Optimal proxy cache allocation for efficient streaming media distribution

Abstract — In this paper, we address the problem of efficiently streaming a set of heterogeneous videos from a remote server through a proxy to multiple asynchronous clients so that they can experience playback with low startup delays. We develop a tech-nique to analytically determine the optimal proxy prefix cache al-location to the videos that minimizes the aggregate network band-width cost. We integrate proxy caching with traditional server-based reactive transmission schemes such as batching, patching and stream merging to develop a set of proxy-assisted delivery schemes. We quantitatively explore the impact of the choice of transmission scheme, cache allocation policy, proxy cache size, and availability of unicast versus multicast capability, on the resultant transmission cost. Our evaluations show that even a relatively small prefix cache (10%-20 % of the video repository) is sufficient to re-alize substantial savings in transmission cost. We find that care-fully designed proxy-assisted reactive transmission schemes can produce significant cost savings even in predominantly unicast en-vironments such as the Internet. I