Active queue management controller design for TCP communication networks: Variable structure control approach

On the basis of variable Structure control (VSC), all active queue management (AQM) controller is presented for I class of TCP communication networks. In the TCP/IP networks, the packet LIMP probability is limited between 0 and 1. Therefore, we modeled TCP/AQM as a rate-based non-linear system with I saturated input. The objective of the VSC-based AQM controller is to achieve the desired queue size and to guarantee the asymptotic stability of the closed-loop TCP non-linear system with saturated input. The performance and effectiveness of the proposed control law are then validated for different network scenarios through numerical simulations in both MATLAB and Network Simulator-2 (NS-2). Both Sets of simulation results have confirmed that the proposed scheme outperforms other AQM schemes. (C) 2007 Elsevier Ltd. All rights reserved.