Comparison of TCP Reno and Vegas in Wireless Mobile Ad Hoc Networks

TCP Reno is the most popular TCP version right now although it was reported as less efficient than the newer Vegas version. In this paper, we investigate and evaluate the performance of these two TCP algorithms in wireless mobile ad hoc networks, which are characterized by multi-hop wireless connectivity and frequently changing network topology. After extensively comparing of them in simulations, we exhibit that Reno may have a serious instability problem which will cause its goodput performance to degrade. Vegas does not suffer from this. We also show how to avoid this problem in Reno by tuning a TCP parameter to a specific value. Another important observation is that TCP Vegas does not outperform Reno when they set this parameter at the same ideal value. There is no major difference between Vegas and Reno, when set at the ideal parameter, even in a mobile environment.