Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter Four LAN Access Techniques

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. General concept of a simple queuing model Figure 4.1

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Vulnerable period in the pure ALOHA scheme Figure 4.2

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Throughput versus offered load for pure and slotted ALOHA Figure 4.3

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Transmission attempts and random retransmission delays for colliding packets in slotted ALOHA Figure 4.4

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Successful and unsuccessful transmission attempts for nonpersistent CSMA Figure 4.5

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Throughput S as a function of the offered load G Figure 4.6

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Packet arrivals in slotted nonpersistent CSMA Figure 4.7

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flow diagram for the CSMA/CD protocol Figure 4.8

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Performance comparisons Figure 4.9

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Throughput as a function of G for 1-persistent CSMA/CD Figure 4.10 Reprinted with permission from Takagi and Kleinrock, 17 © 1987, IEEE

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Examples of three types of polling schemes Figure 4.11

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Use of a central LAN switch in a star network architecture Figure 4.12

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. LAN-to-LAN and LAN-to-MAN/WAN switches Figure 4.13

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. The basic concept of a LAN switch Figure 4.14

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Equilibrium throughput curve in slotted ALOHA Figure 4.15

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Equilibrium contours for slotted ALOHA Figure 4.16

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Example of a channel load line Figure 4.17

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Example of a globally stable, lightly loaded system Figure 4.18

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Bistable system: 2 locally stable & 1 unstable equilibrium points Figure 4.19

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Behavior of systems which are (a) stable but overloaded (b) unstable with infinite users Figure 4.20