Research On The P2P Technology And Application In File Sharing System

Client/Server architecture is one of the most popular distributed computing schemes in recent years. It divides tasks between computers with different roles, but its centralized infrastructure becomes an obvious limitation in decentralized environments. The resources are stored at a few servers whose amount is very small compared with the total number of computers in the systems. When the systems grow larger, it will definitely become the bottleneck of network bandwidth and system performance. In order to provide continued and reliable access to resources, the servers have to run complicated load-balance and fault-tolerance algorithms locally. Meanwhile, the limited capacity of servers also bounds the amount of sharing information. With the fast development of broadband network in China, users who have great amount of resources will still be kept at the edge of the Internet. At the same time, some P2P information sharing applications like Napster and Gnutella are getting popular throughout the Internet, which made people pay more attention to the P2P technology.In recent years, P2P technology is widely used in file-sharing applications. P2P offers a peer to peer method for information sharing, which has become popular among Internet users. The potential of P2P technology is well noticed as well. The thesis starts with the introduction of the well known Client/Server architecture in INTERNET at present. And the goal of this thesis was posed after analysis of the problem and restriction of such architecture applied in information sharing system. Then the characteristic of P2P was analyzed, the difference from traditional C/S architecture compared, mainly applications of P2P recounted, status quo of correlative research in our country investigated. Through analyzing a series of different P2P models, the appropriate mode was chosen. And the design process and structure of the file sharing system based on this P2P model was expatiated, three components (Server, Listener and Browser) and the communication mechanism of them was discussed. At the end of the thesis, the implementation and test detail of this system was brought forth.