Benchmarking High Speed TCP Fairness: Why and How Starting Time Matters

Fairness of competing TCP flows is an integral and indispensable part of transport protocol design for next generation high bandwidth-delay-product networks. However, a clear definition and through analysis of fairness is still unavailable. In this paper, we argue why and show how starting time can have a significant impact on the fairness of competing high speed TCP flows. Taking starting time as a metric, promising high speed proposals such as highspeed TCP and scalable TCP are investigated in detail by extensive simulation analysis. It is shown in the paper that, under certain conditions on the starting time, scalable TCP can starve other competing flows, either they are highspeed TCP (inter-protocol) or they are scalable TCP (intra-protocol). By detail analytical and statistical analysis, explanation and computation of characteristic parameters are also provided.