A rate-based robust queue management system through multi-loop internal model controller with initial value compensation

Abstract

An efficient congestion control approach should gain weighted fairness and also robustness against external disturbances. Moreover, variations in the number of active sources cause a network to operate as a switched system in which the initial values affect the transient response. The main contribution of this article is to design a rate-based adaptive robust queue management contemplating the initial value compensation (IVC). The congestion is avoided via Two-Degree-of-Freedom Internal Model Control protocol as a robust procedure. The utilisation factors are designated according to the delay of each source (weighted fairness) in which the sources will use the maximum value of the bottleneck capacity (maximum utilisation). On the other hand, the number of the users is determined adaptively and effects of non-zero initial values are eliminated through a protocol called IVC. Simulation results through Network Simulator 2 and Simulink software confirm the analytical results and the efficacy of the proposed method.