ID Based Signature Scheme from Strong RSA Assumption in the Standard Model

ID based cryptography is always the interested field in the cryptography research, since it has the advantage of eliminating user’s certificates, and the cost of certificate management is saved. Although many ID based cryptographic primitives have been proposed, most of them are constructed from bilinear pairing, and based on the hardness assumptions in bilinear pairing. Since pairing usually involves heavy computational costs, how to construct ID based cryptographic primitives without pairing is still a valuable issue in the cryptography. A few ID based signature schemes have been presented, however, some of them have not provided the security proof, and others can only be proved secure in the random oracle. There is still no true ID based signature schemes in the standard model. In this paper, an ID based signature scheme from Hohenberger and Waters signature is proposed, which can be proved weakly secure under the strong RSA assumption. Furthermore, with the help of Chameleon Hash function, the proposed scheme can be transformed into a provably secure scheme in the standard model. In the proposed scheme, the signature involves 2 elements in N*N, and the signing algorithm only needs 2 modular exponentiations.