Novel MAC layer congestion control algorithm in wireless Ad Hoc networks

In wireless Ad Hoc networks, the congestion was mainly caused by the channel contention in the MAC (media access control) layer. To solve the problem, a new congestion control algorithm, EACC (environment aware congestion control), was presented. Based on watching the wireless environment in EACC, by utilizing the binary exponential backoff, algorithm of IEEE 802.11 node could calculate the MAC layer congestion status. Using this congestion information node can adaptively adjust its packet loss probability and then drop the packet to alleviating the network congestion. In addition, the relationship between throughput and the MAC congestion indication was analyzed according to the IEEE 802.11 DCF medium access mechanism, and which proved the validity of the congestion indication. Simulation results show that the EACC algorithm can accurately judge the network congestion status, significantly increase the network throughput and effectively solve the network congestion problem at the MAC layer.