Robust forward-secure signature schemes with proactive security

Abstract

The secret key of a forward-secure signature scheme evolves at regular intervals, but the public key is fixed during the lifetime of the system. This paper enhances the security of Abdalla and Reyzin's forward-secure signature scheme via threshold and proactive mechanisms. In our threshold forward-secure signature scheme, we combine multiplicative and polynomial secret sharing schemes to form a threshold forward-secure signature scheme. We develop a special proof system to prove robustness of our scheme.