A provable secure fuzzy identity based signature scheme

Abstract

To use biometrics identities in an identity based encryption system, Sahai and Waters first introduced the notion of fuzzy identity based encryption (FIBE) in 2005. Yang et al. extended it to digital signature and introduced the concept of fuzzy identity based signature (FIBS) in 2008, and constructed an FIBS scheme based on Sahai and Waters’s FIBE scheme. In this paper, we further formalize the notion and security model of FIBS scheme and propose a new construction of FIBS scheme based on bilinear pairing. The proposed scheme not only provides shorter public parameters, private key and signature, but also have useful structures which result in more efficient verification than that of Yang et al.’s FIBS scheme. The proposed FIBS scheme is proved to be existentially unforgeable under a chosen message attack and selective fuzzy identity attack in the random oracle model under the discrete logarithm assumption.