1. Computer Networks Set 6: MAC sublayer

2. MAC Sublayer ÑWhen several users contend to use same medium, the DLL is divided into a LLC and a MAC sublayer. ÑLLC handles previously described tasks. ÑMAC handles access to the medium -channel allocation. ÑTwo families of channel allocation stategies: ÑStatic channel allocation: FDM, TDM,... ÑDynamic channel allocation: Allocates channel on a need-to-use basis. Several strategies.

3. MAC sublayer - ALOHA ÑAssumptions: Independent stations, single channel, collision detection, slotted time or random access, carrier sense or not. ÑPure Aloha: Random access, Random wait time

4. MAC Sublayer - ALOHA ÑSlotted Aloha: Slotted time, Synchronization needed.

5. MAC sublayer - CSMA ÑCarrier sense multiple access protocols. ÑPersistent CSMA: Continuous Carrier sense, Random access ÑNonpersistent CSMA: Random Carrier sense, Random access Ñp-persistant CSMA: Random Carrier sense, Slotted access with probability p.

6. MAC Sublayer - CSMA comparison

7. MAC Layer - CSMA/CD ÑCSMA with Collision Detection ÑCSMA/CD can be in one of three states: contention, transmission, or idle.

8. MAC Layer -Collision Free ÑBit map protocol: Ñ Binary countdown protocol:

9. MAC Sublayer - Collision free protocols Ñ

10. Required Reading ÑWeb sites on Aloha, CSMA.