Telecommunications & The Internet Basic Telecom Model

Network Terms

• File server
• Print server
• Gateway - connects dissimilar networks
• Bridge - connects similar networks
• Routers - connects networks & directs traffic
• Similar networks = same network protocols

Transmission on LANs

• 20

• Chapter 8

• Token Ring
• can talk only when you have the token
• cost more than Ethernet
• better for high volume traffic
• Ethernet
• talk whenever you want
• send again if collision
• works best with low volume traffic

Transmission on WANs & VANs

• Packet Switching
• message broken into packets
• packets may take various routes
• message reassembled at destination
• allows load balancing on channels
• Frame Relay
• like packet switching, no error correction

The Internet

• What is the Internet?
• Who owns the Internet?
• Why does the Internet exist?

Evolution of the Internet

• 1970 ARPANET - 15 nodes
• 1972 first email
• 1982 TCP/IP becomes internet standard
• Transmission Control Protocol/Internet Protocol
• 1984 ARPANET - 1,000 nodes
• 1986 NSF-Net backbone on ARPANET
• 1987 ARPANET - 10,000 nodes

Evolution of the Internet

• 1988 - businesses begin to connect to system for research purposes
• 1989 ARPANET - 100,000 nodes
• 1989 link email between CompuServe and ARPANET
• 1990 ARPANET becomes the Internet

Public Networks CompuServe

• 1969 started in Cleveland with single computer
• 1979 provided first email
• 1980 started national service
• Mid-1980s largest online service
• 1995 3 Million users
• 1997 purchased by AOL

Public Networks Prodigy

• 1986 pilot in Atlanta, Hartford, San Francisco
• 1988 national service launched
• 1994 1st to offer WWW access
• 1999 Prodigy Classic discontinued (209,000 members)