PFED:一种基于预测的公平的主动队列管理算法

PFED:A Prediction-Based Fair Active Queue Management Algorithm

对多个著名的主动队列管理算法进行了深入的理论分析和实验比较,对它们的优点和不足进行了总结,并在此基础上提出了一种新的主动队列管理算法PFED(prediction-based fair early drop)·PFED的主要目标是:①通过对流量较为精确的预测,结合对分组丢弃概率更为合理的计算,将队列长度的变化稳定在一个理想的水平;②对非响应流实施有效的惩罚,提高算法的公平性;③通过合理的分组丢弃将队列(分组)的到达速率控制在链路的服务速率之下·仿真实验表明,PFED很好地实现了上述3个目标·

A novel active queue management algorithm named PFED is proposed, which is based on network traffic prediction. The main properties of PFED are： （1） stabilizing queue length at a desirable level with consideration of future traffic, and an MMSE （minimum mean square error） predictor is used to predict future network traffic; （2） imposing effective punishment upon misbehaving flow with a full stateless method; and （3） maintaining queue arrival rate at or below queue service rate through more reasonable calculation of packet drop probability. To verify the performance of PFED, PFED is implemented in NS2 and is compared with RED and CHOKe with respect to different performance metrics. Simulation results show that PFED outperforms RED and CHOKe in stabilizing instantaneous queue length and in fairness. It is also shown that PFED enables the link capacity to be fully utilized by stabilizing the queue length at a desirable level, while not incurring excessive packet loss ratio.