Direct-DMC for AQM computational complexity reduction in TCP/IP networks

Active queue management (AQM) mechanisms are designed to provide better support for end-to-end congestion control mechanisms of transmission control protocol (TCP) in TCP/IP networks. This paper introduces direct dynamic matrix control (D-DMC) as a new AQM method in dynamic TCP networks. Ability of the controller in handling system delay along with its simplicity and low computational loads makes D-DMC a privileged AQM method in high speed networks. The controller is designed based on a small signal linearized fluid-flow model of TCP/AQM networks. The computational complexity analysis as well as the MATLAB simulation results shows the out-performance of the developed controller for both queue regulation and complexity reduction. Fast response, low queue fluctuations (and consequently low delay jitter), and low packet marking probability are other features of the developed method with respect to other well-known AQM methods such as RED and PI which are also simulated for comparison.