针对Raft算法中的拜占庭容错问题，提出结合BLS签名的拜占庭容错（RaftByzantine fault tolerance，RBFT）算法.首先，利用BLS签名实现阈值签名，将投票过程转化为阈值签名过程，并将该过程与Raft算法的AppendEntries消息和RequestVote消息结合，尽可能地减弱容错过程对共识效率的影响；其次，通过增量哈希引入安全状态，保证了日志的不可篡改性；接着引入客户端对Leader节点的动态监控，以避免拜占庭Leader节点消极反馈的发生，进一步保证了算法的活性；最后，由本地多节点仿真实验表明：RBFT算法有效提升了数据吞吐量和可拓展性，并降低了交易延迟.
Aiming at the problem of Byzantine fault tolerance (BFT) in the Raft algorithm, a Raft Byzantine fault tolerance (RBFT) algorithm combined with BLS signature is proposed. First, it uses BLS signatures to implement threshold signatures, converts the voting process into a threshold signature process, and combines this process with the Raft algorithm's AppendEntries message and RequestVote message to minimize the impact of the fault-tolerant process on consensus efficiency. Second, it introduces a safe status through the incremental Hash value to ensure the log's tamper-resistibility. Then it provides dynamical monitoring on the leader node so as to avoid the possible negative feedback of Byzantine leader and ensure the liveness of the algorithm. Finally, local multi-node simulation experiments show that the RBFT algorithm could improve the throughput and scalability, and reduce the latency of transactions effectively.
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