Fast RTP Retransmission for IPTV - Implementation and Evaluation

With the deployment of IPTV reliability for multicast is becoming an important research topic again. Even though it has been intensively investigated before, there is now an understanding of the deployment scenario and the application requirements that allows solutions to be evaluated in detail. We describe how to design a fast retransmission cache based on recent extensions of RTP. We have implemented a prototype intended for deployment in an access node and explain the necessary trade-offs in the design. The paper also contains a performance evaluation which shows the efficiency of the retransmission functionality to handle losses and its performance in congested networks.