Forward-Secure Traceable Ring Signature

A traceable ring scheme is a ring signature except that it can restrict "excessive" anonymity. The traceable ring signature has a tag that consists of a list of ring members and an issue that refers to, for instance, a social affair or an election. A ring member can make any signed but anonymous opinion regarding the issue, but only once (per tag). The traceable ring signature can suit to many applications, such as an anonymous voting on a BBS, a dishonest whistle-blower problem, and unclonable group identification. In this paper, we suggest solutions to the key exposure problem in traceable ring signature. We propose the first forward secure traceable ring signature scheme and we prove its security in random oracle model.