Utility based inter-stream adaptation of layered streams in a multiple-flow IP session

Abstract

Future multimedia applications will evolve to content-rich, interactive presentations consisting of an ensemble of concurrent, related to the presentation scenario, flows. Recent research highlights the importance of co-ordinating adaptation decisions among participating flows in order to share common congestion control state. We exploit models that quantify the effects of the dynamics of hierarchically encoded multimedia content on perceived quality and present a mechanism to apportion the session's aggregate bandwidth among its streams that improves the total session quality. Dynamic bandwidth utility curves are introduced to express the variability of multimedia content and represent the level of quality (or satisfaction) an application/user receives under given bandidth allocations. The relative importance of the participating flows, determined either by the user or the application scenario, is also considered. We discuss our approach and analyse simulation results obtained based on trace-driven simulation.