The Research And Implementation Of A P2p Search Technology

Each node of P2P is at an equivalent status, which ask for services from other nodes as a client and also provides services for other nodes as a server. It makes use of the resource and organizes the mass of the shared resource effectively in the Internet and improve the fault tolerance and robustness. The P2P is so important, because it is directly related to the accurate positioning of shared resources index in the Internet.This thesis expounds the brief history and presents situation of P2P networks in and abroad, analyzes the types, characteristics and application of it, discusses the four topology of P2P network:Centralized P2P network technology, Structured P2P network technology, None-structure P2P network technology and Hybrid P2P network technology, and also introduced the small world principle and the power rules.Then the thesis analyses the redundancy in forwarding and the algorithm of P2P tree search, presents the spanning tree.based distributed random local index search algorithm. First, it uses the standards of selective search in high node selection and the "2times hop" role select the distributed indexing nodes, and manage the index of shared resources in all the nodes within the range; then establishes the neighbor node table, node statement table and forward policy; Third, a optimization is made to introduce the search mechanism of random walks and a rule is made that the advance search query should been done before nodes are traverse spanning tree, which not only improves the searching efficiency, hit rate and also saves the cost of time and space for the network and nodes, Forth, it describes and proves the algorithm from the aspects of search space, controllable and the complexity, then compares it with Tree based P2P search algorithm.Finally, it uses the OPNET to achieve simulation and test of the algorithm, collect the simulation experiment data according to the evaluation indicator and then compare the the effect of the algorithm before and after optimized, also with Tree based P2P search algorithm which verify the theoretical research of this thesis and got this research work and the thesis summarized and prospected for future work.