Traceable Signature: Better Efficiency and Beyond

In recent years one of the most active research areas in applied cryptography is the study of techniques for creating a group signature, a cryptographic primitive that can be used to implement anonymous authentication. Some variants of group signature, such as traceable signature, and authentication with variable anonymity in a trusted computing platform, have also been proposed. In this paper we propose a traceable signature scheme with variable anonymity. Our scheme supports two important properties for a practical anonymous authentication system, i.e., corrupted group member detection and fair tracing, which have unfortunately been neglected in most group signature schemes in the literature. We prove the new scheme is secure in the random oracle model, under the strong RSA assumption and the decisional Diffie-Hellman assumption.