The Design And Implementation Of File Sharing System Based On Peer-to-Peer Network

Peer-to-Peer technology is a hot topic of current research in the field of computer network technologies. It broke the traditional network models, making the resource sharing between computer systems no longer needed the central server as a transit, so that sharing resource and exchanging information can be more directly. Peer-to-Peer technology can make full use of a large number of processing capacity, computing capacity, storage spaces in the network and so on, improve resource utilization significantly, it has developed rapidly in the field of VoIP, downloading, streaming media and coordinated computing. File sharing is a major application of P2P technology, as well as a power source of P2P development. As one of the main applications of Internet, P2P file sharing has much influence onto Internet usages and traffics. P2P technology has the characteristics of decentralization, scalability, and robustness, high performance/price ratio, broader prospects for applications, and so on. Currently the technology is constantly applied to the areas of military, business, government information. Additionally, IT companies are doing extensive research on this technology. It not only promoted the development of science and technology, but also has far-reaching effects on the ways of interaction among humans in society.This thesis firstly introduces the basic theory of P2P technology, the status of P2P file-sharing system, and by analyzing the P2P network topology, finds the type of the structure which is suitable for the system; and problems faced by file-sharing system are pointed out by analyzing the existing file-sharing system. System design requirements and model frame of file-sharing system in the model design of P2P network file sharing system are proposed. Otherwise, features and services of various layers are to be illustrated and present. Secondly, the main components in P2P file-sharing system as well as their roles and functions in the file-sharing system are put forward. Further, the thesis has mainly elaborated the development requirements of the file-sharing system and provided the system’s overall design flow chart and design class diagram of the server and the clients based on the understanding of P2P technology. At last, the system has been implemented by programming and each module functionality between the server-side and client-side and the interoperability among modules have been achieved.