Reusable Time-Lines and Applications

We introduce the notion of a reusable time-line, a cryptographic primitive for robust timed release of information with lowered session costs. We discuss how it can be used to lower costs in existing timed applications. We take advantage of its robustness properties to solve a problem not addressed previously, namely, the timed release of standard digital signatures, and demonstrate how to achieve a "transparent" timed release of RSA, DSS and Schnorr signatures.