Research Of The Peer-to-Peer Based Video-on-Demand System

The internet media streaming services such as Video on Demand (VOD) have grown rapidly in recent years. But the service quality is not good enough, because the Server in Server/Client system model would be limited both on the hard disk I/O speed and internet I/O speed. This kind of model can not support huge capacity to provide media streaming service.In order to raise VOD service quality on the internet, this paper used Peer to Peer technology into VOD service domain, take the advantage of both the P2P model and C/S model. Designed a P2PVOD system, which support a huge capacity, high service quality, real time VCR performance, and is suitable for commercial running.The system allow user to share resources in the system and then make the user share their resources with the system, more users online, more quick the speed of data cache and distribute. Designed sufficient P2P incentive mechanism, by which a service provider can motivate users to contribute resources to system using the design of"Windows streaming"and"fragment streaming"two streaming manners, which could promote the user initiative to share resources with system, make both user and system enjoy the benefits. The system use centralized resource location technology provide the system with a high efficient user and resources information maintain manner, and provide users different service authority and QOS rank, suitable for commercial running. The flexible QOS based local buffer storage and the auto-adapted streaming download strategic solve the problem brought by the un-forecasted feature of the use's behavior, and the difference between user's upload speed and download speed; the"I frame fragment forwarding"mechanism and"I frame index table"can provide user a high QOS real time VCR media service.