Provably secure revocable ID-based signature in the standard model

A signature scheme is one of the important primitives in modern cryptography, which may offer functionalities of user identification, non-repudiation, and message authentication. With the advent of identity (ID)-based public key systems with bilinear pairings defined on elliptic curves, many ID-based signature schemes have been proposed. Like certificate-based public key systems, any ID-based public key system must provide a revocation method to revoke misbehaving users. There was little work on studying the revocation problem of ID-based public key systems, and no ID-based signature scheme deals with how to revoke the signing ability of misbehaving users. Quite recently, Tseng and Tsai presented a practical revocation mechanism using a public channel for ID-based public key systems. In this paper, we adopt Tseng and Tsai's revocation concept to define the new framework and security notions of revocable ID-based signature (RIBS) scheme and propose the first RIBS scheme in the standard model. Under the computational Diffie-Hellman assumption, we demonstrate that the proposed RIBS scheme is provably secure while remaining efficient for signing and verification as compared with previously proposed ID-based signature schemes.