Parameter tuning of rate-based congestion control algorithms and its application to TCP over ABR

Abstract – In this paper, the rate-based congestion control algorithm that has been standardized in the ATM Forum is evaluated. Its behavior is analyzed by utilizing a firstorder fluid approximation to provide control parameter tuning. We obtain the maximum queue length at the switch and conditions for avoiding under-utilization. The results are then applied to TCP over ABR service class. More specifically, we evaluate the TCP-level performance through a simulation technique when TCP is applied to ABR service class with the rate-based congestion control. We first compare rate-based control of ABR service and EPD applied to UBR service, and show that rate based congestion control achieves better fairness and higher throughput in most circumstances. However, we demonstrate that rate-based control requires careful tuning of control parameters to obtain its effectiveness. I