1. Network Communications Chapter 6 Multiplexers and Switching Concepts

2. Mutiplexer Application Figure 6.1

3. 4 to 1 Mux / DeMux Figure 6.2 Multiplexer Figure 6.3 Demultiplexer

4. TDM Multiplexer MUX 4*1 AAA B-B CCC -DD Inputs Output -CBA DC-A DCBA t0t1t2t0t1t2 Frame #3 #2 #1 Figure 6.4

5. FDM (Broadcast Analog TV) Figure 6.5

6. Statistical Multiplexer (Packets) SPM AAA -BB CC- DDD Output DCA DCBA DBA Figure 6.6

7. Digital Telephone System Central Office Central Office Digital Signal Analog Signal Figure 6.7

8. Sampling - PAM Pulse Amplitude Modulation Figure 6.8 Analog Signal Pulse Amplitude Modulation (PAM)

9. Analog / Digital Conversion Figure 6.9

10. T1 (DS1) Figure 6.10 TDM PCM Analog 1 Analog 2 PCM Analog 24 1.544 Mbps Digital signal Voice Inputs Digital DS-0 DS-1 (8 bit/sample)*(24 ch/frame) = 192 bit/frame add 1 synchronization bit/frame for 193 b/frame Multiply by the sampling rate of 8 kHz = 1.544 Mbits/sec (64 kbit/sec each channel)

11. Digital Telephone Transmission Figure 6.11: DS-1 Frame Format Table 6.1: US TDM Standards

12. A Fully Connected Network Computer AComputer B Computer CComputer D Figure 6.12

13. Connecting Stations Through Switches Figure 6.13

14. Circuit Switching Figure 6.14 C D E Switch 1Switch 2 A B 1 2

15. Packet Switching (A Virtual Circuit) Switch #1 Switch #3 Switch #2 Switch #4 Switch #5 Destination Virtual Connection CBA Source C A B Figure 6.15