Provably Secure Multisignatures in Formal Security Model and Their Optimality
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences
Formal security model of multisignatures
ISC'06 Proceedings of the 9th international conference on Information Security
On the security of probabilistic multisignature schemes and their optimality
Mycrypt'05 Proceedings of the 1st international conference on Progress in Cryptology in Malaysia
| Hi-index | 0.00 |
Up to present, proposed are many multi-signature schemes in which signers use respective moduli in the signature generation process. The FDH-based schemes are proposed by Mitomi et al. and Lysyanskaya et al.. The PSS-based schemes are proposed by Kawauchi et al. and Komano et al.. The FDH-based schemes have the advantage that the signature size is independent of the number of the signers. However, since the signature generation algorithm is deterministic, it has a bad reduction rate as a defect. Consequently, the signers must unfortunately use the keys large enough to keep the security. On the other hand, in the PSS-based schemes, good reduction rates can be obtained since the signature generation algorithms are probabilistic. However, the size of the random component shall overflow the security parameter, and thereby the signature size shall grow by the total size of the random components used the signers. That means, if the size of the random component is smaller, the growth of the signature size can be kept smaller. In this paper, we propose new probabilistic multi-signature scheme, which can be proven secure despite that smaller random components are used. We compare the proposed scheme and two existing schemes. Finally, we conclude that the proposed scheme is so-called optimal due to [3].