Blockchain Consensus Algorithms: A Survey
Xiaoman Li, QingHua Zhu, Naina Qi, Jinqiu Huang, Yong Yuan, Fei–Yue Wang
Abstract
Blockchain has received intensive interests in both academia and industries in recent years. As a key component of the blockchain architecture, consensus algorithm plays a critical role in maintaining such advantages as consistency, availability and fault tolerance for distributed systems, and thus can find a wide spectrum of potential application scenarios with success. In this paper, we surveyed the mainstream consensus algorithms systematically, which is classified into five categories according to its leader election model, i.e., election-based, proof-based, randomness-based, committee-based and hybrid. We discussed the recent research progresses in each of the five categories, and also presented the open issues and future research directions of consensus algorithms. This paper is targeted at providing useful guidance and reference for future innovation in blockchain.