A MAC layer congestion control mechanism in IEEE 802.11 WLANs

In this paper we propose a novel point-to-point MAC layer congestion control mechanism (MACC) in IEEE 802.11 WLANs. We first analyze the reasons of wired congestion and wireless congestion in TCP and mainly study the latter which TCP could not solve well. Then aiming to alleviate this type of congestion of TCP in WLANs, we bring in the concept of congestion control into MAC layer and propose MACC. The main idea of MACC is using the congestion window to control the sending rate in MAC layer. Being Different from congestion control in TCP which is through reducing the sending rate, MACC controls the congestion through increasing the channel utilization and improving the fairness. Simulation results in various scenarios demonstrate that the performances of network throughput and fairness are improved considerably and also TCP congestion is alleviated much by using MACC.