High-performance Streaming Media Server In The P2p Research And Design

The traditional network, namely Internet and Intranet and so on which are current main network forms, has brought a qualitative leap to people's life. Today on the face of the demand for real time and high quality transmission on multimedia video/audio information, the traditional network has encountered great challenge. On the one hand, the traditional network can only provide best -effort service; however it can not guarantee the quality of service for multimedia service especially when network bandwidth, packet loss ratio and the delay are changing frequently and unstable. On the other hand, many media encoders do not take the network own situations into consideration, But real time media such as video/audio is very sensitive on the delay of time. The traditional centralized server takes the whole burden of uploading, so its processing ability and transmission rate is the bottleneck of distribution speed. As the increase of the number of users, the downloading speed of each user will fall down and simultaneously the burden of the server will be very heavy which can even causes the breakdown of the server.On the studying and comparing the exiting content distribution technology and streaming media sever technology and considering capital cost realizing , the high performance streaming media server based on P2P can be designed and realize to overcome the bottleneck. The combination of P2P streaming media technology and content distribution technology and the full use of network idle bandwidth resources and storage resources break through the bandwidth bottle neck of traditional streaming media playing system. It can not only support the high concurrence links of clients but also the clients can have interaction which greatly relieve the pressure of server. This new type distributed file distribution mode overcomes the difficulties of traditional centralized mode pushing the core of network application diffusing from central sever to terminal devices. Meanwhile on this basis we implement further optimization scheme of actively publishing and passively caching and two types of timers to improve the capability of the server and the whole system. The realization of the server is based on the platform of Linux on the spirit of modular design. The modules of the system function on an asynchronous event driven framework based on Epoll. The framework is optimized by the use of the newest feature of Linux 2.6 kernel which provides unified event registration and callback interfaces in that case all operations are through registration events, callback relative processing function when the framework detects asynchronous events. In view of the features of high performance network I/O and high performance disk I/O of streaming media server, and absorb the commonly used experience of network procedure and disk procedure ,we connect network module and disk module by a pipe registered to framework to ensure the independence and high efficiency of network and disk. The documents stored in the disk can be managed in a special way to decrease directory depth and distribute documents well. To accelerate the consulting speed of file index, the system uses secondary index method in memory to realize swift transformation from logical address to physical address to guarantee the high efficiency of disk operation. On the view of actual effects, server can provide continuing and stable high-efficient service to plenty of clients. Thus its design implementation way has some theoretical and practical popularization value.