A PI CONTROLLER FOR AQM ROUTERS SUPPORTING TCP FLOWS

摘要

We propose a proportional-integral (PI) controller forrnTCP flows in the Internet. Classical control theory isrnapplied in the design to meet frequency domainrnspecification – phase margin. The PI controller canrnregulate the source window size based on the knowledgernof the queue size to clamp the steady value of queuernlength to the specified reference value. The user canrnspecify proper phase margin to achieve good performancernof AQM. Our PI controller is verified via simulation usingrnOPNET. It is shown to outperform RED significantly.