CENG 3331 Introduction to Telecommunications and Networks

Ch. 1.1 Data Communications and Networking for Today’s Enterprise Figure 1.1 Average Downstream Traffic per Internet Subscriber Figure 1.2 Past and Project Growth in Ethernet Data Rate Demand Compare to Existing Ethernet Data Rates Figure 1.3 Simplified Communications Model

1.2 A Communication Model How can a communications system be modeled? –What are the components? –What are the tasks? What is meant by data communications networking? –What are WANS and LANs? –What is circuit switching, packet switching, frame relay, and ATM? What are network protocols and architectures?

1.2 A COMMUNICATIONS MODEL Fig.1-3 A Simplified Communications Model Components –Source –Transmitter –Transmission system –Receiver –Destination

Communication Tasks Transmission System Utilization Interfacing Signal generation Synchronization Exchange management Error Detection and Correction Flow control Addressing Routing Recovery Message formatting Security Network management

1.3 DATA COMMUNICATIONS Fig. 1.4 Simplified Data Communications Model –1. Input information--m. –2. Input data--g(t) –3. Transmitted data--s(t) –4. Received Signal--r(t) –5. Output data--g’(t) –6. Output information--m’ Examples: –Electronic mail--discrete information –Telephone conversation--analog information

1.4 Networks Wide-Area Networks –Circuit Switching –Packet Switching –Frame Relay –ATM Local Area Networks (vs. WANs) –1. Smaller geographical “scope.” –2. Owned by user organization. –3. Higher data rates are used. Wireless Networks

1.5 The Internet Figure 1.5 Key Elements of the Internet Figure 1.6 Simplified View of Portion of Internet Table 1.2 Internet Terminology (page 27)

1.6 An Example Configuration Figure 1.7 A Networking Configuration