A Review of Blockchain Consensus Algorithm Research

Abstract

Blockchain is a decentralized distributed ledger technology in which consensus algorithms ensure data consistency and system security among mutually untrusted nodes. The choice of a consensus algorithm significantly affects key performance indicators of a blockchain system, such as transaction throughput and energy consumption. This paper presents a systematic review of blockchain consensus algorithms. Based on their underlying principles, mainstream consensus algorithms are categorized into two major types: proof-based and voting-based mechanisms. Proof-based algorithms, such as Proof of Work (PoW) and Proof of Stake (PoS), rely on resource investment to obtain the right to produce blocks; voting-based algorithms, including Raft and Practical Byzantine Fault Tolerance (PBFT), achieve consensus through node collaboration and voting. This paper provides an in-depth analysis of nine representative consensus algorithms and compares them in terms of efficiency, scalability, fault tolerance, and complexity. Finally, the paper summarizes the current challenges and potential research directions in the field, offering theoretical support and reference for the design of future blockchain systems.