Hidden Identity-Based Signatures

This paper introduces Hidden Identity-based Signatures (Hidden-IBS), a type of digital signatures that provide mediated signer-anonymity on top of Shamir’s Identity-based signatures. The motivation of our new signature primitive is to resolve an important issue with the kind of anonymity offered by “group signatures” where it is required that either the group membership list is public or that the opening authority is dependent on the group manager for its operation. Contrary to this, Hidden-IBS do not require the maintenance of a group membership list and they enable an opening authority that is totally independent of the group manager. As we argue this makes Hidden-IBS much more attractive than group signatures for a number of applications. In this paper, we provide a formal model of Hidden-IBS as well as two efficient constructions that realize the new primitive. Our elliptic curve construction that is based on the SDH/DLDH assumptions produces signatures that are merely half...

• Type: Conference
• Year: 2007
• Where: FC
• Authors: Aggelos Kiayias, Hong-Sheng Zhou
• Keywords: FC 2007, Identity-based Signatures, Opening Authority, Signatures