1. Telecommunications, P. I AIMS 2710 R. Nakatsu

2. Networks and Telecommunications NETWORK – two or more computers interconnected by a cable (or alternatively, by a wireless connection). TELECOMMUNICATIONS - the electronic movement of information.

3. Telecommunications, P. I: An Overview Networks by degree of centralization: –Peer-to-Peer vs. Client-Server networks Media –Wired –Wireless

4. A Peer-to-Peer Network treats all computers equally and is used primarily in small networks. A Client/Server Network is a network that contains one or more host computers (called “servers”) that provide some type of service to the other computers (called “clients”). Networks By Degree Of Centralization

5. Client/Server Networks Network Server Network Server Shared Database and Software Packages Shared Printer PC Internetwork Processor to Other Networks

6. Client-Server Networks Client/Server networks are the emerging blueprint for all networks today. What are the benefits of client/server computing?

7. Network Media: How is the network connected? WIRED MEDIA transmit information over a closed path (such as a wire). Examples: twisted-pair cable (copper), coaxial cable (copper), and fiber optic cable WIRELESS MEDIA transmit information through the air. Examples: infrared, terrestrial wireless, satellite wireless

8. Wired Media TWISTED-PAIR CABLE - two insulated copper wires twisted in a spiral. Transmissions are sent via electricity. –Coaxial cable has shielding that reduces electrical interference. FIBER OPTIC CABLE - uses a very thin glass or plastic fiber. Transmissions are pulses of light. Question: What are the benefits of fiber optic cable?

9. Wireless Media INFRARED uses a red light (below the visibility of the human eye) to transmit information –Infrared is line of sight. What does this mean? TERRESTRIAL WIRELESS transmit radio signals in a path between land-based devices. Three Examples: 1. Near Field Communication--NFC (short range) 2. Wi-Fi (medium range) 3. Cell Phones (long range) SATELLITE WIRELESS are radio transmission systems in space. Question: What is a limitation of terrestrial wireless?

10. A Comparison Of Media The capacity for information flow is called BANDWIDTH. It is usually measured in bits/second (bps) MediumMax Data RateMax Range Twisted Pair, Cat5e1 Gbps100 meters Twisted Pair, Cat610 Gbps100 meters Terrestrial Wireless100s Mbps20-30 miles Satellite GEO100s Mbps8000 miles (1/3 the earth’s circumference) Fiber Optic Cable100s Gbps2 miles and further

11. Key Considerations for Media Bandwidth (Speed) Reliability Distance Mobility Security