Abstract: Trust management based on CA can not suit the Peer-to-Peer network of dynamic, symmetry and decentralization. The CMPJV is proposed to determine whether or not to permit one applicant to join the peer group by joint votes of all the peers in the peer group, and to initialize the applicant’s key attributes in the decentralized environment. The final result of joint votes is calculated by WCVTS, which introduces two factors: original role trust that permits peer to vote more precisely instead of yes or no, and role delegation ability that is used to limit the authorization scope horizontally and vertically. In addition, because any one peer is his own CA to issue his vote for the applicant, and CMPJV is one pure peer-to-peer group admission protocol , it can better overcome the inherent drawbacks of Client/Server. Finally, the running model’s analysis is used to verify its formal security.

Key words: P2P network, trust management, membership