Anonymous yet Traceable Strong Designated Verifier Signature

Abstract

In many privacy-preserving protocols, protection of the user’s identity, called anonymity, is a desirable feature. Another issue is that, if a signed document is leaked then anyone can be convinced of the authenticated data, which is strictly not allowed for sensitive data, instead the authentication only by a designated receiver is recommended. There are many scenarios in real life, for example e-auction, where both the functionalities– anonymity and designated verification are required simultaneously. For such an objective, in this paper we introduce a compact scheme of identity-based strong designated verifier group signature (ID-SDVGS) by combining the good features of strong designated verifier signature and group signature in ID-based setting. This scheme provides anonymity to the signer of a designated verifier signature with the feature of the revocation of signer’s identity in case of misuse or dispute. Moreover, our scheme fulfils all the security properties of the individual components. We have obtained an ID-based instantiation of the generic group signature given by Bellare et al. in Eurocrypt 2003, and have proposed our scheme on that framework. To the best of our knowledge, this is the first construction of ID-SDVGS. © 2018, Springer Nature Switzerland AG.