Credibility Problem In The P2p Network

P2P network develops quickly, while it still exists hidden trouble in security. Traditional concentrating trust mechanism no longer adapts to P2P system. The new mechanism of trust is needed to enforce the reliability in P2P networks, and thus the research of the reputation degree looks quite important.As an important portion of the trust mechanism, reputation model emphasizes the member's trust of each other and the authenticity of data. So as to insure peers' use of networks safely, reputation model needs to control improper manners effectively in communication, encourage peers to behave perfectly, and therefore prompt to exchange successfully on Internet.Several present reputation models mostly have a complicated structure . A new reputation model is provided in the paper , which has a simple structure, easily to control and maintain, more fit to trade on Internet. Its essential ideal is: Reputation degree among peers is based on co-exchange peers' history records, reputation sever take charge of calculation and storage of globe reputation value, and then peers' local reputation value is calculated by itself, which exchange to others, and calculated the final reputation value of exchange-node according its formula, so that to provide an important reference on whether to trade or not.