A Study And Implementation Of Performance Optimization Strategies In P2P VoD Systems

The Internet is now becoming full of multimedia resources. More and more service providers are joining the industry of streaming media. Among them, some we have already been familiar with. Those service providers of IPTV employed P2P technology to optimize the utilization of the server resources, while the SP like Youtube and Youku are trying to publish client to add P2P technology into their architecture.This paper first looks back into the development history of P2P Streaming from the C/S architecture in the early period to the latest P2P VoD technology. The P2P technology has been changed rapidly till some kind of famous Mesh-based P2P architecture was developed. But recently Network Coding changed the strategy of data disseminating in P2P VoD again.SonicVoD and SandBox are introduced next in this paper. Sonic VoD is a simple system including Network Coding and P2P. And SandBox is developed based on Sonic VoD to fulfill the unimplemented module of Sonic VoD. The experiment of SandBox was running over 200 clients at no more than 50 computers in the lab. There existed one Center Controller to tell the clients to join or leave the system which simulated the normal user behavior. We then analyzed the improvement of the performance by experiments over different aspects in P2P VoD.Finally the paper explorerd one user synchronization model based on subscribing video. The purpose of the model is to make sure there is enough users in one overlay in order to make the best use of users'upload bandwidth which can save the server's bandwidth vise versa. At the same time, making the server to surpport more channels and the channels can be changed according to users'subscribing. In our simulation, we used a greedy algorithm to compute the user synchronization model and found that the server can benefit from the model on the global sight. And referring to our simulation, the saving of the server's bandwidth can be reached 75% at best.