A novel priority-based probability back-off MAC protocol

The Distributed Coordination Function (DCF) of IEEE 802.11 is one of most commonly used MAC protocol in channel-shared wireless network, but it can't support differentiated services among various applications. In this paper, a novel probability back-off MAC protocol is proposed to provide service differentiation as well as enhance the overall system throughput. We analyze our scheme by using a Markov Chain. The simulation results show that our scheme can properly allocate the channel capacity among stations according to different priorities and obtain a better system throughput than IEEE 802.11 DCF, furthermore, it can be adaptive to the alteration (such as proportion of priority classes, number of stations) of network, While any of the other schemes can not.