Popis: |
A limitation of existing P2P VoD services is their inability to support efficient streamed access to niche content that has relatively small demand. This limitation stems from the poor performance of P2P when the number of peers sharing the content is small. In this paper, we propose a new provider-managed P2P VoD framework for efficient delivery of niche content based on two principles: reserving small portions of peers' storage and upload resources, as well as using novel, weighed caching techniques. We demonstrate through analytical analysis, simulations, and experiments on planetlab that our architecture can provide high streaming quality for niche content. In particular, we show that our architecture increases the catalog size by up to $40\%$ compared to standard P2P VoD systems, and that a weighted cache policy can reduce the startup delay for niche content by a factor of more than three. |