A Rigorous Approach to Key-Escrow (Extended Abstract)
Joe Kilianl, Tom Leighton · 1995
Recently, there has been a surge of interest in key-escrow systems, from the popular press to the highest levels of governmental policy-making. Unfortunately, the field of key-escrow has very little rig- orous foundation, leaving open the possibility of a catastrophic security failure. As an example, we demonstrate a critical weakness in Micali's Fair Public Key Cryptosystem (FPKC) protocols. Micali's FKPC pro- tocols have been licensed to the United States Government for use with the Clipper project, and were considered to be a leading contender for software-based key escrow. In the paper, we formally model both the attack and what it means to defend against the attack, and we present an alternative protocol with more desirable security properties.