Abstract:

The (t,n) threshold ring signature can be generated by any t entities of n entities group on behalf of the whole group, while the actual signers remain anonymous. At present, the security of the identity based threshold ring signature schemes are almost proven under the random oracle model, while it may be not secure for those schemes under the random oracle model. There, it is meaningful to design threshold ring signature scheme in the standard model. This paper proposes a secure and efficient identitybased threshold ring signature scheme by using bilinear pairing technique, and proves that this scheme satisfies the existential unforgeability against adaptive chosen message and identity attacks in terms of the hardness of CDH problem in the standard model. Meanwhile, it is proved that the scheme satisfies the unconditional signer ambiguity.   

Key words: identity based cryptography;threshold ring signature;standard model;computational DiffieHellman problem