P2p Network Credibility Evaluation System Design

Nowadays, the Peer-to-Peer (P2P) is one of the most hotpots in the computer network, and it strongly affects the traditional network, which focuses on its content. While P2P network adopts a distributing network structure, and each peer is both client and server. This infrastructure is widely used in file-sharing, distributed computation, cooperation system, electrical business, deep search engine, etc. But P2P network is still evolution, it has not general standard. Its security should be paid special attention because of its distributed infrastructure. The P2P file-sharing system offers a way for users to exchange their resources easily, but the truthfulness of the resources cannot be guaranteed. The openness and anonymity character of P2P file-sharing permits each peer to join and leave the community, some vicious peers may harm the system, which enhances the unsafe probability in file-sharing, so it is necessary to take some measures to distinguish and reduce the effects of vicious peers. This paper presents a reputation evaluating system, which is based on the file content and peer behavior in P2P file-sharing network. This evaluating system can build an independent evaluation result for every file in P2P network so as to log the truthfulness of the file, and let other peers refer to the evaluation results. At the same time, the system can also log peer's behavior character, which include peer's reputation, the amount of sharing files, period of online time and bandwidth service. The other peers can refer to truthfulness and credibility on this peer's resources, and guide them to download the files. In order to reduce the effects of vicious peers, the reputation evaluating system can distinguish garbage from normal files, so it can ensure the truthfulness and efficiency of P2P file-sharing network. The reputation evaluating system also can limit the behavior of peer whose behavior is very bad or forbid it to join the community. This paper illustrates that the reputation evaluating system is valid and practical, and the simulating and test experiments proved that the approach achieved the desired goal.