We propose a Cross-Chain Mapping Blockchain(CCMB)for scalable data management in massive Internet of Things(IoT)networks.Specifically,CCMB aims to improve the scalability of securely storing,tracing,and transmitting I...We propose a Cross-Chain Mapping Blockchain(CCMB)for scalable data management in massive Internet of Things(IoT)networks.Specifically,CCMB aims to improve the scalability of securely storing,tracing,and transmitting IoT behavior and reputation data based on our proposed cross-mapped Behavior Chain(BChain)and Reputation Chain(RChain).To improve off-chain IoT data storage scalability,we show that our lightweight CCMB architecture efficiently utilizes available fog-cloud resources.The scalability of on-chain IoT data tracing is enhanced using our Mapping Smart Contract(MSC)and cross-chain mapping design to perform rapid Reputation-to-Behavior(R2B)traceability queries between BChain and RChain blocks.To maximize off-chain to on-chain throughput,we optimize the CCMB block settings and producers based on a general Poisson Point Process(PPP)network model.The constrained optimization problem is formulated as a Markov Decision Process(MDP),and solved using a dual-network Deep Reinforcement Learning(DRL)algorithm.Simulation results validate CCMB’s scalability advantages in storage,traceability,and throughput.In specific massive IoT scenarios,CCMB can reduce the storage footprint by 50%and traceability query time by 90%,while improving system throughput by 55%compared to existing benchmarks.展开更多
To increase the interoperability and privacy of digital asset transactions in multiparty cross-chain scenarios,Chen et al.proposed a cross-chain protocol based on multi-signatures and adaptor signatures that does not ...To increase the interoperability and privacy of digital asset transactions in multiparty cross-chain scenarios,Chen et al.proposed a cross-chain protocol based on multi-signatures and adaptor signatures that does not rely on smart contracts but instead depends on underlying scripts and signatures.However,since the protocol was designed without considering concurrent execution scenarios,it may still be vulnerable to certain types of attacks,posing potential security risks in practical applications.Therefore,this paper first presents an ROS attack against Chen et al.’s scheme,in which ROS attack was originally proposed by Benhamouda et al.in 2022 against the Schnorr-type threshold and multi-signatures and our attack exploits the random numbers generated by users in the offline-tolerant mechanism.By using a system of equations construction method,it is possible to forge valid signatures for arbitrary messages.Subsequently,the existing Chen et al.’s scheme is improved by establishing a nonlinear dependency between the random number and the message,without introducing additional interaction rounds or random parameters.This improvement eliminates the solvability of the linear system of equations in the ROS attack,thereby defending against this type of attack.Furthermore,security definitions and proofs are provided,detailing the complete properties of the improved adaptor signature scheme.Therefore,the proposed scheme in this paper enhances the theoretical security strength while maintaining the functionality and efficiency of Chen et al.’s scheme,and hence has more effective practicality.展开更多
Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection sche...Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection scheme based on Fully Homomorphic Encryption(FHE)is proposed.In the proposed scheme,the functional relationship is established by Box-Muller,Discrete Gaussian Distribution Function(DGDF)and Uniform Random Distribution Func-tion(URDF)are used to improve the security and efficiency of key generation.Subsequently,the data preprocessing function is introduced to perform cleaning,deduplication,and normalization operations on the transaction data of multi-key signature,and it is classified into interactive data and asset data,so as to perform different homomorphic operations in the FHE encryption stage.Ultimately,in the FHE encryption stage,homomorphic multiplication and homomorphic addition are used targeted for the interactive data and asset data,thereby reducing the computational complexity and enhancing the FHE encryption efficiency.The significance of the proposed scheme is proved by experimental results:Firstly,the multi-key generation function and its specific sampling method and transformation ensure the security and efficiency of key generation.Data preprocessing can also accelerate the FHE encryption process by eliminating invalid data and redundancy,so the FHE encryption efficiency is significantly improved.Secondly,the FHE encryption method based on discrete logarithm problem enhances the security of transaction data and can effectively resist multiple attacks.In addition,the preprocessed data also has good performance in capacity storage.The proposed scheme has significant impacts on key indicators such as encryption efficiency and security,it provides a new reference for blockchain cross-chain transaction protection technology and has an important impact on the security improvement of various cross-chain transaction data.展开更多
As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between...As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between different independent blockchain systems is restricting the expansion of blockchain. In this paper, a notary group-based cross-chain interaction model is proposed to achieve the interoperability between different blockchains. Firstly, a notary election mechanism is proposed to choose one notary from the notary group to act as a bridge for cross-chain transactions. Secondly, a margin pool is introduced to limit the misconduct of the elected notary and ensure the value transfer between the involved blockchains. Moreover, a reputation based incentive mechanism is used to encourage members of the notary group to participate in cross-chain transactions. Ethereum-based experiments demonstrate that the proposed mechanism can provide an acceptable performance for cross-chain transactions and provide a higher security level than ordinary cross-chain mechanisms.展开更多
The blockchain cross-chain is a significant technology for inter-chain interconnection and value transfer among different blockchain networks.Cross-chain overcomes the“information island”problem of the closed blockc...The blockchain cross-chain is a significant technology for inter-chain interconnection and value transfer among different blockchain networks.Cross-chain overcomes the“information island”problem of the closed blockchain network and is increasingly applied to multiple critical areas such as finance and the internet of things(IoT).Blockchain can be divided into three main categories of blockchain networks:public blockchains,private blockchains,and consortium blockchains.However,there are differences in block structures,consensus mechanisms,and complex working mechanisms among heterogeneous blockchains.The fragility of the cross-chain system itself makes the cross-chain system face some potential security and privacy threats.This paper discusses security defects on the cross-chain implementation mechanism,and discusses the impact of the structural features of blockchain networks on cross-chain security.In terms of cross-chain intercommunication,a cross-chain attack can be divided into a multi-chain combination attack,native chain attack,and inter-chain attack diffusion.Then various security threats and attack paths faced by the cross-chain system are analyzed.At last,the corresponding security defense methods of cross-chain security threats and future research directions for cross-chain applications are put forward.展开更多
With the development of the energy Internet, more distributed generators are connected to the power grid, resulting in numerous heterogeneous energy networks. However, different energy networks cannot perform efficien...With the development of the energy Internet, more distributed generators are connected to the power grid, resulting in numerous heterogeneous energy networks. However, different energy networks cannot perform efficient energy trading in the centralized management mode, this deeply affecting the complementary ability of heterogeneous energy, resulting in the islanded energy phenomenon. In this model, the same energy on the chain is traded within the chain, and the heterogeneous energy on different chains is traded across chains. To trade energy between heterogeneous energy networks more efficiently, the blockchain-based cross-chain model is proposed based on the existing infrastructure. Heterogeneous energy nodes are assigned to different energy sub-chains and cross-chain energy transactions are performed through a relay-chain, which utilizes the improved Boneh–Lynn–Shacham signature scheme consensus algorithm based on the proof-of-stake and practical Byzantine fault tolerance. The experimental simulations on energy trading efficiency, throughput, and security, show its superiority over existing systems. Further, the simulation results provide a reference for the application of cross-chain technology in energy interconnection.展开更多
JointCloud computing is a new computing paradigm that supports cloud services to achieve mutually beneficial outcomes.A key component of this model is the JointCloud computing distributed ledger,which ensures trust am...JointCloud computing is a new computing paradigm that supports cloud services to achieve mutually beneficial outcomes.A key component of this model is the JointCloud computing distributed ledger,which ensures trust among cloud entities with diverse interests by providing digital space evidence.Blockchain forms the foundation of this framework,and its adoption is growing in various fields to optimize workflows.However,challenges related to blockchain interoperability and cross-chain data authentication remain unresolved,hindering the broader establishment of trust among cloud entities.This paper focuses on the specific scenario of cross-chain data authentication and provides a secure and easy-to-deploy solution.Drawing on the concepts of relay chain and notary mechanism in cross-chain methods,our solution leverages smart contracts and on-chain proofs to ensure security,thereby reducing the reliance on relay nodes.In cases of data falsification,our method offers mechanisms for accountability and data revocation,further enhancing security.Additionally,participating blockchains do not need to alter their data structures or network compositions for authentication,which makes the solution easy to deploy.Experimental results demonstrate that our design can be easily deployed on both homogeneous and heterogeneous blockchains.While maintaining performance comparable to existing solutions,it significantly enhances system security.In the event of data falsification,the solution can quickly hold individuals accountable and eliminate the impact of falsified data,reducing the time to mitigate the impact by half compared with other solutions.展开更多
To solve the privacy leakage and identity island problems in cross-chain interaction,we propose an anti-quantum cross-chain identity authentication approach based on dynamic group signature(DGS-AQCCIDAA)for smart educ...To solve the privacy leakage and identity island problems in cross-chain interaction,we propose an anti-quantum cross-chain identity authentication approach based on dynamic group signature(DGS-AQCCIDAA)for smart education.The relay-based cross-chain model promotes interconnection in heterogeneous consortium blockchains.DGS is used as the endorsement strategy for cross-chain identity authentication.Our approach can ensure quantum security under the learning with error(LWE)and inhomogeneous small integer solution(ISIS)assumptions,and it uses non-interactive zero-knowledge proof(NIZKP)to protect user identity privacy.Our scheme has low calculation overhead and provides anonymous cross-chain identity authentication in the smart education system.展开更多
跨链是一种打破区块链网络“信息孤岛”,实现不同区块链网络之间互操作的重要技术。作为跨链实现的产物,跨链桥已成为异构区块链之间实现资产转移和信息传递的重要解决方案。近几年,针对跨链桥漏洞的攻击频繁发生,攻击导致的跨链交易异...跨链是一种打破区块链网络“信息孤岛”,实现不同区块链网络之间互操作的重要技术。作为跨链实现的产物,跨链桥已成为异构区块链之间实现资产转移和信息传递的重要解决方案。近几年,针对跨链桥漏洞的攻击频繁发生,攻击导致的跨链交易异常已造成高达数十亿的经济损失。然而,目前对跨链桥的异常交易问题研究较少,且仅有的一些检测工作高度依赖于人工总结的交易序列异常模式。针对这一问题,提出一种基于BERT(Bidirectional Encoder Representations from Transformers)模型的跨链异常交易检测方法,通过提供基于特征提取的2种检测模式,克服现有检测方法对人工经验依赖的局限性。第1种模式旨在更精准地提取特征,先根据交易状态从跨链原生交易数据中自动抽取具有关键特征的跨链交易序列,再通过跨链交易序列文本数据微调BERT-Base-Uncased预训练模型适应异常交易检测任务;第2种模式旨在弥补仅考虑关键跨链交易序列可能带来的特征不足,直接通过具有全面特征的原始交易文本数据微调BERT-Base-Uncased预训练模型进而解决异常交易检测任务。实验使用现有工作的真实跨链数据评估所提检测方法,结果表明,2种检测模式均能有效检测出异常的跨链交易,精确率、召回率及F1值均达到了100%。展开更多
At present, there is an urgent need for blockchain interoperability technology to realize interconnection between various blockchains, data communication and value transfer between blockchains, so as to break the ‘va...At present, there is an urgent need for blockchain interoperability technology to realize interconnection between various blockchains, data communication and value transfer between blockchains, so as to break the ‘value silo’ phenomenon of each blockchain. Firstly, it lists what people understand about the concept of interoperability. Secondly, it gives the key technical issues of cross-chain, including cross-chain mechanism, interoperability, eventual consistency, and universality. Then, the implementation of each cross-chain key technology is analyzed, including Hash-locking, two-way peg, notary schemes, relay chain scheme, cross-chain protocol, and global identity system. Immediately after that, five typical cross-chain systems are introduced and comparative analysis is made. In addition, two examples of cross-chain programmability and their analysis are given. Finally, the current state of cross-chain technology is summarized from two aspects: key technology implementation and cross-chain application enforcement. The cross-chain technology as a whole has formed a centralized fixed mechanism, as well as a trend of modular design, and some of the solutions to mature applications were established in the relevant standards organizations, and the cross-chain technology architecture tends to be unified, which is expected to accelerate the evolution of the open cross-chain network that supports the real needs of the interconnection of all chains.展开更多
To solve the current situation of low vehicle-to-pile ratio,charging pile(CP)operators incorporate private CPs into the shared charging system.However,the introduction of private CP has brought about the problem of po...To solve the current situation of low vehicle-to-pile ratio,charging pile(CP)operators incorporate private CPs into the shared charging system.However,the introduction of private CP has brought about the problem of poor service quality.Reputation is a common service evaluation scheme,in which the third-party reputation scheme has the issue of single point of failure;although the blockchain-based reputation scheme solves the single point of failure issue,it also brings the challenges of storage and query efficiency.It is a feasible solution to classify and store information on multiple chains,and at this time,reputation needs to be calculated in a cross-chain mode.Crosschain reputation calculation faces the problems of correctness verification,integrity verification and efficiency.Therefore,this paper proposes a verifiable and efficient cross-chain calculation model for CP reputation.Specially,in this model,we propose a verifiable cross-chain contract calculation scheme that adopts polynomial commitment to solve the problems of polynomial damage and tampering that may be encountered in the crosschain process of outsourced polynomials,so as to ensure the integrity and correctness of polynomial calculations.In addition,the miner selection and incentive mechanism algorithm in this scheme ensures the correctness of extracted information when the outsourced polynomial is calculated on the blockchain.The security analysis and experimental results demonstrate that this scheme is feasible in practice.展开更多
The communication efficiency optimization,censorship resilience,and generation of shared randomness are inseparable from the threshold cryptography in the existing Byzantine Fault Tolerant(BFT)consensus.The membership...The communication efficiency optimization,censorship resilience,and generation of shared randomness are inseparable from the threshold cryptography in the existing Byzantine Fault Tolerant(BFT)consensus.The membership in consensus in a blockchain scenario supports dynamic changes,which effectively prevents the corruption of consensus participants.Especially in cross-chain protocols,the dynamic access to different blockchains will inevitably bring about the demand for member dynamic.Most existing threshold cryptography schemes rely on redefined key shares,leading to a static set of secret sharing participants.In this paper,we propose a general approach to coupling blockchain consensus and dynamic secret sharing.The committee performs consensus confirmation of both dynamic secret sharing and transaction proposals.Our scheme facilitates threshold cryptography membership dynamic,thus underlying support for membership dynamic of threshold cryptographybased BFT consensus schemes.We instantiate a dynamic HotStuff consensus to demonstrate the effectiveness of the scheme.After the correctness and security proof,our scheme achieves the secrecy and integrity of the threshold key shares while ensuring consensus liveness and safety.Experimental results prove that our scheme obtains dynamic membership with negligible overhead.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant 2023YFB3106900the National Natural Science Foundation of China under Grant 62171113the China Scholarship Council under Grant 202406080100.
文摘We propose a Cross-Chain Mapping Blockchain(CCMB)for scalable data management in massive Internet of Things(IoT)networks.Specifically,CCMB aims to improve the scalability of securely storing,tracing,and transmitting IoT behavior and reputation data based on our proposed cross-mapped Behavior Chain(BChain)and Reputation Chain(RChain).To improve off-chain IoT data storage scalability,we show that our lightweight CCMB architecture efficiently utilizes available fog-cloud resources.The scalability of on-chain IoT data tracing is enhanced using our Mapping Smart Contract(MSC)and cross-chain mapping design to perform rapid Reputation-to-Behavior(R2B)traceability queries between BChain and RChain blocks.To maximize off-chain to on-chain throughput,we optimize the CCMB block settings and producers based on a general Poisson Point Process(PPP)network model.The constrained optimization problem is formulated as a Markov Decision Process(MDP),and solved using a dual-network Deep Reinforcement Learning(DRL)algorithm.Simulation results validate CCMB’s scalability advantages in storage,traceability,and throughput.In specific massive IoT scenarios,CCMB can reduce the storage footprint by 50%and traceability query time by 90%,while improving system throughput by 55%compared to existing benchmarks.
基金supported by the National Natural Science Foundation of China(61907042,61702570)the Beijing Natural Science Foundation(4194090)+1 种基金the Social Science Planning Project of Shandong Province(24CWYJ05)the Project of Research on the Course System of“Blockchain Technology and Applications”Based on the TuGraph Platform,Ant Group Co.,Ltd.
文摘To increase the interoperability and privacy of digital asset transactions in multiparty cross-chain scenarios,Chen et al.proposed a cross-chain protocol based on multi-signatures and adaptor signatures that does not rely on smart contracts but instead depends on underlying scripts and signatures.However,since the protocol was designed without considering concurrent execution scenarios,it may still be vulnerable to certain types of attacks,posing potential security risks in practical applications.Therefore,this paper first presents an ROS attack against Chen et al.’s scheme,in which ROS attack was originally proposed by Benhamouda et al.in 2022 against the Schnorr-type threshold and multi-signatures and our attack exploits the random numbers generated by users in the offline-tolerant mechanism.By using a system of equations construction method,it is possible to forge valid signatures for arbitrary messages.Subsequently,the existing Chen et al.’s scheme is improved by establishing a nonlinear dependency between the random number and the message,without introducing additional interaction rounds or random parameters.This improvement eliminates the solvability of the linear system of equations in the ROS attack,thereby defending against this type of attack.Furthermore,security definitions and proofs are provided,detailing the complete properties of the improved adaptor signature scheme.Therefore,the proposed scheme in this paper enhances the theoretical security strength while maintaining the functionality and efficiency of Chen et al.’s scheme,and hence has more effective practicality.
文摘Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection scheme based on Fully Homomorphic Encryption(FHE)is proposed.In the proposed scheme,the functional relationship is established by Box-Muller,Discrete Gaussian Distribution Function(DGDF)and Uniform Random Distribution Func-tion(URDF)are used to improve the security and efficiency of key generation.Subsequently,the data preprocessing function is introduced to perform cleaning,deduplication,and normalization operations on the transaction data of multi-key signature,and it is classified into interactive data and asset data,so as to perform different homomorphic operations in the FHE encryption stage.Ultimately,in the FHE encryption stage,homomorphic multiplication and homomorphic addition are used targeted for the interactive data and asset data,thereby reducing the computational complexity and enhancing the FHE encryption efficiency.The significance of the proposed scheme is proved by experimental results:Firstly,the multi-key generation function and its specific sampling method and transformation ensure the security and efficiency of key generation.Data preprocessing can also accelerate the FHE encryption process by eliminating invalid data and redundancy,so the FHE encryption efficiency is significantly improved.Secondly,the FHE encryption method based on discrete logarithm problem enhances the security of transaction data and can effectively resist multiple attacks.In addition,the preprocessed data also has good performance in capacity storage.The proposed scheme has significant impacts on key indicators such as encryption efficiency and security,it provides a new reference for blockchain cross-chain transaction protection technology and has an important impact on the security improvement of various cross-chain transaction data.
基金supported by the National Natural Science Foundation of China (Nos. 61903056 and 61702066)the Chongqing Research Program of Basic Research and Frontier Technology (No. cstc2019jcyj-msxmX0681).
文摘As an emerging distributed technology, blockchain has begun to penetrate into many fields such as finance, healthcare, supply chain, intelligent transportation. However, the interoperability and value exchange between different independent blockchain systems is restricting the expansion of blockchain. In this paper, a notary group-based cross-chain interaction model is proposed to achieve the interoperability between different blockchains. Firstly, a notary election mechanism is proposed to choose one notary from the notary group to act as a bridge for cross-chain transactions. Secondly, a margin pool is introduced to limit the misconduct of the elected notary and ensure the value transfer between the involved blockchains. Moreover, a reputation based incentive mechanism is used to encourage members of the notary group to participate in cross-chain transactions. Ethereum-based experiments demonstrate that the proposed mechanism can provide an acceptable performance for cross-chain transactions and provide a higher security level than ordinary cross-chain mechanisms.
基金supported by the Beijing Natural Science Foundation(4212008)the National Natural Science Foundation of China(62272031)+2 种基金the Open Foundation of Information Security Evaluation Center of Civil Aviation,Civil Aviation University of China(ISECCA-202101)Guangxi Key Laboratory of Cryptography and Information Security(GCIS201915)supported in part by the National Natural Science Foundation of China(U21A20463,U22B2027)。
文摘The blockchain cross-chain is a significant technology for inter-chain interconnection and value transfer among different blockchain networks.Cross-chain overcomes the“information island”problem of the closed blockchain network and is increasingly applied to multiple critical areas such as finance and the internet of things(IoT).Blockchain can be divided into three main categories of blockchain networks:public blockchains,private blockchains,and consortium blockchains.However,there are differences in block structures,consensus mechanisms,and complex working mechanisms among heterogeneous blockchains.The fragility of the cross-chain system itself makes the cross-chain system face some potential security and privacy threats.This paper discusses security defects on the cross-chain implementation mechanism,and discusses the impact of the structural features of blockchain networks on cross-chain security.In terms of cross-chain intercommunication,a cross-chain attack can be divided into a multi-chain combination attack,native chain attack,and inter-chain attack diffusion.Then various security threats and attack paths faced by the cross-chain system are analyzed.At last,the corresponding security defense methods of cross-chain security threats and future research directions for cross-chain applications are put forward.
基金supported by the Fundamental Research Funds for the Central Universities of Ministry of Education (2018 ZD06)。
文摘With the development of the energy Internet, more distributed generators are connected to the power grid, resulting in numerous heterogeneous energy networks. However, different energy networks cannot perform efficient energy trading in the centralized management mode, this deeply affecting the complementary ability of heterogeneous energy, resulting in the islanded energy phenomenon. In this model, the same energy on the chain is traded within the chain, and the heterogeneous energy on different chains is traded across chains. To trade energy between heterogeneous energy networks more efficiently, the blockchain-based cross-chain model is proposed based on the existing infrastructure. Heterogeneous energy nodes are assigned to different energy sub-chains and cross-chain energy transactions are performed through a relay-chain, which utilizes the improved Boneh–Lynn–Shacham signature scheme consensus algorithm based on the proof-of-stake and practical Byzantine fault tolerance. The experimental simulations on energy trading efficiency, throughput, and security, show its superiority over existing systems. Further, the simulation results provide a reference for the application of cross-chain technology in energy interconnection.
基金supported by the National Key Research and Development Program of China under Grant No.2022ZD0115302in part by the National Natural Science Foundation of China under Grant Nos.62202479 and 61772030+1 种基金the Major Program of Xiangjiang Laboratory under Grant No.22XJ01004the Major Project of Technology Innovation of Hunan Province of China under Grant No.2021SK1060-1.
文摘JointCloud computing is a new computing paradigm that supports cloud services to achieve mutually beneficial outcomes.A key component of this model is the JointCloud computing distributed ledger,which ensures trust among cloud entities with diverse interests by providing digital space evidence.Blockchain forms the foundation of this framework,and its adoption is growing in various fields to optimize workflows.However,challenges related to blockchain interoperability and cross-chain data authentication remain unresolved,hindering the broader establishment of trust among cloud entities.This paper focuses on the specific scenario of cross-chain data authentication and provides a secure and easy-to-deploy solution.Drawing on the concepts of relay chain and notary mechanism in cross-chain methods,our solution leverages smart contracts and on-chain proofs to ensure security,thereby reducing the reliance on relay nodes.In cases of data falsification,our method offers mechanisms for accountability and data revocation,further enhancing security.Additionally,participating blockchains do not need to alter their data structures or network compositions for authentication,which makes the solution easy to deploy.Experimental results demonstrate that our design can be easily deployed on both homogeneous and heterogeneous blockchains.While maintaining performance comparable to existing solutions,it significantly enhances system security.In the event of data falsification,the solution can quickly hold individuals accountable and eliminate the impact of falsified data,reducing the time to mitigate the impact by half compared with other solutions.
基金Project supported by the Horizontal Project(No.HX2024-002)the Open Foundation of Key Laboratory of Cyberspace Security of the Ministry of Education of China(No.KLCS20240102)the Natural Science Basis Research Program of Shaanxi Province(Nos.2025JC-YBMS-652 and 2025JC-YBMS-676)。
文摘To solve the privacy leakage and identity island problems in cross-chain interaction,we propose an anti-quantum cross-chain identity authentication approach based on dynamic group signature(DGS-AQCCIDAA)for smart education.The relay-based cross-chain model promotes interconnection in heterogeneous consortium blockchains.DGS is used as the endorsement strategy for cross-chain identity authentication.Our approach can ensure quantum security under the learning with error(LWE)and inhomogeneous small integer solution(ISIS)assumptions,and it uses non-interactive zero-knowledge proof(NIZKP)to protect user identity privacy.Our scheme has low calculation overhead and provides anonymous cross-chain identity authentication in the smart education system.
文摘跨链是一种打破区块链网络“信息孤岛”,实现不同区块链网络之间互操作的重要技术。作为跨链实现的产物,跨链桥已成为异构区块链之间实现资产转移和信息传递的重要解决方案。近几年,针对跨链桥漏洞的攻击频繁发生,攻击导致的跨链交易异常已造成高达数十亿的经济损失。然而,目前对跨链桥的异常交易问题研究较少,且仅有的一些检测工作高度依赖于人工总结的交易序列异常模式。针对这一问题,提出一种基于BERT(Bidirectional Encoder Representations from Transformers)模型的跨链异常交易检测方法,通过提供基于特征提取的2种检测模式,克服现有检测方法对人工经验依赖的局限性。第1种模式旨在更精准地提取特征,先根据交易状态从跨链原生交易数据中自动抽取具有关键特征的跨链交易序列,再通过跨链交易序列文本数据微调BERT-Base-Uncased预训练模型适应异常交易检测任务;第2种模式旨在弥补仅考虑关键跨链交易序列可能带来的特征不足,直接通过具有全面特征的原始交易文本数据微调BERT-Base-Uncased预训练模型进而解决异常交易检测任务。实验使用现有工作的真实跨链数据评估所提检测方法,结果表明,2种检测模式均能有效检测出异常的跨链交易,精确率、召回率及F1值均达到了100%。
文摘目前,多无人机(Unmanned Aerial Vehicle,UAV)在大规模任务场景下的任务分配问题仍是一个挑战性问题。传统启发式算法可在较低计算复杂度下得到满意的解,但收敛速度慢且难以收敛到全局最优解。为此提出一种基于UAV链、任务链和双阶段修复策略的遗传算法(Genetic Algorithm Based on UAV-chain,Task-chain,and Two-Stage Repair strategy,UTTSRGA)。在编码结构中设计UAV链和任务链来量化任务执行代价,增强了编码中的信息承载能力并显著提升搜索效率。针对交叉操作后出现任务缺失与任务重复问题,设计双阶段修复策略。第一阶段设计随机填充机制,增强对解空间的全局搜索能力;第二阶段设计邻接映射表修复机制,根据任务间的邻接关系提供进化方向,有效引导种群向当前最优解快速收敛。提出动态复合变异策略,融合自适应变异率与基于任务链值的变异点选择,并设计4种功能互补的变异算子,多维度协同优化解的质量。针对大规模场景下的路径交叉问题,引入路径优化策略,从实践角度进一步优化任务分配方案。实验结果表明,UTTSRGA在不同任务规模下,尤其是大规模复杂任务场景中,在解的质量、收敛速度和鲁棒性3个方面均表现出显著优势。
文摘At present, there is an urgent need for blockchain interoperability technology to realize interconnection between various blockchains, data communication and value transfer between blockchains, so as to break the ‘value silo’ phenomenon of each blockchain. Firstly, it lists what people understand about the concept of interoperability. Secondly, it gives the key technical issues of cross-chain, including cross-chain mechanism, interoperability, eventual consistency, and universality. Then, the implementation of each cross-chain key technology is analyzed, including Hash-locking, two-way peg, notary schemes, relay chain scheme, cross-chain protocol, and global identity system. Immediately after that, five typical cross-chain systems are introduced and comparative analysis is made. In addition, two examples of cross-chain programmability and their analysis are given. Finally, the current state of cross-chain technology is summarized from two aspects: key technology implementation and cross-chain application enforcement. The cross-chain technology as a whole has formed a centralized fixed mechanism, as well as a trend of modular design, and some of the solutions to mature applications were established in the relevant standards organizations, and the cross-chain technology architecture tends to be unified, which is expected to accelerate the evolution of the open cross-chain network that supports the real needs of the interconnection of all chains.
基金supported in part by Beijing Natural Science Foundation(M21029)the National Natural Science Foundation of China(62272007)。
文摘To solve the current situation of low vehicle-to-pile ratio,charging pile(CP)operators incorporate private CPs into the shared charging system.However,the introduction of private CP has brought about the problem of poor service quality.Reputation is a common service evaluation scheme,in which the third-party reputation scheme has the issue of single point of failure;although the blockchain-based reputation scheme solves the single point of failure issue,it also brings the challenges of storage and query efficiency.It is a feasible solution to classify and store information on multiple chains,and at this time,reputation needs to be calculated in a cross-chain mode.Crosschain reputation calculation faces the problems of correctness verification,integrity verification and efficiency.Therefore,this paper proposes a verifiable and efficient cross-chain calculation model for CP reputation.Specially,in this model,we propose a verifiable cross-chain contract calculation scheme that adopts polynomial commitment to solve the problems of polynomial damage and tampering that may be encountered in the crosschain process of outsourced polynomials,so as to ensure the integrity and correctness of polynomial calculations.In addition,the miner selection and incentive mechanism algorithm in this scheme ensures the correctness of extracted information when the outsourced polynomial is calculated on the blockchain.The security analysis and experimental results demonstrate that this scheme is feasible in practice.
基金supported by the National Key R&D Program of China(2020YFB1005600)the Beijing Natural Science Foundation(M21031)+3 种基金the Natural Science Foundation of China through projects(U21A20467,61932011,62002011,61972019)the Populus euphratica found(CCF-HuaweiBC2021009)the Open Research Fund of Key Laboratory of Cryptography of Zhejiang Province(ZCL21007)the Youth Top Talent Support Program of Beihang University(YWF-22-L-1272).
文摘The communication efficiency optimization,censorship resilience,and generation of shared randomness are inseparable from the threshold cryptography in the existing Byzantine Fault Tolerant(BFT)consensus.The membership in consensus in a blockchain scenario supports dynamic changes,which effectively prevents the corruption of consensus participants.Especially in cross-chain protocols,the dynamic access to different blockchains will inevitably bring about the demand for member dynamic.Most existing threshold cryptography schemes rely on redefined key shares,leading to a static set of secret sharing participants.In this paper,we propose a general approach to coupling blockchain consensus and dynamic secret sharing.The committee performs consensus confirmation of both dynamic secret sharing and transaction proposals.Our scheme facilitates threshold cryptography membership dynamic,thus underlying support for membership dynamic of threshold cryptographybased BFT consensus schemes.We instantiate a dynamic HotStuff consensus to demonstrate the effectiveness of the scheme.After the correctness and security proof,our scheme achieves the secrecy and integrity of the threshold key shares while ensuring consensus liveness and safety.Experimental results prove that our scheme obtains dynamic membership with negligible overhead.
