Design of a robust observer-based memoryless H _∞ control for internet congestion

Abstract

SUMMARYThis work is concerned with the transmission control protocol(TCP)-based active queue management for alleviating Internet congestion. To achieve the objective, a novel robust observer-based H 1 control scheme is proposed to stabilize the data queue length of the router to a given target. The robust observer is advocated to reconstruct a substitution state of the TCP window size under uncertain Internet environments, wherein the TCP window size is almost impossible to be explicitly measured in practise. Meanwhile, a memoryless H 1 controller is employed to guarantee the system asymptotical stability and further enhance the robustness. With the assistance of a unique nonlinear decoupling method, a feasible controller design method is presented in terms of linear matrix inequality. Compared with the existing literatures, the proposed control principle is more practical, and it can be conveniently implemented into the Internet routers while introduces less computational burden. Finally, the proposed result is embedded into Network Simulator 2 and compared with the other schemes in the literature. Numerical experiments illustrate the effectiveness of the proposed method.

Bounded consensus for multiagent systems by event‐triggered data transmission, time delay, and predictor‐based control

“…However, because the discrete‐time measurements and are out‐of‐date with respect to the current time, the proposed control laws are time‐delayed schemes. It is well known that the time delay usually emerges in communication network and control performance will be easily deteriorated by it . For acquiring a continuous‐time measurement, some predictor‐based consensus laws were proposed recently; however, the communication time delay is completely neglected.…”

“…It is well known that the time delay usually emerges in communication network and control performance will be easily deteriorated by it. 38,39 For acquiring a continuous-time measurement, some predictor-based consensus laws were proposed recently [29][30][31][32] ; however, the communication time delay is completely neglected. Inspired by the literature works, [29][30][31][32] consider the communication time delay; an improved consensus control law is designed as…”

A novel AQM algorithm based on feedforward model predictive control

“…A discrete‐time H∞controller for time‐varying TCP/IP network with uncertainty was presented to handle network congestion . In 2016, Cui et al provided a new H∞ control method, wherein the observer was employed to reconstruct the window size, and a memory less controller was utilized to make the system asymptotically stable …”

“…16 In 2016, Cui et al provided a new H∞ control method, wherein the observer was employed to reconstruct the window size, and a memory less controller was utilized to make the system asymptotically stable. 17 For a given value of the bottleneck queue length, the AQM algorithm is designed to track it as soon as possible. In addition, to prevent the network fluctuations should also be considered.…”

Congestion Control in TCP/IP Routers Based on Sampled-Data Systems Theory

“…Furthermore, external disturbance appears in all practical systems and if they are ignored during the controller design, the stability of the practical closed-loop system cannot be guaranteed. It is known that the H ∞ control has an excellent ability to balance the performance of a system in the presence of external disturbance (Ardestani 2016;Cui et al 2016;El Fezazi et al 2017).…”