A New Threshold Group Signature Scheme Based on Discrete Logarithm Problem

The threshold group signature is an important kind of signature. So far, many threshold group signature schemes have been proposed, but most of them suffer from conspiracy attack and are insecure. In this paper, based on the discrete logarithm problem and the group signature model of Camenisch and Groth [6], a secure threshold group signature scheme is proposed. The scheme is not only threshold-signing, but also threshold-verifying. Performances analysis shows that it can not only satisfy the properties of threshold group signatures , but also withstand the conspiracy attack.