Active Queue Management Algorithm Of The Simulation Study

With the rapid development of the Internet, network congestion control, as one of the main means to enhance the performance of the network, becomes one of the hot research areas. The aim of congestion control is to maximize the link utilization, minimize the packets delay, distribute the network resources among users reasonably and drop packets as few as possible. As the supplementary means of the TCP end-to-end congestion control, AQM (Active Queue Management) makes the intermediate node join network congestion control, and becomes a hot research area in congestion control these years.Based on systematical introduction of TCP congestion control and AQM congestion control, some typical AQM algorithms have been summarized, and eight of these algorithms are simulated under many kinds of network environments so as to compare the validity and robustness of each algorithm by ns-2 in this paper.Due to the nonlinearity, changing delay and uncertainty of the network, a fuzzy control AQM algorithm based on input rate and queue variance is proposed in this paper, which can control the plant depending on the expert experience without the exact model of the network. Simulations under many various network environments show that this algorithm can stabilize the queue length to the target value and has good stabilization and robustness.