An efficient cluster-based multi-channel management protocol for wireless Ad Hoc networks

In Ad Hoc networking, cluster-based communication protocol can reduce large amount of flooding packets in route establishment process. However, the 802.11 medium access control (MAC) protocol is not dedicated to cluster-based network architecture. Applying 802.11 MAC protocol to cluster-based network introduces problems of inefficient channel utilization in announcement traffic indication message (ATIM) and data sub-windows for gateway nodes, heavy channel contention in some channels, large power consumption of mobile hosts, and poor utilization of multichannel resources. In this paper, we propose a MAC layer multi-channel management protocol which takes power saving issues into consideration in a cluster-based network topology. The proposed protocol aims at effective utilization of multi-channel bandwidth for data communications among mobile hosts. Features of the proposed protocol includes: (1) preserving the property of fair channel contention in original 802.11 protocol, (2) constructing a proper contention condition for mobile hosts, (3) reducing power consumption for idle mobile hosts, (4) reducing probability of collision and unnecessary power consumption due to heavy contention and (5) decreasing the transmission delay of gateway node through proper management of inter-cluster traffic. Experimental results reveal that the proposed protocol has good performance in network throughputs, average transmission delay time and energy consumption. Keywords802.11, ad hoc network, cluster, MAC protocol, multi-channel, power saving.