Abstract: Blockchain is the core supporting technology of the digital cryptocurrency system represented by Bitcoin, which can bring profound changes to finance, economy, science and technology and even politics. It integrates distributed systems, cryptography, game theory and other disciplines have established a new type of trust model. As the core of the blockchain technology, the consensus mechanism plays an important role in maintaining the stable operation of the blockchain system and mutual trust between nodes. In recent years, with the hot of block chain technology, consensus algorithm has made considerable progress. This article first analyzes the application of the consensus mechanism and the problems to be solved by analyzing the core technology of the blockchain.Then we introduce consensus mechanism current representative and thoroughly analyzed it. We hope to provide ideas and lessons for the study of consensus mechanisms.

Key words: Blockchain, Bitcoin, Cryptography, Consensus Mechanism, Distributed System

摘要： 区块链是以比特币为代表的数字加密货币体系的核心支撑技术，可以为金融、经济、科技甚至政治等领域带来深刻变革。它融合了分布式系统、密码学、博弈论等学科建立了一种新型的信任模型。共识机制作为区块链技术的核心，有着维护区块链系统稳定运行和节点相互信任的重要作用。近年来随着区块链技术的火热，共识算法较之前有了长足进步。本文首先通过分析区块链的核心技术引出共识机制的应用场景和要解决的问题，随后深入介绍了共识机制发展到目前为止代表性的算法并进行分析，希望能对共识机制的研究提供思路和借鉴。

关键词: 区块链, 比特币, 密码学, 共识机制, 分布式系统