A variable structure control in active queue management

We use control system techniques to design a variable structure based control scheme in active queue management. By analyzing the robustness and performance of the control scheme for the nonlinear TCP/AQM model, we show that the proposed design has good performance and robustness with respect to the uncertainties of the round-trip time and the number of active TCP sessions, which are central to the notion of AQM. Implementation issues are discussed and ns simulations are provided to validate the design and compare its performance with other peer schemes´ in different scenarios. The results show that the proposed design significantly outperforms the peer AQM schemes in terms of packet throughput, loss ratio and buffer fluctuation.