MMAC: An efficient WMATM MAC for multicast communications

Some future broadband multimedia services will require special wireless network features. Especially, higher bandwidth each mobile terminal requires, more important the capability of multicast in radio part comes to be. Legacy wmATM (wireless mobile ATM) MACs have not efficiently supported multicast services. In this paper, we propose an efficient multicast mechanism for the wmATM MAC layer, named MMAC (Multicast MAC). We design the system architecture of MMAC, MAC frame format and slot structure. We adopt GSA (Group Selection Agent) by which BSs can reasonably perform the multicast CAC and Resource Allocation in terms of three factors: Service Classes (e.g., CBR, VBR, ABR/UBR), the number of group members and the requested bandwidth for the multicast channels. Another essential feature of MMAC is to support heterogeneous QoS demand of each MT by filtering cells. This cell filtering is performed by Cell-Filter module. On error recovery, one backup channel is used for all multicast channels. Its size is dynamically allocated according to the condition of MMAC. Finally, we will give the performance evaluation of MMAC by using OPNET network simulator.