Business In Networked Environment

Business In Networked Environment

Network Hardware and Software (Protocols) Protocols Agreed-upon formats for transmitting data between connected computers

Open Systems Interconnection (OSI)

Is a protocol that represents a group of tasks (below) as seven successive layers that allow computers to communicate

[edit] OSI Model

Host layers

Media layers

Layer

Function

7. Application

Network process to application

6. Presentation

Data representation and encryption

5. Session

Interhost communication

4. Transport

End-to-end connections and reliability (TCP)

3. Network

Path determination and logical addressing (IP)

2. Data Link

Physical addressing (MAC & LLC)

1. Physical

Media, signal and binary transmission

Network Hardware and Software (Protocols) Ethernet The Ethernet protocol is by far the most widely used. Ethernet uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection). Fast Ethernet Gigabit Ethernet The Transmission Control Protocol (TCP) is one of the core protocols of the Internet Protocol Suite. Whereas IP handles lower-level transmissions from computer to computer as a message makes its way across the Internet, TCP operates at a higher level, concerned only with the two end systems, for example your Web browser and a Web server. I

OSI versus TCP/IP

Network Hardware and Software (Hardware) Connectivity Hardware The hardware that allows computers to be physically connected to different types of networks Common Connectivity Hardware • Connectors • Network Interface Cards (NICs) • Modems • Repeaters • Hubs • Bridges • Multiplexers • Routers • Brouters • Channel Service Units • Gateways

Network Hardware and Software (Hardware) Connectors Used to terminate cables in order to be plugged into a network interface card or another network component Network Interface Card A PC expansion board with its own unique identifier that plugs into a computer allowing it to be connected to a network

Network Hardware and Software (Hardware) Modem (Modulator/Demodulator) Enables computers to connect and transmit data over phone lines by converting the sending computer’s digital signals to analog and back again for the receiving computer

Network Hardware and Software (Hardware) Repeater A network device used to regenerate or replicate a signal as it weakens when traveling across a network Hubs A central point of connection between media segments enabling network extension to accommodate more PCs Bridges Used to connect two different LANs or two segments of the same LAN by forwarding traffic between segments Multiplexer Used to share a communications line among a number of users by converting and combining signals from multiple users for simultaneous transmission over a single line

Network Hardware and Software (Hardware) Router An intelligent device used to connect two or more individual networks. When it receives a signal, it looks up the address and passes it to the appropriate network Brouter Short for bridge router and provides the functions of both Gateways This device performs a protocol conversion so that different networks can communicate even though they speak different languages