With the rapid development of blockchain technology,more and more people are paying attention to the consensus mechanism of blockchain.Practical Byzantine Fault Tolerance(PBFT),as the first efficient consensus algorit...With the rapid development of blockchain technology,more and more people are paying attention to the consensus mechanism of blockchain.Practical Byzantine Fault Tolerance(PBFT),as the first efficient consensus algorithm solving the Byzantine Generals Problem,plays an important role.But PBFT also has its problems.First,it runs in a completely closed environment,and any node can't join or exit without rebooting the system.Second,the communication complexity in the network is as high as O(n2),which makes the algorithm only applicable to small-scale networks.For these problems,this paper proposes an Optimized consensus algorithm,Excellent Practical Byzantine Fault Tolerance(EPBFT),in which nodes can dynamically participate in the network by combining a view change protocol with a node's add or quit request.Besides,in each round of consensus,the algorithm will randomly select a coordination node.Through the cooperation of the primary and the coordination node,we reduce the network communication complexity to O(n).Besides,we have added a reputation credit mechanism and a wrong node removal protocol to the algorithm for clearing the faulty nodes in time and improving the robustness of the system.Finally,we design experiments to compare the performance of the PBFT and EPBFT algorithms.Through experimental,we found that compared with the PBFT algorithm,the EPBFT algorithm has a lower delay,communication complexity,better scalability,and more practical.展开更多
共识算法是一种用于确保区块链网络中所有节点达成一致的方法,常见的有工作量证明(Proof-of-Work,PoW)和权益证明(Proof of Stake,PoS)等,共识机制的优劣影响着区块链系统的性能。为了解决现有区块链共识算法存在的吞吐量较小、时延较...共识算法是一种用于确保区块链网络中所有节点达成一致的方法,常见的有工作量证明(Proof-of-Work,PoW)和权益证明(Proof of Stake,PoS)等,共识机制的优劣影响着区块链系统的性能。为了解决现有区块链共识算法存在的吞吐量较小、时延较长等问题,对区块链中实用拜占庭容错(PBFT)算法进行改进,引入基于Bayes理论的动态信任模型(Dynamic Trust Model),通过节点信任机制改变节点在共识轮中的信任度,并按照信任度进行分组等操作,在保证PBFT稳定性的同时提高了系统可扩展性,且完善了网络节点的加入退出机制,使得网络可拓展性得到提高。通过实验测试,相比传统PBFT,改进后的算法在吞吐量上有25%的提升,在节点数量达到50的情况下时延只有PBFT的一半,所提方法的这两项指标相比HotStuff算法和Paxos算法也有20%~30%的提升。展开更多
There has been significant recent research on secure control problems that arise from the open and complex realworld industrial environments.This paper focuses on addressing the issue of secure consensus control in mu...There has been significant recent research on secure control problems that arise from the open and complex realworld industrial environments.This paper focuses on addressing the issue of secure consensus control in multi-agent systems(MASs)under malicious attacks,utilizing the practical Byzantine fault tolerance(PBFT)and Raft consensus algorithm in blockchain.Unlike existing secure consensus control algorithms that have strict requirements for topology and high communication costs,our approach introduces a node grouping methodology based on system topology.Additionally,we utilize the PBFT consensus algorithm for intergroup leader identity verification,effectively reducing the communication complexity of PBFT in large-scale networks.Furthermore,we enhance the Raft algorithm through cryptographic validation during followers’log replication,which enhances the security of the system.Our proposed consensus process not only identifies the identities of malicious agents but also ensures consensus among normal agents.Through extensive simulations,we demonstrate robust convergence,particularly in scenarios with the relaxed topological requirements.Comparative experiments also validate the algorithm’s lower consensus latency and improved efficiency compared to direct PBFT utilization for identity verification and classical secure consensus control method mean subsequence reduced(MSR)algorithm.展开更多
The traditional Practical Byzantine Fault Tolerance(PBFT)approach suffers from three critical deficiencies:arbitrary primary node election,excessive network transmission overhead,coupled with the absence of node incen...The traditional Practical Byzantine Fault Tolerance(PBFT)approach suffers from three critical deficiencies:arbitrary primary node election,excessive network transmission overhead,coupled with the absence of node incentive mechanisms.To address these issues,this study proposes a refined PBFT strategy utilizing dual scoring(Double Scoring Practical Byzantine Fault Tolerance,DS-PBFT).The algorithm innovatively combines hardware performance evaluation with a dual-dimensional node scoring system.The algorithm first employs bucket sorting technology to quantitatively evaluate node hardware resources,followed by constructing a comprehensive scoring model through credit values and recommendation values.According to the scoring outcomes,the framework hierarchically divides nodes into primary node,follower node and backup nodes groups in a 1:4:5 ratio,substantially decreasing the quantity of nodes involved in consensus.Additionally,this approach streamlines the Commit-Reply stages within the consistency protocol,substantially reducing communication overhead.Experimental validation demonstrates that DS-PBFT maintains security while achieving notable improvements in consensus efficiency,significant reductions in communication costs,and enhanced defense capabilities against malicious nodes.展开更多
The PBFT (Practical Byzantine Fault Tolerance, PBFT) consensus algorithm, which addressed the issue of malicious nodes sending error messages to disrupt the system operation in distributed systems, was challenging to ...The PBFT (Practical Byzantine Fault Tolerance, PBFT) consensus algorithm, which addressed the issue of malicious nodes sending error messages to disrupt the system operation in distributed systems, was challenging to support massive network nodes, the common participation over all nodes in the consensus mechanism would lead to increased communication complexity, and the arbitrary selection of master nodes would also lead to inefficient consensus. This paper offered a PBFT consensus method (Role Division-based Practical Byzantine Fault Tolerance, RD-PBFT) to address the above problems based on node role division. First, the nodes in the system voted with each other to divide the high reputation group and low reputation group, and determined the starting reputation value of the nodes. Then, the mobile node in the group was divided into roles according to the high reputation value, and a total of three roles were divided into consensus node, backup node, and supervisory node to reduce the number of nodes involved in the consensus process and reduced the complexity of communication. In addition, an adaptive method was used to select the master nodes in the consensus process, and an integer value was introduced to ensure the unpredictability and equality of the master node selection. Experimentally, it was verified that the algorithm has lower communication complexity and better decentralization characteristics compared with the PBFT consensus algorithm, which improved the efficiency of consensus.展开更多
基金This research was supported by Key Projects of the Ministry of Science and Technology of the People’s Republic of China(2018AAA0102301)Project of Hunan Provincial Science and Technology Department(2017SK2405)CERNET Innovation Project(NGII20170715),(NGII20180902).
文摘With the rapid development of blockchain technology,more and more people are paying attention to the consensus mechanism of blockchain.Practical Byzantine Fault Tolerance(PBFT),as the first efficient consensus algorithm solving the Byzantine Generals Problem,plays an important role.But PBFT also has its problems.First,it runs in a completely closed environment,and any node can't join or exit without rebooting the system.Second,the communication complexity in the network is as high as O(n2),which makes the algorithm only applicable to small-scale networks.For these problems,this paper proposes an Optimized consensus algorithm,Excellent Practical Byzantine Fault Tolerance(EPBFT),in which nodes can dynamically participate in the network by combining a view change protocol with a node's add or quit request.Besides,in each round of consensus,the algorithm will randomly select a coordination node.Through the cooperation of the primary and the coordination node,we reduce the network communication complexity to O(n).Besides,we have added a reputation credit mechanism and a wrong node removal protocol to the algorithm for clearing the faulty nodes in time and improving the robustness of the system.Finally,we design experiments to compare the performance of the PBFT and EPBFT algorithms.Through experimental,we found that compared with the PBFT algorithm,the EPBFT algorithm has a lower delay,communication complexity,better scalability,and more practical.
文摘共识算法是一种用于确保区块链网络中所有节点达成一致的方法,常见的有工作量证明(Proof-of-Work,PoW)和权益证明(Proof of Stake,PoS)等,共识机制的优劣影响着区块链系统的性能。为了解决现有区块链共识算法存在的吞吐量较小、时延较长等问题,对区块链中实用拜占庭容错(PBFT)算法进行改进,引入基于Bayes理论的动态信任模型(Dynamic Trust Model),通过节点信任机制改变节点在共识轮中的信任度,并按照信任度进行分组等操作,在保证PBFT稳定性的同时提高了系统可扩展性,且完善了网络节点的加入退出机制,使得网络可拓展性得到提高。通过实验测试,相比传统PBFT,改进后的算法在吞吐量上有25%的提升,在节点数量达到50的情况下时延只有PBFT的一半,所提方法的这两项指标相比HotStuff算法和Paxos算法也有20%~30%的提升。
基金supported by the Fundamental Research Funds for the Central Universities(NS2024021)the Science and Technology Development Fund of Macao SAR(0145/2023/RIA3,0093/2023/RIA2,0050/2020/A1)the National Natural Science Foundation of China(62103411).
文摘There has been significant recent research on secure control problems that arise from the open and complex realworld industrial environments.This paper focuses on addressing the issue of secure consensus control in multi-agent systems(MASs)under malicious attacks,utilizing the practical Byzantine fault tolerance(PBFT)and Raft consensus algorithm in blockchain.Unlike existing secure consensus control algorithms that have strict requirements for topology and high communication costs,our approach introduces a node grouping methodology based on system topology.Additionally,we utilize the PBFT consensus algorithm for intergroup leader identity verification,effectively reducing the communication complexity of PBFT in large-scale networks.Furthermore,we enhance the Raft algorithm through cryptographic validation during followers’log replication,which enhances the security of the system.Our proposed consensus process not only identifies the identities of malicious agents but also ensures consensus among normal agents.Through extensive simulations,we demonstrate robust convergence,particularly in scenarios with the relaxed topological requirements.Comparative experiments also validate the algorithm’s lower consensus latency and improved efficiency compared to direct PBFT utilization for identity verification and classical secure consensus control method mean subsequence reduced(MSR)algorithm.
文摘The traditional Practical Byzantine Fault Tolerance(PBFT)approach suffers from three critical deficiencies:arbitrary primary node election,excessive network transmission overhead,coupled with the absence of node incentive mechanisms.To address these issues,this study proposes a refined PBFT strategy utilizing dual scoring(Double Scoring Practical Byzantine Fault Tolerance,DS-PBFT).The algorithm innovatively combines hardware performance evaluation with a dual-dimensional node scoring system.The algorithm first employs bucket sorting technology to quantitatively evaluate node hardware resources,followed by constructing a comprehensive scoring model through credit values and recommendation values.According to the scoring outcomes,the framework hierarchically divides nodes into primary node,follower node and backup nodes groups in a 1:4:5 ratio,substantially decreasing the quantity of nodes involved in consensus.Additionally,this approach streamlines the Commit-Reply stages within the consistency protocol,substantially reducing communication overhead.Experimental validation demonstrates that DS-PBFT maintains security while achieving notable improvements in consensus efficiency,significant reductions in communication costs,and enhanced defense capabilities against malicious nodes.
文摘The PBFT (Practical Byzantine Fault Tolerance, PBFT) consensus algorithm, which addressed the issue of malicious nodes sending error messages to disrupt the system operation in distributed systems, was challenging to support massive network nodes, the common participation over all nodes in the consensus mechanism would lead to increased communication complexity, and the arbitrary selection of master nodes would also lead to inefficient consensus. This paper offered a PBFT consensus method (Role Division-based Practical Byzantine Fault Tolerance, RD-PBFT) to address the above problems based on node role division. First, the nodes in the system voted with each other to divide the high reputation group and low reputation group, and determined the starting reputation value of the nodes. Then, the mobile node in the group was divided into roles according to the high reputation value, and a total of three roles were divided into consensus node, backup node, and supervisory node to reduce the number of nodes involved in the consensus process and reduced the complexity of communication. In addition, an adaptive method was used to select the master nodes in the consensus process, and an integer value was introduced to ensure the unpredictability and equality of the master node selection. Experimentally, it was verified that the algorithm has lower communication complexity and better decentralization characteristics compared with the PBFT consensus algorithm, which improved the efficiency of consensus.
