A New Blind Identity-Based Signature Scheme

Anonymity of consumers is an essential functionality that should be supported in any digital rights management system. Privacy protection is an important aspect for wider acceptance of consumers of DRM systems. The concept of a blind signature is one possible cryptographic solution, yet it has not received much attention in the identity-based setting. In the identity-based setting, the public key of a user is derived from his identity, thus simplifying certificates management process compared to traditional public key cryptosystems. In this paper, a new blind identity-based signature scheme based on bilinear pairings on elliptic curves is presented. The use of bilinear pairings over elliptic curves enables utilizing smaller key sizes, while achieving the same level of security compared to other schemes not utilizing elliptic curves. The correctness of the proposed scheme is validated and the proof of the blindness property is provided. Performance and security related issues are addressed.