Research Of Grouped P2P Topology Constructing And Access Control Technologies Based On Trust

P2P network has shown better performance in cooperative working,distributed data sharing and large scale concurrent computation,but there are many problems about manageability,incentive and security in P2P network:because of P2P network's characteristic of distribution,the management of peers can't be implemented effectively; the lack of incentive mechanism results in that the resources can't be shared reasonably; since the malicious activities have been more complex,single secure mechanism hasn't guarantee the security of P2P network effectively.Against the above aspects,this paper issues a grouped hybrid P2P network firstly, then studies the trust model and its implementation in topology constructing,access control technologies in the grouped hybrid P2P network.The detailed research work in this paper includes as below:(1) Aiming at the existent insufficiency of present hybrid P2P networks,a grouped hybrid P2P network(GHP2P) is designed.The network is composed of multiple groups, and each group is administrated by super-peers.Each peer in GHP2P initializes neighbor peers according to its interests.(2) A dynamic global trust model based on feedback(DGTrust) is issued to distinguish free-rider and different malicious peers effectively.This model evaluates peers' trustworthiness and service capability considering the time factor and punishment mechanism,while gives the request handling and response selection strategies based on trust.(3) A trust-based adaptive topology constructing protocol(TATCP) is issued.The importance of trust model in topology constructing is shown.Based on DGTrust,the protocol optimizes the topologies of normal-peer layer and super-peer layer in GHP2P.(4) Utilizing the flexibility of partition between role and authority in RBAC model,a layered access control model based on trust and role(TRGAC) in GHP2P is issued.The model authorizes the peer appropriate role according to the evaluation results of DGTrust and controls the access of peers having different role based on layered mechanism. The research has shown that,the combination of trust model,topology constructing technology and access control model could inspire peers to share resources in many ways as well as improve the security and manageability of P2P network greatly.