Abstract:

Delegated Proof of Stake （DPoS）， recognized as a mainstream consensus mechanism， encounters key problems including time-consuming election process， lack of active node participation in voting， and difficulties in handling malicious nodes， impeding its rapid development. In response to these problems， a credit-based committee consensus mechanism， Proof of Luck and Credit （PoLaC）， was proposed. Firstly， credit value was served as the evaluation criterion for nodes’ historical behaviors， and nodes with high credit value were selected as committee members， thereby simplifying the election process significantly. Secondly， the concept of lucky value was introduced to enhance the successful election probabilities for ordinary nodes， thereby stimulating the participation of ordinary nodes in network consensus. Finally， a delayed forking method was employed to rectify the behavior of malicious nodes. Experimental results demonstrate that in terms of consensus communication overhead， PoLaC network has 30% less communication overhead than DPoS network with 50% voting intention. In terms of low-weighted node revenue， revenues in PoLaC network are three times higher than those in DPoS network. In terms of the percentage of malicious nodes in the committee， during the credit stabilization period， the number of malicious nodes in PoLaC network’s committee is approximately one-fifth of those in DPoS. Compared to other similar credit-based consensus mechanisms， PoLaC exhibits certain advantages in network communication overhead， node activity， and malicious node handling.

Key words: blockchain, consensus mechanism, committee consensus, credit election, Delegated Proof of Stake (DPoS)

摘要：

授权股权证明（DPoS）作为主流共识机制的一种，选举过程耗时长、节点投票不积极和恶意节点难处理的核心问题制约着它的快速发展。针对上述问题，提出一种基于信誉的委员会共识机制——幸运信誉证明（PoLaC）。首先，将信誉值作为节点历史行为的评估标准，并选择高信誉节点作为委员会成员，从而极大地简化选举流程；其次，引入幸运值概念来提高普通节点竞选成功的概率，从而激励普通节点参与网络共识；最后，采取延迟分叉的方式修正恶意节点的行为。实验结果表明，在共识通信量方面，投票意愿为50%时，PoLaC网络比DPoS网络的共识通信量少30%；在低权重节点收益方面，PoLaC网络的收益是DPoS的3倍；在委员会恶意节点占比方面，进入信誉稳定期的PoLaC网络的委员会恶意节点数约为DPoS的1/5；而相较于其他同类信誉共识机制，PoLaC在网络通信量、节点活跃度以及恶意节点处理方面均具有一定优势。

关键词: 区块链, 共识机制, 委员会共识, 信誉选举, 授权股权证明