Research On Resource Search Method Based On P2P Network And Its Application In Distant Education System

P2P network is a dynamic distributed system and each node, existed at random, has the same important role in distribution. Quickly searching the target information in this open and free environment is the focus work of P2P network. The purpose of this thesis aims to improve the search efficiency, helps users to find their wanted materials as soon as possible. The content and innovations of the thesis are mainly discussed as follows:(1) The thesis expounds the technical principles in detail about index search technology, flooding search technology and DHT search technology, analyzes their advantages and disadvantages, especially anatomizes the process of search resources of Chord and CAN algorithms in DHT.(2) To the defects of Chords algorithms, the thesis puts forward P2P network search method based on nodes'physical location and their performance. This newly-designed model fully considers all factors, such as nodes'geographical location, heterogeneity and load balance of network, and implements the code of the node's exiting, adding and searching algorithm. With the simulation software, the model is simulated and the validity is verified.(3) To P2P network route problems, this thesis provides the integrated route method, which tells the information how to go through NAT devices. This enables nodes located behind equipments to communicate freely with other nodes.(4) With the functions of distance education system and the new model of search method, the thesis shows the overall design and workflow of distance education system. It divides the system into several functional modules, and implements some codes of electronic whiteboard module and instant communication module.The thesis focuses on the two points: one is how to consider carefully the factors in the new search method, such as nodes'geographical location, heterogeneity and load balance of network; the other is the information how to go through NAT devices in the communication process of P2P network. The above research results and innovations are helpful to improve search method, and. have raised the efficiency of search resources in P2P network.