Research of TCP Vegas Congestion Control Algorithm in Ad Hoc Networks

TCP (Transmission Control Protocol) Vegas congestion control algorithm is studied comprehensively in ad hoc networks. Based on Vegas algorithm, a new improved Vegas3 algorithm is presented. During the congestion avoidance, the improvement measure is to divide communication conditions of networks into more particular states; then to take special countermeasure for special communication condition. This algorithm integrates Vegas and Vegas-A algorithm into one algorithm, and adjusts the parameters alpha and beta of Vegas dynamically for adapting to the change of network conditions. The adjusting of alpha and beta, the dividing of network conditions, and the implementing of different measure, all as far as possible accord with originally Vegas algorithm strategy. The result of our simulation shows that the Vegas3 algorithm is superior to Vegas and Vegas-A algorithm in TCP throughput.