A comprehensive TCP fairness analysis in high speed networks

Abstract

The short-term dynamics of competing high speed TCP flows can have strong impacts on their long-term fairness. This leads to severe problems for both the co-existence and the deployment feasibility of different proposals for the next generation networks. However, to our best knowledge, no root-cause analysis of this observation is available. This is the major motivation of our work. The contribution of the paper is twofold. First, we present our comprehensive performance evaluation results of both inter- and intra-protocol fairness behavior of different TCP versions to get an overall view of these protocols. The analysis has revealed not only the equilibrium behavior but also the transient characteristics besides the dynamic behavior. Second, we show the results of a root-cause analysis to get a deeper understanding in the case of some promising TCP versions. This study does not only fill the “black holes”, i.e. answers the questions which remained unanswered in some cases, but rather goes deeper and investigates questions which have never been asked yet. The work includes flow-level, packet-level, queueing and also spectral analyses. Three loss-based (HighSpeed TCP, Scalable TCP and BIC TCP) proposals and the delay-based FAST TCP are investigated in details with both “dumb-bell” and “parking-lot” topologies.