基于Client Puzzle的公有链接入控制模型

Client Puzzle Based Access Control Model in Public Blockchain

公有链无集中控制节点、去中心化和允许任意节点加入的特点使其拥有高效、低成本和高数据安全性的优势,但由于其允许任意节点接入,因此将增加公有链网络的脆弱性。基于Client Puzzle,提出一种节点接入控制模型CPACM(Client Puzzle based Access Control Model),使新节点接入公有链前利用算力进行工作量证明,完成工作量证明后才可接入公有链。该模型在维持公有链去中心化的同时,增加了接入控制。实验证明,该模型在不影响诚实节点加入的情况下,能以较高成功率限制低诚意节点和低算力节点的加入,并且能防止节点间的伙同,防范了恶意行为,提高了公有链网络的安全性。

Public blockchain characterizes non-centralization and decentration and allows any node to join,and thus possesses the advantages of high efficiency,low cost and high data security.However,that it allows any node to join increases the vulnerability of blockchain network.This paper proposed a Client Puzzle based access control model named CPACM.In this model,new nodes have to make use of computing power to conduct proof of work before joining the network.Only the successful nodes could join the public blockchain network.This model adopts access control when keeping public blockchain decentralizing.Experimental results show that the proposed model can restrict the low computing-power nodes and unfaithful nodes to access with high probability when not affecting the faithful nodes to access and prevent nodes collusion,thus preventing the malicious behaviors and improving the security of public blockchain.