A Generalized FAST TCP Scheme

Abstract

FAST TCP has been shown to be promising in terms of system stability, throughput and fairness. However, it requires buffering which increases linearly with the number of flows bottlenecked at a link. This paper proposes a new TCP algorithm that extends FAST TCP to achieve (α, n)-proportional fairness in steady state, yielding buffer requirements which grow only as the nth power of the number of flows. We call the new algorithm Generalized FAST TCP. We prove stability for the case of a single bottleneck link with homogeneous sources in the absence of feedback delay. Simulation results verify that the new scheme is stable in the presence of feedback delay, and that its buffering requirements can be made to scale significantly better than standard FAST TCP.