Research On Trust Model In P2P Network

With the rapid development of information technology, P2P has become the overwhelming technology for the internet as its advantage in cooperative working, data sharing and scale parallel computing.P2P network adopts a distributing network structure and every node is responsible for the client role and the server. However, the nature of openness, anonymity and loose-coupling relationship among peers in P2P systems make it an ideal environment for malicious users to spread unsolicited and harmful content, opening the door to abuses of the networks, so it is necessary to build up a rational trust model in P2P network.A new P2P network model named IGP2P (Interest Group P2P) has been presented which is based on the node with similar semantics and interest in the hybrid P2P network. IGP2P divided the P2P network into many groups according to the standard of user's interest. There is a central node to be responsible for the group. First the interest group model, organizational structure and the similarity between the nodes used to distinguish levels of loving was introduced in detail. In order to reducing the harm of the network by single point of failure, we introduced the Standby Managing Peer Strategy (SMP strategy) and on the node join and exit and treatment programs of failure. Finally we put forward search strategy on IGP2P, which includes group- in search and group-out search, and group-in search is the main search strategy. IGP2P also improves the node cache strategy, which not only improves the searching speed and successful rate, but also reduces the share of P2P network bandwidth and improve network stability.According to the analysis of advantages and disadvantages of existing local trust model and global trust model in this paper, trust model management IGTM, based on interest group of IGP2P network structure, is created by reference to process of trust establishment in real society and management of firms and cooperation between firms. There is in-group trust and inter-group trust in the P2P network based on interest group. In the group, the collection of historical transaction information, the integration of evaluator's personal information and interest similarity and recommended intensity factor between peers and the correction of evaluator's information formulate in-group trust. Between groups, inter-group trust can be done relying on historical transaction. Finally, the integration of in-group trust and inter-group trust result in overall trust, which serves as a trading decision.Through comparison among the IGTM and other recommendation-based turst model, it has been proved by the simulation result that the improved model has better performance in evaluation accuracy, security, resistance to attacking on the malicious peers and low operating expenses.