An efficient revocable certificateless signature scheme

In traditional PKC, public keys of the users are essentially random string generated from random secret keys, thus, public key certificates are required to link the relations between user´s identities and their public keys. In ID-based cryptography, public keys are identities such as names, email address, and so on. It avoids the use of certificates which is a burden in traditional PKC. However, it exist key escrow problem. In a certificateless cryptographic system, it avoids the inherent key escrow in the ID-based crypto-system, and heavy certificate maintenance in the PKC system. For all we know, most of the existing certificateless signature schemes cannot realize the revocation of a signature. To overcome this issue, we put forward a novel revocable certificateless signature scheme under the standard security model in this paper. It can provide the revocation of a signature by publishing a value in the revocation list. And the scheme can be provably secure based on the standard computational Diffie-Hellman assumption.