Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniqu...Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.展开更多
The security problems of wireless sensor networks (WSN) have attracted people’s wide attention. In this paper, after we have summarized the existing security problems and solutions in WSN, we find that the insider at...The security problems of wireless sensor networks (WSN) have attracted people’s wide attention. In this paper, after we have summarized the existing security problems and solutions in WSN, we find that the insider attack to WSN is hard to solve. Insider attack is different from outsider attack, because it can’t be solved by the traditional encryption and message authentication. Therefore, a reliable secure routing protocol should be proposed in order to defense the insider attack. In this paper, we focus on insider selective forwarding attack. The existing detection mechanisms, such as watchdog, multipath retreat, neighbor-based monitoring and so on, have both advantages and disadvantages. According to their characteristics, we proposed a secure routing protocol based on monitor node and trust mechanism. The reputation value is made up with packet forwarding rate and node’s residual energy. So this detection and routing mechanism is universal because it can take account of both the safety and lifetime of network. Finally, we use OPNET simulation to verify the performance of our algorithm.展开更多
To keep open network more efficacious and secure, it is necessary that a nice trust model and method of trust management must be developed. The reason why traditional trust models are incomplete in their function to m...To keep open network more efficacious and secure, it is necessary that a nice trust model and method of trust management must be developed. The reason why traditional trust models are incomplete in their function to manage trust is explained, and a general model based on hybrid trust model and introducer protocol is provided. The hybrid model is more flexible and efficacious to manage trust compared with hierarchy model and Web model. The introducer protocol is a better solution to build, maintain and refresh the trust relationship in open network environment.展开更多
Three-party password-based key agreement protocols allow two users to authenticate each other via a public channel and establish a session key with the aid of a trusted server. Recently, Farash et al. [Farash M S, Att...Three-party password-based key agreement protocols allow two users to authenticate each other via a public channel and establish a session key with the aid of a trusted server. Recently, Farash et al. [Farash M S, Attari M A 2014 ＂An efficient and provably secure three-party password-based authenticated key exchange protocol based on Chebyshev chaotic maps＂, Nonlinear Dynamics 77（7）： 399-411] proposed a three-party key agreement protocol by using the extended chaotic maps. They claimed that their protocol could achieve strong security. In the present paper, we analyze Farash et al.＇s protocol and point out that this protocol is vulnerable to off-line password guessing attack and suffers communication burden. To handle the issue, we propose an efficient three-party password-based key agreement protocol using extended chaotic maps, which uses neither symmetric cryptosystems nor the server＇s public key. Compared with the relevant schemes, our protocol provides better performance in terms of computation and communication. Therefore, it is suitable for practical applications.展开更多
This paper proposed beta trust model based on energy load balancing combines the recent achievements of the trust models in distributed networks, together with the characteristics of wireless sensor networks. The inte...This paper proposed beta trust model based on energy load balancing combines the recent achievements of the trust models in distributed networks, together with the characteristics of wireless sensor networks. The inter-node trust relation is established after an overall evaluation of node trust value based on the monitor results of the node packets forwarding behavior conducted by inter-node collaboration. Due to the node energy limitation in wireless sensor networks, energy load balancing mechanism is applied to prolong the node survival time. And the redundant routing protocol involves the presented trust model to develop the novel trust routing protocol of beta trust model based on energy load balancing. Simulation performance demonstrates that the beta trust model based on energy load balancing outperforms current schemes in energy consumption.展开更多
针对区块链边缘节点的部署环境开放、安全措施薄弱、易受到安全攻击,以及计算和网络资源不足等问题,提出一种基于可信执行环境(TEE)的区块链安全架构P-Dledger。该架构通过构建两阶段的信任链,在满足软件便捷迭代的基础上,确保加载部件...针对区块链边缘节点的部署环境开放、安全措施薄弱、易受到安全攻击,以及计算和网络资源不足等问题,提出一种基于可信执行环境(TEE)的区块链安全架构P-Dledger。该架构通过构建两阶段的信任链,在满足软件便捷迭代的基础上,确保加载部件的可信;通过实现智能合约可信执行框架以及基于串行外设接口或非门存储器(SPI NOR Flash)的数据可信存储,保证智能合约的可信计算与数据的可信存储;同时,为共识提案赋予单调递增的唯一标识,限制拜占庭节点的行为。实验与分析结果表明:所提架构确保了加载主体、账本数据与执行过程的安全可信;当网络延时大于60 ms或节点数大于8时,P-Dledger比采用拜占庭容错(PBFT)算法的区块链系统的吞吐量更高,且随着网络延时与节点数的增加,P-Dledger性能表现更稳定。展开更多
城市复杂的建筑环境限制了车辆移动和无线信号自由传播,无线自组网呈现通信链路不稳定和拓扑间歇性连通等特点,传统的无线自组网路由方式无法很好地满足车载自组网(Vehicular Ad Hoc Networks,VANETs)的通信需求,VANETs的虚拟注册为Sybi...城市复杂的建筑环境限制了车辆移动和无线信号自由传播,无线自组网呈现通信链路不稳定和拓扑间歇性连通等特点,传统的无线自组网路由方式无法很好地满足车载自组网(Vehicular Ad Hoc Networks,VANETs)的通信需求,VANETs的虚拟注册为Sybil攻击提供了可能,路由路径不再可靠。针对这些问题,提出一种基于通信链路感知的可信路由协议,对通信链路状态进行量化评估,对节点行为进行信任建模,以链路质量和节点信任值作为新的路由决策依据,缓解因路由空洞、恶意评价等现象造成的影响。仿真结果表明,该方法在少量增加通信开销的情况下,能有效提升分组投递率,降低分组传输时延。展开更多
P2P文件共享网络的信任评价机制正面临着各种恶意攻击,例如聚集反馈、合谋欺骗和虚假交易,严重影响了整个系统的性能.为了保护P2P文件共享网络,提出了一种高精度自适应声誉机制,简称AARep机制(accurate and adaptive reputation mechani...P2P文件共享网络的信任评价机制正面临着各种恶意攻击,例如聚集反馈、合谋欺骗和虚假交易,严重影响了整个系统的性能.为了保护P2P文件共享网络,提出了一种高精度自适应声誉机制,简称AARep机制(accurate and adaptive reputation mechanism).经过分析发现,在信任评价系统中,除了对交易的评价,相关的交易信息也起着重要的作用.其贡献在于:1)通过以下手段,增加了信任值计算的精度:引入交易衰减函数,根据交易次序区分交易的重要程度;过滤掉具有低相似度的可疑节点;利用置信因子来反映观测值的可靠性;2)为了使置信因子起效,提出了一种简单的交易验证协议.实验结果表明,AARep能够显著消除或者减少各种攻击的威胁,提高系统性能.展开更多
基金supported by Nature Key Research and Development Program of China (2017YFB1400700)the National Natural Science Foundation of China (61602537, U1509214)+1 种基金the Central University of Finance and Economics Funds for the Youth Talent Support Plan (QYP1808)First-Class Discipline Construction in 2019,open fund of Key Laboratory of Grain Information Processing and Control (KFJJ-2018-202)
文摘Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.
文摘The security problems of wireless sensor networks (WSN) have attracted people’s wide attention. In this paper, after we have summarized the existing security problems and solutions in WSN, we find that the insider attack to WSN is hard to solve. Insider attack is different from outsider attack, because it can’t be solved by the traditional encryption and message authentication. Therefore, a reliable secure routing protocol should be proposed in order to defense the insider attack. In this paper, we focus on insider selective forwarding attack. The existing detection mechanisms, such as watchdog, multipath retreat, neighbor-based monitoring and so on, have both advantages and disadvantages. According to their characteristics, we proposed a secure routing protocol based on monitor node and trust mechanism. The reputation value is made up with packet forwarding rate and node’s residual energy. So this detection and routing mechanism is universal because it can take account of both the safety and lifetime of network. Finally, we use OPNET simulation to verify the performance of our algorithm.
文摘To keep open network more efficacious and secure, it is necessary that a nice trust model and method of trust management must be developed. The reason why traditional trust models are incomplete in their function to manage trust is explained, and a general model based on hybrid trust model and introducer protocol is provided. The hybrid model is more flexible and efficacious to manage trust compared with hierarchy model and Web model. The introducer protocol is a better solution to build, maintain and refresh the trust relationship in open network environment.
基金Project supported by the National Natural Science Foundation of China(Grant No.61462033)
文摘Three-party password-based key agreement protocols allow two users to authenticate each other via a public channel and establish a session key with the aid of a trusted server. Recently, Farash et al. [Farash M S, Attari M A 2014 ＂An efficient and provably secure three-party password-based authenticated key exchange protocol based on Chebyshev chaotic maps＂, Nonlinear Dynamics 77（7）： 399-411] proposed a three-party key agreement protocol by using the extended chaotic maps. They claimed that their protocol could achieve strong security. In the present paper, we analyze Farash et al.＇s protocol and point out that this protocol is vulnerable to off-line password guessing attack and suffers communication burden. To handle the issue, we propose an efficient three-party password-based key agreement protocol using extended chaotic maps, which uses neither symmetric cryptosystems nor the server＇s public key. Compared with the relevant schemes, our protocol provides better performance in terms of computation and communication. Therefore, it is suitable for practical applications.
文摘This paper proposed beta trust model based on energy load balancing combines the recent achievements of the trust models in distributed networks, together with the characteristics of wireless sensor networks. The inter-node trust relation is established after an overall evaluation of node trust value based on the monitor results of the node packets forwarding behavior conducted by inter-node collaboration. Due to the node energy limitation in wireless sensor networks, energy load balancing mechanism is applied to prolong the node survival time. And the redundant routing protocol involves the presented trust model to develop the novel trust routing protocol of beta trust model based on energy load balancing. Simulation performance demonstrates that the beta trust model based on energy load balancing outperforms current schemes in energy consumption.
文摘针对区块链边缘节点的部署环境开放、安全措施薄弱、易受到安全攻击,以及计算和网络资源不足等问题,提出一种基于可信执行环境(TEE)的区块链安全架构P-Dledger。该架构通过构建两阶段的信任链,在满足软件便捷迭代的基础上,确保加载部件的可信;通过实现智能合约可信执行框架以及基于串行外设接口或非门存储器(SPI NOR Flash)的数据可信存储,保证智能合约的可信计算与数据的可信存储;同时,为共识提案赋予单调递增的唯一标识,限制拜占庭节点的行为。实验与分析结果表明:所提架构确保了加载主体、账本数据与执行过程的安全可信;当网络延时大于60 ms或节点数大于8时,P-Dledger比采用拜占庭容错(PBFT)算法的区块链系统的吞吐量更高,且随着网络延时与节点数的增加,P-Dledger性能表现更稳定。
文摘城市复杂的建筑环境限制了车辆移动和无线信号自由传播,无线自组网呈现通信链路不稳定和拓扑间歇性连通等特点,传统的无线自组网路由方式无法很好地满足车载自组网(Vehicular Ad Hoc Networks,VANETs)的通信需求,VANETs的虚拟注册为Sybil攻击提供了可能,路由路径不再可靠。针对这些问题,提出一种基于通信链路感知的可信路由协议,对通信链路状态进行量化评估,对节点行为进行信任建模,以链路质量和节点信任值作为新的路由决策依据,缓解因路由空洞、恶意评价等现象造成的影响。仿真结果表明,该方法在少量增加通信开销的情况下,能有效提升分组投递率,降低分组传输时延。
文摘P2P文件共享网络的信任评价机制正面临着各种恶意攻击,例如聚集反馈、合谋欺骗和虚假交易,严重影响了整个系统的性能.为了保护P2P文件共享网络,提出了一种高精度自适应声誉机制,简称AARep机制(accurate and adaptive reputation mechanism).经过分析发现,在信任评价系统中,除了对交易的评价,相关的交易信息也起着重要的作用.其贡献在于:1)通过以下手段,增加了信任值计算的精度:引入交易衰减函数,根据交易次序区分交易的重要程度;过滤掉具有低相似度的可疑节点;利用置信因子来反映观测值的可靠性;2)为了使置信因子起效,提出了一种简单的交易验证协议.实验结果表明,AARep能够显著消除或者减少各种攻击的威胁,提高系统性能.
