The best of both worlds: A hybrid approach to solve consensus

It is now well recognized that the consensus problem is a fundamental problem when one has to implement fault-tolerant distributed services in asynchronous distributed systems prone to process crash failures. This paper considers the binary consensus problem in such a system. Following an approach investigated by Aguilera and Toueg, it proposes a simple binary consensus protocol that combines failure detection and randomization. This protocol terminates deterministically when the failure detection mechanism works correctly; it terminates with probability 1, otherwise. A performance evaluation of the protocol is also provided. Last but not least, it is important to note that the proposed protocol is both efficient and simple. Additionally it can be simplified to give rise either to a deterministic failure detector-based consensus protocol or to a randomized consensus protocol