A Fuzzy Logic Based Congestion Control Algorithm Suitable for IP-Based Broadband Satellite Networks

A novel RED algorithm named as SFPID-RED is proposed in this paper, which uses self-tuning fuzzy proportional integral derivative/differential (PID) controller to adjust the maximum drop probability of RED based on TCP fluid model. Thus, stable router buffer queue size is obtained, the dynamic self-adaptability of the networks is accomplished, and meanwhile the drawbacks of static RED parameters setting are overcome. In terms of the characteristics that satellite links are vulnerable to weather and microwave, a fuzzy control system is built. Several sets of experiments are carried out in MATLAB to valuate the step response of queue length. It is verified that SFPID-RED has the shortest response time, the highest robustness and utilization compared with the PI, PID and RED. SFPID-RED is also testified suitable to IP-based broadband satellite networks which have dynamic large bandwidth and delay.