An Efficient Fuzzy Identity-based Signature Scheme without Bilinear Pairings

Biometric-based signature is an emerging cryptographic primitive that allows a user with a biometric identity to produce a signature that can be verified successfully using another biometric identity if both biometric identities are within a predefined distance metric. Fuzzy identity-based signature is of particular value for biometric authentication, where biometric identifiers such as fingerprints, iris and voice are used in human identification. Unfortunately, constructions of fuzzy identity-based signature scheme so far are based on bilinear pairings that need costly operations. In this paper, we propose a new fuzzy identity-based signature scheme that does not depend on bilinear pairings. With both the running time and the size of the signature being saved greatly, our scheme is more practical than the previous related schemes for practical application. The proposed fuzzy identity-based signature scheme is proved to be existential unforgeability against adaptively chosen message attack under the standard discrete logarithm assumption in the selective-set model.