Randomized Byzantine Agreement

A randomized model of distributed computation was recently presented by Rabin [ 81. This model admits a solution to the Byzantine Agreement Problem for systems of n asynchronous processes where no more than t are faulty. The algorithm described by Rabin produces agreement in an expected number of rounds which is a small constant independent of n and t. Using the same model, we present an algorithm of similar complexity which is able to tolerate a greater portion of malicious processes. The algorithm is also applicable, with minor changes, to systems of synchronous processes.