1. 1 Chapter 5 The Medium Access Sublayer

2. 2 Chapter 5 The Medium Access Layer 5.1 The Channel Allocation problem - Static and dynamic channel allocation in LANs & MANs 5.2 Multiple Access Protocols - ALOHA, CSMA, CSMA/CD, Collision-free protocols, Limited- contention protocols, Wireless LAN protocols 5.3 Ethernet - Cabling, MAC sublayer protocol, Backoff algorithm, Performance, Gigabit Ethernet, 802.2 Logical Link Control 5.4 Wireless LANs - 802.11 protocol stack, physical layer, MAC sublayer protocol, frame structure

3. 3 5.5 Broadband Wireless - Comparison of 802.11 with 802.16, protocol stack, frame structure 5.6 Bluetooth - Bluetooth architecture, Application, Protocol stack, Frame structure 5.7 Data Link Layer Switching - Bridges from 802.x to 802.y, Local internetworking, Spanning tree bridges, Remote bridges

4. 4 5.1 The Channel Allocation problem 5.1.1 Static channel Allocation in LANs and WANs Frequency Division Multiplexing (FDM)

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7. 7 5.1.2 Dynamic Channel Allocation in LANs and WANs Assumptions 1.Station Model. The model consists of N independent stations, each generates the frame with probability in an interval. Once a frame is generated, the station is blocked. 2.Single Channel Assumption. A single channel is available for all communication. 3.Collision Assumption. If two frames are transmitted simultaneously, they are destroyed and must be retransmitted again later. There are no other errors.

8. 8 4a. Continuous Time. Frame transmission can begin at any instant. 4b. Slotted Time. Time is divided into slots. Frame transmission always begin at the start of a slot. 5a. Carrier Sense. Stations can tell if the channel is in use before trying to use it. 5b. No Carrier Sense. Stations cannot sense the channel before trying to use it.

9. 9 5.2 Multiple Access Protocols 5.2.1 ALOHA 5-1.

10. 10 5-2.

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12. 12 5-3.

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25. 25 5.2.2 Carrier Sense Multiple Access Protocols

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29. 29 5-4.

30. 30 5-5.