Agreement without knowing everybody: a first step to dynamicity

Abstract

We study in this paper the consensus problem in asynchronous models where the set of participating processes is not known. We prove that in this model the consensus is impossible to be solved even if no process may crash. We prove that the asynchronous model augmented with failure detector Σ, which enables to realize a quorum, is sufficient to circumvent this impossibility result. For this, we present an algorithm solving the consensus problem in this model.