Time Based Congestion Control (TBCC) for High Speed High Delay Networks

摘要

High speed networks with high delays present a unique environment where TCP can not efficiently utilize the full bandwidth. In this paper, we present a simple and novel Time Based Congestion Control scheme (TBCC for short) that alleviates RTT unfairness while supporting TCP friendliness and bandwidth scalability. We provide the general framework for TBCC protocol modifications. Then, using a simplified design, we illustrate the scalability of TBCC for improving the efficiency, without sacrificing the fairness of TCP. We assess the RTT unfairness of TBCC and show that the RTT unfairness of TBCC can be firmly guaranteed to be no worse than that of unmodified TCP. Compared with similar protocols such as HSTCP and STCP, TBCC can guarantee the bandwidth scalability and achieve better fairness. The flexible framework of TBCC provides a whole class of design options for improving the performance of TCP in high speed networks.