Overview of Blockchain Consensus Algorithms

Consensus algorithm not only maintains the stability and security of distributed system, but also is the key technology in the development direction of blockchain.With the rapid development of blockchain technology, the research of consensus algorithm has attracted more and more attention and favor of researchers.Nowadays, choosing an appropriate consensus algorithm in different application scenarios is a selective problem that researchers have to face.Starting from the types of service object nodes, this paper classifies the consensus algorithm into three categories: public chain, alliance chain and private chain.Based on these three categories, this paper expounds the basic principles of some mainstream and some new blockchain consensus algorithms, a total of 9 consensus algorithms, and evaluates the performance of these 9 consensus algorithms from three aspects: decentralization, security and scalability.This paper also analyzes and summarizes the advantages and disadvantages of the relevant algorithms, an