A Fully Distributed Proactively Secure Threshold-Multi-signature Scheme

Threshold-multisignature schemes combine the properties of threshold group-oriented signature schemes and multisignature schemes to yield a signature scheme that allows a threshold (t) or more group members to collaboratively sign an arbitrary message. In contrast, to threshold group signatures, the individual signers do not remain anonymous, but are publicly identifiable from the information contained in the valid threshold-multisignature. The main objective of this paper is to propose such a secure and efficient threshold-multisignature scheme. The paper uniquely defines the fundamental properties of threshold-multisignature schemes and shows that the proposed scheme satisfies these properties and eliminates the latest attacks to which other similar schemes are subject.