A versatile and modular consensus protocol
Achour Mostéfaoui, Sergio Rajsbaum, Michel Raynal · 2003
Investigates a modular and versatile approach to solve the consensus problem in asynchronous distributed systems in which up to f processes may crash (f<n/2), but equipped with appropriate oracles. It presents a generic protocol that proceeds by consecutive asynchronous rounds. Each round follows a "two-phase" pattern. The modularity and the versatility of the protocol appear at each phase of a round. The first phase is a selection phase that allows to use any combination merging random oracle, leader oracle and condition. Its aim is to ensure termination by allowing the processes to start the second phase with the same value. The aim of the second phase is to ensure that the agreement property cannot be violated. Its cost depends on the value of f: two communication steps when f<n/2, that reduce to a single communication step when f