A Content Authentication Scheme in Hybrid P2P Network

In P2P file sharing network, the replicas of the same content are stored at various locations .This allows content to be accessed even when some nodes are disconnected. However, this high degree of redundancy implies that it is necessary to find some security mechanisms in order to avoid attacks based on content pollution. In this paper, we propose a content authentication method for hybrid P2P network. For it is unrealistic to apply a trusted third party in P2P network , our scheme relies on a set of up-layer nodes playing the role of a certificate authority in hybrid P2P network . In our scheme, we use Merkle hash tree and certificateless threshold ring signature to authenticate the integrality of content. Foremost, the threshold ring signature based on certificateless public key cryptology scheme is firstly mentioned in this paper. Finally, we solve the problems about fault tolerant storage the authentication information and the digital signature resists replay attack.