Congestion tracking control for multi-router TCP/AQM network based on integral backstepping

Abstract

With the rapid development of the Internet of things and mobile Internet, more and more data flows into the Internet and will cause congestion of multiple routers in the network. However, most of the current congestion control methods are designed for a single router, which cannot adapt to the situation of multi-router congestion. Therefore, this paper proposes a congestion control algorithm to solve the network congestion problem of multiple routers. The model used in this paper captures the dynamics of Transmission Control Protocol (TCP) and covers the four possible behaviors of the TCP network when congestion occurs. The idea of TCP Active Queue Management (AQM) is to reduce congestion by actively discarding some packets in the queue. Taking the probability of packets marked as dropping as the control input, the congestion problem can be solved by using the backstepping method to make the queue length converge to the desired queue length. In this paper, the classical control strategy, backstepping, is extended to TCP network with multiple bottleneck routers to handle the AQM problem. Inspired by the existing network model with one bottleneck router, a revised model is introduced for TCP/AQM network with multiple bottleneck routers. And then, an AQM method Backstepping Congestion Control for Multi-router (BCCM) is proposed to deal with network congestion based on integral backstepping. Simulation results demonstrate that the convergence time of BCCM is about 10% of that of RED and The packet loss ratio of BCCM is 3 orders of magnitude lower than RED. In addition, BCCM has greater stability when traffic, link capacity, and router locations change.