An Agile P2p Trust Model Based On Interest Group

Peer-to-peer (referred to as P2P) is a new computing model which demands logical reciprocal between peers. Compared with traditional network based on the C/S (Client/Server) model, peers in P2P network are on an equal status. It adheres to nodes in the initiative. When node provides services for other nodes, it also gets services provided by others. When content storage center has moving towards end-users, P2P technology, with its deployment of flexible and low-cost, is widely and successfully spreading.However, essential characteristics of P2P network, such as network openness, node anonymity and autonomy, easily make infringement of intellectual property rights and dissemination of virus, garbage data, and fake file. What Free Riding actions are widely spreading is not only reduce performance of P2P network, but also increase the vulnerability of the system. Although distributed trust model doesn't resolve all of P2P security issues, it no doubt makes these issues under control in an extent. Adding an effective trust model, P2P network can improve the availability so that it leads to a sound development.Facing with the current trust model contradiction of scale and computation, with the idea of human society establishment, a P2P trust model based on interest group is proposed. Based on the nodes with semantic similarity gathered together, the model will have the same or similar interest nodes to join the same interest groups. The nodes in same group are equal, autonomy and have frequent transactions between peers. Each peer with best performance should be elected as a leader, who is responsible for dynamic join and quit of ordinary peers. 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 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.The simulation shows that the model, which can effectively improve the transaction rate and restrain malicious slander, runs safely. However, there are still shortcomings in the model, which need further research and improvement.