A Structured Multisignature Scheme from the Gap Diffie-Hellman Group

In this paper, the authors propose a new structured multisignature scheme that considers the signing order among co-signers. The proposed scheme can resolve signing structures of serial, parallel, and the mix of them. Moreover, the size and the verification of a structured multisignature is the same as those of an individual signature generated by any co-signer. Arithmetically, the proposed scheme makes use of the Gap Diffie-Hellman (GDH) signature scheme recently presented by Boneh, Shacham, and Lynn. Due to the underlying GDH group, our scheme has the merits of simplicity in construction and efficiency in performance.