Towards a distributed TCP improvement through individual contention control in wireless networks

TCP suffers degradation in wireless networks, which is caused by the improper, static definitions on the lower layers. In order to improve the TCP performance in wireless networks, the strategy of the lower layer should be reconsidered. In this paper, the TCP transmission is flattened in order to combine the TCP segment transmission and TCP Acknowledgement (ACK) transmission into one transmission. The performance of TCP is also analyzed, in order to find out the corresponding parameters affecting the TCP throughput. Based on the analysis, contention window size shows as one of the parameters that greatly affects the TCP performance. A discrete-time Markov decision process is adopted in order to solve the TCP throughput maximization. Based on the analysis, a TCP-distributed algorithm is proposed. Several simulations are conducted to verify the improvements of TCP-distributed by comparing both TCP Reno and TCP Vegas. Simulation results show that TCP-distributed can perform better than the two TCP variants, and it also limits the delay in an acceptable range.