Consensus and Membership in Synchronous and Asynchronous Distributed Systems
Alessandro Galleni, David Powell · 1995
This paper surveys two fundamental agreement problems that must be solved in dependable distributed systems. In the consensus problem, processes need to reach a common decision despite failures. In the membership problem, agreement must be reached concerning the history of groups of correct processes that exist over time, as well as on the membership of each group. The exact definitions of these problems and algorithms for solving them depend on the assumptions that are made about process and communication failures. In this paper, we consider the existing literature on consensus and membership protocols designed according to various assumptions and discuss the advantages and drawbacks of the different approaches.