Abstract: According to the in-depth research on P2P stream media application, how to improve quality of service is a main aspect in research work.We proposed a CORPC caching management scheme,which defines a best caching capacity of chunk's replicas in a P2P system.Based on media chunk popularity,replica number and peer capacity,CORPC scheme adopts heuristic greedy algorithm to implement cache admission control and replacement policy. This scheme can improve quality-of-service (QoS) of chunks with lower popularity while with little sacrifice of chunks with high popularity.Experiment results show that system QoS is improved obviously with an increase of peers' cache capacity.

Key words: Peer-to-Peer network, Cache, Popularity, Replica, Capacity