Bandwidth Control for Replicated-Stream Multicast Video Distribution

Real time multicast video distribution is an important component of many multimedia applications. Our work addresses the fairness problem in feedback-controlled multicast video distribution systems over best effort networks (such as the Internet). In previous work we proposed, implemented and experimented with a scheme, called destination set grouping (DSG), where a source maintains a small number of video streams (say 3), carrying the same video but each targeted at receivers with different capabilities. Each stream is feedback-controlled within prescribed limits by its group of receivers. Receivers may move among groups as their capabilities or the capabilities of the network paths leading to them change. In this paper we focus on the potential for network overloading caused by the transmission of multiple replicated streams. We propose a number of mechanisms to be implemented at the source and the receivers that can help avert this problem. We also describe an evaluation of these schemes using simulation,and discuss a comparison of replicated stream versus layered encoding approaches.