An Efficient Group Signatures Based on Discrete Logarithm

A group signature scheme allows a group member to sign a messageanonymously on behalf of the group. In case of a dispute, the groupmanager can reveal the actual identity of signer. To enhance theefficiency of group signature schemes, in this paper, we propose anefficient group signature scheme which adds some redundant bits toeach divided message block, to avoid the conspiracy attack. In ourscheme, the size of a signature is the same as that of an individualsignature and the signature verification process is simplified by agroup public key. The security of the proposed scheme is based onthe difficulty of computing the discrete logarithm modulo for acomposite number.