Mis Lecture 4
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View Mis Lecture 4 as PDF for free.
More details
- Words: 1,210
- Pages: 29
Chapter 3
Networks and Telecommunications
Outline ¾ ¾ ¾ ¾ ¾
¾ ¾
What is the value of a single computer? Why are computer networks so important in today’s businesses? What components do you need to install to create a network? Why does it matter how your computer is connected to the network? How is it possible that you can connect your computer to a network at the office, at home, or while on the road, even overseas? What is the Internet, how is it controlled, and how does it work? What problems are you likely to encounter if you need to connect to a supplier in a different country?
Internal Teamwork Communication Scheduling Sharing
Networks Internet
External Suppliers Customers Banks
Sharing Data: Transactions
Internet
Database Management System and Web Server
Sharing Data: Decisions & Searches ¾ ¾
Decisions & searches Teamwork & joint authorship
Team Document
Report and Comments
File Server and Database
Data and Tools
Sharing Data: E-mail
Internet 2. Message transferred to account on server.
3. Transferred via the Internet to the destination account.
1. User creates e-mail message.
4. Message received when user checks email.
Sharing Data: Calendars
8:00
Mgt meeting
8:30
(open)
9:00
Staff meeting
9:30
Staff meeting
10:00
New meeting
Hardware Sharing Printers Storage Processors
¾ ¾ ¾
Tape Drive (backup)
Corporate or external computer access
Workstations
Shared Printer ¾ ¾ ¾
Server
Files are transferred from workstations to the server. Software automatically copies files to tapes. LAN administrator can restore files if needed.
Packet-Switched Networks ¾
Data, Voice, Video
All converted to packets Packet has data, destination, and Voice source address Switched services Chicago Packets routed C as needed Reassembled 4 at destination
Sent as packets: 1 2 3 4 5 B
2 New York
A 1
E
Atlanta Dallas
5
Computer
D
3 Sent as packets: A B C D E
¾
¾
Servers Work stations
Media
¾
Network Components
Computers
Personal Computer
Cables Fiber optic Radio Infrared
Personal Computer
LAN card
LAN card
Connection devices
Internet LAN card
Router or Switch
LAN card
Firewall Server
Shared Printer
Server Scalability Server farms distribute the workload. Add more computers for more power.
Sun 10000
Sun 3800
Increasing performance within a product family. Rack mount server farm. Compaq
Sun Ultra 5
Network Transmission Media ¾ ¾ ¾
Electricity Fiber optics Radio waves
Fiber Optic Cable Example: Long distance phone lines reflective cladding
Twisted Pair Example: Local phone lines
glass or
plastic
Radio or Micro Waves Example: Cellular phones
Coaxial Example: Cable TV
antenna Shield
Fiber Optics ¾ ¾ ¾ ¾
Faster More data Less magnetic interference Long stretches without repeaters
900 copper wires can be replaced by one fiber optic line (for telephone connections).
KH z -1 65 0
LF
MF
HF
Sound Radio Micro Light
Frequency differences
Amount of data Distance Interference / Noise
10M
88 M
:
FM
VHF
UHF 100M
Microwave Optical 1G
10G
Pu b Pu l i c bl Sa i f C c S ety: el a lu fet 15 la y: 0 Pe C o r r ph 46 M rs dl . C es on 0M 16 om s p es -5 0M : . S ho 80 00 Hz y s ne 0 M MH (P s (s H C z z S) om PC : 1 e ) : .8 9 S ET 5 G 0 0 : - 2 MH 2 z . G H 2G z H z
1K 100K similarly 1M All waves behave
¾
TV :
AM :
VLF 100 ¾
54 M
55 0K
su bm ar in es N av y/
ELF
-2 16 M H -1 z 0 TV 8 : M 22 H z 0M -5 00 M H z
Frequency Spectrum
http://www.jsc.mil/images/speccht.jpg
http://www.ntia.doc.gov/osmhome/allochrt.pdf
Hertz
Shared Connections
With shared connections, machines have to take turns, and congestion can slow down all connections.
With switched connections, each computer has the full bandwidth of the connection at all times. Performance depends on how fast the switch can handle connections.
¾ ¾
Connecting Networks
The need for standards A changing environment
Internet Backbone fiber optic Routers or Switches Switch
Hub Hub Radio-based network
Shared-Media Network
Tap
Shared Media
Switched Network Switch
Servers
Workstations/PCs
Enterprise Network Building 1
Building 2 Fiber optic Switch
Servers Firewall
Workstations/PCs
Internet – ISP Subsidiary
¾ ¾
Client/Server Network
Client server Peer-to-peer
Operating system Multitasking Server
Server
Workgroup Printer Workgroup Printer Clients Clients
ISO-OSI Reference Model
Layer 7
Application
Layer 6
Presentation
Layer 5
Session
Layer 4
Transport
Layer 3
Network
Layer 2
Data Link
A
R C
Layer 1
Physical
A
R C
Application
Original Data
Presentation
Translate Sign on and resources
Session Transport
Data Packet
R
Add routing data
Network
Addresses & Error Check
A
Physical Media
Data Link R C
Physical
Introduction to the Internet ¾ ¾
No control Services
¾
Mail Telnet FTP WWW
WEB searching
AltaVista HotBot Lycos WebCrawler Yahoo
The Internet
How the Internet Works Network service provider (NSP) T1: 1.544 Mbps T3: 44.736 Mbps
OC3: 155.52 Mbps OC12: 622 Mbps
Backbone network
Internet service provider (ISP) Phone company
Individual
Cable company
Phone company
Dial-up: 33.3 - 56 Kbps ISDN: 128 Kbps DSL: 256 Kbps - 6 Mbps Cable: 1.5 Mbps
Company Web site
¾
Backbone providers
¾
AT&T SBC MCI Sprint Qwest
Internet Connections ¾
¾
Network service providers
1998: 39 AGIS AT&T Cable & Wireless IBM MCI/Worldcom Qwest Sprint UUNet
Phone companies
Cable companies
¾
AT&T Cablevision Regional.
Satellite
¾
Regional Bell operating companies (RBOCs) (6) Competitive local exchange carriers (CLECs) (new)
Direct Satellite Starband
Internet service providers
America Online Microsoft Network Earthlink
Domain Name System Registration Internic.org
Internet World
DNS Registration
ISP
207.46.250.222 www.microsoft.com Microsoft Corporation One Microsoft Way Redmond, WA 98052 US
Arin.net Net Range 207.46.0.0 – 207.46.255.255 MicrosoftGlobal-Net
Real World Internet entities are anchored to the real world through the DNS registration and through their ISP. If they tell the truth!
M-Commerce Internet access everywhere Cell phones PDAs Laptops
Great potential Limited usability Better than voice?
Cell Phones and Wireless Communication Wireless cells work by handing off the wireless connection to the next tower as the caller moves. Connections to multiple towers at one time enables the system to triangulate to get a fairly precise location of the cellular device--even when it is not in a call. Location knowledge will make it possible (although perhaps not desirable) to offer new business opportunities as people move into range.
Global Telecommunications ¾
Technical problems
¾
Political complications
¾
Multiple standards Language Developing nations Time zones Limits to space & waves Transborder data flows Taxes Privacy Accessibility
Cultural issues
What is an object? Management & control
Cases: Wholesale Suppliers Annual Revenue 6 5
Billion $
4 W.W. Grainger Univar
3
Ow ens & Minor 2 1 0 1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
How do suppliers connect to customers?
Networks and Telecommunications
Outline ¾ ¾ ¾ ¾ ¾
¾ ¾
What is the value of a single computer? Why are computer networks so important in today’s businesses? What components do you need to install to create a network? Why does it matter how your computer is connected to the network? How is it possible that you can connect your computer to a network at the office, at home, or while on the road, even overseas? What is the Internet, how is it controlled, and how does it work? What problems are you likely to encounter if you need to connect to a supplier in a different country?
Internal Teamwork Communication Scheduling Sharing
Networks Internet
External Suppliers Customers Banks
Sharing Data: Transactions
Internet
Database Management System and Web Server
Sharing Data: Decisions & Searches ¾ ¾
Decisions & searches Teamwork & joint authorship
Team Document
Report and Comments
File Server and Database
Data and Tools
Sharing Data: E-mail
Internet 2. Message transferred to account on server.
3. Transferred via the Internet to the destination account.
1. User creates e-mail message.
4. Message received when user checks email.
Sharing Data: Calendars
8:00
Mgt meeting
8:30
(open)
9:00
Staff meeting
9:30
Staff meeting
10:00
New meeting
Hardware Sharing Printers Storage Processors
¾ ¾ ¾
Tape Drive (backup)
Corporate or external computer access
Workstations
Shared Printer ¾ ¾ ¾
Server
Files are transferred from workstations to the server. Software automatically copies files to tapes. LAN administrator can restore files if needed.
Packet-Switched Networks ¾
Data, Voice, Video
All converted to packets Packet has data, destination, and Voice source address Switched services Chicago Packets routed C as needed Reassembled 4 at destination
Sent as packets: 1 2 3 4 5 B
2 New York
A 1
E
Atlanta Dallas
5
Computer
D
3 Sent as packets: A B C D E
¾
¾
Servers Work stations
Media
¾
Network Components
Computers
Personal Computer
Cables Fiber optic Radio Infrared
Personal Computer
LAN card
LAN card
Connection devices
Internet LAN card
Router or Switch
LAN card
Firewall Server
Shared Printer
Server Scalability Server farms distribute the workload. Add more computers for more power.
Sun 10000
Sun 3800
Increasing performance within a product family. Rack mount server farm. Compaq
Sun Ultra 5
Network Transmission Media ¾ ¾ ¾
Electricity Fiber optics Radio waves
Fiber Optic Cable Example: Long distance phone lines reflective cladding
Twisted Pair Example: Local phone lines
glass or
plastic
Radio or Micro Waves Example: Cellular phones
Coaxial Example: Cable TV
antenna Shield
Fiber Optics ¾ ¾ ¾ ¾
Faster More data Less magnetic interference Long stretches without repeaters
900 copper wires can be replaced by one fiber optic line (for telephone connections).
KH z -1 65 0
LF
MF
HF
Sound Radio Micro Light
Frequency differences
Amount of data Distance Interference / Noise
10M
88 M
:
FM
VHF
UHF 100M
Microwave Optical 1G
10G
Pu b Pu l i c bl Sa i f C c S ety: el a lu fet 15 la y: 0 Pe C o r r ph 46 M rs dl . C es on 0M 16 om s p es -5 0M : . S ho 80 00 Hz y s ne 0 M MH (P s (s H C z z S) om PC : 1 e ) : .8 9 S ET 5 G 0 0 : - 2 MH 2 z . G H 2G z H z
1K 100K similarly 1M All waves behave
¾
TV :
AM :
VLF 100 ¾
54 M
55 0K
su bm ar in es N av y/
ELF
-2 16 M H -1 z 0 TV 8 : M 22 H z 0M -5 00 M H z
Frequency Spectrum
http://www.jsc.mil/images/speccht.jpg
http://www.ntia.doc.gov/osmhome/allochrt.pdf
Hertz
Shared Connections
With shared connections, machines have to take turns, and congestion can slow down all connections.
With switched connections, each computer has the full bandwidth of the connection at all times. Performance depends on how fast the switch can handle connections.
¾ ¾
Connecting Networks
The need for standards A changing environment
Internet Backbone fiber optic Routers or Switches Switch
Hub Hub Radio-based network
Shared-Media Network
Tap
Shared Media
Switched Network Switch
Servers
Workstations/PCs
Enterprise Network Building 1
Building 2 Fiber optic Switch
Servers Firewall
Workstations/PCs
Internet – ISP Subsidiary
¾ ¾
Client/Server Network
Client server Peer-to-peer
Operating system Multitasking Server
Server
Workgroup Printer Workgroup Printer Clients Clients
ISO-OSI Reference Model
Layer 7
Application
Layer 6
Presentation
Layer 5
Session
Layer 4
Transport
Layer 3
Network
Layer 2
Data Link
A
R C
Layer 1
Physical
A
R C
Application
Original Data
Presentation
Translate Sign on and resources
Session Transport
Data Packet
R
Add routing data
Network
Addresses & Error Check
A
Physical Media
Data Link R C
Physical
Introduction to the Internet ¾ ¾
No control Services
¾
Mail Telnet FTP WWW
WEB searching
AltaVista HotBot Lycos WebCrawler Yahoo
The Internet
How the Internet Works Network service provider (NSP) T1: 1.544 Mbps T3: 44.736 Mbps
OC3: 155.52 Mbps OC12: 622 Mbps
Backbone network
Internet service provider (ISP) Phone company
Individual
Cable company
Phone company
Dial-up: 33.3 - 56 Kbps ISDN: 128 Kbps DSL: 256 Kbps - 6 Mbps Cable: 1.5 Mbps
Company Web site
¾
Backbone providers
¾
AT&T SBC MCI Sprint Qwest
Internet Connections ¾
¾
Network service providers
1998: 39 AGIS AT&T Cable & Wireless IBM MCI/Worldcom Qwest Sprint UUNet
Phone companies
Cable companies
¾
AT&T Cablevision Regional.
Satellite
¾
Regional Bell operating companies (RBOCs) (6) Competitive local exchange carriers (CLECs) (new)
Direct Satellite Starband
Internet service providers
America Online Microsoft Network Earthlink
Domain Name System Registration Internic.org
Internet World
DNS Registration
ISP
207.46.250.222 www.microsoft.com Microsoft Corporation One Microsoft Way Redmond, WA 98052 US
Arin.net Net Range 207.46.0.0 – 207.46.255.255 MicrosoftGlobal-Net
Real World Internet entities are anchored to the real world through the DNS registration and through their ISP. If they tell the truth!
M-Commerce Internet access everywhere Cell phones PDAs Laptops
Great potential Limited usability Better than voice?
Cell Phones and Wireless Communication Wireless cells work by handing off the wireless connection to the next tower as the caller moves. Connections to multiple towers at one time enables the system to triangulate to get a fairly precise location of the cellular device--even when it is not in a call. Location knowledge will make it possible (although perhaps not desirable) to offer new business opportunities as people move into range.
Global Telecommunications ¾
Technical problems
¾
Political complications
¾
Multiple standards Language Developing nations Time zones Limits to space & waves Transborder data flows Taxes Privacy Accessibility
Cultural issues
What is an object? Management & control
Cases: Wholesale Suppliers Annual Revenue 6 5
Billion $
4 W.W. Grainger Univar
3
Ow ens & Minor 2 1 0 1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
How do suppliers connect to customers?
Related Documents
Mis Lecture 4
May 2020 3
Mis Lecture 3
May 2020 4
Lecture 2 Mis
May 2020 6
Lecture 4
June 2020 7
Lecture 4
August 2019 24
Lecture 4
May 2020 14More Documents from "Ashok K"
Chap 006
May 2020 11
Chap 012
May 2020 11
Chap 011
May 2020 8
Networking Essentials Notes
May 2020 10
Chap 003
May 2020 4