Nonlinear Dynamics in High-speed Wireless Networks Congestion Control Model with TCP LogWestwood+ under RED

Abstract

In this paper, we proposed a first-order discrete time nonlinear dynamic model of congestion control system with TCP LogWestwood+ (TCPLog) connections and random early detection (RED) gateway in high-speed wireless networks. The model is used to analyze nonlinear dynamics of the TCPLog/RED network and its stability with respect to various RED controller and system parameters. Bifurcation and chaos behaviors are shown to occur when parameters varied. By theoretical derivation, the fixed point and the critical value are obtained, and the nature of the bifurcation is determined. Furthermore, bifurcation diagrams and Lyapunov exponent are exploited to verify the theoretical results. Finally, the bifurcation and chaotic phenomena of the congestion control system are numerically studied with TCPLog connections and RED gateway