P2p Network Trust Cloud Model Based On Interest Group

One of the most important applications of P2P technology is the P2P network, where there are no centralized servers, has caused constant public concern. However, with the expansion of the network, more and more malicious peers add into the network, makes greater security risks in the network. Studies show that the establishment of reasonable trust model can effectively solve the problem.After deep research into the related concept of P2P network and trust mechanisms, this paper proposed an interest group based trust cloud model--IGCMTrust. The proposed model evaluates the peer’s trust degree by benefiting from the idea that absolute priority is given to human’s direct experience in human psychological cognitive habits to judge, which reduces the computational complexity. This model also gives a method to compute the recommendation credibility, which reduces the risk of accepting false recommendation information. Further, two characteristic parameters of cloud model, entropy and hyper entropy, are used to introduce "behavioral uncertainty factor" to judge the peer’s degree of the behavioral fluctuation, and then, by positive and negative reward factors encouraging good peers and punishing malicious peers respectively. At the same time, by introducing "Topic Interest" and "Secondary Interest" to divide the interest groups, this model effectively solves the problems of excessive messages in P2P network and the asymmetric interest making it difficult to establish the direct trust relationship. Finally, through comparison between IGCMTrust model and PeerTrust、No-Trust model, experiments show that the proposed model can reduce the number of the messages in the network, and can resist the attacking of various types of the malicious peers.