Kalman filter-Based Approximation of a Network Calculus TCP Controller

Delay-based TCP congestion avoidance methods such TCP Vegas, enhanced Vegas, and fast TCP all suffer from throughput degradation as illustrated by their inability to fully utilize the link bandwidth in a bidirectional bottleneck link topology. In this paper, we propose a Kalman filter implementation of a TCP congestion avoidance scheme that is derived by approximating the ideal window controller generated from an approach based upon network calculus (NC) notions. With an improved bandwidth estimation method, this Kalman filter-based NC controller presents a marked improvement over all other delay-based TCP congestion avoidance schemes. In ns-2 simulations, it is able to fully utilize the link bandwidth in both directions with the router queue levels achieving stable set points with reduced queueing delay variation under highly dynamic conditions.