Dynamic QoS control of multimedia applications based on RTP

We describe a mechanism for dynamic adjustment of the bandwidth requirements of multimedia applications. The sending application uses RTP receiver reports to compute packet loss. Based on this metric the congestion state seen by the receivers is determined and the bandwidth is adjusted by a linear regulator with deadzone. The suggested mechanism has been implemented and controls the bandwidth of the vic video conferencing system. We ran several experiments on the Internet and on our local ATM network to tune and evaluate the algorithm. The results indicate that the mechanism can be applied to both environments. Since an ATM network has a different loss characteristic than the Internet, different controller parameters must be set.