Robust Rate - Based Flow Controllers for High - speed Networks : The Case ofUncertain Time - varying Multiple Time - delays 1

An H 1 based robust controller is designed for a rate-feedback ow-control problem in single-bottleneck data-communication networks. The controller is robust to uncertain time-varying multiple time-delays in diierent channels. The controller forces the queue length at the bottleneck node to the desired steady-state value aymptotically and also satisses a pricing/fairness condition. Lower bounds for stability margins for uncertainty in the time-delays and for the rate of change of the time-delays are derived. In the nal version of this paper, a number of simulations will be included to demonstrate the time-domain performance of the controller. Trade oos between the uncertainty levels and time-domain performance will also be discussed. time-varying multiple time-delays.