On supporting TCP traffic over ABR connections

In this paper, we study the use of ABR connections for transporting TCP traffic over paths where ATM is only a part of the whole path, the subnet ATM model. We show that when ABR connections are used, both throughput and fairness may be improved by using intelligent gateway congestion control mechanisms. Specifically, we propose the ABR+FB (fair buffering) gateway congestion control scheme based on the observation that the poor performance of TCP over ABR connections is mainly due to the mismatch between the ABR rate control mechanism and the TCP window based congestion control mechanism. We show that the proposed ABR+FB mechanism improves the performance of TCP over ABR connections with respect to both throughput and fairness.