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Lecture Data communications and networks: Chapter 14 - Forouzan 

This chapter introduces wired local area networks. A wired LAN, viewed as a link, is mostly involved in the physical and data link layers. We have devoted the chapter to the discussion of Ethernet and its evolution, a dominant technology today. | Chapter 14 Wireless LANs Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14. 14-1 IEEE 802.11 IEEE has defined the specifications for a wireless LAN, called IEEE 802.11, which covers the physical and data link layers. Architecture MAC Sublayer Physical Layer Topics discussed in this section: 14. A BSS without an AP is called an ad hoc network; a BSS with an AP is called an infrastructure network. Note 14. Figure 14.1 Basic service sets (BSSs) 14. Figure 14.2 Extended service sets (ESSs) 14. Figure 14.3 MAC layers in IEEE 802.11 standard 14. Figure 14.4 CSMA/CA flowchart 14. Figure 14.5 CSMA/CA and NAV 14. Figure 14.6 Example of repetition interval 14. Figure 14.7 Frame format 14. Table 14.1 Subfields in FC field 14. Figure 14.8 Control frames 14. Table 14.2 Values of subfields in control frames 14. Table 14.3 Addresses 14. Figure 14.9 Addressing mechanisms 14. Figure 14.10 Hidden station problem 14. The CTS frame in CSMA/CA handshake can prevent collision from a hidden station. Note 14. Figure 14.11 Use of handshaking to prevent hidden station problem 14. Figure 14.12 Exposed station problem 14. Figure 14.13 Use of handshaking in exposed station problem 14. Table 14.4 Physical layers 14. Figure 14.14 Industrial, scientific, and medical (ISM) band 14. Figure 14.15 Physical layer of IEEE 802.11 FHSS 14. Figure 14.16 Physical layer of IEEE 802.11 DSSS 14. Figure 14.17 Physical layer of IEEE 802.11 infrared 14. Figure 14.18 Physical layer of IEEE 802.11b 14. 14-2 BLUETOOTH Bluetooth is a wireless LAN technology designed to connect devices of different functions such as telephones, notebooks, computers, cameras, printers, coffee makers, and so on. A Bluetooth LAN is an ad hoc network, which means that the network is formed spontaneously. Architecture Bluetooth Layers Baseband Layer L2CAP Topics discussed in this section: . | Chapter 14 Wireless LANs Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14. 14-1 IEEE 802.11 IEEE has defined the specifications for a wireless LAN, called IEEE 802.11, which covers the physical and data link layers. Architecture MAC Sublayer Physical Layer Topics discussed in this section: 14. A BSS without an AP is called an ad hoc network; a BSS with an AP is called an infrastructure network. Note 14. Figure 14.1 Basic service sets (BSSs) 14. Figure 14.2 Extended service sets (ESSs) 14. Figure 14.3 MAC layers in IEEE 802.11 standard 14. Figure 14.4 CSMA/CA flowchart 14. Figure 14.5 CSMA/CA and NAV 14. Figure 14.6 Example of repetition interval 14. Figure 14.7 Frame format 14. Table 14.1 Subfields in FC field 14. Figure 14.8 Control frames 14. Table 14.2 Values of subfields in control frames 14. Table 14.3 Addresses 14. Figure 14.9 Addressing mechanisms 14. Figure 14.10 Hidden .