Distributed Agreement in the Presence of Processor and Communication Faults

Abstract

A model of distributed computation is proposed in which processes may fail by not sending or receiving the messages specified by a protocol. The solution to the Byzantine Generals Problem for this model is presented. Our algorithm exhibits early-stopping under conditions of less than maximum failure and is as efficient as the algorithms developed for the more restrictive crash-fault model in terms of time, message, and bit complexity. We show extant models to under-estimate resiliency when faults in the communication medium are considered; the model of this paper is more accurate in this regard.