Congestion Control of TCP-Westwood Using AQM-PI Controller

摘要

This paper concerns TCP Westwood (TCPW), a recently developed modification of TCP, in combination with random early detection (RED), PI and self-tuning PI queue management. Using the fluid-flow model of TCPW and separating the model dynamics through block diagram simplification, it is arrived at an approximate and simplified new model. Based on this approximate model, a PI-AQM (Active Queue Management) controller is designed. The parameters of considered PI controller are tuned through estimating the network parameters. Numerical simulations show that bandwidth utilization and the queue stabilization in the self-tuning PI is improved as compared with the PI and RED algorithms.