The Effect of Reverse Traffic on the Performance of New TCP Congestion Control Algorithms

Several new TCP congestion control algorithms have been proposed to speed up the TCP over very fast networks. All these algorithms propose their own modifications of the increasing/decreasing phases of classic Reno/NewReno TCP. On the other hand, all of them preserve the self-clocking mechanism, which is a fundamental part of the classic Van Jacobson TCP congestion control. An important consequence of the ack-clocking is that a TCP flow can be heavily affected by the presence of reverse traffic provoking congestion along its ack path. This paper uses the ns2 simulator to investigate the effect of reverse traffic on the behavior of the new TCP stacks: BIC TCP, HSTCP, Hamilton TCP (H-TCP), STCP and FAST TCP.