Abstract: An efficient threshold signature scheme based on the difficulty of discrete logarithm problem and secret sharing method was proposed. Distribution Center(ID) shares the signature secret key with group members by the method of optional quotient.ID generates threshold Signature according to the sharing signatures after the identity and correctness verification.The identity and time stamp of the sharing signature members are recorded in the database prepared for arbitrating the dispute in the future. The analysis from correctness, security and efficiency shows that the proposed scheme is effective and secure.

Key words: Threshold group signature, Secret sharing, Digital signature