1. Wen-Hwa Liao, Wen-Chin Chung Tatung University, Taiwan CMC2009 (International Conference on Communications and Mobile Computing)

2. Outline  Introduction  CD-MAC : Multi channel MAC with channel distribution  Simulation  Conclusion

3. Introduction  MMAC Idle

4. CD-MAC Multi channel MAC with channel distribution  Overview DCW (Decide Channel Windows) EPW (Exchange Packet Windows)

5. CD-MAC Multi channel MAC with channel distribution  Assumptions  Synchronized  Single half-duplex  Decide Channel Window (DCW)  DCW packet : [S_id, D_id, CH_id]  Each node maintains two table  DCW table  Channel list table : [CH_id, Counter] EPW DCW S_idD_idCH_id AC2 BD1 Counter 11 21 30

6.  Broadcasts the DCW packet  The source node F->G CD-MAC Multi channel MAC with channel distribution EPW DCW S_idD_idCH_id AC2 BD1 Counter 11 21 30 FG3 S_idD_idCH_id FG3 (Smallest CL’s counter as its CH_id)

7.  Broadcasts the DCW packet  The source node F->C CD-MAC Multi channel MAC with channel distribution EPW DCW S_idD_idCH_id AC2 BD1 Counter 11 21 30 FC2 S_idD_idCH_id FC2 (Select the CH_id as the destination node)

8.  Broadcasts the DCW packet  Neither the sender nor the other nodes receiver CD-MAC Multi channel MAC with channel distribution EPW DCW S_idD_idCH_id NullE (Itself)3 (Smallest CL’s counter as its CH_id) S_idD_idCH_id AC2 BD1 Counter 11 21 30 NullE3

9.  Each pair nodes transmit control packets on their decided CH_id to compete the access to the data channel. CD-MAC Multi channel MAC with channel distribution

10. Simulation  Half of the nodes are sources  Average of 10 runs ParametersValue Terrain205m*250m Transmission Range250m No. of Nodes40 to 120 No. of Channels1 to 6 Pk. Arrival Rate20 to 40 Size of Pk.512 bytes Size of DCW1 to 9

11. Simulation  Aggregate throughput

12. Simulation  Average delay

13. Conclusion  Proposed a multi-channel MAC protocol that utilizes multiple channels to improve throughput in mobile ad hoc networks.  Improves  network throughput by dividing distributing pair nodes to decrease collisions to compete data channel  the bandwidth utilization