Group Signature System Using Multivariate Asymmetric Cryptography

Abstract

This chapter presents a new group signature scheme using multivariate asymmetric cryptography. Compared with the exited signature schemes, the proposed scheme is applicable to e-voting schemes and can convince the requirements of e-voting schemes because it has two important characteristics, traceability and unlinkability. Traceability denotes that a group director cannot open the signature alone. He has to collaborate with a verifier to disclose an identity of the signer. Unlinkability denotes that the group signature can be split accordance to time durations. Then signatures are linkable in the same time range but un-linkable between dissimilar time periods. Therefore, the count authority can notice the double votes prior to opening them. Thus, there are two features in the proposed signature for count and supervision authority. Also, the size of signatures and the calculation overhead are private from the group members in the proposed scheme. So, it is efficient for large groups.