A Measurement Study of Cache Rejection in P2P Live Streaming System

In P2P system, each peer caches the received data for accessing of other peers. P2P live streaming system audiencepsilas TV-like watching pattern brings unique characteristics for its cache management algorithm. By measuring and studying the cache rejection algorithm used in PPLive with our PPLive crawler, we found a simple but interesting cache rejection algorithm used in PPLive, i.e. the cache rejection of peers is synchronized with the chunk upload of media server on chunk offset. We modeled this algorithm as a fixed-duration virtual buffer which includes the P2P network and peerpsilas local buffer and then verified it in our trace. We finally gave some analysis and explanations for this algorithm. What we found is benefit to the future design and modeling of P2P live streaming system.