Design of a Private Credentials Scheme Based on Elliptic Curve Cryptography

Credential systems are attracting more and more attention, as privacy infringement becomes a major issue in Internet based transactions. Private credentials offer authentication and authorization based on the attributes possessed by an user, rather than the identity of the user. They also satisfy properties such as unlinkability, unforgeability, property sharing resistance, confidentiality and selective disclosure of attributes. In this paper, a scheme of private credentials is presented, which is redefined in terms of elliptic curve cryptography. Elliptic curve arithmetic reduces the modular exponentiation operation to multiplication operation within a group. Here elliptic curve defined over a prime field Fq is chosen. The basis of the scheme is ECDLREP function i.e. elliptic curve discrete logarithm representation function. Thus, this scheme aims to extract the promising features of private credentials with the efficiency of elliptic curve cryptography.