻋﺒﻮﺭ ﺟﻬﺖ ﻭﺭﻭﺩ ﺑﻪ ‪ ،Privileged EXEC mode‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬ ‫ﺩﺳﺘﻮﺭﺍﺕ ‪ enable password‬ﻭ ‪ enable secret‬ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺕ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ﻓﻮﻕ ‪ ،‬ﺍﻭﻟﻮﻳﺖ ﺑﺎ ﺩﺳﺘﻮﺭ ‪ enable secret‬ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

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‫ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﺍﻣﻜﺎﻧﺎﺕ ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ‬

، privileged EXEC mode ‫ ﻭ ﻳﺎ‬user EXEC mode ‫ﺑﺎ ﺗﺎﻳﭗ ﻋﻼﻣﺖ "?" ﺩﺭ‬ ‫ ﺩﺳﺘﻮﺭﺍﺕ ﺻﻔﺤﻪ ﺑﻪ‬. ‫ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‬mode ‫ﻟﻴﺴﺖ ﺩﺳﺘﻮﺭﺍﺕ ﻗﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﻫﺮ‬

‫ ﻣﻲ ﺗﻮﺍﻥ ﺻﻔﺤﺎﺕ ﺑﻌﺪﻱ ﺭﺍ ﻣﺸﺎﻫﺪﻩ‬enter ‫ﺻﻔﺤﻪ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﺷﺪﻩ ﻭ ﺑﺎ ﻓﺸﺮﺩﻥ ﻛﻠﻴﺪ‬ .‫ﻧﻤﻮﺩ‬ mode user EXEC ‫ﺩﺳﺘﻮﺭﺍﺕ‬ Exec commands: access-enable Create a temporary Access-List entry access-profile Apply userprofile to interface clear Reset functions connect Open a terminal connection disable Turn off privileged commands disconnect Disconnect an existing network connection Router>? enable Turn on privileged commands exit Exit from the EXEC help Description of the interactive help system lock Lock the terminal login Log in as a particular user logout Exit from the EXEC mrinfo Request neighbor and version information from a multicast router 357

mstat Show statistics after multiple multicast traceroutes mtrace Trace reverse multicast path from destination to source name-connection Name an existing network connection pad Open a X.29 PAD connection ping Send echo messages ppp Start IETF Point-to-Point Protocol (PPP) resume Resume an active network connection rlogin Open an rlogin connection show Show running system information slip Start Serial-line IP (SLIP) systat Display information about terminal lines telnet Open a telnet connection terminal Set terminal line parameters --More--

358

privileged EXEC mode ‫ﺩﺳﺘﻮﺭﺍﺕ‬ Exec commands: access-enable Create a temporary Access-List entry access-profile Apply userprofile to interface access-template Create a temporary Access-List entry bfe For manual emergency modes setting clear Reset functions clock Manage the system clock configure Enter configuration mode connect Open a terminal connection copy Copy configuration or #Router? image data debug Debugging functions (see also 'undebug') disable Turn off privileged commands disconnect Disconnect an existing network connection enable Turn on privileged commands erase Erase flash or configuration memory exit Exit from the EXEC help Description of the interactive help system lock Lock the terminal login Log in as a particular 359

user logout Exit from the EXEC mrinfo Request neighbor and version information from a multicast router mstat Show statistics after multiple multicast traceroutes mtrace Trace reverse multicast path from destination to source name-connection Name an existing network connection no Disable debugging functions pad Open a X.29 PAD connection ping Send echo messages ppp Start IETF Point-to-Point Protocol (PPP) --More-‫ ﻳﻚ ﻧﻤﻮﻧﻪ ﻣﺜﺎﻝ ) ﺗﻨﻈﻴﻢ ﺳﺎﻋﺖ‬، ‫ﺑﺮﺍﻱ ﺁﺷﻨﺎﺋﻲ ﺑﺎ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ ﺭﻭﺗﺮ‬

: ‫ﺭﻭﺗﺮ ( ﺭﺍ ﺑﺎ ﻫﻢ ﺩﻧﺒﺎﻝ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‬

‫ ﺗﺎﻳﭗ ﻋﻼﻣﺖ "?" ﺑﻪ ﻣﻨﻈﻮﺭ ﺁﮔﺎﻫﻲ ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ﻣﻮﺟﻮﺩ ) ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬: ‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ‬

•

‫ ﺑﺮﺭﺳﻲ ﮔﺮﺍﻣﺮ ﺩﺳﺘﻮﺭ ﻭ ﺍﻳﻦ ﻛﻪ ﺯﻣﺎﻥ ﺭﺍ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﭼﻪ ﻓﺮﻣﺘﻲ ﻭﺍﺭﺩ‬: ‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ‬

•

( clock ‫ﺩﺳﺘﻮﺭ‬

. ‫ﻧﻤﻮﺩ‬

‫ ﺑﻪ ﺷﻤﺎ ﺍﻋﻼﻡ ﻣﻲ ﮔﺮﺩﺩ ﻛﻪ ﺑﻪ‬،‫ ﺩﻗﻴﻘﻪ ﻭ ﺛﺎﻧﻴﻪ‬،‫ ﭘﺲ ﺍﺯ ﺗﺎﻳﭗ ﺳﺎﻋﺖ‬: ‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ‬ .( ‫ ﺳﺎﻝ‬، ‫ ﻣﺎﻩ‬، ‫ﺍﻃﻼﻋﺎﺕ ﺑﻴﺸﺘﺮﻱ ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ ) ﺭﻭﺯ‬

360

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‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ ‪ :‬ﺑﺎ ﻓﺸﺮﺩﻥ ﻛﻠﻴﺪﻫﺎﻱ ‪ ctrl-P‬ﻭ ﻳﺎ )ﻛﻠﻴﺪ ‪ ( up arrow‬ﺩﺳﺘﻮﺭ‬

‫ﺗﺎﻳﭗ ﺷﺪﻩ ﻗﺒﻠﻲ ﺗﻜﺮﺍﺭ ﻭ ﺑﺎ ﺍﺿﺎﻓﻪ ﻧﻤﻮﺩﻥ ﻋﻼﻣﺖ ﺳﻮﺍﻝ ﺑﻪ ﺍﻧﺘﻬﺎﻱ ﺁﻥ ‪ ،‬ﻭﺿﻌﻴﺖ‬

‫ﺁﺭﮔﻮﻣﺎﻥ ﻫﺎﻱ ﺍﺿﺎﻓﻲ ﺁﻥ ﻣﺸﺨﺺ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ ‪:‬ﺑﺎ ﻣﺸﺎﻫﺪﻩ ﻋﻼﻣﺖ "^" ﻭ ﭘﺎﺳﺦ ﺳﻴﺴﺘﻢ ‪ ،‬ﺷﺎﻫﺪ ﺑﺮﻭﺯ ﻳﻚ ﺧﻄﺎﺀ‬

‫ﺧﻮﺍﻫﻴﻢ ﺑﻮﺩ ‪ .‬ﻣﺤﻞ ﻋﻼﻣﺖ "^" ‪ ،‬ﻣﻜﺎﻥ ﺍﺣﺘﻤﺎﻟﻲ ﺑﺮﻭﺯ ﺧﻄﺎﺀ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪ .‬ﺑﺮﺍﻱ‬ ‫ﺗﺎﻳﭗ ﺻﺤﻴﺢ ﺩﺳﺘﻮﺭ ‪ ،‬ﻣﺠﺪﺩﺍ" ﺩﺳﺘﻮﺭ ﺭﺍ ﺗﺎ ﻣﺤﻠﻲ ﻛﻪ ﻋﻼﻣﺖ "^" ﻣﺸﺨﺺ ﻧﻤﻮﺩﻩ‬

‫ﺗﺎﻳﭗ ﻛﺮﺩﻩ ﻭ ﺳﭙﺲ ﺍﺯ ﻋﻼﻣﺖ "?" ﺑﺮﺍﻱ ﺁﮔﺎﻫﻲ ﺍﺯ ﮔﺮﺍﻣﺮ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‬ ‫‪.‬‬

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‫ﻣﺮﺣﻠﻪ ﺷﺸﻢ ‪ :‬ﭘﺲ ﺍﺯ ﺩﺭﺝ ﺳﺎﻋﺖ ‪ ،‬ﺩﻗﻴﻘﻪ ﻭ ﺛﺎﻧﻴﻪ ﺑﺮ ﺍﺳﺎﺱ ﻓﺮﻣﺖ ﺩﺭﺧﻮﺍﺳﺘﻲ ‪ ،‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﺳﺎﻝ ﺭﺍ ﻧﻴﺰ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻓﺮﻣﺖ ﻣﻮﺭﺩ ﻧﻈﺮ ﻭﺍﺭﺩ ﻣﻲ ﻧﻤﺎﺋﻴﻢ ‪.‬‬ ‫ﺗﻨﻈﻴﻢ ﺯﻣﺎﻥ ﺭﻭﺗﺮ‬ ‫‪Router Con0 is now available‬‬ ‫‪Press RETURN to get started.‬‬ ‫‪Router>enable‬‬ ‫?‪Router#cl‬‬ ‫‪clear clock‬‬ ‫? ‪Router#clock‬‬ ‫‪set Set the time and date‬‬ ‫? ‪Router#clock set‬‬ ‫‪hh:mm:ss Current Time‬‬ ‫? ‪Router#clock set 13:22:00‬‬ ‫‪<1-31> Day of the month‬‬ ‫‪MONTH Month of the year‬‬ ‫? ‪Router#clock set 13:22:00 17 october‬‬ ‫‪<1999-2035> Year‬‬

‫‪Router#clock set 13:22:00 17 october 2005‬‬ ‫‪Router#‬‬

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‫ﺩﺳﺘﻮﺭﺍﺕ ﺍﺿﺎﻓﻲ ﻭﻳﺮﺍﻳﺶ‬ ‫ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ ﺷﺎﻣﻞ ﻳﻚ ‪ mode‬ﺍﺿﺎﻓﻲ ﻭﻳﺮﺍﻳﺶ ﺍﺳﺖ ﻛﻪ ﺑﺎ ﺗﻌﺮﻳﻒ ﻣﺠﻤﻮﻋﻪ‬

‫ﺍﻱ ﺍﺯ ﻛﻠﻴﺪﻫﺎ ‪ ،‬ﺍﻣﻜﺎﻥ ﻭﻳﺮﺍﻳﺶ ﻳﻚ ﺩﺳﺘﻮﺭ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻛﺎﺭﺑﺮ ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﺪ‪ mode .‬ﻓﻮﻕ ‪،‬‬ ‫ﺑﻪ ﺻﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﺗﻤﺎﻳﻞ ﻣﻲ ﺗﻮﺍﻥ ﺁﻥ ﺭﺍ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫ﺩﺳﺘﻮﺭ ‪ terminal no editing‬ﺩﺭ ‪ privileged EXEC mode‬ﻏﻴﺮﻓﻌﺎﻝ ﻧﻤﻮﺩ‪.‬‬

‫ﺩﺭ ﺍﻳﻦ ‪ ، mode‬ﺍﺯ ‪ Scrolling‬ﺍﻓﻘﻲ ﺩﺭ ﻣﻮﺍﺭﺩﻱ ﻛﻪ ﻃﻮﻝ ﻳﻚ ﺩﺳﺘﻮﺭ ﺍﺯ ﻳﻚ ﺧﻂ‬

‫ﺗﺠﺎﻭﺯ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻭ ﺯﻣﺎﻧﻲ ﻛﻪ ‪ cursor‬ﺑﻪ ﻣﻨﺘﻬﻲ ﺍﻟﻴﻪ‬ ‫ﺳﻤﺖ ﺭﺍﺳﺖ ﻣﻲ ﺭﺳﺪ ‪ ،‬ﺧﻂ ﺩﺳﺘﻮﺭ ﺑﻪ ﺍﻧﺪﺍﺯﻩ ﺩﻩ ﺣﺮﻑ ﺑﻪ ﺳﻤﺖ ﭼﭗ ﺷﻴﻔﺖ ﭘﻴﺪﺍ ﻧﻤﻮﺩﻩ ﻭ‬ ‫ﺍﻭﻟﻴﻦ ﺩﻩ ﺣﺮﻑ ﺗﺎﻳﭗ ﺷﺪﻩ ﻧﻤﺎﻳﺶ ﺩﺍﺩﻩ ﻧﺨﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﻭﺟﻮﺩ ﻋﻼﻣﺖ "‪ "$‬ﺩﺭ ﺍﺑﺘﺪﺍﻱ ﻳﻚ‬

‫ﺩﺳﺘﻮﺭ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺍﺳﺖ ﻛﻪ ﺧﻂ ﺑﻪ ﺳﻤﺖ ﭼﭗ ‪ scroll‬ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪.‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻮﺍﺑﻖ ﺩﺳﺘﻮﺭﺍﺕ ﺗﺎﻳﭗ ﺷﺪﻩ‬ ‫ﺑﺨﺶ ﺭﺍﺑﻂ ﻛﺎﺭﺑﺮ ﺭﻭﺗﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﻣﺠﺪﺩ ﺍﺯ ﺩﺳﺘﻮﺭﺍﺕ ﺗﺎﻳﭗ ﺷﺪﻩ ‪ ،‬ﺁﻧﺎﻥ ﺭﺍ ﺩﺭ‬ ‫ﻳﻚ ﺑﺎﻓﺮ ﻭ ﺑﺎ ﻇﺮﻓﻴﺖ ﻣﺤﺪﻭﺩ ﻧﮕﻬﺪﺍﺭﻱ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﺳﻮﺍﺑﻖ ﻭ ﻳﺎ ﺗﺎﺭﻳﺨﭽﻪ ﺩﺳﺘﻮﺭﺍﺕ (‪ .‬ﺑﺎ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﻣﻜﺎﻧﺎﺕ ﻣﻮﺟﻮﺩ ﻣﻲ ﺗﻮﺍﻥ ﻋﻤﻠﻴﺎﺕ ﺯﻳﺮ ﺭﺍ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﻮﺍﺑﻖ ﺩﺳﺘﻮﺭﺍﺕ ﺍﻧﺠﺎﻡ‬ ‫ﺩﺍﺩ‪:‬‬ ‫•‬

‫ﺗﻨﻈﻴﻢ ﻭ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺍﻧﺪﺍﺯﻩ ﺑﺎﻓﺮ ﺳﻮﺍﺑﻖ‬

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‫ﻓﺮﺍﺧﻮﺍﻧﻲ ﻣﺠﺪﺩ ﺩﺳﺘﻮﺭﺍﺕ‬

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‫ﻏﻴﺮﻓﻌﺎﻝ ﻧﻤﻮﺩﻥ ﻭﻳﮋﮔﻲ "ﺳﻮﺍﺑﻖ ﺩﺳﺘﻮﺭﺍﺕ "‬

‫ﺳﻮﺍﺑﻖ ﺩﺳﺘﻮﺭﺍﺕ ﺑﻪ ﺻﻮﺭﺕ ﭘﻴﺶ ﻓﺮﺽ ﻓﻌﺎﻝ ﻣﻲ ﮔﺮﺩﺩ ﻭ ﻗﺎﺩﺭ ﺑﻪ ﺫﺧﻴﺮﻩ ﺣﺪﺍﻛﺜﺮ ﺩﻩ ﺧﻂ‬

‫ﺩﺳﺘﻮﺭ ﺩﺭ ﺑﺎﻓﺮ ﻣﺮﺑﻮﻃﻪ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﺮﺍﻱ ﺗﻐﻴﻴﺮ ﺗﻌﺪﺍﺩ ﺩﺳﺘﻮﺭﺍﺗﻲ ﻛﻪ ﻣﻲ ﺗﻮﺍﻥ ﺁﻧﺎﻥ ﺭﺍ ﺩﺭ ﻟﻴﺴﺖ‬

‫ﺳﻮﺍﺑﻖ ﻧﮕﻬﺪﺍﺭﻱ ﻧﻤﻮﺩ‪ ،‬ﺍﺯ ﺩﺳﺘﻮﺭ ‪ terminal history size‬ﻭ ﻳﺎ ‪history size‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺣﺪﺍﻛﺜﺮ ‪ ٢٥٦‬ﺩﺳﺘﻮﺭ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﻟﻴﺴﺖ ﺳﻮﺍﺑﻖ ﻧﮕﻬﺪﺍﺭﻱ ﻧﻤﻮﺩ‪.‬‬

‫ﺑﺮﺍﻱ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺩﺳﺘﻮﺭﺍﺕ ﺗﺎﻳﭗ ﺷﺪﻩ ‪ ،‬ﺍﺯ ﻛﻠﻴﺪﻫﺎﻱ ‪ Ctrl-P‬ﻭ ﻳﺎ ﻛﻠﻴﺪ ‪arrow Up‬‬

‫) ﺣﺮﻛﺖ ﺑﻪ ﺳﻤﺖ ﺍﺑﺘﺪﺍﻱ ﻟﻴﺴﺖ ( ﻭ ﻛﻠﻴﺪﻫﺎﻱ ‪ Ctrl-N‬ﻭ ﻳﺎ ‪ ) down arrow‬ﺣﺮﻛﺖ‬ ‫ﺑﻪ ﺳﻤﺖ ﭘﺎﺋﻴﻦ ﻟﻴﺴﺖ ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻳﮑﻲ ﺍﺯ ﭼﻨﺪﻳﻦ ﺭﻭﺵ ﻣﻮﺟﻮﺩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﭼﻨﺪ‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻴﮑﺪﻳﮕﺮ ﻭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ‬ ‫ﺍﻃﻼﻋﺎﺕ ﺑﻴﻦ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺯ ﺍﻣﻮﺍﺝ ﺭﺍﺩﻳﻮﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﻣﺒﺎﻧﻲ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬

‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺍﺯ ﺍﻳﺪﻩ" ﺿﺮﻭﺭﺗﻲ ﺑﻪ ﮐﺎﺑﻞ ﻫﺎ ﻱ ﺟﺪﻳﺪ‬

‫ﻧﻤﻲ ﺑﺎﺷﺪ"‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ‪ ،‬ﺗﻤﺎﻡ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﻴﮕﻨﺎﻝ‬ ‫ﻫﺎﺋﻲ ﺭﺍﺩﻳﻮﺋﻲ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﻧﺘﺸﺎﺭ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﻳﮑﺪﻳﮕﺮ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ‬

‫ﺷﺒﮑﻪ ﻫﺎ ﺩﺍﺭﺍﻱ ﺳﺎﺧﺘﺎﺭﻱ ﺳﺎﺩﻩ ﺑﻮﺩﻩ ﻭ ﺑﺮﺍﺣﺘﻲ ﻣﻲ ﺗﻮﺍﻥ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺘﺼﻞ ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ‬ ‫ﺷﺒﮑﻪ ﻫﺎ ﺭﺍ ﻣﮑﺎﻥ ﻫﺎﻱ ﺩﻳﮕﺮ ﺍﺳﺘﻘﺮﺍﺭ ﻭ ﮐﻤﺎﮐﻦ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﺷﺒﮑﻪ ﺑﻬﺮﻩ ﻣﻨﺪ ﮔﺮﺩﻳﺪ ﻣﺜﻼ" ﺩﺭ‬

‫ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺭﺍ ﺩﺭ ﻳﮏ ﻓﻀﺎﻱ ﮐﻮﭼﮏ ﻧﻈﻴﺮ ﻳﮏ ﺳﺎﺧﺘﻤﺎﻥ ﺍﺩﺍﺭﻱ ﺍﻳﺠﺎﺩ‬ ‫ﮐﺮﺩﻩ ﺑﺎﺷﻴﻢ ﻭ ﺩﺍﺭﺍﻱ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ laptop‬ﺑﺎﺷﻴﻢ ﮐﻪ ﺍﺯ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻣﺨﺼﻮﺹ ﺑﺪﻭﻥ‬

‫ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺩﺭ ﻫﺮ ﻣﮑﺎﻧﻲ ﺍﺯ ﺍﺩﺍﺭﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﮐﻪ ﻣﺴﺘﻘﺮ ﺷﺪﻩ ﺑﺎﺷﻴﻢ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ‬

‫‪ Laptop‬ﻣﻲ ﺗﻮﺍﻥ ﺑﺴﺎﺩﮔﻲ ﺑﻪ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻭ ﺍﺯ ﺍﻣﮑﺎﻧﺎﺕ ﻣﺮﺑﻮﻃﻪ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺯ ﻧﻘﻈﻪ ﻧﻈﺮ ﻧﻮﻉ ﺧﺪﻣﺎﺕ ﻭﺳﺮﻭﻳﺲ ﺩﻫﻲ ﺑﻪ ﺩﻭ ﮔﺮﻭﻩ‪ :‬ﻧﻈﻴﺮ ﺑﻪ ﻧﻈﻴﺮ‬

‫ﻭ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ‪ /‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻧﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻧﻈﻴﺮ ﺑﻪ ﻧﻈﻴﺮ ﻫﺮ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﺩﺭ ﺩﻭ ﻧﻘﺶ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻭ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﺩﺭ ﻫﺮ‬ ‫ﻟﺤﻈﻪ ﺍﺳﺖ‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ‪ /‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺻﺮﻓﺎ"‬

‫ﻣﻲ ﺗﻮﺍﻧﺪ ﻳﮏ ﻧﻘﺶ ﺭﺍ ﺑﺎﺯﻱ ﻧﻤﺎﻳﺪ‪ ) .‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ ﻳﺎ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ(‪ .‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬

‫ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﮐﻪ ﺑﺼﻮﺭﺕ ﻧﻈﻴﺮ ﺑﻪ ﻧﻈﻴﺮ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﮔﺮﺩﻧﻨﺪ‪ ،‬ﻫﺮ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺗﺒﺎﻁ‬

‫ﻣﺴﺘﻘﻴﻢ ﺑﺎ ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪ .‬ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ‬ ‫ﮐﺎﺑﻞ ﺑﺼﻮﺭﺕ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ‪ /‬ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﻩ‪ ،‬ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ‬ ‫ﺩﺍﺭﺍﻱ ﻳﮏ ‪ Access point‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪364‬‬

‫ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﻳﮏ ﮐﻨﺘﺮﻝ ﮐﻨﻨﺪﻩ ﮐﺎﺑﻠﻲ ﺑﻮﺩﻩ ﻭ ﻗﺎﺩﺭ ﺑﻪ ﺩﺭﻳﺎﻓﺖ ﻭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻪ‬

‫ﺁﺩﺍﭘﺘﻮﺭﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ )ﮐﺎﺭﺕ ﻫﺎﻱ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ( ﻧﺼﺐ ﺷﺪﻩ ﺩﺭ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﭼﻬﺎﺭ ﻧﻮﻉ ﻣﺘﻔﺎﻭﺕ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻭﺟﻮﺩ ﺩﺍﺭﺩ )ﺍﺯ ﮐﻨﺪ ﻭ ﺍﺭﺯﺍﻥ ﺗﺎ ﺳﺮﻳﻊ ﻭﮔﺮﺍﻥ (‬ ‫•‬ ‫•‬ ‫•‬ ‫•‬

‫‪BlueTooth‬‬ ‫‪IrDA‬‬ ‫‪(SWAP(HomeRF‬‬ ‫‪(Wi-Fi(WECA‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ Bluetooth‬ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﻋﻤﻮﻣﻴﺖ ﻧﺪﺍﺷﺘﻪ ﻭ ﺑﻨﻈﺮ ﻗﺎﺩﺭ ﺑﻪ ﭘﺎﺳﺨﮕﻮﺋﻲ ﺑﻪ‬ ‫ﮐﺎﺭﺑﺮﺍﻥ ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎ ﻱ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﻧﻤﻲ ﺑﺎﺷﻨﺪ‪Infrared Data(IrDA .‬‬

‫‪ (Association‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻱ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﺍﺯ ﺳﻴﮕﻨﺎﻝ ﻫﺎ ﻱ‬ ‫ﻧﻮﺭﻱ ﻣﺎﺩﻭﻥ ﻗﺮﻣﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻓﻮﻕ ﻧﺤﻮﻩ ﻋﻤﻠﻴﺎﺕ ﮐﻨﺘﺮﻝ ﺍﺯ ﺭﺍﻩ ﺩﻭﺭ‪،‬‬ ‫) ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ ﻳﮏ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ ﺧﺎﺹ( ﻭ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﺭﺍﻩ ﺩﻭﺭ )ﺗﻮﻟﻴﺪ ﺷﺪﻩ ﺗﻮﺳﻂ‬

‫ﺗﻮﻟﻴـﺪ ﮐﻨﻨﺪﻩ ﺩﻳﮕﺮ( ﺭﺍ ﺗﺒﻴــﻦ ﻣﻲ ﮐﻨـــﺪ‪ .‬ﺩﺳﺘــﮕﺎﻫﻬﺎﻱ ‪ IrDA‬ﺍﺯ ﻧﻮﺭﻣﺎﺩﻭﻥ ﻗﺮﻣﺰ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻗﺒﻞ ﺍﺯ ﺑﺮﺭﺳﻲ ﻣﺪﻝ ﻫﺎﻱ ‪ SWAP‬ﻭ ‪ Wi-Fi‬ﻻﺯﻡ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﺍﺑﺘﺪﺍ ﺑﺎ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﻭﻟﻴﻪ ﺍﻱ‬

‫ﮐﻪ ﺩﻭ ﻣﺪ ﻝ ﻓﻮﻕ ﺑﺮ ﺍﺳﺎﺱ ﺁﻧﻬﺎ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﻧﺪ ‪ ،‬ﺑﻴﺸﺘﺮ ﺁﺷﻨﺎ ﺷﻮﻳﻢ‪ .‬ﺍﻭﻟﻴﻦ ﻣﺸﺨﺼﺎﺕ ﺷﺒﮑﻪ‬

‫ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺑﺪﻭ ﻥ ﮐﺎﺑﻞ ﺑﺎ ﻧﺎﻡ ‪ IEEE 802.11‬ﺗﻮﺳﻂ ﻣﻮﺳﺴﻪ ‪ IEEE‬ﻋﺮﺿﻪ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻓﻮﻕ ﺩﻭ ﺭﻭﺵ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻫﻬﺎ ﺑﺎ ﺳﺮﻋﺖ ﺩﻭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫ﻣﻄﺮﺡ ﺷﺪ‪ .‬ﺩﻭ ﺭﻭﺵ ﻓﻮﻕ ﺑﺸﺮﺡ ﺯﻳﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪:‬‬ ‫•‬

‫‪(spectrum Direct-sequence spread(DSSS‬‬

‫•‬

‫‪(spectrum Frequency-hopping spread(FHSS‬‬

‫ﺩﻭ ﺭﻭﺵ ﻓﻮﻕ ﺍﺯ ﺗﮑﻨﻮﻟﻮﮊﻱ ‪ (Frequency-shift keying(FSK‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﻫﻤﭽﻨﻴﻦ ﺩﻭ ﺭﻭﺵ ﻓﻮﻕ ﺍﺯ ﺍﻣﻮﺍﺝ ﺭﺍﺩﻳﻮﺋﻲ ‪ Spread-spectrum‬ﺩﺭ ﻣﺤﺪﻭﺩﻩ ‪٢ /٤‬‬ ‫ﮔﻴﮕﺎﻫﺮﺗﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫‪365‬‬

‫‪ ، Spread Spectrum‬ﺑﺪﻳﻦ ﻣﻌﻨﻲ ﺍﺳﺖ ﮐﻪ ﺩﺍﺩﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺮﺍﻱ ﺍﺭﺳﺎﻝ ﺑﻪ ﺑﺨﺶ ﻫﺎﻱ‬ ‫ﮐﻮﭼﮑﺘﺮ ﺗﻘﺴﻴﻢ ﻭ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﻧﻬﺎ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﮐﺎﻧﺲ ﻫﺎﻱ ﮔﺴﺴﺘﻪ ﻗﺎﺑﻞ ﺩﺳﺘﻴﺎﺑﻲ ﺩﺭ ﻫﺮ‬

‫ﺯﻣﺎﻥ ‪ ،‬ﺍﺭﺳﺎﻝ ﺧﻮﺍﻫﻨﺪ ﺷﺪ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ ﮐﻪ ﺍﺯ ‪ DSSS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻫﺮ ﺑﺎﻳﺖ ﺩﺍﺩﻩ‬ ‫ﺭﺍ ﺑﻪ ﭼﻨﺪﻳﻦ ﺑﺨﺶ ﻣﺠﺰﺍ ﺗﻘﺴﻴﻢ ﻭ ﺁﻧﻬﺎ ﺭﺍ ﺑﺼﻮﺭﺕ ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻓﺮﮐﺎﻧﺲ ﻫﺎﻱ‬

‫ﻣﺘﻔﺎﻭﺕ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﻧﺪ‪.‬‬

‫‪ DSSS‬ﺍﺯ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺴﻴﺎﺭ ﺑﺎﻻﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ) ﺗﻘﺮﻳﺒﺎ" ‪ ٢٢‬ﻣﮕﺎﻫﺮﺗﺰ( ﺩﺳﺘﮕﺎﻫﻬﺎﺋﻲ‬ ‫ﮐﻪ ﺍﺯ ‪ FHSS‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺩﺭﻳﮏ ﺯﻣﺎﻥ ﭘﻴﻮﺳﺘﻪ ﮐﻮﺗﺎﻩ ‪ ،‬ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﮐﺮﺩﻩ ﻭ‬

‫ﺑﺎ ﺷﻴﻔﺖ ﺩﺍﺩﻥ ﻓﺮﮐﺎﻧﺲ )‪ (hop‬ﺑﺨﺶ ﺩﻳﮕﺮﻱ ﺍﺯ ﺍﻃﻼﻋﺎﺕ ﺭﺍ ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﺎ ﺗﻮﺟﻪ‬ ‫ﺑﻪ ﺍﻳﻨﮑﻪ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ‪ FHSS‬ﮐﻪ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺮﺗﺒﻂ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺑﺮ ﺍﺳﺎﺱ‬ ‫ﻓﺮﮐﺎﻧﺲ ﻣﺮﺑﻮﻃﻪ ﺍﻱ ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ‪ Hop‬ﻧﻤﺎﻳﻨﺪ ﻭ ﺍﺯ ﻫﺮ ﻓﺮﮐﺎﻧﺲ ﺩﺭ ﻳﮏ ﺑﺎﺯﻩ ﺯﻣﺎﻧﻲ‬ ‫ﺑﺴﻴﺎﺭ ﮐﻮﺗﺎﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ)ﺣﺪﻭﺩﺍ" ‪٤٠٠‬ﻣﻴﻠﻲ ﺛﺎﻧﻴﻪ(‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﭼﻨﺪﻳﻦ‬ ‫ﺷﺒﮑﻪ‪ FHSS‬ﺩﺭ ﻳﮏ ﻣﺤﻴﻂ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ)ﺑﺪﻭﻥ ﺍﺛﺮﺍﺕ ﺟﺎﻧﺒﻲ(‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ‪ FHSS‬ﺻﺮﻓﺎ"‬ ‫ﺩﺍﺭﺍﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻳﮏ ﻣﮕﺎﻫﺮﺗﺰ ﻭ ﻳﺎ ﮐﻤﺘﺮ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪ HomeRF‬ﻭ ‪SWAP‬‬ ‫‪ ، HomeRF‬ﺍﺗﺤﺎﺩﻳﻪ ﺍﻱ ﺍﺳﺖ ﮐﻪ ﺍﺳﺘﺎﻧﺪﺍﺭﻱ ﺑﺎ ﻧﺎﻡ ‪Shared Wireless (SWAP‬‬

‫‪ (Access protocol‬ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ SWAP .‬ﺩﺍﺭﺍﻱ ﺷﺶ ﮐﺎﻧﺎﻝ ﺻﻮﺗﻲ ﻣﺘﻔﺎﻭﺕ‬ ‫ﺑﺮ ﺍﺳﺎﺱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ DECT‬ﻭ ‪ ٨٠٢,١١‬ﺍﺳﺖ‪ .‬ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ‪ SWAP‬ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ‪hop ٥٠‬‬ ‫ﺍﻳﺠﺎﺩ ﻭ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻳﮏ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺑﺮﺧﻲ ﺍﺯ ﻣﺪﻝ ﻫﺎ‬ ‫ﻣﻴﺰﺍﻥ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺗﺎ ﺩﻭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻫﻢ ﻣﻲ ﺭﺳﺪ‪ ، .‬ﺗﻮﺍﻧﺎﺋﻲ ﻓﻮﻕ ﺍﺭﺗﺒﺎﻁ ﻣﺴﺘﻘﻴﻢ‬ ‫ﺑﻪ ﺗﻌﺪﺍﺩ ﺍﻳﻨﺘﺮﻓﻴﺲ ﻫﺎﻱ ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﺠﻴﻂ ﻋﻤﻠﻴﺎﺗﻲ ﺩﺍﺭﺩ‪ .‬ﻣﺰﺍﻳﺎﻱ ‪ SWAP‬ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬ ‫•‬

‫ﻗﻴﻤﺖ ﻣﻨﺎﺳﺐ‬

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‫ﻧﺼﺐ ﺁﺳﺎﻥ‬

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‫ﺑﻪ ﮐﺎﺑﻞ ﻫﺎﻱ ﺍﺿﺎﻓﻪ ﻧﻴﺎﺯ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‬ ‫‪366‬‬

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‫ﺩﺍﺭﺍﻱ ‪ Access point‬ﻧﻴﺴﺖ‬

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‫ﺩﺍﺭﺍﻱ ﺷﺶ ﮐﺎﻧﺎﻝ ﺻﻮﺗﻲ ﺩﻭ ﻃﺮﻓﻪ ﻭ ﻳﮏ ﮐﺎﻧﺎﻝ ﺩﺍﺩﻩ ﺍﺳﺖ‬

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‫ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ ١٢٧‬ﺩﺳﺘﮕﺎﻩ ﺩﺭ ﻫﺮ ﺷﺒﮑﻪ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬

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‫ﺍﻣﮑﺎﻥ ﺩﺍﺷﺘﻦ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﺩﺭ ﻳﮏ ﻣﺤﻞ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺍﻣﮑﺎﻥ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﻤﻦ ﺳﺎﺯﻱ ﺩﺍﺩﻩ ﻫﺎ ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪.‬‬

‫ﺑﺮﺧﻲ ﺍﺯ ﺍﺷﮑﺎﻻﺕ ‪ SWAP‬ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬ ‫•‬

‫ﺩﺍﺭﺍﻱ ﺳﺮﻋﺖ ﺑﺎﻻ ﻧﻴﺴﺖ )ﺩﺭ ﺣﺎﻟﺖ ﻋﺎﺩﻱ ﻳﮏ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ(‬

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‫ﺩﺍﺭﺍﻱ ﺩﺍﻣﻨﻪ ﻣﺤﺪﻭﺩﻱ ﺍﺳﺖ )‪ ٧٥‬ﺗﺎ ‪ ١٢٥‬ﻓﻮﺕ ‪ ٢٣ /‬ﺗﺎ ‪ ٣٨‬ﻣﺘﺮ(‬

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‫ﺑﺎ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ‪ FHSS‬ﺳﺎﺯﮔﺎﺭ ﻧﻴﺴﺖ‪.‬‬

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‫ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺩﺍﺭﺍﻱ ﻓﻠﺰ ﻭ ﻳﺎ ﻭﺟﻮﺩ ﺩﻳﻮﺍﺭ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺍﻓﺖ ﺍﺭﺗﺒﺎﻃﺎﺕ ﺷﻮﺩ‪.‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﺑﻠﻲ ﻣﺸﮑﻞ ﺍﺳﺖ‪.‬‬

‫ﺗﺮﺍﺗﺴﻴﻮﺭ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻭﺍﻗﻌﻲ ﺑﻬﻤﺮﺍﻩ ﻳﮏ ﺁﻧﺘﻦ ﮐﻮﭼﮏ ﺩﺭ ﻳﮏ ﮐﺎﺭﺕ ‪ PCI , ISA‬ﻭ ﻳﺎ‬ ‫‪ PCMCIA‬ﺍﻳﺠﺎﺩ) ﺳﺎﺧﺘﻪ ( ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ Laptop‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ ،‬ﮐﺎﺭﺕ ‪ PCMCIA‬ﺑﺼﻮﺭﺕ ﻣﺴﺘﻘﻴﻢ ﺑﻪ ﻳﮑﻲ ﺍﺯ ﺍﺳﻼﺕ ﻫﺎﻱ ‪ PCMCIA‬ﻣﺘﺼﻞ‬

‫ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺩﺭ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺷﺨﺼﻲ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮏ ﮐﺎﺭﺕ ﺍﺧﺘﺼﺎﺻﻲ ‪ ، ISA‬ﮐﺎﺭﺕ‬

‫‪ HomeRF PCI‬ﻭ ﻳﺎ ﻳﮏ ﮐﺎﺭﺕ ‪ PCMCIA‬ﺑﻬﻤﺮﺍﻩ ﻳﮏ ﺁﺩﺍﭘﺘﻮﺭ ﻣﺨﺼﻮﺹ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﮐﺮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺿﺮﻭﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺭﺕ ﻫﺎﻱ ﺍﺧﺘﺼﺎﺻﻲ‪ ،‬ﺻﺮﻓﺎ" ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ‬

‫ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ‪ SWAP‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﭼﺎﭘﮕﺮﻫﺎ ﻭ ﺳﺎﻳﺮ ﻭﺳﺎﺋﻞ ﺟﺎﻧﺒﻲ ﻣﻲ ﺑﺎﻳﺴﺖ ﻣﺴﺘﻘﻴﻤﺎ"‬

‫ﺑﻪ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺘﺼﻞ ﻭ ﺗﻮﺳﻂ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﻣﻨﺒﻊ ﺍﺷﺘﺮﺍﮐﻲ ﻣﻮﺭﺩ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻗﺮﺍﺭ ﮔﻴﺮﻧﺪ‪.‬‬ ‫ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ SWAP‬ﺑﺼﻮﺭﺕ "ﻧﻈﻴﺮ ﺑﻪ ﻧﻈﻴﺮ" ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﺍﺧﻴﺮﺍ"‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻓﺰﺍﻳﺶ ﺩﺍﻣﻨﻪ ﺗﺎﺛﻴﺮ ﭘﺬﻳﺮﻱ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ Access point ،‬ﻫﺎﺋﻲ ﺭﺍ‬ ‫ﺑﻪ ﺑﺎﺯﺍﺭ ﻋﺮﺿﻪ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ‪ HomeRf‬ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﻳﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪،‬‬ ‫ﺩﺍﺭﺍﻱ ﻗﻴﻤﺖ ﻣﻨﺎﺳﺐ ﺗﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪367‬‬

‫‪ WECA‬ﻭ ‪Wi-Fi‬‬

‫‪ (Alliance Wireless Ethernet Compatibility(WECA‬ﺭﻭﻳﮑﺮﺩ ﺟﺪﻳﺪﻱ ﺭﺍ‬ ‫ﻧﺴﺒﺖ ﺑﻪ ‪ HomeRF‬ﺍﺭﺍﺋﻪ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ ، Wi-Fi .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻱ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﺗﻤﺎﻡ‬ ‫ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﺑﺮﺍﻱ ﺗﻮﻟﻴﺪ ﻣﺤﺼﻮﻻﺕ ﻣﺒﺘﻲ ﺑﺮ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ ٨٠٢,١١ IEEE‬ﺗﺎﮐﻴﺪ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻣﺸﺨﺼﺎﺕ ﻓﻮﻕ ‪ FHSS‬ﺭﺍ ﺣﺬﻑ ﻭ ﺗﺎﮐﻴﺪ ﺑﺮ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ‪ DSSS‬ﺩﺍﺭﺩ‪ ) .‬ﺑﺪﻟﻴﻞ ﻇﺮﻓﻴﺖ ﺑﺎﻻ‬ ‫ﺩﺭ ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ (‪ .‬ﺑﺮ ﺍﺳﺎﺱ ‪ ، IEEE 802.11b‬ﻫﺮ ﺩﺳﺘﮕﺎﻩ ﻗﺎﺩﺭ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ‬

‫ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﺳﺮﻋﺖ ﻳﺎﺯﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺳﺮﻋﺖ ﻓﻮﻕ ﭘﺎﺳﺨﮕﻮ ﻧﺒﺎﺷﺪ‬

‫‪ ،‬ﺑﺘﺪﺭﻳﺞ ﺳﺮﻋﺖ ﺑﻪ ‪ ٥/٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‪ ،‬ﺩﻭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻭ ﻧﻬﺎﻳﺘﺎ" ﺑﻪ ﻳﮏ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬ ‫ﺛﺎﻧﻴﻪ ﺗﻨﺰﻝ ﭘﻴﺪﺍ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺷﺒﮑﻪ ﺍﺯ ﺻﻼﺑﺖ ﻭ ﺍﻋﺘﻤﺎﺩ ﺑﻴﺸﺘﺮﻱ ﺑﺮﺧﻮﺭﺩﺍﺭ‬ ‫ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﻣﺰﺍﻳﺎﻱ ‪ Wi-Fi‬ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ ‪:‬‬ ‫•‬

‫ﺳﺮﻋﺖ ﺑﺎﻻ )ﻳﺎﺯﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ(‬

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‫ﻗﺎﺑﻞ ﺍﻋﺘﻤﺎﺩ‬

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‫ﺩﺍﺭﺍﻱ ﺩﺍﻣﻨﻪ ﺑﺎﻻﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ )‪ ١,٠٠٠‬ﻓﻮﺕ ﻳﺎ ‪ ٣٠٥‬ﻣﺘﺮ ﺩﺭ ﻗﻀﺎﻱ ﺑﺎﺯ ﻭ ‪ ٢٥٠‬ﺗﺎ ‪٤٠٠‬‬ ‫ﻓﻮﺕ ‪ ٧٦ /‬ﺗﺎ ‪ ١٢٢‬ﻣﺘﺮ ﺩﺭ ﻓﻀﺎﻱ ﺑﺴﺘﻪ(‬

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‫ﺑﺎ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﺑﻠﻲ ﺑﺴﺎﺩﮔﻲ ﺗﺮﮐﻴﺐ ﻣﻲ ﮔﺮﺩ‪.‬‬

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‫ﺑﺎ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ‪ ) DSSS 802.11‬ﺍﻭﻟﻴﻪ ( ﺳﺎﺯﮔﺎﺭ ﺍﺳﺖ‪.‬‬

‫ﺑﺮﺧﻲ ﺍﺯ ﺍﺷﮑﺎﻻﺕ ‪ Wi-Fi‬ﻋﺒﺎﺭﺗﻨﺪ ﺍﺯ‪:‬‬ ‫•‬

‫ﮔﺮﺍﻥ ﻗﻴﻤﺖ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﻭ ﺗﻨﻈﻴﻤﺎﺕ ﺁﻥ ﻣﺸﮑﻞ ﺍﺳﺖ‪.‬‬

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‫ﻧﻮﺳﺎﻧﺎﺕ ﺳﺮﻋﺖ ﺯﻳﺎﺩ ﺍﺳﺖ‪.‬‬

‫‪ Wi-Fi‬ﺳﺮﻋﺖ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﺭﺍ ﺑﺪﻭﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﻗﺮﺍﺭ ﻣﻲ ﺩﻫﺪ‪ .‬ﮐﺎﺭﺕ‬ ‫ﻫﺎﻱ ﺳﺎﺯﮔﺎﺭ ﺑﺎ ‪ Wi-Fi‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ " ﻧﻈﻴﺮ ﺑﻪ ﻧﻈﻴﺮ " ﻭﺟﻮﺩ ﺩﺍﺭﺩ‪ ،‬ﻭﻟﻲ‬

‫ﻣﻌﻤﻮﻻ" ‪ Wi-Fi‬ﺑﻪ ‪ Access Point‬ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺍﻏﻠﺐ ‪ Access point‬ﻫﺎ‬ ‫‪368‬‬

‫ﺩﺍﺭﺍﻱ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﺑﻠﻲ ﺍﺗﺮﻧﺖ ﻧﻴﺰ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺍﮐﺜﺮ‬

‫ﺗﺮﺍﻧﺴﻴﻮﺭﻫﺎﻱ ‪ Wi-Fi‬ﺑﺼﻮﺭﺕ ﮐﺎﺭﺕ ﻫﺎﻱ ‪ PCMCIA‬ﻋﺮﺿﻪ ﺷﺪﻩ ﺍﻧﺪ‪ .‬ﺑﺮﺧﻲ ﺍﺯ‬ ‫ﺗﻮﻟﻴﺪﮐﻨﻨﺪﮔﺎﻥ ﮐﺎﺭﺕ ﻫﺎﻱ ‪ PCI‬ﻭ ﻳﺎ ‪ ISA‬ﺭﺍ ﻧﻴﺰ ﻋﺮﺿﻪ ﻧﻤﻮﺩﻩ ﺍﻧﺪ‪.‬‬

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‫ﺍﻧﻮﺍﻉ ﺷﺒﮑﻪ ﻫﺎﻱ ‪Wireless‬‬ ‫ﺍﻣﺮﻭﺯﻩ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ) ‪ ( Wireless‬ﺩﺭ ﺍﺑﻌﺎﺩ ﻣﺘﻔﺎﻭﺕ ﻭ ﺑﺎ ﺍﻫﺪﺍﻑ‬ ‫ﻣﺨﺘﻠﻒ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺮﻗﺮﺍﺭﻱ ﻳﮏ ﺗﻤﺎﺱ ﺍﺯ ﻃﺮﻳﻖ ﺩﺳﺘﮕﺎﻩ ﻣﻮﺑﺎﻳﻞ‪ ،‬ﺩﺭﻳﺎﻓﺖ ﻳﮏ ﭘﻴﺎﻡ‬ ‫ﺑﺮ ﺭﻭﻱ ﺩﺳﺘﮕﺎﻩ ‪ pager‬ﻭ ﺩﺭﻳﺎﻓﺖ ﻧﺎﻣﻪ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻭﻧﻴﮑﻲ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ‪،PDA‬‬

‫ﻧﻤﻮﻧﻪ ﻫﺎﺋﻲ ﺍﺯ ﮐﺎﺭﺑﺮﺩ ﺍﻳﻦ ﻧﻮﻉ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺗﻤﺎﻣﻲ ﻣﻮﺍﺭﺩ ﻓﻮﻕ‪ ،‬ﺩﺍﺩﻩ ﻭ ﻳﺎ‬ ‫ﺻﻮﺕ ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﺩ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﻳﮏ ﮐﺎﺭﺑﺮ‪ ،‬ﺑﺮﻧﺎﻣﻪ ﻭ ﻳﺎ ﺳﺎﺯﻣﺎﻥ ﺗﻤﺎﻳﻞ ﺑﻪ ﺍﻳﺠﺎﺩ ﭘﺘﺎﺳﻴﻞ ﻗﺎﺑﻠﻴـﺖ ﺣﻤﻞ ﺩﺍﺩﻩ ﺭﺍ‬ ‫ﺩﺍﺷﺘﻪ ﺑﺎﺷﺪ‪ ،‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﺎﻳﺪ‪ .‬ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬

‫ﻋﻼﻭﻩ ﺑﺮ ﺻﺮﻓﻪ ﺟﻮﺋﻲ ﺩﺭ ﺯﻣﺎﻥ ﻭ ﻫﺰﻳﻨﻪ ﮐﺎﺑﻞ ﮐﺸﻲ‪ ،‬ﺍﻣﮑﺎﻥ ﺑﺮﻭﺯ ﻣﺴﺎﺋﻞ ﻣﺮﺗﺒﻂ ﺑﺎ ﻳﮏ‬ ‫ﺷﺒﮑﻪ ﮐﺎﺑﻠﻲ ﺭﺍ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻣﻲ ﺗﻮﺍﻥ ﺩﺭ ﻣﮑﺎﻥ ﻋﻤﻮﻣﻲ‪ ،‬ﮐﺘﺎﺑﺨﺎﻧﻪ ﻫﺎ‪ ،‬ﻫﺘﻞ ﻫﺎ‪ ،‬ﺭﺳﺘﻮﺭﺍﻥ ﻫﺎ ﻭ‬

‫ﻣﺪﺍﺭﺱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺩﺭ ﺗﻤﺎﻣﻲ ﻣﮑﺎﻥ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ‬ ‫ﻧﻴﺰ ﻓﺮﺍﻫﻢ ﻧﻤﻮﺩ‪ .‬ﻳﮑﻲ ﺍﺯ ﭼﺎﻟﺶ ﻫﺎﻱ ﺍﺻﻠﻲ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﺑﻪ ﮐﻴﻔﻴﺖ ﺳﺮﻭﻳﺲ‬ ‫)‪ ( QoS‬ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺑﺮﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺑﻪ ﻫﺮ ﺩﻟﻴﻠﻲ ﺑﺮ ﺭﻭﻱ ﺧﻂ ﭘﺎﺭﺍﺯﻳﺖ ﺍﻳﺠﺎﺩ‬

‫ﮔﺮﺩﺩ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺍﺭﺗﺒﺎﻁ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﻗﻄﻊ ﻭ ﻳﺎ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻄﻠﻮﺏ ﺍﺯ ﺁﻥ ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ‬

‫ﺑﺎﺷﺪ‪.‬‬ ‫ﺍﻧﻮﺍﻉ ﺷﺒﮑﻪ ﻫﺎﻱ ‪wireless‬‬ ‫•‬

‫‪ . Wireless Local Area Networks :WLANS‬ﺷﺒﮑﻪ ﻫﺎﻱ‬

‫ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﮐﺎﺭﺑﺮﺍﻥ ﺳﺎﮐﻦ ﺩﺭ ﻳﮏ ﻣﻨﻄﻘﻪ ﻣﺤﺪﻭﺩ ﻧﻈﻴﺮ ﻣﺤﻮﻃﻪ ﻳﮏ ﺩﺍﻧﺸﮕﺎﻩ‬ ‫ﻭ ﻳﺎ ﮐﺘﺎﺑﺨﺎﻧﻪ ﺭﺍ ﺑﻪ ﺷﺒﮑﻪ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫‪ . Wireless Personal Area Networks :WPANS‬ﺩﺭ ﺷﺒﮑﻪ‬

‫ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺩﺳﺘﮕﺎﻫﻬﺎﻱ ﺷﺨﺼﻲ )ﻧﻈﻴﺮ ‪ ( laptop‬ﺩﺭ ﻳﮏ ﻧﺎﺣﻴﻪ‬ ‫ﻣﺤﺪﻭﺩ )ﺣﺪﻭﺩ ‪ ٩١٤‬ﺳﺎﻧﺘﻲ ﻣﺘﺮ( ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺍﺯ ﺩﻭ‬ ‫ﺗﮑﻨﻮﻟﻮﮊﻱ ﻣﺘﺪﺍﻭﻝ ‪ ( IR ) Infra Red‬ﻭ ) ‪، IEEE 802.15 ) Bluetooth‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫‪ . Wireless Metropolitan Area Networks :WMANS‬ﺩﺭ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﺩﺭ ﻳﮏ ﺷﻬﺮ ﺑﺰﺭﮒ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﺍﻏﻠﺐ ﺑﻪ ﻋﻨﻮﺍﻥ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ backup‬ﮐﺎﺑﻠﻲ )ﻣﺴﻲ‬ ‫‪،‬ﻓﻴﺒﺮ ﻧﻮﺭﻱ( ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫‪ . Wireless Wide Area Networks :WWANS‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺷﻬﺮﻫﺎ ﻭ ﻳﺎ ﺣﺘﻲ ﮐﺸﻮﺭﻫﺎ ﻭ ﺍﺯ ﻃﺮﻳﻖ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺎﻫﻮﺍﺭﻩ‬ ‫ﺍﻱ ﻣﺘﻔﺎﻭﺕ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ﻓﻮﻕ ﺑﻪ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ‪ ) G٢‬ﻧﺴﻞ ﺩﻭﻡ(‬

‫ﻣﻌﺮﻭﻑ ﺷﺪﻩ ﺍﻧﺪ‪.‬‬ ‫ﺍﻣﻨﻴﺖ‬

‫ﺑﺮﺍﻱ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺍﻣﻨﻴـﺖ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺍﺯ ﺳﻪ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪:‬‬ ‫•‬

‫‪ . Wired Equivalent Privacy : WEP‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ‪ ،‬ﻫﺪﻑ‬

‫ﺗﻮﻗﻒ ﺭﻩ ﮔﻴﺮﻱ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻓﺮﮐﺎﻧﺲ ﺭﺍﺩﻳﻮﺋﻲ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﻏﻴﺮ ﻣﺠﺎﺯ ﺑﻮﺩﻩ ﻭ‬ ‫ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﻮﭼﮏ ﻣﻨﺎﺳﺐ ﺍﺳﺖ‪ .‬ﻋﻠﺖ ﺍﻳﻦ ﺍﻣﺮ ﺑﻪ ﻋﺪﻡ ﻭﺟﻮﺩ ﭘﺮﻭﺗﮑﻞ ﺧﺎﺻﻲ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺪﻳﺮﻳﺖ "ﮐﻠﻴﺪ " ﺑﺮ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻫﺮ "ﮐﻠﻴﺪ " ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﻪ ﺻﻮﺭﺕ ﺩﺳﺘﻲ‬

‫ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﺗﻌﺮﻳﻒ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻬﻲ ﺍﺳﺖ ﺩﺭ ﺻﻮﺭﺕ ﺑﺰﺭﮒ ﺑﻮﺩﻥ ﺷﺒﮑﻪ‪،‬‬ ‫ﻓﺮﺁﻳﻨﺪ ﻓﻮﻕ ﺍﺯ ﺟﻤﻠﻪ ﻋﻤﻠﻴﺎﺕ ﻭﻗﺖ ﮔﻴﺮ ﺑﺮﺍﻱ ﻫﺮ ﻣﺪﻳﺮ ﺷﺒﮑﻪ ﺧﻮﺍﻫﺪ ﺑﻮﺩ‪،WEP .‬‬ ‫ﻣﺒﺘﻨﻲ ﺑﺮ ﺍﻟﮕﻮﺭﻳﺘﻢ ﺭﻣﺰﻧﮕﺎﺭﻱ ‪ RC4‬ﺍﺳﺖ ﮐﻪ ﺗﻮﺳﻂ ‪ RSA Data System‬ﺍﺭﺍﺋﻪ‬

‫ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺗﻤﺎﻣﻲ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﮔﺎﻥ ﻭ ‪ Point Aceess‬ﻫﺎ ﺑﮕﻮﻧﻪ ﺍﻱ‬

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‫ﭘﻴﮑﺮﺑﻨﺪﻱ ﻣﻲ ﮔﺮﺩﻧﺪ ﮐﻪ ﺍﺯ ﻳﮏ ﮐﻠﻴﺪ ﻣﺸﺎﺑﻪ ﺑﺮﺍﻱ ﺭﻣﺰﻧﮕﺎﺭﻱ ﻭ ﺭﻣﺰﮔﺸﺎﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫•‬

‫‪ .Service Set Identifier :SSID‬ﺭﻭﺵ ﻓﻮﻕ ﺑﻪ ﻣﻨﺰﻟﻪ ﻳﮏ "ﺭﻣﺰﻋﺒﻮﺭ"‬

‫ﺑﻮﺩﻩ ﮐﻪ ﺍﻣﮑﺎﻥ ﺗﻘﺴﻴﻢ ﻳﮏ ﺷﺒﮑﻪ ‪ WLAN‬ﺑﻪ ﭼﻨﺪﻳﻦ ﺷﺒﮑﻪ ﻣﺘﻔﺎﻭﺕ ﺩﻳﮕﺮ ﮐﻪ ﻫﺮ‬ ‫ﻳﮏ ﺩﺍﺭﺍﻱ ﻳﮏ ﺷﻨﺎﺳﻪ ﻣﻨﺤﺼﺮ ﺑﻔﺮﺩ ﻣﻲ ﺑﺎﺷﻨﺪ ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﺷﻨﺎﺳﻪ ﻫﺎﻱ‬ ‫ﻓﻮﻕ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺮﺍﻱ ﻫﺮ ‪ access point‬ﺗﻌﺮﻳﻒ ﮔﺮﺩﻧﺪ‪ .‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺳﺮﻭﻳﺲ‬

‫ﮔﻴﺮﻧﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻫﺮ ﺷﺒﮑﻪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﮕﻮﻧﻪ ﺍﻱ ﭘﮑﺮﺑﻨﺪﻱ ﮔﺮﺩﺩ ﮐﻪ‬ ‫ﺩﺍﺭﺍﻱ ﺷﻨﺎﺳﻪ ‪ SSID‬ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺷﻨﺎﺳﻪ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﺎ ﺷﻨﺎﺳﻪ ﺷﺒﮑﻪ ﻣﻮﺭﺩ ﻧﻈﺮ ﻣﻄﺎﺑﻘﺖ ﻧﻤﺎﻳﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ‬ ‫ﺑﻪ ﺷﺒﮑﻪ ﺑﺮﺍﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﻓﻴﻠﺘﺮﻳﻨﮓ ﺁﺩﺭﺱ ﻫﺎﻱ ) ‪ : Control Media Access ) MAC‬ﺩﺭ ﺭﻭﺵ‬ ‫ﻓﻮﻕ‪ ،‬ﻟﻴﺴﺘﻲ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ MAC‬ﻣﺮﺑﻮﻁ ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ‪ ،‬ﺑﺮﺍﻱ‬

‫ﻳﮏ ‪ Point Access‬ﺗﻌﺮﻳﻒ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪ ،‬ﺻﺮﻓﺎ" ﺑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﮐﺎﻣـــﭙﻴﻮﺗﺮ ﺩﺭﺧﻮﺍﺳﺘﻲ ﺭﺍ ﺍﻳـــــﺠﺎﺩ‬ ‫ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﺁﺩﺭﺱ ‪ MAC‬ﺁﻥ ﺑﺎ ﺁﺩﺭﺱ ‪ MAC‬ﻣﻮﺟﻮﺩ ﺩﺭ ‪Access Point‬‬

‫ﻣﻘﺎﻳﺴﻪ ﺷﺪﻩ ﻭ ﺩﺭ ﺻﻮﺭﺕ ﻣﻄﺎﺑﻘﺖ ﺁﻧﺎﻥ ﺑﺎ ﻳﮑﺪﻳﮕﺮ‪ ،‬ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‬ ‫‪ .‬ﺍﻳﻦ ﺭﻭﺵ ﺍﺯ ﻟﺤﺎﻅ ﺍﻣﻨﻴﺘﻲ ﺷﺮﺍﻳﻂ ﻣﻨﺎﺳﺒﻲ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻭﻟﻲ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ‬ ‫ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﻫﺮ ﻳﮏ ﺍﺯ ﺁﺩﺭﺱ ﻫﺎﻱ ‪ MAC‬ﺭﺍ ﺑﺮﺍﻱ ﻫﺮ ‪ Access point‬ﺗﻌﺮﻳﻒ‬

‫ﻧﻤﻮﺩ‪ ،‬ﺯﻣﺎﻥ ﺯﻳﺎﺩﻱ ﺻﺮﻑ ﺧﻮﺍﻫﺪ ﺷﺪ‪ .‬ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺭﻭﺵ ﻓﻮﻕ‪ ،‬ﺻﺮﻓﺎ" ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﮐﻮﭼﮏ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﭘﻴﺸﻨﻬﺎﺩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﺷﺒﮑﻪ ‪Wireless‬‬ ‫ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺑﻪ ﺍﺑﻌﺎﺩ ﺷﺒﮑﻪ ﻣﻮﺭﺩ‬ ‫ﻧﻈﺮ ﺑﺴﺘﮕﯽ ﺩﺍﺭﺩ ‪ .‬ﻋﻠﻴﺮﻏﻢ ﻣﻮﺿﻮﻉ ﻓﻮﻕ ‪ ،‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ﺍﻏﻠﺐ ﻭ ﺷﺎﻳﺪ ﻫﻢ ﻗﻄﻌﺎ" ﺑﻪ‬ ‫ﻳﮏ ‪ access point‬ﻭ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺑﻮﺩ ‪ .‬ﺩﺭ ﺻﻮﺭﺗﯽ ﮐﻪ ﻗﺼﺪ‬

‫ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ﻣﻮﻗﺖ ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ‪ ،‬ﺻﺮﻓﺎ" ﺑﻪ ﺩﻭ ﮐﺎﺭﺕ ﺷﺒــﮑﻪ ﺑﺪﻭﻥ‬ ‫ﮐﺎﺑﻞ ﻧﻴﺎﺯ ﺧﻮﺍﻫﻴﺪ ﺩﺍﺷﺖ‪.‬‬

‫‪ Access Point‬ﭼﻴﺴﺖ ؟‬

‫ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻓﻮﻕ ‪ ،‬ﺑﻪ ﻋﻨﻮﺍﻥ ﻳﮏ ﭘﻞ ﺍﺭﺗﺒﺎﻃﯽ ﺑﻴﻦ ﺷﺒﮑﻪ ﻫﺎﯼ ﮐﺎﺑﻠﯽ ﻭ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ‬

‫ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻋﻤﻞ ﻣﯽ ﻧﻤﺎﻳﺪ ‪ .‬ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻓﻮﻕ‪ ،‬ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﭼﻨﺪﻳﻦ ﺩﺳﺘﮕﺎﻩ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺷﺒﮑﻪ ﻓﺮﺍﻫﻢ ﻣﯽ ﮔﺮﺩﺩ‪ point access.‬ﻣﯽ ﺗﻮﺍﻧﺪ ﺩﺍﺭﺍﯼ ﻋﻤﻠﮑﺮﺩﯼ‬

‫ﻣﺸﺎﺑﻪ ﻳﮏ ﺭﻭﺗﺮ ﻧﻴﺰ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﯼ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﻣﺤﺪﻭﺩﻩ ﻭﺳﻴﻌﺘﺮﯼ ﺍﻧﺠﺎﻡ‬ ‫ﺷﺪﻩ ﻭ ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ‪ point access‬ﺑﻪ ‪ access point‬ﺩﻳﮕﺮ ﺍﺭﺳﺎﻝ ﻣﯽ ﮔﺮﺩﺩ‪.‬‬ ‫ﻳﮏ ﻧﻤﻮﻧﻪ ﺩﺳﺘﮕﺎﻩ ‪access‬‬ ‫‪point‬‬

‫ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬

‫ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ‪ ،‬ﺑﻪ ﻳﮏ ﮐﺎﺭﺕ ﺷﺒﮑﻪ‬

‫ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻧﻴﺎﺯ ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ ‪ .‬ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ، Laptop‬ﻋﻤﻮﻣﺎ" ﺩﺍﺭﺍﯼ ﻳﮏ ﺍﺳﻼﺕ‬ ‫‪ PCMCIA‬ﺍﺳﺖ ﮐﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺩﺭﻭﻥ ﺁﻥ ﻗﺮﺍﺭ ﻣﯽ ﮔﻴﺮﺩ ‪ .‬ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﺷﺨﺼﯽ ﻧﻴﺰ ﺑﻪ‬ ‫ﻳﮏ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺩﺍﺧﻠﯽ ﮐﻪ ﻣﻌﻤﻮﻻ" ﺩﺍﺭﺍﯼ ﻳﮏ ﺁﻧﺘﻦ ﮐﻮﭼﮏ ﻭ ﻳﺎ ﺁﻧﺘﻦ ﺧﺎﺭﺟﯽ ﺍﺳﺖ‪ ،‬ﻧﻴﺎﺯ‬

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‫ﺧﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ ‪.‬ﺁﻧﺘﻦ ﻫﺎﯼ ﻓﻮﻕ ﺑﺮ ﺭﻭﯼ ﺍﻏﻠﺐ ﺩﺳﺘﮕﺎﻫﻬﺎ ‪،‬ﺍﺧﺘﻴﺎﺭﯼ ﺑﻮﺩﻩ ﻭ ﺍﻓﺰﺍﻳﺶ ﺳﻴﮕﻨﺎﻝ‬

‫ﺑﺮ ﺭﻭﯼ ﮐﺎﺭﺕ ﺭﺍ ﺑﺪﻧﺒﺎﻝ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﻳﮏ ﻧﻤﻮﻧﻪ ﮐﺎﺭﺕ ﺷﺒﮑﻪ ﺑﺪﻭﻥ‬ ‫ﮐﺎﺑﻞ‬

‫ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺍﺯ ﺩﻭ ﺭﻭﺵ ﻣﺘﻔﺎﻭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺭﻭﺵ ‪ : Infrastructure‬ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ‪ hosted ،‬ﻭ ﻳﺎ‬

‫‪ managed‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﯽ ﺷﻮﺩ ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﻭﺵ ﺍﺯ ﻳﮏ ﻭ ﻳﺎ ﭼﻨﺪﻳﻦ ‪access‬‬ ‫‪ ) point‬ﻣﻮﺳﻮﻡ ﺑﻪ ‪ gateway‬ﻭ ﻳﺎ ﺭﻭﺗﺮﻫﺎﯼ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ( ﮐﻪ ﺑﻪ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﻣﻮﺟﻮﺩ ﻣﺘﺼﻞ ﻣﯽ ﮔﺮﺩﻧﺪ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﯽ ﺷﻮﺩ ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﻨﺎﺑﻊ ﻣﻮﺟﻮﺩ ﺑﺮ ﺭﻭﯼ ﺷﺒﮑﻪ ﻧﻈﻴﺮ ﭼﺎﭘﮕﺮ ﻭ ﻳﺎ ﺍﻳﻨﺘﺮﻧﺖ ﺭﺍ ﺑﺪﺳﺖ‬

‫ﻣﯽ ﺁﻭﺭﻧﺪ‪.‬‬ ‫•‬

‫ﺭﻭﺵ ‪ : Ad-Hoc‬ﺑﻪ ﺍﻳﻦ ﻧﻮﻉ ﺷﺒﮑﻪ ﻫﺎ ‪ unmanaged ،‬ﻭ ﻳﺎ ‪peer to‬‬

‫‪ peer‬ﻧﻴﺰ ﮔﻔﺘﻪ ﻣﯽ ﺷﻮﺩ‪ .‬ﺩﺭ ﺭﻭﺵ ﻓﻮﻕ ﻫﺮ ﻳﮏ ﺍﺯ ﺩﺳﺘﮕﺎﻫﻬﺎ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﻳﮑﺪﻳﮕﺮ‬ ‫ﻣﺘﺼﻞ ﻣﯽ ﮔﺮﺩﻧﺪ‪.‬ﻣﺜﻼ" ﻳﮏ ﺷﺨﺺ ﺑﺎ ﺩﺍﺭﺍ ﺑﻮﺩﻥ ﻳﮏ ﺩﺳﺘﮕﺎﻩ ﮐﺎﻣﭙﻴﻮﺗﺮ ‪laptop‬‬ ‫ﻣﺴﺘﻘﺮ ﺩﺭ ﻣﺤﻮﻃﻪ ﻣﻨﺰﻝ ﺧﻮﺩ ﻣﯽ ﺗﻮﺍﺗﻨﺪ ﺑﺎ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺷﺨﺼﯽ ﻣﻮﺟﻮﺩ ﺩﺭ ﻣﻨﺰﻝ ﺧﻮﺩ‬ ‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺩﺳﺘﻴﺎﺑﯽ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﭘﺲ ﺍﺯ ﺗﻬﻴﻪ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﯼ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﻣﯽ ﺑﺎﻳﺴﺖ ﺗﻤﺎﻣﯽ ﺗﺠﻬﻴﺰﺍﺕ ﺗﻬﻴﻪ ﺷﺪﻩ ﺭﺍ ﺑﺎ ﻫﺪﻑ ﺍﻳﺠﺎﺩ ﻭ ﺳﺎﺯﻣﺎﻧﺪﻫﯽ ﻳﮏ ﺷﺒﮑﻪ ﺑﻪ‬

‫ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﺗﺎ ﺍﻣﮑﺎﻥ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺁﻧﺎﻥ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﻗﺒﻞ ﺍﺯ ﻧﺼﺐ ﻭ ﭘﻴﮑﺮﺑﻨﺪﯼ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺑﺪﻭﻥ ﮐﺎﺑﻞ‪ ،‬ﻻﺯﻡ ﺍﺳﺖ ﺑﻪ ﻣﻮﺍﺭﺩ ﺯﻳﺮ ﺩﻗﺖ ﻧﻤﺎﺋﻴﺪ‪:‬‬ ‫•‬

‫ﺗﻬﻴﻪ ﺩﺭﺍﻳﻮﺭﻫﺎﯼ ﻣﺮﺑﻮﻃﻪ ﺍﺯ ﻓﺮﻭﺷﻨﺪﻩ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﻭ ﮐﺴﺐ ﺁﺧﺮﻳﻦ ﺍﻃﻼﻋﺎﺕ ﻣﻮﺭﺩ‬

‫ﻧﻴﺎﺯ‬ ‫•‬

‫ﻓﺎﺻﻠﻪ ﺑﻴﻦ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﯽ ﺑﺎﻳﺴﺖ ﮐﻤﺘﺮ ﺍﺯ ﻳﮑﺼﺪ ﻣﺘﺮ ﺑﺎﺷﺪ‪.‬‬

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‫ﻫﺮ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﻣﻮﺟﻮﺩ ﻣﯽ ﺑﺎﻳﺴﺖ ﺑﺮ ﺭﻭﯼ ﻳﮏ ﻃﺒﻘﻪ ﻣﺸﺎﺑﻪ ﺑﺎﺷﻨﺪ‪.‬‬

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‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﯼ ﻣﺮﺑﻮﻁ ﺑﻪ ﻳﮏ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﻩ‪ ،‬ﺩﺍﺭﺍﯼ ﻣﺰﺍﻳﺎ ﻭ‬ ‫ﻣﻌﺎﻳﺒﯽ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﭘﻴﺸﻨﻬﺎﺩ ﻣﯽ ﮔﺮﺩﺩ ﻟﻴﺴﺘﯽ ﺍﺯ ﻭﻳﮋﮔﯽ ﻫﺎﯼ ﻫﺮ ﻳﮏ ﺍﺯ‬

‫ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﯼ ﻣﻮﺭﺩ ﻧﻴﺎﺯ ﻋﺮﺿﻪ ﺷﺪﻩ ﺗﻮﺳﻂ ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﻣﺘﻌﺪﺩ ﺗﻬﻴﻪ ﺷﻮﺩ ﺗﺎ‬ ‫ﺍﻣﮑﺎﻥ ﻣﻘﺎﻳﺴﻪ ﻭ ﺍﺧﺬ ﺗﺼﻤﻴﻢ ﻣﻨﺎﺳﺐ‪ ،‬ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪.‬‬

‫ﻣﺮﺍﺣﻞ ﻻﺯﻡ ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺼﺐ ﻳﮏ ﺷﺒﮑﻪ ) ﻓﺮﺿﻴﺎﺕ ‪ :‬ﻣﺎ ﺩﺍﺭﺍﯼ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﺑﻠﯽ ﻣﻮﺟﻮﺩ‬

‫ﻫﺴﺘﻴﻢ ﻭ ﻗﺼﺪ ﭘﻴﺎﺩﻩ ﺳﺎﺯﯼ ﻳﮏ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺩﺳﺘﮕﺎﻫﻬﺎﯼ ﺑﺪﻭﻥ ﮐﺎﺑﻞ‬ ‫ﺑﻪ ﺁﻥ ﺭﺍ ﺩﺍﺭﻳﻢ (‪:‬‬ ‫•‬

‫ﺍﺗﺼﺎﻝ ‪ point access‬ﺑﻪ ﺑﺮﻕ ﻭ ﺳﻮﮐﺖ ﻣﺮﺑﻮﻁ ﺑﻪ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ‬

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‫ﭘﻴﮑﺮﺑﻨﺪﯼ ‪ ) access point‬ﻣﻌﻤﻮﻻ" ﺍﺯ ﻃﺮﻳﻖ ﻳﮏ ﻣﺮﻭﺭﮔﺮ ﻭﺏ ( ﺗﺎ ﺍﻣﮑﺎﻥ‬ ‫ﻣﺸﺎﻫﺪﻩ ﺁﻥ ﺗﻮﺳﻂ ﺷﺒﮑﻪ ﻣﻮﺟﻮﺩ ﻓﺮﺍﻫﻢ ﮔﺮﺩﺩ‪ .‬ﻧﺤﻮﻩ ﭘﻴﮑﺮﺑﻨﺪﯼ ‪point access‬‬ ‫ﺑﺴﺘﮕﯽ ﺑﻪ ﻧﻮﻉ ﺁﻥ ﺩﺍﺭﺩ‪.‬‬

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‫ﭘﻴﮑﺮﺑﻨﺪﯼ ﻣﻨﺎﺳﺐ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎﯼ ﺳﺮﻭﻳﺲ ﮔﻴﺮﻧﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ‪access‬‬ ‫‪ ) point‬ﺩﺭ ﺻﻮﺭﺗﯽ ﮐﻪ ﺗﻤﺎﻣﯽ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﯼ ﺷﺒﮑﻪ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﺍﺯ ﻳﮏ ﺗﻮﻟﻴﺪ‬ ‫ﮐﻨﻨﺪﻩ ﺗﻬﻴﻪ ﺷﺪﻩ ﺑﺎﺷﻨﺪ ‪ ،‬ﻋﻤﻮﻣﺎ" ﺑﺎ ﺗﻨﻈﻴﻤﺎﺕ ﭘﻴﺶ ﻓﺮﺽ ﻫﻢ ﻣﯽ ﺗﻮﺍﻥ ﺷﺒﮑﻪ ﺭﺍ ﻓﻌﺎﻝ‬ ‫ﻧﻤﻮﺩ ‪ .‬ﺑﻪ ﻫﺮ ﺣﺎﻝ ﭘﻴﺸﻨﻬﺎﺩ ﻣﯽ ﮔﺮﺩﺩ ﻫﻤﻮﺍﺭﻩ ﺑﻪ ﺭﺍﻫﻨﻤﺎﯼ ﺳﺨﺖ ﺍﻓﺰﺍﺭ ﺗﻬﻴﻪ ﺷﺪﻩ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﭘﻴﮑﺮﺑﻨﺪﯼ ﺑﻬﻴﻨﻪ ﺁﻧﺎﻥ ‪ ،‬ﻣﺮﺍﺟﻌﻪ ﮔﺮﺩﺩ(‪.‬‬ ‫‪375‬‬

‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﻣﻴﺰﺍﻥ ﺗﺎﺧﻴﺮ‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺍﺯ ﺟﻤﻠﻪ ﻭﺍﮊﻩ ﻫﺎﻱ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺩﻧﻴﺎﻱ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ ﮐﻪ ﺑﻪ‬

‫ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺗﻮﺳﻂ ﻳﮏ ﺍﺗﺼﺎﻝ ﺷﺒﮑﻪ ﻭ ﻳﺎ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ‪ ،‬ﺍﺷﺎﺭﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺍﻳﻦ ﻭﺍﮊﻩ ﺍﺯ‬

‫ﺭﺷﺘﻪ ﻣﻬﻨﺪﺳﻲ ﺑﺮﻕ ﺍﻗﺘﺒﺎﺱ ﺷﺪﻩ ﺍﺳﺖ‪ .‬ﺩﺭ ﺍﻳﻦ ﺷﺎﺧﻪ ﺍﺯ ﻋﻠﻮﻡ‪ ،‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻧﺸﺎﻥ ﺩﻫﻨﺪﻩ‬ ‫ﻣﺠﻤﻮﻉ ﻓﺎﺻﻠﻪ ﻭ ﻳﺎ ﻣﺤﺪﻭﺩﻩ ﺑﻴﻦ ﺑﺎﻻﺗﺮﻳﻦ ﻭ ﭘﺎﺋﻴﻦ ﺗﺮﻳﻦ ﺳﻴﮕﻨﺎﻝ ﺑﺮ ﺭﻭﻱ ﮐﺎﻧﺎﻝ ﻫﺎﻱ‬

‫ﻣﺨﺎﺑﺮﺍﻧﻲ ) ﺑﺎﻧﺪ (‪ ،‬ﺍﺳﺖ‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺳـﻨﺠﺶ ﺍﻧﺪﺍﺯﻩ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺍﺯ ﻭﺍﺣﺪ " ﺗﻌـــﺪﺍﺩ ﺑﺎﻳﺖ‬ ‫ﺩﺭﺛﺎﻧﻴﻪ " ﻭ ﻳﺎ ‪ bps‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺗﻨﻬﺎ ﻋﺎﻣﻞ ﺗﻌﻴﻴﻦ ﮐﻨﻨﺪﻩ ﺳﺮﻋﺖ ﻳﮏ ﺷﺒﮑﻪ ﺍﺯ ﺯﺍﻭﻳﻪ ﮐﺎﺭﺑﺮﺍﻥ ﻧﺒﻮﺩﻩ ﻭ ﻳﮑﻲ ﺩﻳﮕﺮ‬ ‫ﺍﺯ ﻋﻨﺎﺻﺮ ﺗﺎﺛﻴﺮﮔﺬﺍﺭ‪" ،‬ﻣﻴﺰﺍﻥ ﺗﺎﺧﻴﺮ" ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ ﮐﻪ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺭﺍ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺷﺒﮑﻪ ﺍﺟﺮﺍﺀ ﻣﻲ ﮔﺮﺩﻧﺪ‪ ،‬ﺗﺤﺖ ﺗﺎﺛﻴﺮ ﻗﺮﺍﺭ ﺩﻫﺪ‪.‬‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﭼﻴﺴﺖ ؟‬ ‫ﺗﻮﻟﻴﺪ ﮐﻨﻨﺪﮔﺎﻥ ﺗﺠﻬﻴﺰﺍﺕ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻱ ﺷﺒﮑﻪ ﺩﺭ ﺯﻣﺎﻥ ﺍﺭﺍﺋﻪ ﻣﺤﺼﻮﻻﺕ ﺧﻮﺩ ﺗﺒﻠﻴﻐﺎﺕ‬

‫ﺯﻳﺎﺩﻱ ﺭﺍ ﺩﺭ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‪ ،‬ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﺍﮐﺜﺮ ﮐﺎﺭﺑﺮﺍﻥ ﺍﻳﻨﺘﺮﻧﺖ ﻧﺴﺒﺖ ﺑﻪ ﻣﻴﺰﺍﻥ‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻮﺩﻡ ﺧﻮﺩ ﻭ ﻳﺎ ﺳﺮﻭﻳﺲ ﺍﻳﻨﺘﺮﻧﺖ ‪ braodband‬ﺩﺍﺭﺍﻱ ﺁﮔﺎﻫﻲ ﻻﺯﻡ‬ ‫ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‪ ،‬ﻇﺮﻓﻴﺖ ﺍﺗﺼﺎﻝ ﺍﻳﺠﺎﺩ ﺷﺪﻩ ﺭﺍ ﻣﺸﺨﺺ ﻧﻤﻮﺩﻩ ﻭ ﺑﺪﻳﻬﻲ ﺍﺳﺖ ﮐﻪ ﻫﺮ‬ ‫ﺍﻧﺪﺍﺯﻩ ﻇﺮﻓﻴﺖ ﻓﻮﻕ ﺑﻴﺸﺘﺮ ﺑﺎﺷﺪ‪ ،‬ﺍﻣﮑﺎﻥ ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﻣﻨﺎﺑﻊ ﺷﺒﮑﻪ ﺑﺎ ﺳﺮﻋﺖ ﺑﻴﺸﺘﺮﻱ ﻓﺮﺍﻫﻢ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‪ ،‬ﻇﺮﻓﻴﺖ ﺗﺌﻮﺭﻱ ﻭ ﻳﺎ ﻋﻤﻠﻲ ﻳﮏ ﺍﺗﺼﺎﻝ ﺷﺒﮑﻪ ﻭ ﻳﺎ ﻳﮏ ﺍﻳﻨﺘﺮﻓﻴﺲ ﺭﺍ‬ ‫ﻣﺸﺨﺺ ﻧﻤﻮﺩﻩ ﮐﻪ ﺩﺭ ﻋﻤﻞ ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻣﺘﻔﺎﻭﺕ ﺑﺎﺷﻨﺪ‪ .‬ﻣﺜﻼ" ﻳﮏ ﻣﻮﺩﻡ ‪V.90‬‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪﻱ ﻣﻌﺎﺩﻝ ‪ kbps ٥٦‬ﺭﺍ ﺩﺭ ﺣﺎﻟﺖ ﺳﻘﻒ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺣﻤﺎﻳﺖ ﻣﻲ ﻧﻤﺎﻳﺪ ﻭﻟﻲ ﺑﺎ‬ ‫ﺗﻮﺟﻪ ﺑﻪ ﻣﺤﺪﻭﺩﻳﺖ ﻫﺎﻱ ﺧﻄﻮﻁ ﺗﻠﻔﻦ ﻭ ﺳﺎﻳﺮ ﻋﻮﺍﻣﻞ ﻣﻮﺟﻮﺩ‪ ،‬ﻋﻤﻼ" ﺍﻣﮑﺎﻥ ﺭﺳﻴﺪﻥ ﺑﻪ‬ ‫ﻣﺤﺪﻭﺩﻩ ﻓﻮﻕ ﻭﺟﻮﺩ ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ ‪ .‬ﻳﮏ ﺷﺒﮑﻪ ﺍﺗﺮﻧﺖ ﺳﺮﻳﻊ ﻧﻴﺰ ﺍﺯ ﻟﺤﺎﻅ ﺗﺌﻮﺭﻱ ﻗﺎﺩﺭ ﺑﻪ‬

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‫ﺣﻤﺎﻳﺖ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪﻱ ﻣﻌﺎﺩﻝ ‪ Mbps١٠٠‬ﺍﺳﺖ‪ ،‬ﻭﻟﻲ ﻋﻤﻼ" ﺍﻳﻦ ﻭﺿﻌﻴﺖ ﺩﺭ ﻋﻤﻞ ﻣﺤﻘﻖ‬

‫ﻧﺨﻮﺍﻫﺪ ﺷﺪ ) ﺗﻔﺎﻭﺕ ﻇﺮﻓﻴﺖ ﺗﺌﻮﺭﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎ ﻇﺮﻓﻴﺖ ﻭﺍﻗﻌﻲ(‪.‬‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎﻻ ﻭ ‪broadband‬‬

‫ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﻭﺍﮊﻩ ﻫﺎﻱ "ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎﻻ" ﻭ " ‪ " braodband‬ﺑﻪ ﺟﺎﻱ ﻳﮑﺪﻳﮕﺮ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﮐﺎﺭﺷﻨﺎﺳﺎﻥ ﺷﺒﮑﻪ ﺩﺭ ﺑﺮﺧﻲ ﻣﻮﺍﺭﺩ ﺍﺯ ﻭﺍﮊﻩ "ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎﻻ " ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﻣﺸﺨﺺ ﻧﻤﻮﺩﻥ ﺳﺮﻋﺖ ﺑﺎﻻﻱ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺗﻌﺎﺭﻳﻒ‬ ‫ﻣﺘﻔﺎﻭﺗﻲ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ‪ .‬ﺍﻳﻦ ﻧﻮﻉ ﺍﺗﺼﺎﻻﺕ‪ ،‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪﻱ ﺑﻴﻦ ‪ Kbps٦٤‬ﺗﺎ ‪ kbps٣٠٠‬ﻭ ﻳﺎ‬ ‫ﺑﻴﺸﺘﺮ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧـﻤﺎﻳﻨﺪ‪ .‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎﻻ ﺑﺎ ‪ broadband‬ﻣﺘﻔﺎﻭﺕ ﺍﺳﺖ‪.‬‬ ‫‪ ، broadband‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺭﻭﺵ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﻳﮏ ﺍﺭﺗﺒﺎﻁ ﺍﺳﺖ ﺩﺭ‬

‫ﺻﻮﺭﺗﻲ ﮐﻪ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ‪ ،‬ﻧﺮﺥ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺍﺯ ﻃﺮﻳﻖ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬ ‫ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺷﺒﮑﻪ‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺍﺗﺼﺎﻝ ﺷﺒﮑﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺍﺑﺰﺍﺭﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻧﻤﻮﺩ ‪ .‬ﺑﺮﺍﻱ ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺤﻠﻲ ) ‪ ، ( LAN‬ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﺋﻲ ﻧﻈﻴﺮ‬ ‫‪ netpref‬ﻭ ‪ ، ttcp‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﺍﺗﺼﺎﻝ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﻭ ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺴﺖ‬

‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ‪ .‬ﺗﻌﺪﺍﺩ ﺯﻳﺎﺩﻱ ﺍﺯ ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ‬ ‫ﺭﺍ ﻣﻲ ﺗﻮﺍﻥ ﺑﺎ ﻣﺮﺍﺟﻌﻪ ﺑﻪ ﺻﻔﺤﺎﺕ ﻭﺏ ﻋﻤﻮﻣﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ‪ .‬ﺻﺮﻓﻨﻈﺮ ﺍﺯ ﻧﻮﻉ ﻧﺮﻡ ﺍﻓﺰﺍﺭﻱ‬ ‫ﮐﻪ ﺍﺯ ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺩﺍﺭﺍﻱ ﻣﺤﺪﻭﺩﻩ‬

‫ﺑﺴﻴﺎﺭ ﻣﺘﻐﻴﺮﻱ ﺍﺳﺖ ﮐﻪ ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﺩﻗﻴﻖ ﺁﻥ ﺍﻣﺮﻱ ﻣﺸﮑﻞ ﺍﺳﺖ‪.‬‬ ‫ﺗﺎﺧﻴﺮ‬

‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪﺻﺮﻓﺎ" ﻳﮑﻲ ﺍﺯ ﻋﻨﺎﺻﺮﺗﺎﺛﻴﺮﮔﺬﺍﺭ ﺩﺭﺳﺮﻋﺖ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ‪.‬‬

‫ﺗﺎﺧﻴﺮ)‪ ( Latency‬ﮐﻪ ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﻣﻴﺰﺍﻥ ﺗﺎﺧﻴﺮ ﺩﺭ ﭘﺮﺩﺍﺯﺵ ﺩﺍﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﺍﺳﺖ‪،‬‬

‫ﻳﮑﻲ ﺩﻳﮕﺮ ﺍﺯ ﻋﻨﺎﺻﺮ ﻣﻬﻢ ﺩﺭ ﺍﺭﺯﻳﺎﺑﻲ ﮐﺎﺭﺁﺋﻲ ﻭ ﺳﺮﻋﺖ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺖ ﮐﻪ ﺩﺍﺭﺍﻱ‬ ‫ﺍﺭﺗﺒﺎﻃﻲ ﻧﺰﺩﻳﮏ ﺑﺎ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺍﺯ ﻟﺤﺎﻅ ﺗﺌﻮﺭﻱ ﺳﻘﻒ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺛﺎﺑﺖ‬ ‫‪377‬‬

‫ﺍﺳﺖ‪ .‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭﺍﻗﻌﻲ ﻣﺘﻐﻴﺮ ﺑﻮﺩﻩ ﻭ ﻣﻲ ﺗﻮﺍﻧﺪ ﻋﺎﻣﻞ ﺑﺮﻭﺯ ﺗﺎﺧﻴﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﮔﺮﺩﺩ‪ .‬ﻭﺟﻮﺩ ﺗﺎﺧﻴﺮ ﺯﻳﺎﺩ ﺩﺭ ﭘﺮﺩﺍﺯﺵ ﺩﺍﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻭ ﺩﺭ ﻳﮏ ﻣﺤﺪﻭﺩﻩ ﺯﻣﺎﻧﻲ ﮐﻮﺗﺎﻩ‬ ‫ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺑﺮﻭﺯ ﻳﮏ ﺑﺤﺮﺍﻥ ﺩﺭ ﺷﺒﮑﻪ ﺷﺪﻩ ﻭ ﭘﻴﺎﻣﺪ ﺁﻥ ﭘﻴﺸﮕﻴﺮﻱ ﺍﺯ ﺣﺮﮐﺖ‬ ‫ﺩﺍﺩﻩ ﺑﺮ ﺭﻭﻱ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ ﻭ ﮐﺎﻫﺶ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻮﺛﺮ ﺍﺯ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﺎﺷﺪ‪.‬‬ ‫ﺗﺎﺧﻴﺮ ﻭ ﺳﺮﻭﻳﺲ ﺍﻳﻨﺘﺮﻧﺖ ﻣﺎﻫﻮﺍﺭﻩ ﺍﻱ‬

‫ﺩﺳﺘﻴﺎﺑﻲ ﺑﻪ ﺍﻳﻨﺘﺮﻧﺖ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺎﻫﻮﺍﺭﻩ ﺑﻪ ﺧﻮﺑﻲ ﺗﻔﺎﻭﺕ ﺑﻴﻦ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﺗﺎﺧﻴﺮ‬

‫ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ ‪ .‬ﺍﺭﺗﺒﺎﻃﺎﺕ ﻣﺒﺘﻨﻲ ﺑﺮ ﻣﺎﻫﻮﺍﺭﻩ ﺩﺍﺭﺍﻱ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﺗﺎﺧﻴﺮ ﺑﺎﻻﺋﻲ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﻣﺜﻼ" ﺯﻣﺎﻧﻲ ﮐﻪ ﮐﺎﺭﺑﺮﻱ ﺩﺭﺧﻮﺍﺳﺖ ﻳﮏ ﺻﻔﺤﻪ ﻭﺏ ﺭﺍ ﻣﻲ ﻧﻤﺎﺋﻴﺪ‪ ،‬ﻣﺪﺕ ﺯﻣﺎﻧﻲ ﮐﻪ ﺑﻄﻮﻝ‬

‫ﻣﻲ ﺍﻧﺠﺎﻣﺪ ﺗﺎ ﺻﻔﺤﻪ ﺩﺭﺣﺎﻓﻈﻪ ﻣﺴﺘﻘﺮ ﮔﺮﺩﺩ ﺑﺎ ﺍﻳﻦ ﮐﻪ ﮐﻮﺗﺎﻩ ﺑﻨﻈﺮ ﻣﻲ ﺁﻳﺪ ﻭﻟﻲ ﮐﺎﻣﻼ"‬ ‫ﻣﻠﻤﻮﺱ ﺍﺳﺖ‪ .‬ﺗﺎﺧﻴﺮ ﻓﻮﻕ ﺑﻪ ﺩﻟﻴﻞ ﺗﺎﺧﻴﺮ ﺍﻧﺘﺸﺎﺭ ﺍﺳﺖ‪ .‬ﻋﻼﻭﻩ ﺑﺮ ﺗﺎﺧﻴﺮ ﺍﻧﺘﺸﺎﺭ‪ ،‬ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺎ ﻧﻮﻉ ﻫﺎﻱ ﺩﻳﮕﺮﻱ ﺍﺯ ﺗﺎﺧﻴﺮ ﻣﻮﺍﺟﻪ ﮔﺮﺩﺩ‪ .‬ﺗﺎﺧﻴﺮ ﺍﻧﺘﻘﺎﻝ )ﻣﺮﺗﺒﻂ ﺑﺎ ﺧﺼﺎﻳﺺ‬

‫ﻓﻴﺰﻳﮑﻲ ﻣﺤﻴﻂ ﺍﻧﺘﻘﺎﻝ( ﻭ ﺗﺎﺧﻴﺮ ﭘﺮﺩﺍﺯﺵ )ﺍﺭﺳﺎﻝ ﺩﺭﺧﻮﺍﺳﺖ ﺍﺯ ﻃﺮﻳﻖ ﺳﺮﻭﻳﺲ ﺩﻫﻨﺪﮔﺎﻥ‬

‫ﭘﺮﻭﮐﺴﻲ ﻭ ﻳﺎ ﺍﻳﺠﺎﺩ ‪ hops‬ﺑﺮ ﺭﻭﻱ ﺍﻳﻨﺘﺮﻧﺖ( ﺩﻭ ﻧﻤﻮﻧﻪ ﻣﺘﺪﺍﻭﻝ ﺩﺭ ﺍﻳﻦ ﺯﻣﻴﻨﻪ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﺗﺎﺧﻴﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ‬

‫ﺍﺯ ﺍﺑﺰﺍﺭﻫﺎﻱ ﺷﺒﮑﻪ ﺍﻱ ﻣﺘﻌﺪﺩﻱ ﻧﻈﻴﺮ ‪ ping‬ﻭ ‪ traceroute‬ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺍﻧﺪﺍﺯﻩ ﮔﻴﺮﻱ ﻣﻴﺰﺍﻥ ﺗﺎﺧﻴﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ‪ .‬ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻓﻮﻕ ﻓﺎﺻﻠﻪ ﺯﻣﺎﻧﻲ ﺑﻴﻦ‬

‫ﺍﺭﺳﺎﻝ ﻳﮏ ﺑﺴﺘﻪ ﺍﻃﻼﻋﺎﺗﻲ ﺍﺯ ﻣﺒﺪﺍﺀ ﺑﻪ ﻣﻘﺼﺪ ﻭ ﺑﺮﮔﺸﺖ ﺁﻥ ﺭﺍ ﻣﺤﺎﺳﺒﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺑﻪ ﺯﻣﺎﻥ‬ ‫ﻓﻮﻕ ‪ ، round-trip‬ﮔﻔﺘﻪ ﻣﻲ ﺷﻮﺩ‪ round-trip .‬ﺗﻨﻬﺎ ﺭﻭﺵ ﻣﻮﺟﻮﺩ ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺗﺸﺨﻴﺺ ﻭ ﻳﺎ ﺑﺪﺳﺖ ﺁﻭﺭﺩﻥ ﻣﻴﺰﺍﻥ ﺗﺎﺧﻴﺮ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﻧﺒﻮﺩﻩ ﻭ ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ‬

‫ﺑﺮﻧﺎﻣﻪ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

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‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﺗﺎﺧﻴﺮ ﺩﻭ ﻋﻨﺼﺮ ﺗﺎﺛﻴﺮ ﮔﺬﺍﺭ ﺩﺭ ﮐﺎﺭﺍﺋﻲ ﻳﮏ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﺷﻨﺪ ‪.‬ﻣﻌﻤﻮﻻ" ﺍﺯ ﻭﺍﮊﻩ‬

‫) ‪ QoS ( Quality of Service‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻧﺸﺎﻥ ﺩﺍﺩﻥ ﻭﺿﻌﻴﺖ ﮐﺎﺭﺁﺋﻲ ﻳﮏ ﺷﺒﮑﻪ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﺩﺭ ﺁﻥ ﺩﻭ ﺷﺎﺧﺺ ﻣﻬﻢ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻭ ﺗﺎﺧﻴﺮ ﻣﻮﺭﺩ ﺗﻮﺟﻪ ﻗﺮﺍﺭ‬ ‫ﻣﻲ ﮔﻴﺮﺩ‪.‬‬

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‫ﺍﻧﻮﺍﻉ ﮐﺎﺑﻞ‬ ‫ﺍﻣﺮﻭﺯﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻣﺨﺘﻠﻔﻲ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻧﻮﻉ ﻭ ﺳﻴﺴﺘﻢ ﮐﺎﺑﻞ‬ ‫ﮐﺸﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﻳﮏ ﺷﺒﮑﻪ ﺑﺴﻴﺎﺭ ﺣﺎﺋﺰ ﺍﻫﻤﻴﺖ ﺍﺳﺖ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﺩﺍﺷﺘﻦ‬ ‫ﺷﺒﮑﻪ ﺍﻱ ﺭﺍ ﺩﺍﺭﻳﻢ ﮐﻪ ﺩﺍﺭﺍﻱ ﺣﺪﺍﻗﻞ ﻣﺸﮑﻼﺕ ﺑﺎﺷﺪ ﻭ ﺑﺘﻮﺍﻧﺪ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻔﻴﺪ ﺍﺯ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ‬

‫ﺑﻪ ﺩﺭﺳﺘﻲ ﺧﺪﻣﺎﺕ ﺧﻮﺩ ﺭﺍ ﺩﺭ ﺍﺧﺘﻴﺎﺭ ﮐﺎﺭﺑﺮﺍﻥ ﻗﺮﺍﺭ ﺩﻫﺪ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﻳﮏ ﺳﻴﺴﺘﻢ‬ ‫ﮐﺎﺑﻠﻴﻨﮓ ﻣﻨﺎﺳﺐ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺯﻣﺎﻥ ﻃﺮﺍﺣﻲ ﻳﮏ ﺷﺒﮑﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺭﻋﺎﻳﺖ ﻣﺠﻤﻮﻋﻪ‬ ‫ﻗﻮﺍﻧﻴﻦ ﻣﻮﺟﻮﺩ ﺩﺭ ﺧﺼﻮﺹ ﺳﻴﺴﺘﻢ ﮐﺎﺑﻠﻴﻨﮓ‪ ،‬ﺷﺒﮑﻪ ﺍﻱ ﺑﺎ ﺣﺪﺍﻗﻞ ﻣﺸﮑﻼﺕ ﺭﺍ ﻃﺮﺍﺣﻲ‬

‫ﻧﻤﻮﺩ‪.‬ﺑﺎ ﺍﻳﻦ ﮐﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺷﺒﮑﻪ ﻫﺎﻱ ﺑﺪﻭﻥ ﮐﺎﺑﻞ ﻧﻴﺰ ﺩﺭ ﺍﺑﻌﺎﺩ ﻭﺳﻴﻌﻲ ﮔﺴﺘﺮﺵ ﻳﺎﻓﺘﻪ ﺍﺳﺖ‪،‬‬ ‫ﻭﻟﻲ ﻫﻨﻮﺯ ﺑﻴﺶ ﺍﺯ ‪ ٩٥‬ﺩﺭﺻﺪ ﺳﺎﺯﻣﺎﻥ ﻫﺎ ﻭ ﻣﻮﺳﺴﺎﺕ ﺍﺯ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺷﺒﮑﻪ ﺍﻱ ﻣﺒﺘﻨﻲ ﺑﺮ‬ ‫ﮐﺎﺑﻞ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬ ‫ﺍﻳﺪﻩ ﻫﺎﻱ ﺍﻭﻟﻴﻪ‬ ‫ﺍﻳﺪﻩ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﺑﻪ ﺻﻮﺭﺕ ﺩﻳﺠﻴﺘﺎﻝ‪ ،‬ﺗﻔﮑﺮﻱ ﺟﺪﻳﺪ ﺩﺭ ﻋﺼﺮ ﺣﺎﺿﺮ ﻣﺤﺴﻮﺏ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭﺳﺎﻝ ‪ ١٨٤٤‬ﻓﺮﺩﻱ ﺑﺎ ﻧﺎﻡ"ﺳﺎﻣﻮﺋﻞ ﻣﻮﺭﺱ"‪ ،‬ﻳﮏ ﭘﻴﺎﻡ ﺭﺍ ﺍﺯ‬

‫‪Washington D.C‬‬

‫ﺑﻪ ‪ Baltimore‬ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﺍﺧﺘﺮﺍﻉ ﺟﺪﻳﺪ ﺧﻮﺩ )ﺗﻠﮕﺮﺍﻑ(‪ ،‬ﺍﺭﺳﺎﻝ ﻧﻤﻮﺩ‪ .‬ﺑﺎ ﺍﻳﻦ ﮐﻪ ﺍﺯ ﺁﻥ‬ ‫ﻣﻮﻗﻊ ﺯﻣﺎﻧﻲ ﺯﻳﺎﺩﻱ ﮔﺬﺷﺘﻪ ﺍﺳﺖ ﻭ ﻣﺎ ﺍﻣﺮﻭﺯﻩ ﺷﺎﻫﺪ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺑﺰﺭﮒ ﻭ ﺩﺭ ﻋﻴﻦ‬

‫ﺣﺎﻝ ﭘﻴﭽﻴﺪﻩ ﺍﻱ ﻣﻲ ﺑﺎﺷﻴﻢ ﻭﻟﻲ ﻣﻲ ﺗﻮﺍﻥ ﺍﺩﻋﺎ ﻧﻤﻮﺩ ﮐﻪ ﺍﺻﻮﻝ ﮐﺎﺭ ‪ ،‬ﻫﻤﺎﻥ ﺍﺻﻮﻝ ﻭ ﻣﻔﺎﻫﻴﻢ‬

‫ﮔﺬﺷﺘﻪ ﺍﺳﺖ‪.‬‬ ‫ﮐﺪﻫﺎﻱ ﻣﻮﺭﺱ‪ ،‬ﻧﻮﻉ ﺧﺎﺻﻲ ﺍﺯ ﺳﻴﺴﺘﻢ ﺑﺎﻳﻨﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ ﮐﻪ ﺍﺯ ﻧﻘﻄﻪ ﻭ ﺧﻂ ﻓﺎﺻﻠﻪ ﺑﺎ‬

‫ﺗﺮﮐﻴﺒﺎﺕ ﻣﺘﻔﺎﻭﺕ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺍﺋﻪ ﺣﺮﻭﻑ ﻭ ﺍﻋﺪﺍﺩ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺷﺒﮑﻪ ﻫﺎﻱ ﻣﺪﺭﻥ‬ ‫ﺩﺍﺩﻩ ﺍﺯ ﻳﮏ ﻭ ﺻﻔﺮ ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ ‪ .‬ﺑﺰﮔﺘﺮﻳﻦ ﺗﻔﺎﻭﺕ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺳﻴﺴـﺘﻢ ﻫﺎﻱ ﻣﺪﺭﻥ‬ ‫ﻣﺒـــﺎﺩﻟﻪ ﺍﻃﻼﻋﺎﺕ ﻭ ﺳﻴﺴﺘــﻢ ﭘﻴﺸــﻨﻬﺎﺩﻱ "ﻣﻮﺭﺱ "‪ ،‬ﺳﺮﻋـﺖ ﻣﺒﺎﺩﻟﻪ ﺍﻃﻼﻋــﺎﺕ ﺩﺭ ﺁﻧﺎﻥ‬

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‫ﺍﺳﺖ‪.‬ﺗﻠﮕﺮﺍﻑ ﻫﺎﻱ ﺍﻭﺍﺳﻂ ﻗﺮﻥ ‪ ، ١٩‬ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﭼﻬﺎﺭ ﺗﺎ ﭘﻨﺞ ﻧﻘﻄﻪ ﻭ ﻳﺎ ﺧﻂ ﻓﺎﺻﻠﻪ ﺩﺭ‬

‫ﻫﺮ ﺛﺎﻧﻴﻪ ﺑﻮﺩﻧﺪ ‪ ،‬ﺩﺭ ﺣﺎﻟﻲ ﮐﻪ ﻫﻢ ﺍﻳﻨﮏ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ ﺑﺎ ﺳﺮﻋﺘﻲ ﻣﻌﺎﺩﻝ ﻳﮏ ﮔﻴﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺍﺭﺗﺒﺎﻁ ﺑﺮﻗﺮﺍﺭ ﻣﻲ ﻧﻤﺎﻳﻨﺪ )ﺍﺭﺳﺎﻝ ‪ ١،٠٠٠،٠٠٠،٠٠٠‬ﺻﻔﺮ ﻭ ﻳﺎ ﻳﮏ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ(‪.‬‬ ‫ﺗﻠﮕﺮﺍﻑ ﻭ ﺗﻠﻪ ﺗﺎﻳﭗ ﺭﺍﻳﺘﺮ ‪ ،‬ﭘﻴﺸﮕﺎﻡ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﻣﻲ ﺑﺎﺷﻨﺪ ‪ .‬ﺩﺭ ﻃﻲ ﺳﻲ ﻭ ﭘﻨﺞ ﺳﺎﻝ ﺍﺧﻴﺮ‬ ‫ﻫﻤﻪ ﭼﻴﺰ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﻭ ﻏﻴﺮﻗﺎﺑﻞ ﺗﺼﻮﺭﻱ ﺗﻐﻴﻴﺮ ﻧﻤﻮﺩﻩ ﺍﺳﺖ‪ .‬ﺿﺮﻭﺭﺕ ﺍﺭﺗﺒﺎﻁ ﮐﺎﻣﭙﻴﻮﺗﺮﻫﺎ‬

‫ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﻭ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ‪ ،‬ﻣﻬﻤﺘﺮﻳﻦ ﻋﻠﻞ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺗﺠﻬﻴﺰﺍﺕ ﺷﺒﮑﻪ ﺍﻱ ﺳﺮﻳﻊ‪ ،‬ﮐﺎﺑﻞ‬ ‫ﻫﺎﺋﻲ ﺑﺎ ﻣﺸﺨﺼﺎﺕ ﺑﺎﻻ ﻭ ﺳﺨﺖ ﺍﻓﺰﺍﺭﻫﺎﻱ ﺍﺭﺗﺒﺎﻃﻲ ﭘﻴﺸﺮﻓﺘﻪ ﺍﺳﺖ‪.‬‬ ‫ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﺗﮑﻨﻮﻟﻮﮊﻱ ﻫﺎﻱ ﺟﺪﻳﺪ ﺷﺒﮑﻪ‬

‫ﺍﺗﺮﻧﺖ ﺩﺭ ﺳﺎﻝ ‪ ١٩٧٠‬ﺗﻮﺳﻂ ﺷﺮﮐﺖ ﺯﻳﺮﺍﮐﺲ ﻭ ﺩﺭ ﻣﺮﮐﺰ ﺗﺤﻘﻴﻘﺎﺕ ‪ Palo Alto‬ﺩﺭ‬

‫ﮐﺎﻟﻴﻔﺮﻧﻴﺎ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﮔﺮﺩﻳﺪ‪ .‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٧٩‬ﺷﺮﮐﺖ ﻫﺎﻱ ‪ DEC‬ﻭ ﺍﻳﻨﺘﻞ ﺑﺎ ﭘﻴﻮﺳﺘﻦ ﺑﻪ‬ ‫ﺯﻳﺮﺍﮐﺲ‪ ،‬ﺳﻴﺴﺘﻢ ﺍﺗﺮﻧﺖ ﺭﺍ ﺑﺮﺍﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻋﻤﻮﻡ‪ ،‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻧﻤﻮﺩﻧﺪ‪ .‬ﺍﻭﻟﻴﻦ ﻣﺸﺨﺼﻪ‬ ‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٠‬ﺗﻮﺳﻂ ﺳﻪ ﺷﺮﮐﺖ ﻓﻮﻕ ﻭ ﺑﺎ ﻧﺎﻡ ‪Ethernet Blue Book‬‬ ‫ﺍﺭﺍﺋﻪ ﮔﺮﺩﻳﺪ ‪ ) .‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪.( DIX‬‬

‫ﺍﺗﺮﻧﺖ ﻳﮏ ﺳﻴﺴﺘﻢ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺳﺖ ) ﺩﻩ ﻣﻴﻠﻴﻮﻥ ﺻﻔﺮ ﻭ ﻳﺎ ﻳﮏ ﺩﺭ ﺛﺎﻧﻴﻪ( ﮐﻪ ﺍﺯ‬ ‫ﻳﮏ ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻝ ﺑﺰﺭﮒ ﺑﻪ ﻋﻨﻮﺍﻥ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﻭ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﻮﺍﮐﺴﻴﺎﻝ ﮐﻮﺗﺎﻩ ﺩﺭ‬

‫ﻓﻮﺍﺻﻞ ‪ ٢ / ٥‬ﻣﺘﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺴﺘﮕﺎﻫﻬﺎﻱ ﮐﺎﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ ‪ .‬ﮐﺎﺑﻞ ﮐﻮﺍﮐﺴﻴﺎﻟﻲ ﮐﻪ ﺑﻪ‬ ‫ﻋﻨﻮﺍﻥ ﺳﺘﻮﻥ ﻓﻘﺮﺍﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ Ethernet Thick ،‬ﻭ ﻳﺎ ‪ Basee5١٠‬ﻧﺎﻣﻴﺪﻩ‬ ‫ﻣﻲ ﺷﻮﺩ ﮐﻪ ﺩﺭ ﺁﻥ ‪ ١٠‬ﺑﻪ ﺳﺮﻋﺖ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ ﺷﺒﮑﻪ ﺍﺷﺎﺭﻩ ﺩﺍﺷﺘﻪ ) ‪ ١٠‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬

‫ﺛﺎﻧﻴﻪ ( ﻭ ﻭﺍﮊﻩ ‪ Base‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺳﻴﺴﺘﻢ ‪ Base band‬ﺍﺳﺖ‪ .‬ﺩﺭ ﺳﻴﺴﺘﻢ ﻓﻮﻕ‪ ،‬ﺍﺯ ﺗﻤﺎﻣﻲ‬ ‫ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ‪ Broad band‬ﺑﻪ ﻣﻨﻈﻮﺭ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻫﻤﺰﻣﺎﻥ ‪ ،‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﺑﻪ ﮐﺎﻧﺎﻝ ﻫﺎﻱ ﻣﺘﻌﺪﺩﻱ ﺗﻘﺴﻴﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻋﺪﺩ ‪ ٥‬ﻧﻴﺰ ﺷﮑﻞ ﺧﻼﺻﻪ ﺷﺪﻩ ﺍﻱ ﺑﺮﺍﻱ ﻧﺸﺎﻥ ﺩﺍﺩﻥ ﺣﺪﺍﮐﺜﺮ ﻃﻮﻝ ﮐﺎﺑﻠﻲ ﺍﺳﺖ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ ) ﺩﺭ ﺍﻳﻦ ﻣﻮﺭﺩ ﺧﺎﺹ ‪ ٥٠٠‬ﻣﺘﺮ (‪.‬‬

‫‪381‬‬

‫ﻣﻮﺳﺴﻪ ‪ IEEE‬ﺩﺭ ﺳﺎﻝ ‪ ١٩٨٣‬ﻧﺴﺨﻪ ﺭﺳﻤﻲ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﺍﺗﺮﻧﺖ ﺭﺍ ﺑﺎ ﻧﺎﻡ ‪IEEE‬‬

‫‪ 802.3‬ﻭ ﺩﺭ ﺳﺎﻝ ‪ ، ١٩٨٥‬ﻧﺴﺨﻪ ﺷﻤﺎﺭﻩ ﺩﻭ ﺭﺍ ﺑﺎ ﻧﺎﻡ ‪ IEEE 802.3a‬ﺍﺭﺍﺋﻪ ﻧﻤﻮﺩ ‪ .‬ﺍﻳﻦ‬ ‫ﻧﺴﺨﻪ ﺑﺎ ﻧﺎﻡ ‪ Thin Ethernet‬ﻭ ﻳﺎ ‪ Base2١٠‬ﻣﻌﺮﻭﻑ ﮔﺮﺩﻳﺪ‪ ) .‬ﺣﺪﺍﮐﺜﺮ ﻃﻮﻝ ﮐﺎﺑﻞ‬

‫‪ ١٨٥‬ﻣﺘﺮ ﻣﻲ ﺑﺎﺷﺪ ﻭ ﻋﺪﺩ ‪ ٢‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺍﺳﺖ ﮐﻪ ﻃﻮﻝ ﮐﺎﺑﻞ ﻣﻲ ﺗﻮﺍﻧﺪ ﺗﺎ ﻣﺮﺯ‬ ‫‪ ٢٠٠‬ﻣﺘﺮ ﻧﻴﺰ ﺑﺮﺳﺪ(‬

‫ﺍﺯ ﺳﺎﻝ ‪ ١٩٨٣‬ﺗﺎﮐﻨﻮﻥ ‪ ،‬ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ﺍﺳﺖ ﮐﻪ ﻳﮑﻲ ﺍﺯ ﺍﻫﺪﺍﻑ ﻣﻬﻢ ﺁﻧﺎﻥ‬ ‫‪ ،‬ﺗﺎﻣﻴﻦ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻨﺎﺳﺐ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺍﺳﺖ ‪ .‬ﻣﺎ ﺍﻣﺮﻭﺯﻩ ﺷﺎﻫﺪ ﺭﺳﻴﺪﻥ ﺑﻪ ﻣﺮﺯ‬ ‫ﮔﻴﮕﺎﺑﻴﺖ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻣﻲ ﺑﺎﺷﻴﻢ‪.‬‬

‫ﮐﺎﺑﻞ ﻫﺎﻱ )‪Unshielded Twisted Pair) UTP‬‬

‫ﮐﺎﺑﻞ ‪ UTP‬ﻳﮑﻲ ﺍﺯ ﻣﺘﺪﺍﻭﻟـﺘﺮﻳﻦ ﮐﺎﺑﻞ ﻫﺎﻱ ﺍﺳـــﺘﻔﺎﺩﻩ ﺷﺪﻩ ﺩﺭ ﺷــﺒﮑﻪ ﻫﺎﻱ ﻣﺨـــﺎﺑﺮﺍﺗﻲ ﻭ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ ‪ .‬ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻋﻼﻭﻩ ﺑﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﺗﻠﻔﻦ‬ ‫ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ) ‪ .( CAT1‬ﺷﺶ ﻧﻮﻉ ﮐﺎﺑﻞ ‪ UTP‬ﻣﺘﻔﺎﻭﺕ ﻭﺟﻮﺩ ﺩﺍﺷﺘﻪ ﮐﻪ ﻣﻲ ﺗﻮﺍﻥ‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺷﺒﮑﻪ ﻭ ﺍﻫﺪﺍﻑ ﻣﻮﺭﺩ ﻧﻈﺮ ﺍﺯ ﺁﻧﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﮐﺎﺑﻞ ‪ ، CAT5‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ‬

‫ﻧﻮﻉ ﮐﺎﺑﻞ ‪ UTP‬ﻣﺤﺴﻮﺏ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻣﺸﺨﺼﻪ ﻫﺎﻱ ﮐﺎﺑﻞ ‪UTP‬‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺸﺨﺼﻪ ﻫﺎﻱ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ ، UTP‬ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ‪ ،‬ﻧﺼﺐ ﻭ ﺗﻮﺳﻌﻪ ﺳﺮﻳﻊ ﻭ ﺁﺳﺎﻥ‬ ‫ﺁﻧﺎﻥ ‪ ،‬ﻓﺮﺍﻫﻢ ﻣﻲ ﺁﻭﺭﺩ ‪ .‬ﺟﺪﻭﻝ ﺯﻳﺮ ﺍﻧﻮﺍﻉ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

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‫ﻣﻮﺍﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻗﺪﻳﻤﻲ ﺗﻠﻔﻦ ‪ ISDN ،‬ﻭ‬

‫ﺳﺮﻋﺖ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ‬

‫ﮔﺮﻭﻩ‬

‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﻳﮏ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫‪CAT1‬‬

‫ﻣﻮﺩﻡ‬ ‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﭼﻬﺎﺭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ‪CAT2‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪Ring Token‬‬

‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪ ring Token‬ﻭ ‪ BASE-١٠‬ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫‪CAT3‬‬

‫‪T‬‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪Ring Token‬‬

‫‪CAT4‬‬

‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﺷﺎﻧﺰﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬ ‫ﺛﺎﻧﻴﻪ‬ ‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﻳﮑﺼﺪ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬

‫ﺍﺗﺮﻧﺖ ) ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ‪ ،‬ﺍﺗﺮﻧﺖ‬

‫‪CAT5‬‬

‫ﺳﺮﻳﻊ ) ﻳﮑﺼﺪ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ﻭ ﺷﺒﮑﻪ ﺛﺎﻧﻴﻪ‬ ‫ﻫﺎﻱ ‪ ) Ring Token‬ﺷﺎﻧﺰﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬ ‫ﺛﺎﻧﻴﻪ (‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪Gigabit Ethernet‬‬

‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﻳﮑﻬﺰﺍﺭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬

‫‪CAT5e‬‬

‫ﺛﺎﻧﻴﻪ‬ ‫ﺷﺒﮑﻪ ﻫﺎﻱ ‪Gigabit Ethernet‬‬

‫ﺣﺪﺍﮐﺜﺮ ﺗﺎ ﻳﮑﻬﺰﺍﺭ ﻣﮕﺎﺑﻴﺖ ﺩﺭ‬

‫‪CAT6‬‬

‫ﺛﺎﻧﻴﻪ‬

‫ﺗﻮﺿﻴﺤﺎﺕ ‪:‬‬ ‫•‬

‫ﺗﻘﺴﻴﻢ ﺑﻨﺪﻱ ﻫﺮ ﻳﮏ ﺍﺯ ﮔﺮﻭﻩ ﻫﺎﻱ ﻓﻮﻕ ﺑﺮ ﺍﺳﺎﺱ ﻧﻮﻉ ﮐﺎﺑﻞ ﻣﺴﻲ ﻭ ‪ Jack‬ﺍﻧﺠﺎﻡ‬

‫•‬

‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ ، CAT1‬ﺑﻪ ﺩﻟﻴﻞ ﻋﺪﻡ ﺣﻤﺎﻳﺖ ﺗﺮﺍﻓﻴﮏ ﻣﻨﺎﺳﺐ‪ ،‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‬

‫ﺷﺪﻩ ﺍﺳﺖ‪.‬‬

‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﮔﺮﻭﻩ ‪ CAT4, CAT5 ,CAT2, CAT3‬ﻭ ‪ CAT6‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪.‬ﮐﺎﺑﻞ ﻫﺎﻱ ﻓﻮﻕ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﺎﻳﺖ ﺍﺯ ﺗﺮﺍﻓﻴﮏ ﺗﻠﻔﻦ ﻭ ﺷﺒﮑﻪ ﻫﺎﻱ‬ ‫ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫‪383‬‬

‫•‬

‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT2‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ Token Ring‬ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺳﺮﻋﺘﻲ ﺑﺎﻟﻎ‬

‫•‬

‫ﺑﺮﺍﻱ ﺷﺒﮑﻪ ﻫﺎﺋﻲ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ) ﻳﮑﺼﺪ ﻣﮕﺎ ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ( ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪CAT5‬‬

‫ﺑﺮ ‪ ٤‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

‫ﻭ ﺑﺮﺍﻱ ﺳﺮﻋﺖ ﺩﻩ ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT3‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫•‬

‫ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT3 ,CAT4‬ﻭ ‪ CAT5‬ﺍﺯ ﭼﻬﺎﺭ ﺯﻭﺝ ﮐﺎﺑﻞ ﻣﺴﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ‬

‫ﺍﺳﺖ‪ CAT5 .‬ﻧﺴﺒﺖ ﺑﻪ ‪ CAT3‬ﺩﺍﺭﺍﻱ ﺗﻌــﺪﺍﺩ ﺑﻴﺸــﺘﺮﻱ ﭘﻴــﭽﺶ ﺩﺭ ﻫﺮ ﺍﻳﻨـﭻ‬ ‫ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﺍﻳﻦ ﻧـﻮﻉ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎ ﺳﺮﻋﺖ ﻭ ﻣــﺴﺎﻓﺖ ﺑﻴــﺸﺘﺮ ﻱ ﺭﺍ ﺣﻤﺎﻳﺖ‬ ‫ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT3‬ﻭ ‪ CAT4‬ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ‪ Token Ring‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺣﺪﺍﮐﺜﺮ ﻣﺴﺎﻓﺖ ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ ، CAT3‬ﻳﮑﺼﺪ ﻣﺘﺮ ﺍﺳﺖ‪.‬‬

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‫ﺣﺪﺍﮐﺜﺮ ﻣﺴﺎﻓﺖ ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ ، CAT4‬ﺩﻭﻳﺴﺖ ﻣﺘﺮ ﺍﺳﺖ‪.‬‬

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‫ﮐﺎﺑﻞ ‪ CAT6‬ﺑﺎ ﻫﺪﻑ ﺍﺳﺘﻔﺎﺩﻩ ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ﺍﺗﺮﻧﺖ ﮔﻴﮕﺎﺑﻴﺖ ﻃﺮﺍﺣﻲ ﺷﺪﻩ ﺍﺳﺖ‪.‬‬ ‫ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺍﺳﺘﺎﻧﺪﺍﺭﺩﻫﺎﺋﻲ ﻧﻴﺰ ﻭﺟﻮﺩ ﺩﺍﺭﺩ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﮔﻴﮕﺎﺑﻴﺖ ﺑﺮ‬ ‫ﺭﻭﻱ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT5‬ﺭﺍ ﻓﺮﺍﻫﻢ ﻣﻲ ﻧﻤﺎﻳﺪ) ‪ .( CAT5e‬ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT6‬ﻣﺸﺎﺑﻪ‬

‫ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT5‬ﺑﻮﺩﻩ ﻭﻟﻲ ﺑﻴﻦ ‪ ٤‬ﺯﻭﺝ ﮐﺎﺑﻞ ﺁﻧﺎﻥ ﺍﺯ ﻳﮏ ﺟﺪﺍﮐﻨﻨﺪﻩ ﻓﻴﺰﻳﮑﻲ ﺑﻪ‬

‫ﻣﻨﻈﻮﺭ ﮐﺎﻫﺶ ﭘﺎﺭﺍﺯﻳﺖ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻭﻣﻐﻨﺎﻃﻴﺴﻲ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺳﺮﻋﺘﻲ ﺑﺎﻟﻎ ﺑﺮ ﻳﮑﻬﺰﺍﺭ‬ ‫ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﺭﺍ ﺍﺭﺍﺋﻪ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬ ‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﻳﮑﻲ ﺍﺯ ﻣﺤﻴﻂ ﻫﺎﻱ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺑﺎ ﺳﺮﻋﺖ ﺑﺎﻻ ﺍﺳﺖ‪ .‬ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺩﺭ‬

‫ﻣﻮﺍﺭﺩ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ‪ :‬ﺷﺒﮑﻪ ﻫﺎﻱ ﺗﻠﻔﻦ ﺷﻬﺮﻱ ﻭ ﺑﻴﻦ ﺷﻬﺮﻱ‪ ،‬ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻭ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻓﻴﺒﺮﻧﻮﺭﻱ ﺭﺷﺘﻪ ﺍﻱ ﺍﺯ ﺗﺎﺭﻫﺎﻱ ﺷﻴﺸﻪ ﺍﻱ ﺑﻮﺩﻩ ﮐﻪ ﻫﺮ ﻳﮏ ﺍﺯ‬ ‫ﺗﺎﺭﻫﺎ ﺩﺍﺭﺍﻱ ﺿﺨﺎﻣﺘﻲ ﻣﻌﺎﺩﻝ ﺗﺎﺭ ﻣﻮﻱ ﺍﻧﺴﺎﻥ ﺭﺍ ﺩﺍﺷﺘﻪ ﻭ ﺍﺯ ﺁﻧﺎﻥ ﺑﺮﺍﻱ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﺭ‬

‫ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

‫ﻣﺒﺎﻧﻲ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬

‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ‪ ،‬ﺭﺷﺘﻪ ﺍﻱ ﺍﺯ ﺗﺎﺭﻫﺎﻱ ﺑﺴﻴﺎﺭ ﻧﺎﺯﮎ ﺷﻴﺸﻪ ﺍﻱ ﺑﻮﺩﻩ ﮐﻪ ﻗﻄﺮ ﻫﺮ ﻳﮏ ﺍﺯ‬

‫ﺗﺎﺭﻫﺎ ﻧﻈﻴﺮ ﻗﻄﺮ ﻳﮏ ﺗﺎﺭ ﻣﻮﻱ ﺍﻧﺴﺎﻥ ﺍﺳﺖ‪ .‬ﺗﺎﺭﻫﺎﻱ ﻓﻮﻕ ﺩﺭ ﮐﻼﻑ ﻫﺎﺋﻲ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﻭ ﮐﺎﺑﻞ‬ ‫ﻫﺎﻱ ﻧﻮﺭﻱ ﺭﺍ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻭﺭﻧﺪ‪ .‬ﺍﺯ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺩﺭ‬ ‫ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﻳﮏ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺯ ﺳﻪ ﺑﺨﺶ ﻣﺘﻔﺎﻭﺕ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﻫﺴﺘﻪ )‪ . (Core‬ﻫﺴﺘﻪ ﻧﺎﺯﮎ ﺷﻴﺸﻪ ﺍﻱ ﺩﺭ ﻣﺮﮐﺰ ﻓﻴﺒﺮ ﮐﻪ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺩﺭ ﺁﻥ‬ ‫ﺣﺮﮐﺖ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺭﻭﮐﺶ )‪ . (Cladding‬ﺑﺨﺶ ﺧﺎﺭﺟﻲ ﻓﻴﺒﺮ ﺑﻮﺩﻩ ﮐﻪ ﺩﻭﺭﺗﺎﺩﻭﺭ ﻫﺴﺘﻪ ﺭﺍ ﺍﺣﺎﻃﻪ‬ ‫ﮐﺮﺩﻩ ﻭ ﺑﺎﻋﺚ ﺑﺮﮔﺸﺖ ﻧﻮﺭﻣﻨﻌﮑﺲ ﺷﺪﻩ ﺑﻪ ﻫﺴﺘﻪ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺑﺎﻓﺮ ﺭﻭﻳﻪ )‪ . (Coating Buffer‬ﺭﻭﮐﺶ ﭘﻼﺳﺘﻴﮑﻲ ﮐﻪ ﺑﺎﻋﺚ ﺣﻔﺎﻇﺖ ﻓﻴﺒﺮ ﺩﺭ‬ ‫ﻣﻘﺎﺑﻞ ﺭﻃﻮﺑﺖ ﻭ ﺳﺎﻳﺮ ﻣﻮﺍﺭﺩ ﺁﺳﻴﺐ ﭘﺬﻳﺮ‪ ،‬ﺍﺳﺖ‪.‬‬

‫ﺻﺪﻫﺎ ﻭ ﻫﺰﺍﺭﺍﻥ ﻧﻤﻮﻧﻪ ﺍﺯ ﺭﺷﺘﻪ ﻫﺎﻱ ﻧﻮﺭﻱ ﻓﻮﻕ ﺩﺭ ﺩﺳﺘﻪ ﻫﺎﺋﻲ ﺳﺎﺯﻣﺎﻧﺪﻫﻲ ﺷﺪﻩ ﻭ ﮐﺎﺑﻞ‬ ‫ﻫﺎﻱ ﻧﻮﺭﻱ ﺭﺍ ﺑﻮﺟﻮﺩ ﻣﻲ ﺁﻭﺭﻧﺪ‪ .‬ﻫﺮ ﻳﮏ ﺍﺯ ﮐﻼﻑ ﻫﺎﻱ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺗﻮﺳﻂ ﻳﮏ ﺭﻭﮐﺶ‬ ‫ﻫﺎﺋﻲ ﺑﺎ ﻧﺎﻡ ‪ Jacket‬ﻣﺤﺎﻓﻈﺖ ﻣﻲ ﮔﺮﺩﻧﺪ‪.‬‬ ‫ﻓﻴﺒﺮ ﻫﺎﻱ ﻧﻮﺭﻱ ﺩﺭ ﺩﻭ ﮔﺮﻭﻩ ﻋﻤﺪﻩ ﺍﺭﺍﺋﻪ ﻣﻲ ﮔﺮﺩﻧﺪ‪:‬‬ ‫•‬

‫ﻓﻴﺒﺮﻫﺎﻱ ﺗﮏ ﺣﺎﻟﺘﻪ )‪ . (Single-Mode‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺩﺭ ﻫﺮ‬ ‫ﻓﻴﺒﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ) ﻧﻈﻴﺮ ‪ :‬ﺗﻠﻔﻦ (‬

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‫ﻓﻴﺒﺮﻫﺎﻱ ﭼﻨﺪﺣﺎﻟﺘﻪ )‪ . (Multi-Mode‬ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﭼﻨﺪﻳﻦ ﺳﻴﮕﻨﺎﻝ ﺩﺭ ﻳﮏ‬ ‫ﻓﻴﺒﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ) ﻧﻈﻴﺮ ‪ :‬ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ(‬

‫ﻓﻴﺒﺮﻫﺎﻱ ﺗﮏ ﺣﺎﻟﺘﻪ ﺩﺍﺭﺍﻱ ﻳﮏ ﻫﺴﺘﻪ ﮐﻮﭼﮏ ) ﺗﻘﺮﻳﺒﺎ" ‪ ٩‬ﻣﻴﮑﺮﻭﻥ ﻗﻄﺮ ( ﺑﻮﺩﻩ ﻭ ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺍﺭﺳﺎﻝ ﻧﻮﺭ ﻟﻴﺰﺭﻱ ﻣﺎﺩﻭﻥ ﻗﺮﻣﺰ ) ﻃﻮﻝ ﻣﻮﺝ ﺍﺯ ‪ ١٣٠٠‬ﺗﺎ ‪ ١٥٥٠‬ﻧﺎﻧﻮﻣﺘﺮ( ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻓﻴﺒﺮﻫﺎﻱ‬ ‫ﭼﻨﺪ ﺣﺎﻟﺘﻪ ﺩﺍﺭﺍﻱ ﻫﺴﺘﻪ ﺑﺰﺭﮔﺘﺮ ) ﺗﻘﺮﻳﺒﺎ" ‪ ٦٢ / ٥‬ﻣﻴﮑﺮﻭﻥ ﻗﻄﺮ ( ﻭ ﻗﺎﺩﺭ ﺑﻪ ﺍﺭﺳﺎﻝ ﻧﻮﺭﻣﺎﺩﻭﻥ‬

‫ﻗﺮﻣﺰ ﺍﺯ ﻃﺮﻳﻖ ‪ LED‬ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬ ‫ﺍﺭﺳﺎﻝ ﻧﻮﺭ ﺩﺭ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬

‫ﻓﺮﺽ ﮐﻨﻴﺪ‪ ،‬ﻗﺼﺪ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﭼﺮﺍﻍ ﻗﻮﻩ ﻳﮏ ﺭﺍﻫﺮﻭﻱ ﺑﺰﺭﮒ ﻭ‬

‫ﻣﺴﺘﻘﻴﻢ ﺭﺍ ﺭﻭﺷﻦ ﻧﻤﺎﺋﻴﻢ‪ .‬ﻫﻤﺰﻣﺎﻥ ﺑﺎ ﺭﻭﺷﻦ ﻧﻤﻮﺩﻥ ﭼﺮﺍﻍ ﻗﻮﻩ‪ ،‬ﻧﻮﺭ ﻣﺮﺑﻮﻃﻪ ﺩﺭ ﻃﻮﻝ ﻣﺴﻴﺮ‬ ‫ﻣﺴﻔﻘﻴﻢ ﺭﺍﻫﺮﻭ ﺗﺎﺑﺎﻧﺪﻩ ﺷﺪﻩ ﻭ ﺁﻥ ﺭﺍ ﺭﻭﺷﻦ ﺧﻮﺍﻫﺪ ﮐﺮﺩ‪.‬‬ ‫‪386‬‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻋﺪﻡ ﻭﺟﻮﺩ ﺧﻢ ﻭ ﻳﺎ ﭘﻴﭻ ﺩﺭ ﺭﺍﻫﺮﻭ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺗﺎﺑﺶ ﻧﻮﺭ ﭼﺮﺍﻍ ﻗﻮﻩ‬

‫ﻣﺸﮑﻠﻲ ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﻭ ﭼﺮﺍﻍ ﻗﻮﻩ ﻣﻲ ﺗﻮﺍﻧﺪ ) ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺁﻥ ( ﻣﺤﺪﻭﺩﻩ ﻣﻮﺭﺩ ﻧﻈﺮ ﺭﺍ‬ ‫ﺭﻭﺷﻦ ﮐﺮﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺭﺍﻫﺮﻭﻱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﺧﻢ ﻭ ﻳﺎ ﭘﻴﭻ ﺑﺎﺷﺪ ‪ ،‬ﺑﺎ ﭼﻪ ﻣﺸﮑﻠﻲ ﺑﺮﺧﻮﺭﺩ‬ ‫ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ؟ ﺩﺭ ﺍﻳﻦ ﺣﺎﻟﺖ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﮏ ﺁﻳﻴﻨﻪ ﺩﺭ ﻣﺤﻞ ﭘﻴﭻ ﺭﺍﻫﺮﻭ ﺍﺳﺘﻔﺎﺩﻩ ﺗﺎ ﺑﺎﻋﺚ‬

‫ﺍﻧﻌﮑﺎﺱ ﻧﻮﺭ ﺍﺯ ﺯﺍﻭﻳﻪ ﻣﺮﺑﻮﻃﻪ ﮔﺮﺩﺩ‪.‬ﺩﺭ ﺻﻮﺭﺗﻴﮑﻪ ﺭﺍﻫﺮﻭﻱ ﻓﻮﻕ ﺩﺍﺭﺍﻱ ﭘﻴﭻ ﻫﺎﻱ ﺯﻳﺎﺩﻱ‬ ‫ﺑﺎﺷﺪ‪ ،‬ﭼﻪ ﮐﺎﺭ ﺑﺎﻳﺴﺖ ﮐﺮﺩ؟ ﺩﺭ ﭼﻨﻴﻦ ﺣﺎﻟﺘﻲ ﺩﺭ ﺗﻤﺎﻡ ﻃﻮﻝ ﻣﺴﻴﺮ ﺩﻳﻮﺍﺭ ﺭﺍﻫﺮﻭﻱ ﻣﻮﺭﺩ ﻧﻈﺮ‪،‬‬ ‫ﻣﻲ ﺑﺎﻳﺴﺖ ﺍﺯ ﺁﻳﻴﻨﻪ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪ .‬ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ ﻧﻮﺭ ﺗﺎﺑﺎﻧﺪﻩ ﺷﺪﻩ ﺗﻮﺳﻂ ﭼﺮﺍﻍ ﻗﻮﻩ )ﺑﺎ ﻳﮏ‬

‫ﺯﺍﻭﻳﻪ ﺧﺎﺹ( ﺍﺯ ﻧﻘﻄﻪ ﺍﻱ ﺑﻪ ﻧﻘﻄﻪ ﺍﻱ ﺩﻳﮕﺮ ﺣﺮﮐﺖ ﮐﺮﺩﻩ ) ﺟﻬﺶ ﮐﺮﺩﻩ ﻭ ﻃﻮﻝ ﻣﺴﻴﺮ‬ ‫ﺭﺍﻫﺮﻭ ﺭﺍ ﻃﻲ ﺧﻮﺍﻫﺪ ﮐﺮﺩ(‪ .‬ﻋﻤﻠﻴﺎﺕ ﻓﻮﻕ ﻣﺸﺎﺑﻪ ﺁﻧﭽﻴﺰﻱ ﺍﺳﺖ ﮐﻪ ﺩﺭ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﻧﺠﺎﻡ ﻣﻲ‬

‫ﮔﻴﺮﺩ‪.‬‬

‫ﻧﻮﺭ‪ ،‬ﺩﺭ ﮐﺎﺑﻞ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺯ ﻃﺮﻳﻖ ﻫﺴﺘﻪ )ﻧﻈﻴﺮ ﺭﺍﻫﺮﻭﻱ ﻣﺜﺎﻝ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ( ﻭ ﺗﻮﺳﻂ ﺟﻬﺶ‬ ‫ﻫﺎﻱ ﭘﻴﻮﺳﺘﻪ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺳﻄﺢ ﺁﺑﮑﺎﺭﻱ ﺷﺪﻩ ) ‪ ) (Cladding‬ﻣﺸﺎﺑﻪ ﺩﻳﻮﺍﺭﻫﺎﻱ ﺷﻴﺸﻪ ﺍﻱ‬ ‫ﻣﺜﺎﻝ ﺍﺭﺍﺋﻪ ﺷﺪﻩ ( ﺣﺮﮐﺖ ﻣﻲ ﮐﻨﺪ‪ ).‬ﻣﺠﻤﻮﻉ ﺍﻧﻌﮑﺎﺱ ﺩﺍﺧﻠﻲ (‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻨﮑﻪ ﺳﻄﺢ‬

‫ﺁﺑﮑﺎﺭﻱ ﺷﺪﻩ ‪ ،‬ﻗﺎﺩﺭ ﺑﻪ ﺟﺬﺏ ﻧﻮﺭ ﻣﻮﺟﻮﺩ ﺩﺭ ﻫﺴﺘﻪ ﻧﻤﻲ ﺑﺎﺷﺪ‪ ،‬ﻧﻮﺭ ﻗﺎﺩﺭ ﺑﻪ ﺣﺮﮐﺖ ﺩﺭ‬ ‫ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺑﺮﺧﻲ ﺍﺯ ﺳﻴﮕﻨﺎ ﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺑﺪﻟﻴﻞ ﻋﺪﻡ ﺧﻠﻮﺹ ﺷﻴﺸﻪ‬ ‫ﻣﻮﺟﻮﺩ ‪ ،‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﭼﺎﺭ ﻧﻮﻋﻲ ﺗﻀﻌﻴﻒ ﺩﺭ ﻃﻮﻝ ﻫﺴﺘﻪ ﮔﺮﺩﻧﺪ‪ .‬ﻣﻴﺰﺍﻥ ﺗﻀﻌﻴﻒ ﺳﻴﮕﻨﺎﻝ‬ ‫ﻧﻮﺭﻱ ﺑﻪ ﺩﺭﺟﻪ ﺧﻠﻮﺹ ﺷﻴﺸﻪ ﻭ ﻃﻮﻝ ﻣﻮﺝ ﻧﻮﺭ ﺍﻧﺘﻘﺎﻟﻲ ﺩﺍﺭﺩ‪ ) .‬ﻣﺜﻼ" ﻣﻮﺝ ﺑﺎ ﻃﻮﻝ ‪٨٥٠‬‬

‫ﻧﺎﻧﻮﻣﺘﺮ ﺑﻴﻦ ‪ ٦٠‬ﺗﺎ ‪ ٧٥‬ﺩﺭﺻﺪ ﺩﺭ ﻫﺮ ﮐﻴﻠﻮﻣﺘﺮ ‪ ،‬ﻣﻮﺝ ﺑﺎ ﻃﻮﻝ ‪ ١٣٠٠‬ﻧﺎﻧﻮﻣﺘﺮ ﺑﻴﻦ ‪ ٥٠‬ﺗﺎ ‪٦٠‬‬ ‫ﺩﺭﺻﺪ ﺩﺭ ﻫﺮ ﮐﻴﻠﻮﻣﺘﺮ ‪ ،‬ﻣﻮﺝ ﺑﺎ ﻃﻮﻝ ‪ ١٥٥٠‬ﻧﺎﻧﻮﻣﺘﺮ ﺑﻴﺶ ﺍﺯ ‪ ٥٠‬ﺩﺭﺻﺪ ﺩﺭ ﻫﺮ ﮐﻴﻠﻮﻣﺘﺮ(‬ ‫ﺳﻴﺴﺘﻢ ﺭﻟﻪ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬

‫ﺑﻤﻨﻈﻮﺭ ﺁﮔﺎﻫﻲ ﺍﺯ ﻧﺤﻮﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺩﺭ ﺳﻴﺴﺘﻢ ﻫﺎﻱ ﻣﺨﺎﺑﺮﺍﺗﻲ ‪ ،‬ﻣﺜﺎﻟﻲ ﺭﺍ ﺩﻧﺒﺎﻝ‬

‫ﺧﻮﺍﻫﻴﻢ ﮐﺮﺩ ﮐﻪ ﻣﺮﺑﻮﻁ ﺑﻪ ﻳﮏ ﻓﻴﻠﻢ ﺳﻴﻨﻤﺎﺋﻲ ﻭ ﻳﺎ ﻣﺴﺘﻨﺪ ﺩﺭ ﺭﺍﺑﻄﻪ ﺑﺎ ﺟﻨﮓ ﺟـــﻬﺎﻧﻲ ﺩﻭﻡ‬

‫ﺍﺳﺖ ‪ .‬ﺩﺭ ﻓﻴﻠﻢ ﻓﻮﻕ ﺩﻭ ﻧﺎﻭﮔﺎﻥ ﺩﺭﻳﺎﺋﻲ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﺳﻄﺢ ﺩﺭﻳﺎ ﺩﺭ ﺣﺎﻝ ﺣﺮﮐﺖ ﻣﻲ ﺑﺎﺷﻨﺪ ‪،‬‬ ‫ﻧﻴﺎﺯ ﺑﻪ ﺑﺮﻗﺮﺍﺭﻱ ﺍﺭﺗﺒﺎﻁ ﺑﺎ ﻳﮑﺪﻳﮕﺮ ﺩﺭ ﻳﮏ ﻭﺿﻌﻴﺖ ﮐﺎﻣﻼ" ﺑﺤﺮﺍﻧﻲ ﻭ ﺗﻮﻓﺎﻧﻲ ﺭﺍ ﺩﺍﺭﻧﺪ‪.‬‬ ‫‪387‬‬

‫ﻳـﮑﻲ ﺍﺯ ﻧﺎﻭﻫﺎ ﻗﺼﺪ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﻧﺎﻭ ﺩﻳﮕﺮ ﺭﺍ ﺩﺍﺭﺩ‪.‬ﮐﺎﭘﻴﺘﺎﻥ ﻧﺎﻭ ﻓﻮﻕ ﭘﻴﺎﻣﻲ‬

‫ﺑﺮﺍﻱ ﻳﮏ ﻣﻠﻮﺍﻥ ﮐﻪ ﺑﺮ ﺭﻭﻱ ﻋﺮﺷﻪ ﮐﺸﺘﻲ ﻣﺴﺘﻘﺮ ﺍﺳﺖ‪ ،‬ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﻣﻠﻮﺍﻥ ﻓﻮﻕ ﭘﻴﺎﻡ‬ ‫ﺩﺭﻳﺎﻓﺘﻲ ﺭﺍ ﺑﻪ ﻣﺠﻤﻮﻋﻪ ﺍﻱ ﺍﺯ ﮐﺪﻫﺎﻱ ﻣﻮﺭﺱ ) ﻧﻘﻄﻪ ﻭ ﻓﺎﺻﻠﻪ ( ﺗﺮﺟﻤﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ ﺍﺩﺍﻣﻪ‬ ‫ﻣﻠﻮﺍﻥ ﻣﻮﺭﺩ ﻧﻈﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﻧﻮﺭﺍﻓﮑﻦ ﺍﻗﺪﺍﻡ ﺑﻪ ﺍﺭﺳﺎﻝ ﭘﻴﺎﻡ ﺑﺮﺍﻱ ﻧﺎﻭ ﺩﻳﮕﺮ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﻳﮏ ﻣﻠﻮﺍﻥ ﺑﺮ ﺭﻭﻱ ﻋﺮﺷﻪ ﮐﺸﺘﻲ ﺩﻭﻡ‪ ،‬ﮐﺪﻫﺎﻱ ﻣﻮﺭﺱ ﺍﺭﺳﺎﻟﻲ ﺭﺍ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺩﺭ‬ ‫ﺍﺩﺍﻣﻪ ﻣﻠﻮﺍﻥ ﻓﻮﻕ ﮐﺪﻫﺎﻱ ﻓﻮﻕ ﺭﺍ ﺑﻪ ﻳﮏ ﺯﺑﺎﻥ ﺧﺎﺹ ) ﻣﺜﻼ" ﺍﻧﮕﻠﻴﺴﻲ ( ﺗﺒﺪﻳﻞ ﻭ ﺁﻧﻬﺎ ﺭﺍ‬ ‫ﺑﺮﺍﻱ ﮐﺎﭘﻴﺘﺎﻥ ﻧﺎﻭ ﺍﺭﺳﺎﻝ ﻣﻲ ﺩﺍﺭﺩ‪ .‬ﻓﺮﺽ ﮐﻨﻴﺪ ﻓﺎﺻﻠﻪ ﺩﻭ ﻧﺎﻭ ﻓﻮﻕ ﺍﺯ ﻳﮑﺪﻳﮕﺮ ﺑﺴﻴﺎﺭ ﺯﻳﺎﺩ )‬ ‫ﻫﺰﺍﺭﺍﻥ ﻣﺎﻳﻞ ( ﺑﻮﺩﻩ ﻭ ﺑﻤﻨﻈﻮﺭ ﺑﺮﻗﺮﺍﻱ ﺍﺭﺗﺒﺎﻁ ﺑﻴﻦ ﺁﻧﻬﺎ ﺍﺯ ﻳﮏ ﺳﻴﺴﺘﻢ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻣﺒﺘﻨﻲ ﺑﺮ‬

‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﮔﺮﺩﺩ‪.‬‬ ‫ﺳﻴﺴﺘﻢ ﺭﻟﻪ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺯ ﻋﻨﺎﺻﺮ ﺯﻳﺮ ﺗﺸﮑﻴﻞ ﺷﺪﻩ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﻓﺮﺳﺘﻨﺪﻩ ‪ .‬ﻣﺴﺌﻮﻝ ﺗﻮﻟﻴﺪ ﻭ ﺭﻣﺰﻧﮕﺎﺭﻱ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺍﺳﺖ‪.‬‬

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‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﻣﺪﻳﺮﻳﺖ ﺳﻴﮑﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺩﺭ ﻳﮏ ﻣﺴﺎﻓﺖ ﺭﺍ ﺑﺮﻋﻬﺪﻩ ﻣﻲ ﮔﻴﺮﺩ‪.‬‬

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‫ﺑﺎﺯﻳﺎﺏ ﻧﻮﺭﻱ ‪ .‬ﺑﻤﻨﻈﻮﺭ ﺗﻘﻮﻳﺖ ﺳﻴﮕﻨﺎ ﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺩﺭ ﻣﺴﺎﻓﺖ ﻫﺎﻱ ﻃﻮﻻﻧﻲ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

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‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻧﻮﺭﻱ ‪ .‬ﺳﻴﮕﻨﺎ ﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺭﻣﺰﮔﺸﺎﺋﻲ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬

‫ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﻪ ﺑﺮﺭﺳﻲ ﻫﺮ ﻳﮏ ﺍﺯ ﻋﻨﺎﺻﺮ ﻓﻮﻕ ﺧﻮﺍﻫﻴﻢ ﭘﺮﺩﺍﺧﺖ‪.‬‬

‫ﻓﺮﺳﺘﻨﺪﻩ‬

‫ﻭﻇﻴﻔﻪ ﻓﺮﺳﺘﻨﺪﻩ‪ ،‬ﻣﺸﺎﺑﻪ ﻧﻘﺶ ﻣﻠﻮﺍﻥ ﺑﺮ ﺭﻭﻱ ﻋﺮﺷﻪ ﮐﺸﺘﻲ ﻧﺎﻭ ﻓﺮﺳﺘﻨﺪﻩ ﭘﻴﺎﻡ ﺍﺳﺖ‪.‬‬

‫ﻓﺮﺳﺘﻨﺪﻩ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺭﺍ ﺩﺭﻳﺎﻓﺖ ﻭ ﺩﺳﺘﮕﺎﻩ ﻧﻮﺭﻱ ﺭﺍ ﺑﻤﻨﻈﻮﺭ ﺭﻭﺷﻦ ﻭ ﺧﺎﻣﻮﺵ‬ ‫ﺷﺪﻥ ﺩﺭ ﻳﮏ ﺩﻧﺒﺎﻟﻪ ﻣﻨﺎﺳﺐ ) ﺣﺮﮐﺖ ﻣﻨﺴﺠﻢ ( ﻫﺪﺍﻳﺖ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﻓﺮﺳﺘﻨﺪﻩ‪ ،‬ﺍﺯ ﻟﺤﺎﻅ‬ ‫ﻓﻴﺰﻳﮑﻲ ﺩﺭ ﻣﺠﺎﻭﺭﺕ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﻗﺮﺍﺭ ﺩﺍﺷﺘﻪ ﻭ ﻣﻤﮑﻦ ﺍﺳﺖ ﺩﺍﺭﺍﻱ ﻳﮏ ﻟﻨﺰ ﺑﻤﻨﻈﻮﺭ ﺗﻤﺮﮐﺰ‬

‫ﻧﻮﺭ ﺩﺭ ﻓﻴﺒﺮ ﺑﺎﺷﺪ‪ .‬ﻟﻴﺰﺭﻫﺎ ﺩﺍﺭﺍﻱ ﺗﻮﺍﻥ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﻱ ﻧﺴﺒﺖ ﺑﻪ ‪ LED‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﻗﻴﻤﺖ‬ ‫ﺁﻧﻬﺎ ﻧﻴﺰ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ‪ LED‬ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮﺍﺳﺖ‪ .‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻃﻮﻝ ﻣﻮﺝ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ‪،‬‬ ‫‪ ٨٥٠‬ﻧﺎﻧﻮﻣﺘﺮ‪ ١٣٠٠ ،‬ﻧﺎﻧﻮﻣﺘﺮ ﻭ ‪ ١٥٥٠‬ﻧﺎﻧﻮﻣﺘﺮ ﺍﺳﺖ‪.‬‬ ‫‪388‬‬

‫ﺑﺎﺯﻳﺎﺏ ) ﺗﻘﻮﻳﺖ ﮐﻨﻨﺪﻩ ( ﻧﻮﺭﻱ‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻗﺒﻼ" ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﺑﺮﺧﻲ ﺍﺯ ﺳﻴﮕﻨﺎﻝ ﻫﺎ ﺩﺭ ﻣﻮﺍﺭﺩﻳﮑﻪ ﻣﺴﺎﻓﺖ ﺍﺭﺳﺎﻝ‬

‫ﺍﻃﻼﻋﺎﺕ ﻃﻮﻻﻧﻲ ﺑﻮﺩﻩ ) ﺑﻴﺶ ﺍﺯ ﻳﮏ ﮐﻴﻠﻮﻣﺘﺮ ( ﻭ ﻳﺎ ﺍﺯ ﻣﻮﺍﺩ ﺧﺎﻟﺺ ﺑﺮﺍﻱ ﺗﻬﻴﻪ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬

‫) ﺷﻴﺸﻪ ( ﺍﺳﺘﻔﺎﺩﻩ ﻧﺸﺪﻩ ﺑﺎﺷﺪ‪ ،‬ﺗﻀﻌﻴﻒ ﻭ ﺍﺯ ﺑﻴﻦ ﺧﻮﺍﻫﻨﺪ ﺭﻓﺖ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ ﻭ‬

‫ﺑﻤﻨﻈﻮﺭ ﺗﻘﻮﻳﺖ ) ﺑﺎﻻ ﺑﺮﺩﻥ ( ﺳﻴﮕﻨﺎ ﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ﺗﻀﻌﻴﻒ ﺷﺪﻩ ﺍﺯ ﻳﮏ ﻳﺎ ﭼﻨﺪﻳﻦ " ﺗﻘﻮﻳﺖ‬ ‫ﮐﻨﻨﺪﻩ ﻧﻮﺭﻱ " ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺗﻘﻮﻳﺖ ﮐﻨﻨﺪﻩ ﻧﻮﺭﻱ ﺍﺯ ﻓﻴﺒﺮﻫﺎﻱ ﻧﻮﺭﻱ ﻣﺘﻌﻌﺪﺩ ﺑﻬﻤﺮﺍﻩ ﻳﮏ‬

‫ﺭﻭﮐﺶ ﺧﺎﺹ )‪ (doping‬ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﺑﺨﺶ ﺩﻭﭘﻴﻨﮓ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﻟﻴﺰﺭ ﭘﻤﭗ‬ ‫ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺯﻣﺎﻧﻴﮑﻪ ﺳﻴﮕﻨﺎﻝ ﺗﻀﻌﻴﻒ ﺷﺪﻩ ﺑﻪ ﺭﻭﮐﺶ ﺩﻭﭘﻴﻨﮕﻲ ﻣﻲ ﺭﺳﺪ‪ ،‬ﺍﻧﺮﮊﻱ ﻣﺎﺣﺼﻞ ﺍﺯ‬ ‫ﻟﻴﺰﺭ ﺑﺎﻋﺚ ﻣﻲ ﮔﺮﺩﺩ ﮐﻪ ﻣﻮﻟﮑﻮﻝ ﻫﺎﻱ ﺩﻭﭘﻴﻨﮓ ﺷﺪﻩ‪ ،‬ﺑﻪ ﻟﻴﺰﺭ ﺗﺒﺪﻳﻞ ﻣﻲ ﮔﺮﺩﻧﺪ‪ .‬ﻣﻮﻟﮑﻮﻝ‬

‫ﻫﺎﻱ ﺩﻭﭘﻴﻨﮓ ﺷﺪﻩ ﺩﺭ ﺍﺩﺍﻣﻪ ﺑﺎﻋﺚ ﺍﻧﻌﮑﺎﺱ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﻧﻮﺭﻱ ﺟﺪﻳﺪ ﻭ ﻗﻮﻳﺘﺮ ﺑﺎ ﻫﻤﺎﻥ‬ ‫ﺧﺼﺎﻳﺺ ﺳﻴﮕﻨﺎﻝ ﻭﺭﻭﺩﻱ ﺗﻀﻌﻴﻒ ﺷﺪﻩ ‪ ،‬ﺧﻮﺍﻫﻨﺪ ﺑﻮﺩ‪ ).‬ﺗﻘﻮﻳﺖ ﮐﻨﻨﺪﻩ ﻟﻴﺰﺭﻱ(‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻧﻮﺭﻱ‬

‫ﻭﻇﻴﻔﻪ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ‪ ،‬ﻣﺸﺎﺑﻪ ﻧﻘﺶ ﻣﻠﻮﺍﻥ ﺑﺮ ﺭﻭﻱ ﻋﺮﺷﻪ ﮐﺸﺘﻲ ﻧﺎﻭ ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﭘﻴﺎﻡ‬ ‫ﺍﺳﺖ‪ .‬ﺩﺳﺘﮕﺎﻩ ﻓﻮﻕ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺩﻳﺠﻴﺘﺎﻟﻲ ﻧﻮﺭﻱ ﺭﺍ ﺍﺧﺬ ﻭ ﭘﺲ ﺍﺯ ﺭﻣﺰﮔﺸﺎﺋﻲ ‪ ،‬ﺳﻴﮕﻨﺎ ﻝ‬ ‫ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﺭﺍ ﺑﺮﺍﻱ ﺳﺎﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﮐﻨﻨﺪﮔﺎﻥ ) ﮐﺎﻣﭙﻴﻮﺗﺮ ‪ ،‬ﺗﻠﻔﻦ ﻭ ‪ ( ...‬ﺍﺭﺳﺎﻝ ﻣﻲ ﻧﻤﺎﻳﺪ‪.‬‬ ‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﺑﻤﻨﻈﻮﺭ ﺗﺸﺨﻴﺺ ﻧﻮﺭ ﺍﺯ ﻳﮏ "ﻓﺘﻮﺳﻞ" ﻭ ﻳﺎ "ﻓﺘﻮﺩﻳﻮﺩ" ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮐﻨﺪ‪.‬‬

‫ﻣﺰﺍﻳﺎﻱ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‬

‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﺳﻴﻢ ﻫﺎﻱ ﻫﺎﻱ ﻣﺴﻲ ﺩﺍﺭﺍﻱ ﻣﺰﺍﻳﺎﻱ ﺯﻳﺮ ﺍﺳﺖ‪:‬‬ ‫•‬

‫ﺍﺭﺯﺍﻧﺘﺮ‪ .‬ﻫﺰﻳﻨﻪ ﭼﻨﺪﻳﻦ ﮐﻴﻠﻮﻣﺘﺮ ﮐﺎﺑﻞ ﻧﻮﺭﻱ ﻧﺴﺒﺖ ﺑﻪ ﺳﻴﻢ ﻫﺎﻱ ﻣﺴﻲ ﮐﻤﺘﺮ ﺍﺳﺖ‪.‬‬

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‫ﻧﺎﺯﮎ ﺗﺮ‪ .‬ﻗﻄﺮ ﻓﻴﺒﺮﻫﺎﻱ ﻧﻮﺭﻱ ﺑﻤﺮﺍﺗﺐ ﮐﻤﺘﺮ ﺍﺯ ﺳﻴﻢ ﻫﺎﻱ ﻣﺴﻲ ﺍﺳﺖ‪.‬‬

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‫ﻇﺮﻓﻴﺖ ﺑﺎﻻ ‪ .‬ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﻤﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺯ‬

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‫ﺗﻀﻌﻴﻒ ﻧﺎﭼﻴﺰ‪ .‬ﺗﻀﻌﻴﻒ ﺳﻴﮕﻨﺎﻝ ﺩﺭ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﻤﺮﺍﺗﺐ ﮐﻤﺘﺮ ﺍﺯ ﺳﻴﻢ ﻣﺴﻲ ﺍﺳﺖ‪.‬‬

‫ﺳﻴﻢ ﻣﺴﻲ ﺍﺳﺖ‪.‬‬

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‫ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﻮﺭﻱ ‪ .‬ﺑﺮﺧﻼﻑ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﺩﺭ ﻳﮏ ﺳﻴﻢ ﻣﺴﻲ ‪ ،‬ﺳﻴﮕﻨﺎ ﻝ‬

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‫ﻣﺼﺮﻑ ﺑﺮﻕ ﭘﺎﻳﻴﻦ ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺳﻴﮕﻨﺎﻝ ﻫﺎ ﺩﺭ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﮐﻤﺘﺮ ﺿﻌﻴﻒ ﻣﻲ ﮔﺮﺩﻧﺪ‪،‬‬

‫ﻫﺎ ﻱ ﻧﻮﺭﻱ ﺩﺭ ﻳﮏ ﻓﻴﺒﺮ ﺗﺎﺛﻴﺮﻱ ﺑﺮ ﻓﻴﺒﺮ ﺩﻳﮕﺮ ﻧﺨﻮﺍﻫﻨﺪ ﺩﺍﺷﺖ‪.‬‬

‫ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻓﺮﺳﺘﻨﺪﻩ ﻫﺎﺋﻲ ﺑﺎ ﻣﻴﺰﺍﻥ ﺑﺮﻕ ﻣﺼﺮﻓﻲ ﭘﺎﻳﻴﻦ ﻧﺴﺒﺖ ﺑﻪ ﻓﺮﺳﺘﻨﺪﻩ‬ ‫ﻫﺎﻱ ﺍﻟﮑﺘﺮﻳﮑﻲ ﮐﻪ ﺍﺯ ﻭﻟﺘﺎﮊ ﺑﺎﻻﺋﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﮐﺮﺩ‪.‬‬

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‫ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺩﻳﺠﻴﺘﺎﻝ ‪ .‬ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﻣﻨﺎﺳﺐ ﺑﻤﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺍﻃﻼﻋﺎﺕ ﺩﻳﺠﻴﺘﺎﻟﻲ ﺍﺳﺖ‪.‬‬

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‫ﻏﻴﺮ ﺍﺷﺘﻌﺎﻝ ﺯﺍ ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻋﺪﻡ ﻭﺟﻮﺩ ﺍﻟﮑﺘﺮﻳﺴﻴﺘﻪ‪ ،‬ﺍﻣﮑﺎﻥ ﺑﺮﻭﺯ ﺁﺗﺶ ﺳﻮﺯﻱ ﻭﺟﻮﺩ‬

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‫ﺳﺒﮏ ﻭﺯﻥ ‪ .‬ﻭﺯﻥ ﻳﮏ ﮐﺎﺑﻞ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺑﻤﺮﺍﺗﺐ ﮐﻤﺘﺮ ﺍﺯ ﮐﺎﺑﻞ ﻣﺴﻲ )ﻗﺎﺑﻞ ﻣﻘﺎﻳﺴﻪ(‬

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‫ﺍﻧﻌﻄﺎﻑ ﭘﺬﻳﺮ ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻧﻌﻈﺎﻑ ﭘﺬﻳﺮﻱ ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﻭ ﻗﺎﺑﻠﻴﺖ ﺍﺭﺳﺎﻝ ﻭ ﺩﺭﻳﺎﻓﺖ‬

‫ﻧﺨﻮﺍﻫﺪ ﺩﺍﺷﺖ‪.‬‬ ‫ﺍﺳﺖ‪.‬‬

‫ﻧﻮﺭ ﺍﺯ ﺁﻧﺎﻥ‪ ،‬ﺩﺭ ﻣﻮﺍﺭﺩ ﻣﺘﻔﺎﻭﺕ ﻧﻈﻴﺮ ﺩﻭﺭﺑﻴﻦ ﻫﺎﻱ ﺩﻳﺠﻴﺘﺎﻝ ﺑﺎ ﻣﻮﺍﺭﺩ ﮐﺎﺭﺑﺮﺩﻱ ﺧﺎﺹ‬

‫ﻣﺎﻧﻨﺪ ‪ :‬ﻋﮑﺲ ﺑﺮﺩﺍﺭﻱ ﭘﺰﺷﮑﻲ‪ ،‬ﻟﻮﻟﻪ ﮐﺸﻲ ﻭ ‪...‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﺰﺍﻳﺎﻱ ﻓﺮﺍﻭﺍﻥ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‪ ،‬ﺍﻣﺮﻭﺯﻩ ﺍﺯ ﺍﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ﻫﺎ ﺩﺭ ﻣﻮﺍﺭﺩ ﻣﺘﻔﺎﻭﺗﻲ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﺷﻮﺩ‪ .‬ﺍﮐﺜﺮ ﺷﺒﮑﻪ ﻫﺎﻱ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﻭ ﻳﺎ ﻣﺨﺎﺑﺮﺍﺕ ﺍﺯﺭﺍﻩ ﺩﻭﺭ ﺩﺭ ﻣﻘﻴﺎﺱ ﻭﺳﻴﻌﻲ ﺍﺯ‬ ‫ﻓﻴﺒﺮ ﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪.‬‬

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‫ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ‪X-Over‬‬ ‫ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﺮﺍﺱ ‪ CAT5 UTP‬ﮐﻪ ﺍﺯ ﺁﻧﺎﻥ ﺑﺎ ﻧﺎﻡ ‪ X-over‬ﻧﻴﺰ ﻧﺎﻡ ﺑﺮﺩﻩ ﻣﻲ ﺷﻮﺩ‪،‬‬

‫ﻳﮑﻲ ﺍﺯ ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﮐﺎﺑﻞ ﻫﺎﻱ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﭘﺲ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ Straight‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺑﺎ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ﻓﻮﻕ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺑﺪﻭﻥ ﻧﻴﺎﺯ ﺑﻪ ﻳﮏ ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﺑﻪ‬ ‫ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﻮﺩ‪ .‬ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺍﻳﻦ ﮐﻪ ﻫﺎﺏ ﻋﻤﻠﻴﺎﺕ ‪ X-over‬ﺭﺍ ﺑﻪ ﺻﻮﺭﺕ ﺩﺍﺧﻠﻲ‬ ‫ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﺪ‪ ،‬ﺩﺭ ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺭﺍ ﺑﻪ ﻳﮏ ﻫﺎﺏ ﻣﺘﺼﻞ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﺻﺮﻓﺎ" ﺑﻪ ﻳﮏ‬

‫ﮐﺎﺑﻞ ‪ Straight‬ﻧﻴﺎﺯ ﻣﻲ ﺑﺎﺷﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﺍﺗﺼﺎﻝ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺭﺍ‬ ‫ﺑﺪﻭﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﻫﺎﺏ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ ﻋﻤﻠﻴﺎﺕ ‪ X-over‬ﺭﺍ ﺑﻪ ﺻﻮﺭﺕ‬ ‫ﺩﺳﺘﻲ ﺍﻧﺠﺎﻡ ﺩﺍﺩ ﻭ ﮐﺎﺑﻞ ﻣﺨﺘﺺ ﺁﻥ ﺭﺍ ﺍﻳﺠﺎﺩ ﻧﻤﻮﺩ‪.‬‬ ‫ﭼﺮﺍ ﺑﻪ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ X-over‬ﻧﻴﺎﺯ ﺩﺍﺭﻳﻢ ؟‬

‫ﺩﺭ ﺯﻣﺎﻥ ﻣﺒﺎﺩﻟﻪ ﺩﺍﺩﻩ ﺑﻴﻦ ﺩﻭ ﺩﺳﺘﮕﺎﻩ ) ﻣﺜﻼ" ﮐﺎﻣﭙﻴﻮﺗﺮ (‪ ،‬ﻳﮑﻲ ﺍﺯ ﺁﻧﺎﻥ ﺑﻪ ﻋﻨﻮﺍﻥ‬

‫ﺩﺭﻳﺎﻓﺖ ﮐﻨﻨﺪﻩ ﻭ ﺩﻳﮕﺮﻱ ﺑﻪ ﻋﻨﻮﺍﻥ ﻓﺮﺳﺘﻨﺪﻩ ﺍﻳﻔﺎﻱ ﻭﻇﻴﻔﻪ ﻣﻲ ﻧﻤﺎﻳﺪ‪ .‬ﺗﻤﺎﻣﻲ ﻋﻤﻠﻴﺎﺕ ﺍﺭﺳﺎﻝ‬ ‫ﺩﺍﺩﻩ ﺍﺯ ﻃﺮﻳﻖ ﮐﺎﺑﻞ ﻫﺎﻱ ﺷﺒﮑﻪ ﺍﻧﺠﺎﻡ ﻣﻲ ﺷﻮﺩ ‪.‬ﻳﮏ ﮐﺎﺑﻞ ﺷﺒﮑﻪ ﺍﺯ ﭼﻨﺪﻳﻦ ﺭﺷﺘﻪ ﺳﻴﻢ ﺩﻳﮕﺮ‬

‫ﺗﺸﮑﻴﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺍﺯ ﺑﺮﺧﻲ ﺭﺷﺘﻪ ﺳﻴﻢ ﻫﺎ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺭﺳﺎﻝ ﺩﺍﺩﻩ ﻭ ﺍﺯ ﺑﺮﺧﻲ ﺩﻳﮕﺮ ﺑﻪ ﻣﻨﻈﻮﺭ‬

‫ﺩﺭﻳﺎﻓﺖ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﺷﻮﺩ‪ .‬ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻳﮏ ﮐﺎﺑﻞ ‪ X-over‬ﺍﺯ ﺭﻭﻳﮑﺮﺩ ﻓﻮﻕ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﺷﺪﻩ ﻭ ‪ ) TX‬ﺍﺭﺳﺎﻝ ( ﻳﮏ ﺳﻤﺖ ﺑﻪ ‪) RX‬ﺩﺭﻳﺎﻓﺖ ( ﺳﻤﺖ ﺩﻳﮕﺮ‪ ،‬ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺷﮑﻞ‬ ‫ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﻧﺠﺎﻡ ﺍﻳﻦ ﻋﻤﻠﻴﺎﺕ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ ‪:‬‬

‫ﺍﺗﺼﺎﻝ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ‬ ‫‪X-over‬‬

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‫ﮐﺎﺑﻞ ‪CAT5 X-over‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ﻫﺎﻱ ﮐﺮﺍﺱ ‪ CAT5‬ﺻﺮﻓﺎ" ﺍﺯ ﻳﮏ ﺭﻭﺵ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﻗﺒﻼ" ﺍﺷﺎﺭﻩ ﮔﺮﺩﻳﺪ‪ ،‬ﻳﮏ ﮐﺎﺑﻞ ‪ X-over‬ﭘﻴﻦ ‪ TX‬ﻳﮏ ﺳﻤﺖ ﺭﺍ ﺑﻪ ﭘﻴﻦ ‪RX‬‬

‫ﺳﻤﺖ ﺩﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﻧﻤﺎﻳﺪ) ﻭ ﺑﺮﻋﮑﺲ(‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﻳﮏ ﮐﺎﺑﻞ ‪CAT5‬‬

‫ﻣﻌﻤﻮﻟﻲ ‪ X-over‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪.‬‬ ‫ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﻳﮏ ﮐﺎﺑﻞ ‪CAT5 X-‬‬ ‫‪. over‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺷﮑﻞ ﻓﻮﻕ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﮔﺮﺩﺩ ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ X-over‬ﺻﺮﻓﺎ" ﺍﺯ ﭘﻴﻦ ﻫﺎﻱ‬

‫ﺷﻤﺎﺭﻩ ﻳﮏ‪ ،‬ﺩﻭ‪ ،‬ﺳﻪ ﻭ ﺷﺶ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﻴﻦ ﻫﺎﻱ ﻳﮏ ﻭ ﺩﻭ ﺑﻤﻨﺰﻟﻪ ﻳﮏ ﺯﻭﺝ ﺑﻮﺩﻩ ﻭ‬ ‫ﭘﻴﻦ ﻫﺎﻱ ﺳﻪ ﻭ ﺷﺶ ﺯﻭﺝ ﺩﻳﮕﺮ ﺭﺍ ﺗﺸﮑﻴﻞ ﻣﻲ ﺩﻫﻨﺪ‪ .‬ﺍﺯ ﭘﻴﻦ ﻫﺎﻱ ﭼﻬﺎﺭ‪ ،‬ﭘﻨﺞ ‪ ،‬ﻫﻔﺖ ﻭ‬ ‫ﻫﺸﺖ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﮔﺮﺩﺩ ‪ ) .‬ﺻﺮﻓﺎ" ﺍﺯ ﭼﻬﺎﺭ ﭘﻴﻦ ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﻳﮏ ﮐﺎﺑﻞ ‪ ، X-over‬ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ (‪.‬‬ ‫ﻣﻮﺍﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪X-over‬‬

‫ﺍﺯ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ X-over‬ﺻﺮﻓﺎ" ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﺩﻭ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻲ ﺷﻮﺩ ﻭ‬

‫ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﺁﻧﺎﻥ ﺩﺭ ﺩﺳﺘﮕﺎﻩ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﻧﻈﻴﺮ ﺳﻮﺋﻴﭻ ﻭ ﻳﺎ ﻫﺎﺏ ﻧﻴﺰ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺩﺭ‬ ‫ﺻﻮﺭﺗﻲ ﮐﻪ ﻗﺼﺪ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﻢ ﺩﻭ ﻫﺎﺏ ﺭﺍ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﻣﻌﻤﻮﻻ" ﺍﺯ ﭘﻮﺭﺕ‬ ‫‪ uplink‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﭘﻮﺭﺕ ﻓﻮﻕ ‪ ،‬ﺑﺨﺶ ﻫﺎﻱ ‪ tx‬ﻭ ‪ rx‬ﺭﺍ ﮐﺮﺍﺱ ﻧﻤﻲ ﻧﻤﺎﻳﺪ‪.‬‬

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‫ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺗﺼﺎﻝ ﺩﻭ ﻫﺎﺏ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ‪ Straight‬ﻭ ﺍﺯ ﻃﺮﻳﻖ‬ ‫ﭘﻮﺭﺕ ‪ Uplink‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫ﺍﺗﺼﺎﻝ ﺩﻭ ﻫﺎﺏ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ‪ Uplink‬ﻭ‬ ‫ﻳﮏ ﮐﺎﺑﻞ ‪Straight‬‬

‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻭﺟﻮﺩ ﭘﻮﺭﺕ ‪ ، uplink‬ﻧﻴﺎﺯﻱ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ‪ x-over‬ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﻣﮑﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ‪ uplink‬ﻭﺟﻮﺩ ﻧﺪﺍﺷﺘﻪ ﺑﺎﺷﺪ ﻭ ﺑﺨﻮﺍﻫﻴﻢ ﺩﻭ ﻫﺎﺏ ﺭﺍ‬ ‫ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻫﺎﻱ ﻣﻌﻤﻮﻟﻲ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻧﻤﺎﺋﻴﻢ‪ ،‬ﻣﻲ ﺗﻮﺍﻥ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ‪X-over‬‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪ .‬ﺷﮑﻞ ﺯﻳﺮ ﻧﺤﻮﻩ ﺍﺗﺼﺎﻝ ﺩﻭ ﻫﺎﺏ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻳﮏ ﮐﺎﺑﻞ ‪X-over‬‬ ‫ﺭﺍ ﻭ ﺑﺪﻭﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ‪ Uplink‬ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬

‫ﺍﺗﺼﺎﻝ ﺩﻭ ﻫﺎﺏ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ﻣﻌﻤﻮﻟﻲ‬ ‫ﻭ ﻳﮏ ﮐﺎﺑﻞ ‪X-over‬‬

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‫ﺷﮑﻞ ﺯﻳﺮ ﺗﻔﺎﻭﺕ ﻣﻮﺟﻮﺩ ﺑﻴﻦ ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﻳﮏ ﮐﺎﺑﻞ ‪ Straight‬ﻭ ‪ X-over‬ﺭﺍ ﻧﺸﺎﻥ‬

‫ﻣﻲ ﺩﻫﺪ ‪:‬‬

‫ﺗﻔﺎﻭﺕ ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﺑﻴﻦ ﮐﺎﺑﻞ‬ ‫‪ Straight‬ﻭ ‪X-over‬‬

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‫ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ‪Straight‬‬ ‫ﮐﺎﺑﻞ ﮐﺸﻲ ﺷﺒﮑﻪ ﻳﮑﻲ ﺍﺯ ﻣﺮﺍﺣﻞ ﻣﻬﻢ ﺩﺭ ﺯﻣﺎﻥ ﭘﻴﺎﺩﻩ ﺳﺎﺯﻱ ﻳﮏ ﺷﺒﮑﻪ ﮐﺎﻣﭙﻴﻮﺗﺮﻱ ﺍﺳﺖ‬ ‫ﮐﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺑﺎ ﺩﻗﺖ‪،‬ﻇﺮﺍﻓﺖ ﺧﺎﺹ ﻭ ﭘﺎﻳﺒﻨﺪﻱ ﺑﻪ ﺍﺻﻮﻝ ﮐﺎﺑﻞ ﮐﺸﻲ ﺳﺎﺧﺖ ﻳﺎﻓﺘﻪ‪ ،‬ﺍﻧﺠﺎﻡ‬ ‫ﺷﻮﺩ‪ .‬ﺑﺮﺍﻱ ﺍﻳﺠﺎﺩ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺍﺯ ﺗﺠﻬﻴﺰﺍﺕ ﺯﻳﺮ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪:‬‬ ‫ﺗﺠﻬﻴﺰﺍﺕ ﻣﻮﺭﺩ ﻧﻴﺎﺯ‬

‫ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ ‪RJ-‬‬

‫ﮐﺎﺑﻞ ‪UTP‬‬

‫‪45‬‬ ‫ﺁﭼﺎﺭ ﭘﺮﺱ ‪RJ-45‬ﺳﻴﻢ ﻟﺨﺖ ﮐﻦ‬

‫ﻳﮑﻲ ﺍﺯ ﻋﻮﺍﻣﻞ ﺗﺎﺛﻴﺮ ﮔﺬﺍﺭ ﺩﺭ ﭘﺸﺘﻴﺒﺎﻧﻲ ﻭ ﻧﮕﻬﺪﺍﺭﻱ ﻳﮏ ﺷﺒﮑﻪ‪ ،‬ﻧﺤﻮﻩ ﮐﺎﺑﻞ ﮐﺸﻲ ﺁﻥ ﺍﺳﺖ‪.‬‬ ‫ﺑﺎ ﺭﻋﺎﻳﺖ ﺍﺻﻮﻝ ﮐﺎﺑﻞ ﮐﺸﻲ ﺳﺎﺧﺘﻴﺎﻓﺘﻪ‪ ،‬ﺩﺭ ﺻﻮﺭﺕ ﺑﺮﻭﺯ ﺍﺷﮑﺎﻝ ﺩﺭ ﺷﺒﮑﻪ‪ ،‬ﺗﺸﺨﻴﺺ ﻭ‬ ‫ﺍﺷﮑﺎﻝ ﺯﺩﺍﺋﻲ ﺁﻥ ﺑﺎ ﺳﺮﻋﺘﻲ ﻣﻨﺎﺳﺒﻲ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺷﺪ‪.‬‬ ‫ﻣﺮﺍﺣﻞ ﺍﻳﺠﺎﺩ ﻳﮏ ﮐﺎﺑﻞ ‪ :‬ﺑﺪﻭﻥ ﻫﻴﭽﮕﻮﻧﻪ ﺗﻮﺿﻴﺢ ﺍﺿﺎﻓﻪ !‬ ‫ﻣﺮﺣﻠﻪ ﺩﻭﻡ‬

‫ﻣﺮﺣﻠﻪ ﺍﻭﻝ‬

‫ﻣﺮﺣﻠﻪ ﭼﻬﺎﺭﻡ‬

‫ﻣﺮﺣﻠﻪ ﺳﻮﻡ‬

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‫ﻣﺮﺣﻠﻪ ﭘﻨﺠﻢ‬

‫ﻣﺪﻝ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺕ ﮐﺎﺑﻞ ﮐﺸﻲ ﮐﺎﺑﻞ ﻫﺎﻱ ‪UTP‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﺎﺑﻞ ﮐﺸﻲ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺍﺯ ﺩﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻣﺘﻔﺎﻭﺕ ‪ T-568A‬ﻭ‬

‫‪ T-568B‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺩﻭ ﻣﺪﻝ ﻓﻮﻕ ﻳﮑﺴﺎﻥ ﺑﻮﺩﻩ ﻭ ﺗﻨﻬﺎ ﺗﻔﺎﻭﺕ‬ ‫ﻣﻮﺟﻮﺩ ﺑﻪ ﺭﻧﮓ ﺯﻭﺝ ﻫﺎﺋﻲ ﺍﺳﺖ ﮐﻪ ﺑﻪ ﻳﮑﺪﻳﮕﺮ ﻣﺘﺼﻞ ﻣﻲ ﺷﻮﻧﺪ‪ .‬ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺍﺯ‬ ‫ﮐﺎﻧﮑﺘﻮﺭﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻭ ﭼﻬﺎﺭ ﺯﻭﺝ ﺳﻴﻢ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪:‬‬ ‫•‬

‫ﺯﻭﺝ ﺍﻭﻝ ‪ :‬ﺁﺑﻲ ﻭ ﺳﻔﻴﺪ‪ /‬ﺁﺑﻲ‬

‫•‬

‫ﺯﻭﺝ ﺩﻭﻡ ‪ :‬ﻧﺎﺭﻧﺠﻲ ﻭ ﺳﻔﻴﺪ ‪/‬ﻧﺎﺭﻧﺠﻲ‬

‫•‬

‫ﺯﻭﺝ ﺳﻮﻡ ‪ :‬ﺳﺒﺰ ﻭ ﺳﻔﻴﺪ‪ /‬ﺳﺒﺰ‬

‫•‬

‫ﺯﻭﺝ ﭼﻬﺎﺭﻡ ‪ :‬ﻗﻬﻮﻩ ﺍﻱ ﻭ ﺳﻔﻴﺪ ‪ /‬ﻗﻬﻮﻩ ﺍﻱ‬

‫ﺩﺭ ﺷﺒﮑﻪ ﻫﺎﻱ ‪ Mbit ١٠/١٠٠‬ﺍﺯ ﺯﻭﺝ ﻫﺎﻱ ﺩﻭ ﻭ ﺳﻪ ﺍﺳﺘﻔﺎﺩﻩ ﺷﺪﻩ ﻭ ﺯﻭﺝ ﻫﺎﻱ ﻳــﮏ ﻭ‬

‫ﭼﻬﺎﺭ ﺭﺯﻭ ﺷﺪﻩ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺷـــﺒﮑﻪ ﻫﺎﻱ ﮔﻴــﮕﺎﺍﺗﺮﻧﺖ ﺍﺯ ﺗــﻤﺎﻣﻲ ﭼﻬﺎﺭ ﺯﻭﺝ ﺍﺳـﺘﻔﺎﺩﻩ‬

‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT5‬ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﻧﻮﻉ ﮐﺎﺑﻞ ‪ UTP‬ﺑﻮﺩﻩ ﮐﻪ ﺩﺍﺭﺍﻱ ﺍﻧﻌﻄﺎﻑ‬ ‫ﻣﻨﺎﺳﺐ ﺑﻮﺩﻩ ﻭ ﻧﺼﺐ ﺁﻧﺎﻥ ﺑﺴﺎﺩﮔﻲ ﺍﻧﺠﺎﻡ ﻣﻲ ﺷﻮﺩ‪.‬‬

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‫ﺍﻳﺠﺎﺩ ﻳﮏ ﮐﺎﺑﻞ ‪ UTP‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﮐﺎﻣﭙﻴﻮﺗﺮ ﺑﻪ ﻫﺎﺏ ) ﻣﻌﺮﻭﻑ ﺑﻪ ﮐﺎﺑﻞ ﻫﺎﻱ‬ ‫‪( Straight‬‬

‫ﺍﺗﺮﻧﺖ ﻋﻤﻮﻣﺎ" ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻫﺸﺖ ﮐﺎﺑﻞ ﻫﺎﺩﻱ ﺑﻪ ﻫﻤﺮﺍﻩ ﻫﺸﺖ ﭘﻴﻦ ﻣﺎﮊﻭﻻﺭ‬

‫‪ ، plugs/jacks‬ﺩﺍﺩﻩ ﺭﺍ ﺣﻤﻞ ﻣﻲ ﮐﻨﺪ‪.‬‬

‫ﮐﺎﻧﮑﺘﻮﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ‪ RJ-45 ،‬ﻧﺎﻣﻴﺪﻩ ﺷﺪﻩ ﻭ ﻣﺸﺎﺑﻪ ﮐﺎﻧﮑﺘﻮﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ RJ-11‬ﺍﺳﺖ ﮐﻪ ﺩﺭ‬ ‫ﺗﻠﻔﻦ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﻳﮏ ﺭﺷﺘﻪ ﮐﺎﺑﻞ ‪ CAT5‬ﺷﺎﻣﻞ ﭼﻬﺎﺭ ﺯﻭﺝ ﺳﻴﻢ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﺍﺳﺖ ﮐﻪ‬ ‫ﻫﺮ ﺯﻭﺝ ﺩﺍﺭﺍﻱ ﺩﻭ ﺭﺷﺘﻪ ﺳﻴﻢ ﺑﺎ ﺭﻧﮓ ﻫﺎﺋﻲ ﺧﺎﺹ ﺍﺳﺖ‪) .‬ﻳﮏ ﺭﺷﺘﻪ ﺭﻧﮕﻲ ﻭ ﻳﮏ ﺭﺷﺘﻪ‬ ‫ﺳﻔﻴﺪ ﺑﺎ ﻧﻮﺍﺭﻱ ﺑﻪ ﺭﻧﮓ ﺭﺷﺘﻪ ﺯﻭﺝ ﻣﺮﺑﻮﻁ(‪ .‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺗﺴﻬﻴﻞ ﺩﺭ ﺍﻣﺮ ﻧﮕﻬﺪﺍﺭﻱ‪ ،‬ﻣﻲ ﺑﺎﻳﺴﺖ‬

‫ﺑﻪ ﺍﻧﺪﺍﺯﻩ ﺿﺮﻭﺭﻱ ﺳﻴﻢ ﻫﺎﻱ ﺑﻬﻢ ﺗﺎﺑﻴﺪﻩ ﺭﺍ ﺍﺯ ﺣﺎﻟﺖ ﭘﻴﭽﺶ ﺧﺎﺭﺝ ﻧﻤﻮﺩ )ﻣﺜﻼ" ﺣﺪﻭﺩ ﻳﮏ‬ ‫ﺳﺎﻧﺘﻴﻤﺘﺮ(‪ .‬ﺯﻭﺝ ﻫﺎﻱ ﺩﺭ ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻩ ﺑﺮﺍﻱ ﺍﺗﺮﻧﺖ ﺩﻩ ﻭ ﻳﮑﺼﺪ ﻣﮕﺎﺑﻴﺖ ﺑﻪ ﺭﻧﮓ ﻧﺎﺭﻧﺠﻲ‬

‫ﻭ ﺳﺒﺰ ﻣﻲ ﺑﺎﺷﻨﺪ‪.‬‬

‫ﺍﺯ ﺩﻭ ﺯﻭﺝ ﺩﻳﮕﺮ )ﺭﻧﮓ ﻗﻬﻮﻩ ﺍﻱ ﻭ ﺁﺑﻲ( ﻣﻲ ﺗﻮﺍﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﻳﮏ ﺧﻂ ﺍﺗﺮﻧﺖ ﺩﻭﻡ ﻭ ﻳﺎ‬ ‫ﺍﺗﺼﺎﻻﺕ ﺗﻠـﻔﻦ ﺍﺳﺘﻔﺎﺩﻩ ﻧﻤﻮﺩ‪.‬‬

‫ﺑﻪ ﻣﻨﻈﻮﺭ ﮐﺎﺑﻞ ﮐﺸﻲ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ UTP‬ﺍﺯ ﺩﻭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ﻣﺘﻔﺎﻭﺕ ﺑﺎ ﻧﺎﻡ ‪) T-568B‬ﻳﺎ‬ ‫‪ ( EIA‬ﻭ ‪) T-568A‬ﻳﺎ ‪ ،( A٢٥٨ ، T&AT‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺗﻨﻬﺎ ﺗﻔﺎﻭﺕ ﻣﻮﺟﻮﺩ ﺑﻴﻦ‬ ‫ﺁﻧﺎﻥ ﺗﺮﺗﻴﺐ ﺍﺗﺼﺎﻻﺕ ﺍﺳﺖ‪.‬‬

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‫ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪T568B‬‬

‫ﻫﻤﺎﻧﮕﻮﻧﻪ ﮐﻪ ﺩﺭ ﺟﺪﻭﻝ ﺯﻳﺮ ﻣﺸﺎﻫﺪﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﻓﺮﺩ ﻫﻤﻮﺍﺭﻩ ﺳﻔﻴﺪ‬

‫ﺑﻮﺩﻩ ﮐﻪ ﺑﺎ ﻳﮏ ﻧﻮﺍﺭ ﺭﻧﮕﻲ ﭘﻮﺷﺶ ﺩﺍﺩﻩ ﻣﻲ ﺷﻮﻧﺪ‪.‬‬ ‫ﮐﺪ ﺭﻧﮓ ﻫﺎ ﺩﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪B٥٦٨T‬‬ ‫ﮐﺎﺭﺑﺮﺩ‬

‫ﺯﻭﺝ‬

‫‪TxData+‬‬

‫ﺩﻭﻡ‬

‫‪TxData-‬‬

‫ﺩﻭﻡ‬

‫ﺭﻧﮓ‬ ‫ﺳﻔﻴﺪ‪/‬‬

‫ﻧﺎﺭﻧﺠﻲ‬ ‫ﻧﺎﺭﻧﺠﻲ‬

‫ﺷﻤﺎﺭﻩ‬ ‫ﭘﻴﻦ‬ ‫ﻳﮏ‬ ‫ﺩﻭ‬

‫‪ RecvData+‬ﺳﻮﻡ ﺳﻔﻴﺪ ‪ /‬ﺳﺒﺰ ﺳﻪ‬ ‫ﭼﻬﺎﺭ‬ ‫ﺁﺑﻲ‬ ‫ﻳﮏ‬ ‫‪RecvData-‬‬

‫ﻳﮏ‬

‫ﺳﻔﻴﺪ ‪/‬ﺁﺑﻲ‬

‫ﭘﻨﺞ‬

‫ﺳﻮﻡ‬

‫ﺳﺒﺰ‬

‫ﺷﺶ‬

‫ﭼﻬﺎﺭﻡ‬ ‫ﭼﻬﺎﺭﻡ‬

‫ﺳﻔﻴﺪ‪/‬ﻗﻬﻮﻩ‬ ‫ﺍﻱ‬

‫ﻗﻬﻮﻩ ﺍﻱ ﻫﺸﺖ‬

‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪B٥٦٨T‬‬

‫‪398‬‬

‫ﻫﻔﺖ‬

‫ﺷﻤﺎﺭﻩ ﭘﻴﻦ ﻫﺎﻱ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪T568A‬‬

‫ﺩﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ ، T568A‬ﺍﺗﺼﺎﻻﺕ ﺳﺒﺰ ﻭ ﻧﺎﺭﻧﺠﻲ ﺑﺮﻋﮑﺲ ﺷﺪﻩ ﺍﺳﺖ ‪ ،‬ﺑﻨﺎﺑﺮﺍﻳﻦ‬

‫ﺯﻭﺝ ﻫﺎﻱ ﻳﮏ ﻭ ﺩﻭ ﺑﺮ ﺭﻭﻱ ﭼﻬﺎﺭ ﭘﻴﻦ ﻭﺳﻂ ﻗﺮﺍﺭ ﻣﻲ ﮔﻴﺮﻧﺪ )ﺳﺎﺯﮔﺎﺭﻱ ﺑﺎ ﺍﺗﺼﺎﻻﺕ‬

‫‪.( telco voice‬‬

‫ﮐﺪ ﺭﻧﮓ ﻫﺎ ﺩﺭ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪A٥٦٨T‬‬ ‫ﺭﻧﮓ‬

‫ﺷﻤﺎﺭﻩ ﭘﻴﻦ‬

‫ﮐﺎﺭﺑﺮﺩ‬

‫‪ RecvData+‬ﺳﻮﻡ‬

‫ﺳﻔﻴﺪ‪ /‬ﺳﺒﺰ‬

‫ﻳﮏ‬

‫‪ RecvData-‬ﺳﻮﻡ‬

‫ﺳﺒﺰ‬

‫ﺩﻭ‬

‫‪TxData+‬‬

‫‪TxData-‬‬

‫ﺯﻭﺝ‬

‫ﺩﻭﻡ ﺳﻔﻴﺪ ‪ /‬ﻧﺎﺭﻧﺠﻲ‬

‫ﺳﻪ‬

‫ﻳﮏ‬

‫ﺁﺑﻲ‬

‫ﭼﻬﺎﺭ‬

‫ﻳﮏ‬

‫ﺳﻔﻴﺪ ‪/‬ﺁﺑﻲ‬

‫ﭘﻨﺞ‬

‫ﺩﻭﻡ‬

‫ﻧﺎﺭﻧﺠﻲ‬

‫ﺷﺶ‬

‫ﭼﻬﺎﺭﻡ ﺳﻔﻴﺪ‪/‬ﻗﻬﻮﻩ ﺍﻱ‬ ‫ﭼﻬﺎﺭﻡ‬

‫ﻗﻬﻮﻩ ﺍﻱ‬

‫ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪A٥٦٨T‬‬

‫‪399‬‬

‫ﻫﻔﺖ‬ ‫ﻫﺸﺖ‬

‫ﻣﻮﺍﺭﺩ ﺍﺳﺘﻔﺎﺩﻩ‬

‫ﻣﺘﺪﺍﻭﻟﺘﺮﻳﻦ ﮐﺎﺭﺑﺮﺩ ﻳﮏ ﮐﺎﺑﻞ ‪ ، straight‬ﺍﺗﺼﺎﻝ ﺑﻴﻦ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ ﻭ ﻫﺎﺏ ‪/‬ﺳﻮﺋﻴﭻ‬

‫ﺍﺳﺖ‪ .‬ﺩﺭ ﭼﻨﻴﻦ ﻣﻮﺍﺭﺩﻱ‪ ،‬ﮐﺎﻣﭙﻴﻮﺗﺮ ﻣﺴﺘﻘﻴﻤﺎ" ﺑﻪ ﻫﺎﺏ ﻭ ﻳﺎ ﺳﻮﺋﻴﭻ ﻣﺘﺼﻞ ﺷﺪﻩ ﮐﻪ ﺑﻪ ﺻﻮﺭﺕ‬ ‫ﺍﺗﻮﻣﺎﺗﻴﮏ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺪﺍﺭﺍﺗﻲ ﺧﺎﺹ‪ ،‬ﮐﺎﺑﻞ ‪ over cross‬ﻣﻲ ﮔﺮﺩﺩ‪.‬‬

‫ﺷﮑﻞ ﻓﻮﻕ ﻳﮏ ﺍﺗﺼﺎﻝ ﺍﺳﺘﺎﻧﺪﺍﺭﺩ ‪ straight‬ﺩﺭ ﮐﺎﺑﻞ ﻫﺎﻱ ‪ CAT5‬ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ ﮐﻪ ﺍﺯ‬ ‫ﺁﻥ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﺗﺼﺎﻝ ﻳﮏ ‪ PC‬ﺑﻪ ﻫﺎﺏ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﺎ ﻣﺸﺎﻫﺪﻩ ﺷﮑﻞ‬ ‫ﻓﻮﻕ ﺍﻧﺘﻈﺎﺭ ﺩﺍﺷﺘﻪ ﺑﺎﺷﻴﺪ ﮐﻪ ‪ TX+‬ﻳﮏ ﻃﺮﻑ ﺑﻪ ‪ TX+‬ﻃﺮﻑ ﺩﻳﮕﺮ ﻣﺘﺼﻞ ﮔﺮﺩﺩ ) ﻋﻤﻼ"‬ ‫ﺍﻳﻦ ﺍﺗﻔﺎﻕ ﻧﻴﺎﻓﺘﺎﺩﻩ ﺍﺳﺖ (‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ ﻳﮏ ‪ PC‬ﺑﻪ ﻫﺎﺏ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﻫﺎﺏ ﺑﻪ ﺻﻮﺭﺕ‬

‫ﺍﺗﻮﻣﺎﺗﻴﮏ ﻭ ﺑﺎ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﻣﺪﺍﺭﺍﺕ ﺩﺍﺧﻠﻲ ﺧﻮﺩ ﮐﺎﺑﻞ ﺭﺍ ‪ X-over‬ﻧﻤﻮﺩﻩ ﻭ ﺑﺪﻳﻦ ﺗﺮﺗﻴﺐ‪،‬‬

‫ﭘﻴﻦ ﺷﻤﺎﺭﻩ ﻳﮏ ﺍﺯ ﮐﺎﻣﭙﻴﻮﺗﺮ ) ‪ ( TX +‬ﺑﻪ ﭘﻴﻦ ﺷﻤﺎﺭ ﻳﮏ ﻫﺎﺏ ) ‪ ( RX +‬ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻫﺎﺏ ﻋﻤﻠﻴﺎﺕ ‪ x-over‬ﺭﺍ ﺍﻧﺠﺎﻡ ﻧﺪﻫﺪ ) ﺩﺭ ﺯﻣﺎﻥ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ‬

‫‪ ، ( Uplink‬ﭘﻴﻦ ﺷﻤﺎﺭﻩ ﻳﮏ ﮐﺎﻣﭙﻴﻮﺗﺮ )‪ (TX +‬ﺑﻪ ﭘﻴﻦ ﺷﻤﺎﺭﻩ ﻳﮏ ﻫﺎﺏ )‪ ( TX +‬ﻣﺘﺼﻞ‬ ‫ﻣﻲ ﮔﺮﺩﺩ ‪ .‬ﺑﻨﺎﺑﺮﺍﻳﻦ ﻣﻬﻢ ﻧﻴﺴﺖ ﮐﻪ ﭼﻪ ﻧﻮﻉ ﻋﻤﻠﻴﺎﺗﻲ ﺭﺍ ﺑﺎ ﭘﻮﺭﺕ ‪ HUB‬ﺍﻧﺠﺎﻡ ﻣﻲ ﺩﻫﻴـــﻢ‬ ‫) ‪ Uplink‬ﻭ ﻳﺎ ﻧﺮﻣﺎﻝ (‪ ،‬ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﻧﺴﺒﺖ ﺩﺍﺩﻩ ﺷﺪﻩ ﺑﻪ ﻫﺸﺖ ﭘﻴﻦ ﺳﻤﺖ ‪،PC‬‬ ‫ﻫﻤﻮﺍﺭﻩ ﻳﮑﺴﺎﻥ ﺑﺎﻗﻲ ﻣﺎﻧﺪﻩ ﻭ ﻫﺎﺏ ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺍﺳﺘﻔﺎﺩﻩ ﺍﺯ ﭘﻮﺭﺕ ) ﻧﺮﻣﺎﻝ ﻭ ﻳﺎ‬

‫‪ (Uplink‬ﻋﻤﻠﻴﺎﺕ ﻻﺯﻡ ﺭﺍ ﺍﻧﺠﺎﻡ ﺧﻮﺍﻫﺪ ﺩﺍﺩ‪.‬‬

‫‪400‬‬

‫ﻧﺤﻮﻩ ﻋﻤﻠﮑﺮﺩ ﺧﻄﻮﻁ ‪T1‬‬

‫ﺍﮐﺜﺮ ﺷﻤﺎ ﺑﺎ ﻳﮏ ﺧﻂ ﻣﺨﺎﺑﺮﺍﺗﻲ ﻣﻌﻤﻮﻟﻲ ﺁﺷﻨﺎ ﻫﺴﺘﻴﺪ‪ .‬ﺩﺭ ﺍﻳﻦ ﻧﻮﻉ ﺧﻄﻮﻁ ﺍﺯ ﻳﮏ ﺯﻭﺝ‬ ‫ﺳﻴﻢ ﻣﺴﻲ ﮐﻪ ﻣﺴﺌﻮﻟﻴﺖ ﺍﻧﺘﻘﺎﻝ ﺻﻮﺕ ﺭﺍ ﺑﻪ ﺻﻮﺭﺕ ﺳﻴﮕﻨﺎﻝ ﻫﺎﻱ ﺁﻧﺎﻟﻮﮒ ﺑﺮﻋﻬﺪﻩ ﺩﺍﺭﺩ‪،‬‬

‫ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺯﻣﺎﻧﻲ ﮐﻪ ﺍﻳﻦ ﻧﻮﻉ ﺧﻄﻮﻁ ﺭﺍ ﺑﻪ ﻳﮏ ﻣﻮﺩﻡ ﻣﻌﻤﻮﻟﻲ ﻣﺘﺼﻞ ﻣﻲ ﻧﻤﺎﺋﻴﻢ‪،‬‬ ‫ﺍﻣﮑﺎﻥ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺗﺎ ‪ ٣٠‬ﮐﻴﻠﻮ ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ ﻓﺮﺍﻫﻢ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺗﺤﻮﻻﺕ ﮔﺴﺘﺮﺩﻩ ﺩﺭ ﻋﺮﺻﻪ ﻣﺨﺎﺑﺮﺍﺗﻲ‪ ،‬ﺍﮐﺜﺮ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺩﺭﺻﺪﺩ‬

‫ﺍﻧﺘﻘﺎﻝ ﺗﻤﺎﻣﻲ ﺗﺮﺍﻓﻴﮏ ﺻﻮﺗﻲ ﺧﻮﺩ ﺑﻪ ﺻﻮﺭﺕ ﺩﻳﺠﻴﺘﺎﻝ ﺩﺭ ﻣﻘﺎﺑﻞ ﺁﻧﺎﻟﻮﮒ ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺍﻳﻦ‬

‫ﺭﺍﺑﻄﻪ ﻣﻲ ﺑﺎﻳﺴﺖ ﺧﻂ ﺁﻧﺎﻟﻮﮒ ﺷﻤﺎ ﺑﻪ ﻳﮏ ﺳﻴﮕﻨﺎﻝ ﺩﻳﺠﻴﺘﺎﻝ ﺗﺒﺪﻳﻞ ﮔﺮﺩﺩ‪ .‬ﺑﺪﻳﻦ ﻣﻨﻈﻮﺭ ﺩﺭ‬ ‫ﻫﺮ ﺛﺎﻧﻴﻪ ‪ ٨٠٠٠‬ﺍﻟﮕﻮ ﻭ ﺑﺎ ﺩﻗﺖ ﻫﺸﺖ ﺑﻴﺖ‪ ،‬ﻧﻤﻮﻧﻪ ﺑﺮﺩﺍﺭﻱ ﻣﻲ ﮔﺮﺩﺩ )‪ ٦٤،٠٠٠‬ﺑﻴﺖ ﺩﺭ‬

‫ﺛﺎﻧﻴﻪ(‪ .‬ﺩﺭ ﺣﺎﻝ ﺣﺎﺿﺮ ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﻫﺎﻱ ﺩﻳﺠﻴﺘﺎﻝ ﻋﻤﻮﻣﺎ" ﺍﺯ ﻓﻴﺒﺮﻧﻮﺭﻱ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺍﻳﻦ ﺭﺍﺑﻄﻪ ﺷﺮﮐﺖ ﻫﺎﻱ ﻣﺨﺎﺑﺮﺍﺗﻲ ﺍﺯ ﮔﺰﻳﻨﻪ ﻫﺎﻱ ﻣﺘﻔﺎﻭﺗﻲ ﺩﺭ ﺧﺼﻮﺹ‬ ‫ﻇﺮﻓﻴﺖ ﻫﺮ ﺧﻂ ﻓﻴﺒﺮ ﻧﻮﺭﻱ‪ ،‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﻣﺤﻞ ﮐﺎﺭ ﺷﻤﺎ ﺍﺯ ﻳﮏ ﺧﻂ‬

‫‪ T1‬ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﻧﻤﺎﻳﺪ‪ ،‬ﻧﺸﺎﻧﺪﻫﻨﺪﻩ ﺍﻳﻦ ﻣﻮﺿﻮﻉ ﺍﺳﺖ ﮐﻪ ﺷﺮﮐﺖ ﻣﺨﺎﺑﺮﺍﺕ ﻭ ﺳﺎﻳﺮ ﺷﺮﮐﺖ‬ ‫ﻫﺎﻱ ﻋﺮﺿﻪ ﮐﻨﻨﺪﻩ ﺳﺮﻭﻳﺲ ﻓﻮﻕ‪ ،‬ﻳﮏ ﺧﻂ ﻓﻴــﺒﺮﻧﻮﺭﻱ ﺭﺍ ﺗﺎ ﻣﺤﻞ ﺍﺩﺍﺭﻩ ﺷﻤﺎ ﺁﻣﺎﺩﻩ ﻧﻤﻮﺩﻩ‬ ‫ﺍﻧﺪ‪ ) .‬ﻳﮏ ﺧﻂ ‪ T1‬ﻣﻤﮑﻦ ﺍﺳﺖ ﺑﻪ ﺻﻮﺭﺕ ﻣﺴﻲ ﻧﻴﺰ ﺍﺭﺍﺋﻪ ﮔﺮﺩﺩ(‪ .‬ﻳﮏ ﺧﻂ ‪ T1‬ﻗﺎﺩﺭ ﺑﻪ‬ ‫ﺣﻤﻞ ‪ ٢٤‬ﮐﺎﻧﺎﻝ ﺻﻮﺗﻲ ﺩﻳﺠﻴﺘﺎﻝ ﻭ ﻳﺎ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺑﺎ ﻣﻴﺰﺍﻥ ‪ ١ / ٥٤٤‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ‬

‫ﺍﺳﺖ‪.‬‬

‫ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺧﻂ ‪ T1‬ﺑﻪ ﻣﻨﻈﻮﺭ ﻣﺒﺎﺩﻻﺕ ﺗﻠﻔﻨﻲ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺧﻂ ﻓﻮﻕ ﺑﻪ ﺳﻴﺴﺘﻢ‬ ‫ﺗﻠﻔﻦ ﺍﺩﺍﺭﻩ ﺷﻤﺎ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ ﺍﺯ ﺧﻂ ‪ T1‬ﺑﻪ ﻣﻨﻈﻮﺭ ﺍﻧﺘﻘﺎﻝ ﺩﺍﺩﻩ ﺍﺳﺘﻔﺎﺩﻩ‬ ‫ﻣﻲ ﮔﺮﺩﺩ‪ ،‬ﺧﻂ ﻓﻮﻕ ﺑﻪ ﺭﻭﺗﺮ ﺷﺒﮑﻪ ﻣﺘﺼﻞ ﻣﻲ ﮔﺮﺩﺩ‪.‬‬ ‫ﻳﮏ ﺧﻂ ‪ T1‬ﻗﺎﺩﺭ ﺑﻪ ﺣﻤﻞ ﺣﺪﻭﺩ ‪ ١٩٢،٠٠٠‬ﺑﺎﻳﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ﺍﺳﺖ )‪ ٦٠‬ﻣﺮﺗﺒﻪ ﺑﻴﺶ ﺍﺯ‬ ‫ﻳﮏ ﻣﻮﺩﻡ ﻣﻌﻤﻮﻟﻲ(‪ .‬ﺿﺮﻳﺐ ﺍﻋﺘﻤﺎﺩ ﺑﻪ ﺍﻳﻨﮕﻮﻧﻪ ﺧﻄﻮﻁ ﺩﺭ ﻣﻘﺎﻳﺴﻪ ﺑﺎ ﻳﮏ ﻣﻮﺩﻡ ﺁﻧﺎﻟﻮﮒ‬

‫‪401‬‬

‫ﺑﻤﺮﺍﺗﺐ ﺑﻴﺸﺘﺮ ﺍﺳﺖ‪ .‬ﻳﮏ ﺧﻂ ‪ T1‬ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﺻﻮﺭﺕ ﻣﺸﺘﺮﮎ ﺗﻮﺳﻂ ﮐﺎﺭﺑﺮﺍﻥ ﻣﺘﻌﺪﺩﻱ‬ ‫ﺍﺳﺘﻔﺎﺩﻩ ﺷﻮﺩ )ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﻮﻉ ﺍﺳﺘﻔﺎﺩﻩ ﮐﺎﺭﺑﺮﺍﻥ(‪ .‬ﻣﺜﻼ" ﺩﺭ ﺻﻮﺭﺕ ﺍﺳﺘﻔﺎﺩﻩ ﻣﻌﻤﻮﻟﻲ ﺍﺯ‬ ‫ﺍﻳﻨﺘﺮﻧﺖ‪ ،‬ﺻﺪﻫﺎ ﮐﺎﺭﺑﺮ ﻗﺎﺩﺭ ﺑﻪ ﺍﺳﺘﻔﺎﺩﻩ ﻣﺸﺘﺮﮎ ﺍﺯ ﻳﮏ ﺧﻂ ‪ T1‬ﻣﻲ ﺑﺎﺷﻨﺪ‪ .‬ﺩﺭ ﺻﻮﺭﺗﻲ ﮐﻪ‬

‫ﺗﻤﺎﻣﻲ ﮐﺎﺭﺑﺮﺍﻥ ﻓﺎﻳﻞ ﻫﺎﻱ ‪ MP3‬ﺭﺍ ‪ Download‬ﻧﻤﻮﺩﻩ ﻭ ﻳﺎ ﻓﺎﻳﻞ ﻫﺎﻱ ﻭﻳﺪﺋﻮﺋﻲ ﺭﺍ ﺑﻄﻮﺭ‬ ‫ﻫﻤﺰﻣﺎﻥ ﻣﺸﺎﻫﺪﻩ ﻧﻤﺎﻳﻨﺪ‪ ،‬ﻇﺮﻓﻴﺖ ﻭ ﭘﻬﻨﺎﻱ ﺑﺎﻧﺪ ﻣﻮﺟﻮﺩ ﺟﻮﺍﺑﮕﻮ ﻧﺨﻮﺍﻫﺪ ﺑﻮﺩ‪ ،‬ﮔﺮﭼﻪ ﺍﺣﺘﻤﺎﻝ‬

‫ﺗﺤﻘﻖ ﭼﻨﻴﻦ ﺷﺮﺍﻳﻄﻲ ﺩﺭ ﻳﮏ ﻣﻘﻄﻊ ﺯﻣﺎﻧﻲ ﺧﺎﺹ ﻭ ﺑﻄﻮﺭ ﻫﻤﺰﻣﺎﻥ‪ ،‬ﮐﻢ ﻣﻲ ﺑﺎﺷﺪ‪.‬‬

‫ﻳﮏ ﺷﺮﮐﺖ ﺑﺰﺭﮒ ﺑﻪ ﭼﻴﺰﻱ ﺑﻴﺶ ﺍﺯ ﻳﮏ ﺧﻂ ‪ T1‬ﻧﻴﺎﺯ ﺧﻮﺍﻫﺪ ﺩﺍﺷﺖ‪ .‬ﺟﺪﻭﻝ ﺯﻳﺮ ﺑﺮﺧﻲ‬ ‫ﺍﺯ ﮔﺰﻳﻨﻪ ﻫﺎﻱ ﻣﺘﺪﺍﻭﻝ ﺭﺍ ﻧﺸﺎﻥ ﻣﻲ ﺩﻫﺪ‪:‬‬ ‫ﻣﻌﺎﺩﻝ‬

‫ﻧﻮﻉ ﺧﻂ‬

‫‪ ٦٤‬ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ‬

‫‪DS0‬‬

‫ﻣﻌﺎﺩﻝ ﺩﻭ ﺧﻂ ‪ DS0‬ﺑﻪ ﺍﺿﺎﻓﻪ ﺳﻴﮕﻨﺎﻟﻴﻨﮓ ) ‪١٦‬‬ ‫ﮐﻴﻠﻮﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ( ﻭ ﻳﺎ ‪ ١٢٨‬ﮐﻴﻠﻮ ﺑﻴﺖ ﺩﺭ ﺛﺎﻧﻴﻪ‬

‫‪ISDN‬‬

‫‪ ١ ٥٤٤‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺪﺍﻝ ‪ ٢٤‬ﺧﻂ ‪( DS0‬‬

‫‪T1‬‬

‫‪ ٤٣ /٢٣٢‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺎﺩﻝ ‪ ٢٨‬ﺧﻂ ‪( T1‬‬

‫‪T3‬‬

‫‪ ١٥٥‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺎﺩﻝ ‪ ٨٤‬ﺧﻂ ‪( T1‬‬

‫‪OC3‬‬

‫‪ ٦٢٢‬ﻣﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺎﺩﻝ ‪ ٤‬ﺧﻂ ‪( OC3‬‬

‫‪OC12‬‬

‫‪ ٢ / ٥‬ﮔﻴﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺎﺩﻝ ‪ ٤‬ﺧﻂ ‪OC48 ( OC12‬‬ ‫‪ ٩ / ٦‬ﮔﻴﮕﺎﺑﻴﺖ ﺩﺭ ﻫﺮ ﺛﺎﻧﻴﻪ ) ﻣﻌﺪﺍﻝ ‪ ٤‬ﺧﻂ ‪OC192 ( OC48‬‬

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