Recent Results on Fault-Tolerant Consensus in Message-Passing Networks

TL;DR

This survey reviews recent advances in fault-tolerant consensus in message-passing networks, covering new problem formulations, practical applications, and comparisons of systems like Paxos, Raft, and Bitcoin over the past decade.

Contribution

It categorizes recent results into new problem definitions and practical systems, providing a comprehensive overview of techniques and applications in fault-tolerant consensus.

Findings

Introduction of new consensus problem formulations

Analysis of practical systems like Paxos, Raft, and Bitcoin

Comparison of Byzantine and crash fault-tolerant systems

Abstract

Fault-tolerant consensus has been studied extensively in the literature, because it is one of the most important distributed primitives and has wide applications in practice. This paper surveys important results on fault-tolerant consensus in message-passing networks, and the focus is on results from the past decade. Particularly, we categorize the results into two groups: new problem formulations and practical applications. In the first part, we discuss new ways to define the consensus problem, which includes larger input domains, link fault models, different network models . . . etc, and briefly discuss the important techniques. In the second part, we focus on Crash Fault-Tolerant (CFT) systems that use Paxos or Raft, and Byzantine Fault-Tolerant (BFT) systems. We also discuss Bitcoin, which can be related to solving Byzantine consensus in anonymous systems, and compare Bitcoin with BFT systems and Byzantine consensus.