H∞ controller design for TCP congestion control

This paper addresses a H_∞ TCP controller for end-to-end TCP congestion control. The proposed controller which is based on the algorithm of TCP Vegas is aimed to minimize error term in TCP Vegas and achieve one step optimal solution for TCP congestion control. A series of simulation experiments based on a single bottle-neck FIFO queue model are conducted to compare the new controller with TCP Vegas. The simulation results indicate that H_∞, controller improves TCP congestion performance in terms of higher link utilization, less time delay and better fairness for a heavily congested network. Finally, a dynamic threshold setting schema is developed to improve H_∞ controller for both less congested network and heavily congested network. The significance of the research is that a better TCP congestion controller with higher total throughput, less time delay and more stable congestion window size is achieved.