Threshold group signature scheme with mandatory signature privilege subsets
存在可实施强制签名特权集的门限群签名方案*

To the threshold group signature schemes with privilege subsets, if it want to produce effective group signature, it must achieve multiple threshold conditions, as long as one of the threshold conditions did not reach the group signature cannot produce, which greatly reduces the flexibility of this scheme. To solve the problem, made use of ELGamal encryption method, this paper put forward a signature scheme which could be either mandatory to implement or common to implement. The analysis results show that the theme has high flexibility, practicability and satisfies the properties of traceability, anonymity and so on. In addition, this paper analyzed the security of this scheme and proved that this scheme was secure in discrete logarithm assumption premise.