Re-Raft: An Improved Blockchain Consensus Algorithm with Enhanced Byzantine Resistance and Crash Tolerance

The traditional Raft consensus algorithm is widely used in private chains due to its crash-tolerant feature, but it cannot solve many problems caused by the malicious behaviour of Byzantine nodes. Based on an in-depth analysis of existing research results, this paper proposes a consensus algorithm based on the Raft algorithm with enhanced Byzantine resistance and crash tolerance: Re-Raft (Reliability-Raft), in order to solve the core problems of Byzantine nodes identity forgery and illegal replacement of leaders. A fault heartbeat logging mechanism is introduced to prevent Byzantine nodes from obtaining the majority of votes by broadcasting fault heartbeat logs; and a node reliability assessment algorithm is proposed to accurately assess the reliability of nodes by combining the continuity penalty weights and the time decay factor to reduce communication redundancy triggered by frequent node failures. The experimental results show that compared with the native Raft, the Re-Raft algorithm achieves a significant improvement in Byzantine fault-tolerance capability.