Active queue management with discrete sliding modes in TCP networks

In this paper, a new active queue management (AQM) algorithm for data traffic control in TCP/IP networks is developed. The algorithm design is based on the principles of discrete sliding-mode control. Unlike majority of earlier studies, the design procedure considers the effects of both non-negligible delay in transferring data and feedback information and unpredictable capacity variations. The switching function is selected to incorporate a delay compensation mechanism, which ensures efficient network operation even for large bandwidthdelay product connections. The proposed algorithm, implemented as a packet marking scheme, is tested in discrete event ns-2 simulator. The results show that the algorithm provides fast convergence to steady state after sudden, unanticipated capacity changes. By generating smaller overshoots, the proposed algorithm also allows for reducing buffer space requirements to avoid packet loss as compared to the benchmark AQM solutions

A simple, rate-based traffic control solution for IPV4 networks using Linux-based hop-by-hop closed loop and queuing discipline implementation

In this chapter an implementation of hop-by-hop closed loop mechanism for IPv4 networks has been proposed. The choice· of IPv4 network as the place where traffic control utilizing such a mechanism should be performed, as well as the choice of hopby- hop strategy for closed loop design has been motivated based on the comparison with possible alternative choices. Next, the design of a hop-by-hop closed loop algorithm for specific IPv4 network node (router) has been presented. The limitations of IPv4 protocol design taken from the perspective of the proposed closed loop design have been reviewed, and the solution, which is to use and extend features that are available in the current Linux kernel, has been shown. Finally, a simple, rate-based traffic control algorithm that utilizes the hop-by-hop implementation to limit the sending rate of the neighbour nodes according to the available bandwidth measured by the node that acts as the controller, has been proposed. Two practical experiments with the results showing the benefits of performing traffic control the proposed way have been also presented