Transmission of Layered Video Streams in a Differentiated Services Network

Multimedia applications are becoming increasingly popular on the Internet. These include semi real-time applications like video playback, but also interactive applications with hard real-time requirements like Internet telephony or videoconferencing. If current hierarchical video encoding techniques are used, great benefits can be gained by applying the different levels of forwarding guarantees of the Differentiated Services Assured Forwarding. Doing so allows finely tuned reactions to congestion in the network, based on the importance of the individual data packets, which is given by the hierarchy of the video encoding layers. In this paper we compare different queue management and scheduling models, which can form the basis of an Assured Forwarding, for the transmission of hierarchical encoded video streams. We show simulation results, which prove the usefulness of this approach and, which allow for a comparison of the different models that are investigated.