A Tradeoff between Safety and Liveness for Randomized Coordinated Attack

Abstract

We study randomized, synchronous protocols for coordinated attack. Such protocols trade off the number of rounds (N), the worst-case probability of disagreement (U), and the probability that all generals attack (ℒ). We prove a nearly tight bound on the tradeoff between ℒ and U (ℒ/U≤N) for a strong adversary that destroys any subset of messages. Our techniques may be useful for other problems that allow a non-zero probability of disagreement © 1996 Academic Press, Inc.