RUN-TIME ADJUSTED CONGESTION CONTROL FOR MULTIMEDIA: EXPERIMENTALS RESULTS
Giuseppe De Marco, M. Longo, F. Postiglione · Journal of Interconnection Networks · 2004
Multimedia communications over Internet should achieve adequate quality of service (QoS) while maintaining 'fairness' in network resources allocation with respect to competing connections. The fairness is usually achieved by means of the congestion control, which could induce high variations on the perceived throughput and then affecting the QoS. On the other hand, the variations of throughput of the multimedia communication can be neglected if a minimum average throughput is guaranteed to the playout buffer used by the application. These considerations can be exploited to solve the conflicting requirements of fairness and QoS. The transport protocol proposed here is a modified version of the window-based datagram congestion control protocol, that implements a TCP-like congestion control mechanism wherein the multiplicative decrease of the congestion window is controlled by a non-linear function. Experimental results show that this modified congestion control algorithm, which in turn is adjusted at run-time based on the estimated mean round-trip time, is capable to provide the average throughput required by the encoding technique adopted for the multimedia data compression, while guaranteeing the required fairness with respect to competing TCP connections.