Congestion control of high speed computer networks: A PID method

Abstract

In this paper, we present a novel method to the design of closed-loop rate-based flow controller for high-speed networks. In this method, a proportional-integral-plus-derivative (PID) controller is adopted, where the control parameters are designed to ensure the stability of the control loop in a control theoretic sense. Based on a general traffic model of computer network and on system stability criterion, it is shown that under PID controller the source rates are regulated, the congestion-controlled network is asymptotically stable in terms of both the buffer occupancy of the destination node and the user transmission rates, and the bandwidth fairness is achieved. The basic control theory approach for the algorithm is firstly presented, and steady state analysis is subsequently given to show how the max/min fairness is achieved in a natural way without additional computation. We then use simulations to show the good dynamic performance of the PID congestion control scheme under a variety of networking configurations and traffics.