Optimal multicast overlay placement for realtime streaming media

Multicast is important for realtime delivery of popular streaming media. Proxy-based multicast is an approach to implementing the multicast function by proxy servers at application levels. Many routing algorithms have been proposed to build an overlay network when proxy locations have been determined. On the other hand, the problem of where to place proxies has not been extensively studied yet. A study on the placement problem for proxy-based multicast is presented in this paper. Performance metrics are studied. A number of algorithms are proposed for multicast proxy placement and their performance is compared.