Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchai...Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchain is widely used in the field of access control with its decentralization,traceability and non-defective modification.Combining the blockchain technology and the Bell-LaPadula model,we propose a new access control model,named BCBLPM,for MLS environment.The“multi-chain”blockchain architecture is used for dividing resources into isolated access domains,providing a fine-grained data protection mechanism.The access control policies are implemented by smart contracts deployed in each access domain,so that the side chains of different access domains storage access records from outside and maintain the integrity of the records.Finally,we implement the BC-BLPM prototype system using the Hyperledger Fabric.The experimental and analytical results show that the model can adapt well to the needs of multi-level security environment,and it has the feasibility of application in actual scenarios.展开更多
Blockchain technology is increasingly popular and has been widely applied in many industrial fields,due to its unique properties of decentralization,immutability,and traceability.Blockchain systems in different fields...Blockchain technology is increasingly popular and has been widely applied in many industrial fields,due to its unique properties of decentralization,immutability,and traceability.Blockchain systems in different fields vary,with different block structures,consensus mechanisms and access permission models.These differences make it hard for different blockchain systems to interoperate with each other,which isolates them.Cross-chain technologies have been developed to solve this isolation problem in order to improve the interoperability of blockchains.Although some surveys on cross-chain technologies can be found,they are unable to keep up with the latest research progress due to their extremely fast pace of development.Moreover,the literature misses general criteria to evaluate the quality of cross-chain technologies.In this paper,a comprehensive literature review of cross-chain technologies is conducted by employing a comprehensive set of evaluation criteria.The preliminaries on blockchain interoperability are first presented.Then,a set of evaluation criteria is proposed in terms of security,privacy,performance,and functionality.The latest cutting-edge works are reviewed based on the proposed taxonomy of cross-chain technologies and their performance is evaluated against our proposed criteria.Finally,some open issues and future directions of cross-chain research are pointed out.展开更多
Network marketing is a trading technique that provides companies with the opportunity to increase sales.With the increasing number of Internet-based purchases,several threats are increasingly observed in this field,su...Network marketing is a trading technique that provides companies with the opportunity to increase sales.With the increasing number of Internet-based purchases,several threats are increasingly observed in this field,such as user privacy violations,company owner(CO)fraud,the changing of sold products’information,and the scalability of selling networks.This study presents the concept of a blockchain-based market called ACR-MLM that functions based on the multi-level marketing(MLM)model,through which registered users receive anonymous and confidential rewards for their own and their subgroups’sales.Applying a public blockchain as the ACR-MLM framework’s infrastructure solves existing problems in MLM-based markets,such as CO fraud(against the government or its users),user privacy violations(obtaining their real names or subgroup users),and scalability(when vast numbers of users have been registered).To provide confidentiality and scalability to the ACR-MLM framework,hierarchical identity-based encryption(HIBE)was applied with a functional encryption(FE)scheme.Finally,the security of ACR-MLM is analyzed using the random oracle(RO)model and then evaluated.展开更多
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple...The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections.展开更多
Taxation,the primary source of fiscal revenue,has profound implications in guiding resource allocation,promoting economic growth,adjusting social wealth distribution,and enhancing cultural influence.The development of...Taxation,the primary source of fiscal revenue,has profound implications in guiding resource allocation,promoting economic growth,adjusting social wealth distribution,and enhancing cultural influence.The development of e-taxation provides a enhanced security for taxation,but it still faces the risk of inefficiency and tax data leakage.As a decentralized ledger,blockchain provides an effective solution for protecting tax data and avoiding tax-related errors and fraud.The introduction of blockchain into e-taxation protocols can ensure the public verification of taxes.However,balancing taxpayer identity privacy with regulation remains a challenge.In this paper,we propose a blockchain-based anonymous and regulatory e-taxation protocol.This protocol ensures the supervision and tracking of malicious taxpayers while maintaining honest taxpayer identity privacy,reduces the storage needs for public key certificates in the public key infrastructure,and enables selfcertification of taxpayers’public keys and addresses.We formalize the security model of unforgeability for transactions,anonymity for honest taxpayers,and traceability for malicious taxpayers.Security analysis shows that the proposed protocol satisfies unforgeability,anonymity,and traceability.The experimental results of time consumption show that the protocol is feasible in practical applications.展开更多
Adaptor signature,a new primitive that alleviates the scalability issue of blockchain to some extent,has been widely adopted in the off-chain payment channel and atomic swap.As an extension of standard digital signatu...Adaptor signature,a new primitive that alleviates the scalability issue of blockchain to some extent,has been widely adopted in the off-chain payment channel and atomic swap.As an extension of standard digital signature,adaptor signature can bind the release of a complete digital signature with the exchange of a secret value.Existing constructions of adaptor signatures are mainly based on Schnorr or ECDSA signature algorithms,which suffer low signing efficiency and long signature length.In this paper,to address these issues,we propose a new construction of adaptor signature using randomized EdDSA,which has Schnorr-like structure with higher signing efficiency and shorter signature length.We prove the required security properties,including unforgeability,witness extractability and pre-signature adaptability,of the new adaptor signature scheme in the random oracle model.We conduct a comparative analysis with an ECDSA-based adaptor signature scheme to demonstrate the effectiveness and feasibility of our new proposal.展开更多
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge...As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes.展开更多
The Internet of Things(IoT)has gained substantial attention in both academic research and real-world applications.The proliferation of interconnected devices across various domains promises to deliver intelligent and ...The Internet of Things(IoT)has gained substantial attention in both academic research and real-world applications.The proliferation of interconnected devices across various domains promises to deliver intelligent and advanced services.However,this rapid expansion also heightens the vulnerability of the IoT ecosystem to security threats.Consequently,innovative solutions capable of effectively mitigating risks while accommodating the unique constraints of IoT environments are urgently needed.Recently,the convergence of Blockchain technology and IoT has introduced a decentralized and robust framework for securing data and interactions,commonly referred to as the Internet of Blockchained Things(IoBT).Extensive research efforts have been devoted to adapting Blockchain technology to meet the specific requirements of IoT deployments.Within this context,consensus algorithms play a critical role in assessing the feasibility of integrating Blockchain into IoT ecosystems.The adoption of efficient and lightweight consensus mechanisms for block validation has become increasingly essential.This paper presents a comprehensive examination of lightweight,constraint-aware consensus algorithms tailored for IoBT.The study categorizes these consensus mechanisms based on their core operations,the security of the block validation process,the incorporation of AI techniques,and the specific applications they are designed to support.展开更多
Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a...Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a bottleneck to the widespread adoption of UCAN in 6G.In this paper,we propose Overlap Shard,a blockchain framework based on a novel reputation voting(RV)scheme,to dynamically manage the APs in UCAN.AP nodes in UCAN are distributed across multiple shards based on the RV scheme.That is,nodes with good reputation(virtuous behavior)are likely to be selected in the overlap shard.The RV mechanism ensures the security of UCAN because most APs adopt virtuous behaviors.Furthermore,to improve the efficiency of the Overlap Shard,we reduce cross-shard transactions by introducing core nodes.Specifically,a few nodes are overlapped in different shards,which can directly process the transactions in two shards instead of crossshard transactions.This greatly increases the speed of transactions between shards and thus the throughput of the overlap shard.The experiments show that the throughput of the overlap shard is about 2.5 times that of the non-sharded blockchain.展开更多
The accelerated advancement of the Internet of Things(IoT)has generated substantial data,including sensitive and private information.Consequently,it is imperative to guarantee the security of data sharing.While facili...The accelerated advancement of the Internet of Things(IoT)has generated substantial data,including sensitive and private information.Consequently,it is imperative to guarantee the security of data sharing.While facilitating fine-grained access control,Ciphertext Policy Attribute-Based Encryption(CP-ABE)can effectively ensure the confidentiality of shared data.Nevertheless,the conventional centralized CP-ABE scheme is plagued by the issues of keymisuse,key escrow,and large computation,which will result in security risks.This paper suggests a lightweight IoT data security sharing scheme that integrates blockchain technology and CP-ABE to address the abovementioned issues.The integrity and traceability of shared data are guaranteed by the use of blockchain technology to store and verify access transactions.The encryption and decryption operations of the CP-ABE algorithm have been implemented using elliptic curve scalarmultiplication to accommodate lightweight IoT devices,as opposed to themore arithmetic bilinear pairing found in the traditional CP-ABE algorithm.Additionally,a portion of the computation is delegated to the edge nodes to alleviate the computational burden on users.A distributed key management method is proposed to address the issues of key escrow andmisuse.Thismethod employs the edge blockchain to facilitate the storage and distribution of attribute private keys.Meanwhile,data security sharing is enhanced by combining off-chain and on-chain ciphertext storage.The security and performance analysis indicates that the proposed scheme is more efficient and secure.展开更多
Within the framework of the 2030 Agenda and to achieve the Sustainable Development Goals(SDGs),science,technology and innovation play an even more central role.Building on this foundation,the primary objective of this...Within the framework of the 2030 Agenda and to achieve the Sustainable Development Goals(SDGs),science,technology and innovation play an even more central role.Building on this foundation,the primary objective of this paper is to explore the potential applications of blockchain in supporting the achievement of these sustainability goals.Starting from a review of the relevant literature on this topic,the main fields in which blockchain can contribute to sustainable development will be identified.The main blockchain applications will then be analyzed and categorized according to these SDGs.This research will then critically present the main blockchain-based projects that emerged in the first stage of the study and were implemented by the United Nations.The main objectives and benefits of each project will be analyzed.This is where the originality of this paper lies.To the best of the author’s knowledge,this is one of the first attempts to present a comprehensive overview of the United Nations’projects related to SDGs 1,2,5,7,9,13,and 16.This paper,which bridges the gap between innovation management and the sustainability field,will contribute to the increasingly current debate on sustainability issues and be beneficial to scholars,practitioners,and policymakers alike.展开更多
Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privac...Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privacy-preserving Web3 scenarios.However,DFL faces incentive and security challenges in the decentralized framework.To address these issues,this paper presents a Hierarchical Blockchain-enabled DFL(HBDFL)system,which provides a generic solution framework for the DFL-related applications.The proposed system consists of four major components,including a model contribution-based reward mechanism,a Proof of Elapsed Time and Accuracy(PoETA)consensus algorithm,a Distributed Reputation-based Verification Mechanism(DRTM)and an Accuracy-Dependent Throughput Management(ADTM)mechanism.The model contribution-based rewarding mechanism incentivizes network nodes to train models with their local datasets,while the PoETA consensus algorithm optimizes the tradeoff between the shared model accuracy and system throughput.The DRTM improves the system efficiency in consensus,and the ADTM mechanism guarantees that the throughput performance remains within a predefined range while improving the shared model accuracy.The performance of the proposed HBDFL system is evaluated by numerical simulations,with the results showing that the system improves the accuracy of the shared model while maintaining high throughput and ensuring security.展开更多
The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a block...The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a blockchain-enabled manufacturing collaboration framework is proposed,with a focus on the production capacity matching problem for blockchainbased peer-to-peer(P2P)collaboration.First,a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain.Second,an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants.Third,a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information.It facilitates automation of the matching process while protecting users'privacy via blockchainbased smart contracts.Finally,simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4%compared to the Bayesian game-based approach,makes all participants profitable,and achieves 90%fairness of enterprises.展开更多
This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain technology.By combining the strengths of blockchain an...This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain technology.By combining the strengths of blockchain and generative AI,the research team aimed to address the timely challenge of safeguarding visual medical content.The participating researchers conducted a comprehensive analysis,examining the vulnerabilities of medical AI services,personal information protection issues,and overall security weaknesses.This multi faceted exploration led to an indepth evaluation of the model’s performance and security.Notably,the correlation between accuracy,detection rate,and error rate was scrutinized.This analysis revealed insights into the model’s strengths and limitations,while the consideration of standard deviation shed light on the model’s stability and performance variability.The study proposed practical improvements,emphasizing the reduction of false negatives to enhance detection rate and leveraging blockchain technology to ensure visual data integrity in medical applications.Applying blockchain to generative AI-created medical content addresses key personal information protection issues.By utilizing the distributed ledger system of blockchain,the research team aimed to protect the privacy and integrity of medical data especially medical images.This approach not only enhances security but also enables transparent and tamperproof record-keeping.Additionally,the use of generative AI models ensures the creation of novel medical content without compromising personal information,further safeguarding patient privacy.In conclusion,this study showcases the potential of blockchain-based solutions in the medical field,particularly in securing sensitive medical data and protecting patient privacy.The proposed approach,combining blockchain and generative AI,offers a promising direction toward more robust and secure medical content management.Further research and advancements in this area will undoubtedly contribute to the development of robust and privacy-preserving healthcare systems,and visual diagnostic systems.展开更多
The rapid growth of blockchain and Decentralized Finance(DeFi)has introduced new challenges and vulnerabilities that threaten the integrity and efficiency of the ecosystem.This study identifies critical issues such as...The rapid growth of blockchain and Decentralized Finance(DeFi)has introduced new challenges and vulnerabilities that threaten the integrity and efficiency of the ecosystem.This study identifies critical issues such as Transaction Order Dependence(TOD),Blockchain Extractable Value(BEV),and Transaction Importance Diversity(TID),which collectively undermine the fairness and security of DeFi systems.BEV-related activities,including sandwich attacks,liquidations,transaction replay etc.have emerged as significant threats,collectively generating$540.54 million in losses over 32 months across 11,289 addresses,involving 49,691 cryptocurrencies and 60,830 on-chain markets.These attacks exploit transaction mechanics to manipulate asset prices and extract value at the expense of other participants,with sandwich attacks being particularly impactful.Additionally,the growing adoption of blockchain in traditional finance highlights the challenge of TID,wherein high transaction volumes can strain systems and compromise time-sensitive operations.To address these pressing issues,we propose a novel Distributed Transaction Sequencing Strategy(DTSS)that integrates forking mechanisms with an Analytic Hierarchy Process(AHP)to enforce fair and transparent transaction ordering in a decentralized manner.Our approach is further enhanced by an optimization framework and the introduction of a Normalized Allocation Disparity Metric(NADM)that ensures optimal parameter selection for transaction prioritization.Experimental evaluations demonstrated that the DTSS effectively mitigated BEV risks,enhanced transaction fairness,and significantly improved the security and transparency of DeFi ecosystems.展开更多
The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the explo...The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the exploration of diverse applications arising from this evolving quantum computing paradigm.The scope of the related research is notably diverse.This paper consolidates and presents quantum computing research related to the financial sector.The finance applications considered in this study include portfolio optimization,fraud detection,and Monte Carlo methods for derivative pricing and risk calculation.In addition,we provide a comprehensive analysis of quantum computing’s applications and effects on blockchain technologies,particularly in relation to cryptocurrencies,which are central to financial technology research.As discussed in this study,quantum computing applications in finance are based on fundamental quantum physics principles and key quantum algorithms.This review aims to bridge the research gap between quantum computing and finance.We adopt a two-fold methodology,involving an analysis of quantum algorithms,followed by a discussion of their applications in specific financial contexts.Our study is based on an extensive review of online academic databases,search tools,online journal repositories,and whitepapers from 1952 to 2023,including CiteSeerX,DBLP,Research-Gate,Semantic Scholar,and scientific conference publications.We present state-of-theart findings at the intersection of finance and quantum technology and highlight open research questions that will be valuable for industry practitioners and academicians as they shape future research agendas.展开更多
Machine learning(ML)has been increasingly adopted to solve engineering problems with performance gauged by accuracy,efficiency,and security.Notably,blockchain technology(BT)has been added to ML when security is a part...Machine learning(ML)has been increasingly adopted to solve engineering problems with performance gauged by accuracy,efficiency,and security.Notably,blockchain technology(BT)has been added to ML when security is a particular concern.Nevertheless,there is a research gap that prevailing solutions focus primarily on data security using blockchain but ignore computational security,making the traditional ML process vulnerable to off-chain risks.Therefore,the research objective is to develop a novel ML on blockchain(MLOB)framework to ensure both the data and computational process security.The central tenet is to place them both on the blockchain,execute them as blockchain smart contracts,and protect the execution records on-chain.The framework is established by developing a prototype and further calibrated using a case study of industrial inspection.It is shown that the MLOB framework,compared with existing ML and BT isolated solutions,is superior in terms of security(successfully defending against corruption on six designed attack scenario),maintaining accuracy(0.01%difference with baseline),albeit with a slightly compromised efficiency(0.231 second latency increased).The key finding is MLOB can significantly enhances the computational security of engineering computing without increasing computing power demands.This finding can alleviate concerns regarding the computational resource requirements of ML-BT integration.With proper adaption,the MLOB framework can inform various novel solutions to achieve computational security in broader engineering challenges.展开更多
Blockchain technologies have been used to facilitate Web 3.0 and FinTech applications.However,conventional blockchain technologies suffer from long transaction delays and low transaction success rates in some Web 3.0 ...Blockchain technologies have been used to facilitate Web 3.0 and FinTech applications.However,conventional blockchain technologies suffer from long transaction delays and low transaction success rates in some Web 3.0 and FinTech applications such as Supply Chain Finance(SCF).Blockchain sharding has been proposed to improve blockchain performance.However,the existing sharding methods either use a static sharding strategy,which lacks the adaptability for the dynamic SCF environment,or are designed for public chains,which are not applicable to consortium blockchain-based SCF.To address these issues,we propose an adaptive consortium blockchain sharding framework named ACSarF,which is based on the deep reinforcement learning algorithm.The proposed framework can improve consortium blockchain sharding to effectively reduce transaction delay and adaptively adjust the sharding and blockout strategies to increase the transaction success rate in a dynamic SCF environment.Furthermore,we propose to use a consistent hash algorithm in the ACSarF framework to ensure transaction load balancing in the adaptive sharding system to further improve the performance of blockchain sharding in dynamic SCF scenarios.To evaluate the proposed framework,we conducted extensive experiments in a typical SCF scenario.The obtained experimental results show that the ACSarF framework achieves a more than 60%improvement in user experience compared to other state-of-the-art blockchain systems.展开更多
The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneousl...The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.展开更多
As a model for the next generation of the Internet,the metaverse—a fully immersive,hyper-temporal virtual shared space—is transitioning from imagination to reality.At present,the metaverse has been widely applied in...As a model for the next generation of the Internet,the metaverse—a fully immersive,hyper-temporal virtual shared space—is transitioning from imagination to reality.At present,the metaverse has been widely applied in a variety of fields,including education,social entertainment,Internet of vehicles(IoV),healthcare,and virtual tours.In IoVs,researchers primarily focus on using the metaverse to improve the traffic safety of vehicles,while paying limited attention to passengers’social needs.At the same time,Social Internet ofVehicles(SIoV)introduces the concept of social networks in IoV to provide better resources and services for users.However,the problem of single interaction between SIoVand users has become increasingly prominent.In this paper,we first introduce a SIoVenvironment combined with the metaverse.In this environment,we adopt blockchain as the platform of the metaverse to provide a decentralized environment.Concerning passengers’social data may contain sensitive/private information,we then design an authentication and key agreement protocol calledMSIoV-AKAto protect the communications.Through formal security verifications in the real-or-random(ROR)model and using the AVISPA(Automated Validation of Internet Security Protocols and Applications)tool,we firmly verify the security of the protocol.Finally,detailed comparisons are made between our protocol and robust protocols/schemes in terms of computational cost and communication cost.In addition,we implement the MSIoV-AKA protocol in the Ethereum test network and Hyperledger Sawtooth to show the practicality.展开更多
文摘Traditional multi-level security(MLS)systems have the defect of centralizing authorized facilities,which is difficult to meet the security requirements of modern distributed peer-to-peer network architecture.Blockchain is widely used in the field of access control with its decentralization,traceability and non-defective modification.Combining the blockchain technology and the Bell-LaPadula model,we propose a new access control model,named BCBLPM,for MLS environment.The“multi-chain”blockchain architecture is used for dividing resources into isolated access domains,providing a fine-grained data protection mechanism.The access control policies are implemented by smart contracts deployed in each access domain,so that the side chains of different access domains storage access records from outside and maintain the integrity of the records.Finally,we implement the BC-BLPM prototype system using the Hyperledger Fabric.The experimental and analytical results show that the model can adapt well to the needs of multi-level security environment,and it has the feasibility of application in actual scenarios.
基金supported in part by the National Natural Science Foundation of China under Grant 62072351in part by the Key Research Project of Shaanxi Natural Science Foundation under Grant 2023-JCZD-35in part by the open research project of ZheJiang Lab under grant 2021PD0AB01。
文摘Blockchain technology is increasingly popular and has been widely applied in many industrial fields,due to its unique properties of decentralization,immutability,and traceability.Blockchain systems in different fields vary,with different block structures,consensus mechanisms and access permission models.These differences make it hard for different blockchain systems to interoperate with each other,which isolates them.Cross-chain technologies have been developed to solve this isolation problem in order to improve the interoperability of blockchains.Although some surveys on cross-chain technologies can be found,they are unable to keep up with the latest research progress due to their extremely fast pace of development.Moreover,the literature misses general criteria to evaluate the quality of cross-chain technologies.In this paper,a comprehensive literature review of cross-chain technologies is conducted by employing a comprehensive set of evaluation criteria.The preliminaries on blockchain interoperability are first presented.Then,a set of evaluation criteria is proposed in terms of security,privacy,performance,and functionality.The latest cutting-edge works are reviewed based on the proposed taxonomy of cross-chain technologies and their performance is evaluated against our proposed criteria.Finally,some open issues and future directions of cross-chain research are pointed out.
文摘Network marketing is a trading technique that provides companies with the opportunity to increase sales.With the increasing number of Internet-based purchases,several threats are increasingly observed in this field,such as user privacy violations,company owner(CO)fraud,the changing of sold products’information,and the scalability of selling networks.This study presents the concept of a blockchain-based market called ACR-MLM that functions based on the multi-level marketing(MLM)model,through which registered users receive anonymous and confidential rewards for their own and their subgroups’sales.Applying a public blockchain as the ACR-MLM framework’s infrastructure solves existing problems in MLM-based markets,such as CO fraud(against the government or its users),user privacy violations(obtaining their real names or subgroup users),and scalability(when vast numbers of users have been registered).To provide confidentiality and scalability to the ACR-MLM framework,hierarchical identity-based encryption(HIBE)was applied with a functional encryption(FE)scheme.Finally,the security of ACR-MLM is analyzed using the random oracle(RO)model and then evaluated.
基金financially supported by Guangdong Province Basic and Applied Basic Research Fund Project(Grant No.2022B1515250009)Liaoning Provincial Natural Science Foundation-Doctoral Research Start-up Fund Project(Grant No.2024-BSBA-05)+1 种基金Major Science and Technology Innovation Project in Shandong Province(Grant No.2024CXGC010803)the National Natural Science Foundation of China(Grant Nos.52271269 and 12302147).
文摘The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections.
文摘Taxation,the primary source of fiscal revenue,has profound implications in guiding resource allocation,promoting economic growth,adjusting social wealth distribution,and enhancing cultural influence.The development of e-taxation provides a enhanced security for taxation,but it still faces the risk of inefficiency and tax data leakage.As a decentralized ledger,blockchain provides an effective solution for protecting tax data and avoiding tax-related errors and fraud.The introduction of blockchain into e-taxation protocols can ensure the public verification of taxes.However,balancing taxpayer identity privacy with regulation remains a challenge.In this paper,we propose a blockchain-based anonymous and regulatory e-taxation protocol.This protocol ensures the supervision and tracking of malicious taxpayers while maintaining honest taxpayer identity privacy,reduces the storage needs for public key certificates in the public key infrastructure,and enables selfcertification of taxpayers’public keys and addresses.We formalize the security model of unforgeability for transactions,anonymity for honest taxpayers,and traceability for malicious taxpayers.Security analysis shows that the proposed protocol satisfies unforgeability,anonymity,and traceability.The experimental results of time consumption show that the protocol is feasible in practical applications.
基金supported by the National Key R&D Program of China(2022YFB2701500)the National Natural Science Foundation of China(62272385,62311540156)+2 种基金Shaanxi Distinguished Youth Project(2022JC-47)the Key Research and Development Program of Shaanxi(2021ZDLGY06-04)Major Program of Shandong Provincial Natural Science Foundation for the Fundamental Research(ZR2022ZD03).
文摘Adaptor signature,a new primitive that alleviates the scalability issue of blockchain to some extent,has been widely adopted in the off-chain payment channel and atomic swap.As an extension of standard digital signature,adaptor signature can bind the release of a complete digital signature with the exchange of a secret value.Existing constructions of adaptor signatures are mainly based on Schnorr or ECDSA signature algorithms,which suffer low signing efficiency and long signature length.In this paper,to address these issues,we propose a new construction of adaptor signature using randomized EdDSA,which has Schnorr-like structure with higher signing efficiency and shorter signature length.We prove the required security properties,including unforgeability,witness extractability and pre-signature adaptability,of the new adaptor signature scheme in the random oracle model.We conduct a comparative analysis with an ECDSA-based adaptor signature scheme to demonstrate the effectiveness and feasibility of our new proposal.
基金National Natural Science Foundation of China(Nos.42301473,42271424,42171397)Chinese Postdoctoral Innovation Talents Support Program(No.BX20230299)+2 种基金China Postdoctoral Science Foundation(No.2023M742884)Natural Science Foundation of Sichuan Province(Nos.24NSFSC2264,2025ZNSFSC0322)Key Research and Development Project of Sichuan Province(No.24ZDYF0633).
文摘As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes.
文摘The Internet of Things(IoT)has gained substantial attention in both academic research and real-world applications.The proliferation of interconnected devices across various domains promises to deliver intelligent and advanced services.However,this rapid expansion also heightens the vulnerability of the IoT ecosystem to security threats.Consequently,innovative solutions capable of effectively mitigating risks while accommodating the unique constraints of IoT environments are urgently needed.Recently,the convergence of Blockchain technology and IoT has introduced a decentralized and robust framework for securing data and interactions,commonly referred to as the Internet of Blockchained Things(IoBT).Extensive research efforts have been devoted to adapting Blockchain technology to meet the specific requirements of IoT deployments.Within this context,consensus algorithms play a critical role in assessing the feasibility of integrating Blockchain into IoT ecosystems.The adoption of efficient and lightweight consensus mechanisms for block validation has become increasingly essential.This paper presents a comprehensive examination of lightweight,constraint-aware consensus algorithms tailored for IoBT.The study categorizes these consensus mechanisms based on their core operations,the security of the block validation process,the incorporation of AI techniques,and the specific applications they are designed to support.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant 61931005.
文摘Blockchain-based user-centric access network(UCAN)fails in dynamic access point(AP)management,as it lacks an incentive mechanism to promote virtuous behavior.Furthermore,the low throughput of the blockchain has been a bottleneck to the widespread adoption of UCAN in 6G.In this paper,we propose Overlap Shard,a blockchain framework based on a novel reputation voting(RV)scheme,to dynamically manage the APs in UCAN.AP nodes in UCAN are distributed across multiple shards based on the RV scheme.That is,nodes with good reputation(virtuous behavior)are likely to be selected in the overlap shard.The RV mechanism ensures the security of UCAN because most APs adopt virtuous behaviors.Furthermore,to improve the efficiency of the Overlap Shard,we reduce cross-shard transactions by introducing core nodes.Specifically,a few nodes are overlapped in different shards,which can directly process the transactions in two shards instead of crossshard transactions.This greatly increases the speed of transactions between shards and thus the throughput of the overlap shard.The experiments show that the throughput of the overlap shard is about 2.5 times that of the non-sharded blockchain.
文摘The accelerated advancement of the Internet of Things(IoT)has generated substantial data,including sensitive and private information.Consequently,it is imperative to guarantee the security of data sharing.While facilitating fine-grained access control,Ciphertext Policy Attribute-Based Encryption(CP-ABE)can effectively ensure the confidentiality of shared data.Nevertheless,the conventional centralized CP-ABE scheme is plagued by the issues of keymisuse,key escrow,and large computation,which will result in security risks.This paper suggests a lightweight IoT data security sharing scheme that integrates blockchain technology and CP-ABE to address the abovementioned issues.The integrity and traceability of shared data are guaranteed by the use of blockchain technology to store and verify access transactions.The encryption and decryption operations of the CP-ABE algorithm have been implemented using elliptic curve scalarmultiplication to accommodate lightweight IoT devices,as opposed to themore arithmetic bilinear pairing found in the traditional CP-ABE algorithm.Additionally,a portion of the computation is delegated to the edge nodes to alleviate the computational burden on users.A distributed key management method is proposed to address the issues of key escrow andmisuse.Thismethod employs the edge blockchain to facilitate the storage and distribution of attribute private keys.Meanwhile,data security sharing is enhanced by combining off-chain and on-chain ciphertext storage.The security and performance analysis indicates that the proposed scheme is more efficient and secure.
文摘Within the framework of the 2030 Agenda and to achieve the Sustainable Development Goals(SDGs),science,technology and innovation play an even more central role.Building on this foundation,the primary objective of this paper is to explore the potential applications of blockchain in supporting the achievement of these sustainability goals.Starting from a review of the relevant literature on this topic,the main fields in which blockchain can contribute to sustainable development will be identified.The main blockchain applications will then be analyzed and categorized according to these SDGs.This research will then critically present the main blockchain-based projects that emerged in the first stage of the study and were implemented by the United Nations.The main objectives and benefits of each project will be analyzed.This is where the originality of this paper lies.To the best of the author’s knowledge,this is one of the first attempts to present a comprehensive overview of the United Nations’projects related to SDGs 1,2,5,7,9,13,and 16.This paper,which bridges the gap between innovation management and the sustainability field,will contribute to the increasingly current debate on sustainability issues and be beneficial to scholars,practitioners,and policymakers alike.
文摘Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privacy-preserving Web3 scenarios.However,DFL faces incentive and security challenges in the decentralized framework.To address these issues,this paper presents a Hierarchical Blockchain-enabled DFL(HBDFL)system,which provides a generic solution framework for the DFL-related applications.The proposed system consists of four major components,including a model contribution-based reward mechanism,a Proof of Elapsed Time and Accuracy(PoETA)consensus algorithm,a Distributed Reputation-based Verification Mechanism(DRTM)and an Accuracy-Dependent Throughput Management(ADTM)mechanism.The model contribution-based rewarding mechanism incentivizes network nodes to train models with their local datasets,while the PoETA consensus algorithm optimizes the tradeoff between the shared model accuracy and system throughput.The DRTM improves the system efficiency in consensus,and the ADTM mechanism guarantees that the throughput performance remains within a predefined range while improving the shared model accuracy.The performance of the proposed HBDFL system is evaluated by numerical simulations,with the results showing that the system improves the accuracy of the shared model while maintaining high throughput and ensuring security.
基金supported in part by the National Natural Science Foundation of China(62273310)the Natural Science Foundation of Zhejiang Province of China(LY22F030006,LZ24F030009)
文摘The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a blockchain-enabled manufacturing collaboration framework is proposed,with a focus on the production capacity matching problem for blockchainbased peer-to-peer(P2P)collaboration.First,a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain.Second,an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants.Third,a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information.It facilitates automation of the matching process while protecting users'privacy via blockchainbased smart contracts.Finally,simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4%compared to the Bayesian game-based approach,makes all participants profitable,and achieves 90%fairness of enterprises.
文摘This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain technology.By combining the strengths of blockchain and generative AI,the research team aimed to address the timely challenge of safeguarding visual medical content.The participating researchers conducted a comprehensive analysis,examining the vulnerabilities of medical AI services,personal information protection issues,and overall security weaknesses.This multi faceted exploration led to an indepth evaluation of the model’s performance and security.Notably,the correlation between accuracy,detection rate,and error rate was scrutinized.This analysis revealed insights into the model’s strengths and limitations,while the consideration of standard deviation shed light on the model’s stability and performance variability.The study proposed practical improvements,emphasizing the reduction of false negatives to enhance detection rate and leveraging blockchain technology to ensure visual data integrity in medical applications.Applying blockchain to generative AI-created medical content addresses key personal information protection issues.By utilizing the distributed ledger system of blockchain,the research team aimed to protect the privacy and integrity of medical data especially medical images.This approach not only enhances security but also enables transparent and tamperproof record-keeping.Additionally,the use of generative AI models ensures the creation of novel medical content without compromising personal information,further safeguarding patient privacy.In conclusion,this study showcases the potential of blockchain-based solutions in the medical field,particularly in securing sensitive medical data and protecting patient privacy.The proposed approach,combining blockchain and generative AI,offers a promising direction toward more robust and secure medical content management.Further research and advancements in this area will undoubtedly contribute to the development of robust and privacy-preserving healthcare systems,and visual diagnostic systems.
基金funded by the University of Macao(file no.MYRG2022-00162-FST and MYRG2019-00136-FST).
文摘The rapid growth of blockchain and Decentralized Finance(DeFi)has introduced new challenges and vulnerabilities that threaten the integrity and efficiency of the ecosystem.This study identifies critical issues such as Transaction Order Dependence(TOD),Blockchain Extractable Value(BEV),and Transaction Importance Diversity(TID),which collectively undermine the fairness and security of DeFi systems.BEV-related activities,including sandwich attacks,liquidations,transaction replay etc.have emerged as significant threats,collectively generating$540.54 million in losses over 32 months across 11,289 addresses,involving 49,691 cryptocurrencies and 60,830 on-chain markets.These attacks exploit transaction mechanics to manipulate asset prices and extract value at the expense of other participants,with sandwich attacks being particularly impactful.Additionally,the growing adoption of blockchain in traditional finance highlights the challenge of TID,wherein high transaction volumes can strain systems and compromise time-sensitive operations.To address these pressing issues,we propose a novel Distributed Transaction Sequencing Strategy(DTSS)that integrates forking mechanisms with an Analytic Hierarchy Process(AHP)to enforce fair and transparent transaction ordering in a decentralized manner.Our approach is further enhanced by an optimization framework and the introduction of a Normalized Allocation Disparity Metric(NADM)that ensures optimal parameter selection for transaction prioritization.Experimental evaluations demonstrated that the DTSS effectively mitigated BEV risks,enhanced transaction fairness,and significantly improved the security and transparency of DeFi ecosystems.
基金Gerhard Hellstern is partly funded by the Ministry of Economic Affairs,Labour and Tourism Baden-Württemberg in the frame of the Competence Center Quantum Computing Baden-Württemberg(QORA Ⅱ).
文摘The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the exploration of diverse applications arising from this evolving quantum computing paradigm.The scope of the related research is notably diverse.This paper consolidates and presents quantum computing research related to the financial sector.The finance applications considered in this study include portfolio optimization,fraud detection,and Monte Carlo methods for derivative pricing and risk calculation.In addition,we provide a comprehensive analysis of quantum computing’s applications and effects on blockchain technologies,particularly in relation to cryptocurrencies,which are central to financial technology research.As discussed in this study,quantum computing applications in finance are based on fundamental quantum physics principles and key quantum algorithms.This review aims to bridge the research gap between quantum computing and finance.We adopt a two-fold methodology,involving an analysis of quantum algorithms,followed by a discussion of their applications in specific financial contexts.Our study is based on an extensive review of online academic databases,search tools,online journal repositories,and whitepapers from 1952 to 2023,including CiteSeerX,DBLP,Research-Gate,Semantic Scholar,and scientific conference publications.We present state-of-theart findings at the intersection of finance and quantum technology and highlight open research questions that will be valuable for industry practitioners and academicians as they shape future research agendas.
文摘Machine learning(ML)has been increasingly adopted to solve engineering problems with performance gauged by accuracy,efficiency,and security.Notably,blockchain technology(BT)has been added to ML when security is a particular concern.Nevertheless,there is a research gap that prevailing solutions focus primarily on data security using blockchain but ignore computational security,making the traditional ML process vulnerable to off-chain risks.Therefore,the research objective is to develop a novel ML on blockchain(MLOB)framework to ensure both the data and computational process security.The central tenet is to place them both on the blockchain,execute them as blockchain smart contracts,and protect the execution records on-chain.The framework is established by developing a prototype and further calibrated using a case study of industrial inspection.It is shown that the MLOB framework,compared with existing ML and BT isolated solutions,is superior in terms of security(successfully defending against corruption on six designed attack scenario),maintaining accuracy(0.01%difference with baseline),albeit with a slightly compromised efficiency(0.231 second latency increased).The key finding is MLOB can significantly enhances the computational security of engineering computing without increasing computing power demands.This finding can alleviate concerns regarding the computational resource requirements of ML-BT integration.With proper adaption,the MLOB framework can inform various novel solutions to achieve computational security in broader engineering challenges.
基金supported by the National Key Research and Development Program of China (2022YFC3302300)National Natural Science Foundation of China under Grant (No.61873309,No.92046024,No.92146002)Shanghai Science and Technology Project under Grant (No.22510761000)。
文摘Blockchain technologies have been used to facilitate Web 3.0 and FinTech applications.However,conventional blockchain technologies suffer from long transaction delays and low transaction success rates in some Web 3.0 and FinTech applications such as Supply Chain Finance(SCF).Blockchain sharding has been proposed to improve blockchain performance.However,the existing sharding methods either use a static sharding strategy,which lacks the adaptability for the dynamic SCF environment,or are designed for public chains,which are not applicable to consortium blockchain-based SCF.To address these issues,we propose an adaptive consortium blockchain sharding framework named ACSarF,which is based on the deep reinforcement learning algorithm.The proposed framework can improve consortium blockchain sharding to effectively reduce transaction delay and adaptively adjust the sharding and blockout strategies to increase the transaction success rate in a dynamic SCF environment.Furthermore,we propose to use a consistent hash algorithm in the ACSarF framework to ensure transaction load balancing in the adaptive sharding system to further improve the performance of blockchain sharding in dynamic SCF scenarios.To evaluate the proposed framework,we conducted extensive experiments in a typical SCF scenario.The obtained experimental results show that the ACSarF framework achieves a more than 60%improvement in user experience compared to other state-of-the-art blockchain systems.
文摘The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.
基金supported by the Startup Foundation for Introducing Talent of Nanjing University of Information Science and Technology and Natural Science Foundation of Shandong Province,China(Grant no.ZR202111230202).
文摘As a model for the next generation of the Internet,the metaverse—a fully immersive,hyper-temporal virtual shared space—is transitioning from imagination to reality.At present,the metaverse has been widely applied in a variety of fields,including education,social entertainment,Internet of vehicles(IoV),healthcare,and virtual tours.In IoVs,researchers primarily focus on using the metaverse to improve the traffic safety of vehicles,while paying limited attention to passengers’social needs.At the same time,Social Internet ofVehicles(SIoV)introduces the concept of social networks in IoV to provide better resources and services for users.However,the problem of single interaction between SIoVand users has become increasingly prominent.In this paper,we first introduce a SIoVenvironment combined with the metaverse.In this environment,we adopt blockchain as the platform of the metaverse to provide a decentralized environment.Concerning passengers’social data may contain sensitive/private information,we then design an authentication and key agreement protocol calledMSIoV-AKAto protect the communications.Through formal security verifications in the real-or-random(ROR)model and using the AVISPA(Automated Validation of Internet Security Protocols and Applications)tool,we firmly verify the security of the protocol.Finally,detailed comparisons are made between our protocol and robust protocols/schemes in terms of computational cost and communication cost.In addition,we implement the MSIoV-AKA protocol in the Ethereum test network and Hyperledger Sawtooth to show the practicality.