Enhanced congestion control for TCP fairness in ad hoc wireless networks

During the past years, a significant TCP unfairness in ad hoc wireless networks has been reported. This unfairness results from the nature of the shared wireless medium and location dependency. This paper studies TCP performance over multi-hop wireless ad hoc networks. The aim is to improve the TCP fairness while keeping the algorithm as simple as possible, since in previous works the algorithm designs were more complicated. We propose a simple approach to improve fairness based on scheduling (pacing) new packets according to the transmission interval formed from scaled round-trip time (RTT) and congestion window. Our simulation using static and mobile networks shows that, given specific scale parameter x, TCP achieves high fairness and throughput via improved spatial channel reuse, if it operates in certain range of the transmission interval.