A novel admission control algorithm for VOD service in ADSL P2P networks

Network video on demand is one kind of favorite VOD services nowadays. P2P technology is adopted to improve system capacity without increasing infrastructure cost. However the limitation of upstream bandwidth in ADSL networks deteriorates P2P networks' extensible capability. The traditional P2P admission control schemes become inapplicable for network VOD service in ADSL networks. The paper presents a novel admission control scheme for VOD service in ADSL P2P networks. In our scheme, a buffer will be reserved in every client. Our scheme indicates that media server can insure clients playing without interruption in case they are admitted initially. At the same time, the response latency is reduced and the efficiency of utilizing bandwidth is increased. Foremost, the buffer space in client improves P2P extensible capability for ADSL networks. System capacity is increased remarkably than without buffer and it will be infinite in theory if waiting coefficient beta is no less than 1. With waiting coefficient beta increases blocking probability decreases. The new scheme significantly improves the system performance in ADSL P2P networks. The detailed admission control policy is described in the paper.