P2p-the Vod Caching Strategy And Simulation

Data cache strategy is one of the key technologies of the streaming media software play quality, the usual cache strategy of the current streaming media player software is SVC (Single video cache), the strategy cache the data which peers are watching, However, in the current video-on-demand system, the user viewing behavior like Zipf, most users in the system demand the most popular video, but there are also exist a large number of cold video, because SVC stragety cache the current video user're watching, then in the network it caches more popular video data copy but less cold video video data, when peers watching the cold video, because there are less data in the network, it will exists the video on the peer will play unsmoothly and frequently requests the server to get the data segment they need, it is because exists such problem, so this paper, presents a P2P-VOD system cache strategy: Multi Video Cache(MVC), the strategy prompt out based on analysis the SVC cache strategy,according to the characteristics of the p2p-vod on demand system, in order to improve the fluency of the video playback and the server load. In P2P-VOD system the continuous of video playback, the requested of server and the degree of customer satisfaction are important factors in the system, but the SVC cache strategy in current system did not fully take into account of peers help each other cache the cold-hot video data. so the paper prompt the MVC cache strategy, the strategy take fully account of the hot-cold and the popular value which cause the the whole unequilibria in on-demand video system, improve the data quantity of cold video, in the case of peers are growing more, peers watching hot video help peers wathing cold video cache data segment, when the server traffic inadequate, improve the fluecy of the video and raise the server's node.In order to analyze the performance of MVC strategy, the thesis utilizes Oversim + INET + OMNeTpp to simulate this strategy in P2P network. The simulation results are analyzed to verify the performance of MVC according these bases: user's play fluency, the server's load. After that, a conclusion can be drawn that the MVC cache stragety works relatively better than SVC at the paly fluency and peers frequency request the server. it has strong self-adaptability and practicality.