卫星TCP/ATM传输中的明确窗口指示拥塞控制策略研究

摘要

Satellite ATM is a hot topic on satellite communication field in recent years. TCP over satellite ATM is one of the most important research issues because the long propagation delay of satellite channel can reduce the efficiency of TCP congestion control. Since the congestion control of TCP is implemented by using window, we propose an explicit window indication strategy for TCP over UBR. The simulation results show that this method can enhance the link efficiency greatly and keep good fairness; at the same time it works well under VBR background traffic. It is easy to implement; the buffer size requirement of the gateway for zero cell loss is very small and independent of the numbers of TCP sources.%卫星ATM是近年来卫星通信领域的一个研究热点，TCP业务在卫星ATM中的传输是其中一个重要的研究课题。由于在TCP协议中主要是通过对窗口的控制来实现拥塞控制，而卫星信道传输的长延时特性大大降低了TCP层拥塞控制的效率。本文提出一种基于UBR传输的明确窗口指示拥塞控制策略，仿真结果表明在效率、公平性、VBR背景传输下的性能等各方面，取得了比目前广泛使用的Reno TCP更好的结果，并且该算法实现简单，交换机实现零信元丢失的缓冲区很小并且与TCP源连接的数目无关。