基于二项交换林和HotStuff的改进共识算法

针对区块链中拜占庭容错类的共识机制存在通信复杂度高、视图切换复杂以及扩展性差的问题，提出了一种基于二项交换林和HotStuff的改进共识算法，即增强HotStuff（HSP）共识算法。为实现签名批量验证和签名聚合，采用了BLS签名算法；为降低系统的通信复杂度，采用了门限签名技术；为降低视图切换时的通信复杂度，共识过程采用了三阶段确认方式；为减少主副节点间的通信次数并降低主节点聚合签名的压力，采用了改进的二项交换林技术。测试结果表明，HSP共识算法在系统节点总数为64且请求和响应均为256字节的情况下，吞吐量较HotStuff共识机制提升了33.8%，共识延迟缩短了16.4%。HSP共识算法在节点多的情况下，具有较好的性能。

Improved consensus algorithm based on binomial swap forest and HotStuff

Aiming at the problems of Byzantine Fault Tolerant （BFT） consensus mechanisms in the blockchain such as high communication complexity， complex view change and poor scalability， a consensus algorithm based on binomial swap forest and HotStuff named HSP （HotStuff Plus） consensus algorithm was proposed. In order to realize signature batch verification and signature aggregation， the Boneh-Lynn-Shacham （BLS） signature algorithm was adopted； in order to reduce the communication complexity of the system， threshold signature technology was adopted； in order to reduce the communication complexity during view change， the consensus process adopted a three-phase confirmation method； in order to reduce the number of communications between the primary and secondary nodes and reduce the pressure on the primary node when aggregating signatures， an improved binomial swap forest technology was adopted. Test results show that when the total number of system nodes is 64 and the request and reply are both 256 bytes， the throughput of HSP consensus algorithm is 33.8% higher than that of HotStuff consensus mechanism， and the consensus delay of HSP consensus algorithm is 16.4% lower than that of HotStuff consensus mechanism. It can be seen that HSP consensus algorithm has better performance when the number of nodes is large.