P2I: 一种新的主动队列管理算法

研究了在主动队列管理算法中使用的PI控制器和Proportional控制器之间的优劣．通过引入积分因素，PI控制器可以有效地消除Proportional控制器中存在的“稳态误差”．但是，积分项的引入减慢了系统的反应速度．该文提出一个算法P^2I来解决这个问题．P^2I结合了Proportional控制器和PI控制器的优点．作者使用模拟的方法来验证P^2I的性能．试验结果表明，P^2I在反应速度方面优于PI控制器，同时保持了PI控制器的优点．文中还分析了网络流量特征对主动队列管理算法设计的影响．

P2I: A New Algorithm of Active Queue Management

In this paper we study the tradeoff between proportional controller and PI controller in AQM (Active Queue Management) algorithm design. With the introduction of integral factor, the steady state error in proportional controller is eliminated. However, the integral factor also slows down the response speed. We present a simple algorithm P 2I to solve this problem. P 2I combines the advantage of proportional controller and PI controller. The performance of P 2I is verified and compared with PI controller using ns-2 simulation. P 2I is shown to response much faster than PI controller while keeping the merit of PI controller. We also analyze the big impact of traffic pattern on the design and success of AQM.