路由器缓冲区容量的设置问题是近年来路由器研究中的热点课题之一.已有的研究主要集中在流量模型、网络拓扑及设置、路由器体系结构及设置、网络的动态性以及性能评价指标五个维度在研究.本文在现有基于评价指标和流量模型所作研究的基础上,提出了一种新的评价指标——流完成时间比.该评价指标具有不依赖网络属性的优点.本文使用这一评价指标进行了基于自相似流量的仿真实验分析,对SFCTR、AFCTR和FCU这三个流完成时间比的相关性能指标进行了监测,得出过大和过小的缓冲区容量都会造成性能下降的结论,并给出了合理设置路由器缓冲区容量的方法.
The problem of router buffer size is one of the hotspots in recent router research. Existing research focuses on traffic pattern,network topology and configuration, router architecture and configuration, network dynamic and performance evaluation criterion. Based on the existing study on evaluation criterion and traffic pattern, this paper proposes a new evaluation criterion named Flow-Completion Tune Ratio, which does not rely on the network property. Based on this criterion, we perform simulations using self-similar traffic as traffic pattern. Observing SFCTR,AFCTR and FCU,we conclude that too large and too small buffer size will both degrade the network performance. We also provide reasonable method of setting muter buffer size.