A Provably Secure Certificate Based Ring Signature Without Pairing

In Eurocrypt 2003, Gentry introduced the notion of certificate-based encryption. The merit of certificatebased encryption lies in implicit certificate and no private key escrow. This feature is desirable especially for the efficiency and the real spontaneity of ring signature, which involve a large number of public keys in each execution. In this paper, we propose an efficient certificatebased ring signature scheme which does not require any pairing computation. Furthermore, this scheme is proven secure under the Discrete Logarithm assumption in the random oracle model. To the best of authors’ knowledge, this is the first construction of certificate-based ring signature scheme in the literature that has such kind of feature.