Distributed multirate streaming in overlay networks

Many multimedia applications and services based on peer-to-peer paradigms are being envisioned for overlay networks. Multimedia streaming applications typically involve a source that multicasts data to multiple receivers based on unirate multicasting, i.e., the same data rate is delivered to all receivers. However, if the receivers differ significantly in their capabilities, then unirate multicasting either overwhelms slow receivers or starves the fast ones. Some of the challenges involved in supporting streaming in overlay networks include providing multirate multicasting, distributed local processing, and automatic adaptation to network dynamics.;The goal of this dissertation is to develop practical and functionally deployable schemes to simultaneously deliver maximum flow rates to all receivers in media streaming multicast applications over overlay networks. The dissertation achieves this goal by providing a solution that is based on a novel integration of two concepts---layered coding and network coding. First, a centralized multi-rate streaming scheme is presented that integrates layered coding and network coding for multirate multicast to heterogeneous receivers with different rates. Next, a distributed multirate scheme is developed by combining the following three components. First, an available bandwidth estimation tool, M-Perf is proposed for simultaneously estimating the available bandwidth to all receivers in a multicast. Second, a distributed bandwidth partitioning algorithm is presented to decide how the nodes should partition their link bandwidths among concurrent multicast sessions such that all receivers in the multicast get their desired sessions. Third, techniques for data dissemination using network coding are presented to reliably deliver the layers of the stream to all receivers in the multicast so as to satisfy their respective data requirements. Finally, the dissertation proposes a distributed media streaming framework based on the above solutions that solves the multirate multicasting problem for streaming applications in overlay networks.