Vod Server Based On P2p Network Research And Design

Along with the advancement of network communication and computer technology, the human society is on the way to a broadband network–centered information era. The development of Internet gradually pushed the increment of network customers; bring on a large-scale development of Internet applications. In the meantime, the expanding of network service scale brings a huge challenge to the concurrence of servers. In this thesis we research and discuss the methods with which are used to enhance the performace of network server, and then design and implement a P2P-network-based VOD server.The foundation of VOD service is streaming media service. In a traditional client-server streaming system, the server often becomes the bottleneck due to the high bandwidth and long duration of multimedia streams. In the past few years, how to provide a large scale of streaming media has been the core for the researching. The emergence of P2P network technology brought new way of thinking for the VOD service. The VOD servers on the P2P network make use of resources of common nodes to serve other nodes. It has a good performance without changing the configuration of existing network. It is a good kind of VOD service method that has extensively applied foreground.This thesis studied several server models and network I/O mechanism of the high performance server. Researches the several IO mechanisms when people designs the high performance server, and points out that if applying the traditional network IO model with the high concurrency network connections , the server will crash , but the network bandwidth may not fully be utilized. Through the analysis and comparison of several server models and network I/O mechanism, unifies specific application of VOD server under P2P network, advance a server model of staged-event driven architecture (SEDA) with EPOLL network I/O mechanism.In the server which is based on SEDA, it separates the full networking service to some partitions in pipeline, every thread deals with appointed partition and are self-governed each other. It reduces the parallel granularity, made each partition of the services disposed parallel and every disposing process overlap. It improves the server's performance greatly.The networking I/O employs EPOLL technology, which is imported during Linux kernel 2.6. It adopts single thread to deal with sending to and receiving from internet. It avoids the large system overhead of Thread switching frequency under high concurrency, and improves the server's performance.In the implementation part, this thesis gives out some detailed implementations about several important partitions which relate to the server's performance closely. Finally, through the testing and evaluating with the implemented partitions, it is proved that the server meets our goals that the performance is better than the traditional server.