Privacy-Preserving Healthcare and Medical Data Collaboration Service System Based on Blockchain and Federated Learning

As the volume of healthcare and medical data increases from diverse sources,real-world scenarios involving data sharing and collaboration have certain challenges,including the risk of privacy leakage,difficulty in data fusion,low reliability of data storage,low effectiveness of data sharing,etc.To guarantee the service quality of data collaboration,this paper presents a privacy-preserving Healthcare and Medical Data Collaboration Service System combining Blockchain with Federated Learning,termed FL-HMChain.This system is composed of three layers:Data extraction and storage,data management,and data application.Focusing on healthcare and medical data,a healthcare and medical blockchain is constructed to realize data storage,transfer,processing,and access with security,real-time,reliability,and integrity.An improved master node selection consensus mechanism is presented to detect and prevent dishonest behavior,ensuring the overall reliability and trustworthiness of the collaborative model training process.Furthermore,healthcare and medical data collaboration services in real-world scenarios have been discussed and developed.To further validate the performance of FL-HMChain,a Convolutional Neural Network-based Federated Learning(FL-CNN-HMChain)model is investigated for medical image identification.This model achieves better performance compared to the baseline Convolutional Neural Network(CNN),having an average improvement of 4.7%on Area Under Curve(AUC)and 7%on Accuracy(ACC),respectively.Furthermore,the probability of privacy leakage can be effectively reduced by the blockchain-based parameter transfer mechanism in federated learning between local and global models.

A hierarchical blockchain-enabled security-threat assessment architecture for IoV

In Internet of Vehicles(IoV),the security-threat information of various traffic elements can be exploited by hackers to attack vehicles,resulting in accidents,privacy leakage.Consequently,it is necessary to establish security-threat assessment architectures to evaluate risks of traffic elements by managing and sharing securitythreat information.Unfortunately,most assessment architectures process data in a centralized manner,causing delays in query services.To address this issue,in this paper,a Hierarchical Blockchain-enabled Security threat Assessment Architecture(HBSAA)is proposed,utilizing edge chains and global chains to share data.In addition,data virtualization technology is introduced to manage multi-source heterogeneous data,and a metadata association model based on attribute graph is designed to deal with complex data relationships.In order to provide high-speed query service,the ant colony optimization of key nodes is designed,and the HBSAA prototype is also developed and the performance is tested.Experimental results on the large-scale vulnerabilities data gathered from NVD demonstrate that the HBSAA not only shields data heterogeneity,but also reduces service response time.

基于区块链技术的政务BaaS平台设计

阐述区块链技术的去中心化、不可篡改的特性,使其在政务领域得到广泛应用,但给区块链监管带来一系列挑战。为此,设计构建政务区块链BaaS平台,提供统一接口、统一监管以及统一服务。

Learning-Based Joint Service Caching and Load Balancing for MEC Blockchain Networks

Integrating the blockchain technology into mobile-edge computing(MEC)networks with multiple cooperative MEC servers(MECS)providing a promising solution to improving resource utilization,and helping establish a secure reward mechanism that can facilitate load balancing among MECS.In addition,intelligent management of service caching and load balancing can improve the network utility in MEC blockchain networks with multiple types of workloads.In this paper,we investigate a learningbased joint service caching and load balancing policy for optimizing the communication and computation resources allocation,so as to improve the resource utilization of MEC blockchain networks.We formulate the problem as a challenging long-term network revenue maximization Markov decision process(MDP)problem.To address the highly dynamic and high dimension of system states,we design a joint service caching and load balancing algorithm based on the double-dueling Deep Q network(DQN)approach.The simulation results validate the feasibility and superior performance of our proposed algorithm over several baseline schemes.

On Incentive and Coordination Mechanism of Service Outsourcing Based on Principal-Agent Theory and Blockchain Technology

To address the issue of information asymmetry between the two parties and moral hazard among service providers in the process of service outsourcing,this paper builds the Stackelberg game model based on the principal-agent framework,examines the dynamic game situation before the contract being signed,and develops four information models.The analysis reveals a Pareto improvement in the game’s Nash equilibrium when comparing the four models from the standpoint of the supply chain.In the complete information scenario,the service level of the service provider,the customer company’s incentive effectiveness,and the supply chain system’s ultimate profit are all maximized.Furthermore,a coordinating mechanism for disposable profit is built in this study.The paper then suggests a blockchain-based architecture for the service outsourcing process supervision and a distributed incentive mechanism under the coordination mechanism in response to the inadequacy of the principal-agent theory to address the information asymmetry problem and the moral hazard problem.The experiment’s end findings demonstrate that both parties can benefit from the coordination mechanism,and the application of blockchain technology can resolve these issues and effectively encourage service providers.

Research advances on blockchain-as-a-service:architectures,applications and challenges

Due to the complexity of blockchain technology,it usually costs too much effort to build,maintain and monitor a blockchain system that supports a targeted application.To this end,the emerging“Blockchain as a Service”(BaaS)makes the blockchain and distributed ledgers more accessible,particularly for businesses,by reducing costs and overheads.BaaS combines the high computing power of cloud computing,the pervasiveness of IoT and the decentralization of blockchain,allowing people to build their own applications while ensuring the transparency and openness of the system.This paper surveys the research outputs of both academia and industry.First,it introduces the representative architectures of BaaS systems and then summarizes the research contributions of BaaS from the technologies for service provision,roles,container and virtualization,interfaces,customization and evaluation.The typical applications of BaaS in both academic and practical domains are also introduced.At present,the research on the blockchain is abundant,but research on BaaS is still in its infancy.Six challenges of BaaS are concluded in this paper for further study directions.

Intelligent Microservice Based on Blockchain for Healthcare Applications

Nowadays,the blockchain,Internet of Things,and artificial intelligence technology revolutionize the traditional way of data mining with the enhanced data preprocessing,and analytics approaches,including improved service platforms.Nevertheless,one of the main challenges is designing a combined approach that provides the analytics functionality for diverse data and sustains IoT applications with robust and modular blockchain-enabled services in a diverse environment.Improved data analytics model not only provides support insights in IoT data but also fosters process productivity.Designing a robust IoT-based secure analytic model is challenging for several purposes,such as data from diverse sources,increasing data size,and monolithic service designing techniques.This article proposed an intelligent blockchain-enabled microservice to support predictive analytics for personalized fitness data in an IoT environment.The designed system support microservice-based analytic functionalities to provide secure and reliable services for IoT.To demonstrate the proposed model effectiveness,we have used the IoT fitness application as a case study.Based on the designed predictive analytic model,a recommendation model is developed to recommend daily and weekly diet and workout plans for improved body fitness.Moreover,the recommendation model objective is to help trainers make future health decisions of trainees in terms of workout and diet plan.Finally,the proposed model is evaluated using Hyperledger Caliper in terms of latency,throughput,and resource utilization with varying peers and orderer nodes.The experimental result shows that the proposed model is applicable for diverse resourceconstrained blockchain-enabled IoT applications and extensible for several IoT scenarios.

Service-Aware Access Control Procedure for Blockchain Assisted Real-Time Applications

The design of distributed ledger,Asymmetric Key Algorithm(AKA)blockchain systems,is prominent in administering security and access control in various real-time services and applications.The assimilation of blockchain systems leverages the reliable access and secure service provisioning of the services.However,the distributed ledger technology’s access control and chained decisions are defaced by pervasive and service unawareness.It results in degrading security through unattended access control for limited-service users.In this article,a service-aware access control procedure(SACP)is introduced to address the afore-mentioned issue.The proposed SACP denes attended access control for all the service session by identifying the users and service provider availability.The distributed nature of the ledger systems and classication tree learning are combined to determine unattended access.The sole access is determined by summarizing the closed and open access requests and the service provider’s availability and integrity checks.In this process,the learning process classies the secured access request and completed the integrity checks of the current and previous service dissemination.This classication-based access administration reduces the service disconnections and false access rate of the applications.

基于区块链的MaaS数据共享技术体系研究

多种交通系统间的数据采集、整合和共享是出行即服务(MaaS)实现个性化、一体化出行服务的基础,但目前仍存在数据共享意愿弱、数据安全和数据壁垒等问题。本研究在分析MaaS数据共享问题基础上,阐述了区块链技术在MaaS数据共享中的优势,确定了基于联盟链MaaS数据共享的5个数据清单和6个共享步骤,建立了包含区块链标识、区块容量、时间差值、区块头和区块体的区块结构,设计了面向MaaS服务的链上、链下分层数据存储结构。最后,研究以城市级MaaS联程出行为应用案例,从应用层、合约层、网络层、共识层、数据层等5个层级搭建MaaS数据共享联盟链架构,确立面向旅客出行的MaaS数据共享业务流程,为利用区块链技术实现一体化智慧出行服务的数据共享提供技术基础。

An Immutable Framework for Smart Healthcare Using Blockchain Technology

The advancements in sensing technologies,information processing,and communication schemes have revolutionized the healthcare sector.Electronic Healthcare Records(EHR)facilitate the patients,doctors,hospitals,and other stakeholders to maintain valuable data and medical records.The traditional EHRs are based on cloud-based architectures and are susceptible to multiple cyberattacks.A single attempt of a successful Denial of Service(DoS)attack can compromise the complete healthcare system.This article introduces a secure and immutable blockchain-based framework for the Internet of Medical Things(IoMT)to address the stated challenges.The proposed architecture is on the idea of a lightweight private blockchain-based network that facilitates the users and hospitals to perform multiple healthcare-related operations in a secure and trustworthy manner.The efficacy of the proposed framework is evaluated in the context of service execution time and throughput.The experimental outcomes indicate that the proposed design attained lower service execution time and higher throughput under different control parameters.

基于谱聚类的BaaS资源负载均衡调度算法

Fabric作为超级账本的核心项目,以其多通道的设计为用户提供更为隐私的交易空间,为了解决基于分布式架构下的多通道资源负载均衡问题,提出了基于NJW谱聚类的区块链即服务(BaaS)负载均衡调度算法SC-channel。该算法将平台子节点的数量作为划分类簇数量的依据,首先,基于通道采用peer之间的Jaccard系数构造相似矩阵;其次,计算拉普拉斯矩阵,求取前k个特征值和特征向量并将特征向量单位化;最后,用基于数量加权的k-means算法完成聚类。在Kubernetes平台上对这种方法进行验证,并与采用经典k-meansi的NJW算法默认调度算法下的资源负载均衡度做了比较分析。结果表明,采用基于谱聚类的BaaS资源负载均衡调度算法可提高资源利用的均衡程度,增强了平台的可用性与可靠性。

面向智慧水务平台的区块链BaaS关键技术

传统水务数据大多以中心化管理模式为主,但是数据权益涉及到水务集团、设备生产商和保险公司等.在此前提下,数据是否可信,数据传输和存储过程中是否被篡改成为利益涉及方痛点问题与面临的挑战.针对上述问题和挑战,本文结合区块链技术去中心化、不可篡改、可追溯的特性,提出了一种智慧水务区块链BaaS(Blockchain as a Service,区块链即服务)的构建思路和方法,较好地解决了水务数据所面临的可信度低问题.对BaaS服务关键技术:(1)BaaS服务体系架构;(2)智能水表健康数据分布式账本数据模型和Merkle二叉树验证模型;(3)基于双缓冲队列和多区块链节点接入的关键技术,进行了较为详细的阐述.

基于区块链技术的BaaS平台架构及应用

为消除传统电信行业复杂和长链的相互关联操作,解决对账、清算等一致性保证问题,设计了基于区块链的BaaS平台,利用区块链技术将用户和交易等信息上链,共建透明互信的区块链账本,实现电信行业所需的信任、安全和公平机制。

BUES: A Blockchain-Based Upgraded Email System

This paper focuses on the improvement of traditional email system architecture with the help of blockchain technology in the existing network environment. The improved system architecture can better improve the security and stability of the system. The email content is extracted and stored in the blockchain network to achieve regulatory traceability between the email service provider and the higher-level organization. In turn, A Blockchain-based Upgraded Email System(BUES) is proposed. The defects of the existing traditional email system are addressed. Firstly, the threat model of the traditional email system is analyzed, and solutions are proposed for various threats. Then a system architecture consisting of the blockchain network, email servers, and users are constructed. The implementation of BUES is carried out, and the related experimental process and algorithm steps are given. After the experimental analysis, it is shown that BUES can ensure the security, reliability, efficiency, and traceability of email transmission.

基于BaaS的高校数据治理系统模型研究

文章通过文献分析法总结归纳国内外BaaS(区块链即服务)相关研究现状,尝试从主体、客体、功能三方面对BaaS应用于高校数据治理的适用性进行分析,并对其优势从五方面进行论述,最后构建一种基于BaaS的高校数据治理系统模型,以期为相关理论研究与实际工作提供参考。

一体化区块链BaaS平台的设计与实现

针对区块链应用的性能和功能需求,研究了一体化BaaS平台的设计理念,提出了可支持快速联盟业务链构建的BaaS总体架构,从高可用计算技术、应用标准以及接入规范等方面研究了BaaS平台的设计和实现方法。最后通过50条区块链中的用户登录、数据上链和链上数据查询三个场景验证了所提方案的可行性。

基于CP-ABSE的农机社会化服务联盟链隐私匹配方案

针对多个农机社会化服务平台联合,实现跨平台任务匹配中存在的敏感数据泄露和集中式服务器不可信问题,该研究提出了基于密文策略属性基可搜索加密(ciphertext-policy attribute-based searchable encryption,CP-ABSE)的农机社会化服务联盟链隐私匹配方案。该方案基于联盟链构建农机社会化服务联合平台,为多平台数据共享提供去中心化的可信环境;基于CP-ABSE技术实现跨平台的任务匹配,支持对任务密文数据的检索以及细粒度的访问控制,保护作业任务发布方和农机手的敏感数据;使用智能合约实现农田作业任务与农机手之间的匹配服务,避免集中式服务器存在的单点故障和恶意违规操作等问题。安全性分析表明,该方案能够保证数据的完整性、机密性以及匹配结果的可信性。基于Hyperledger Fabric构建了一个原型系统,测试结果表明,当全局属性数量为200时,系统构建和私钥生成的运行时间分别约8和2.5 s,搜索令牌生成与数据加密的计算开销分别为60和80 ms,匹配智能合约平均时延约为250 ms。该方案破解了农机社会化服务平台间的“数据孤岛”问题,对于促进农机社会化服务的推广具有重要的意义。

基于区块链的可信SOA架构

在传统服务架构(Service-Oriented Architecture,SOA)中,Web Service提供者将其服务描述注册在注册中心,供服务消费者进行服务发现和服务调用。尽管该架构可以提供松散的服务调用,但是缺乏争议解决机制,使得互不信任的服务消费者和提供者之间的服务可信调用得不到保证。区块链技术在去中心化和抗篡改等方面具有显著的优势,可被合理地应用在传统SOA中,以解决服务可信问题。结合传统SOA架构和区块链技术,提出了一种基于区块链的可信SOA架构,实现可信的服务调用。在一次服务可信调用过程中,服务消费者进行参数加密并将其发送给目标服务提供者;服务提供者接收加密参数并对其完成解密;服务提供者完成服务执行并对输出结果完成加密;最后服务提供者在将加密结果发送给服务消费者的同时完成可信凭证的构造与上链。在上述基础上,当发生服务纠纷时,将触发裁决智能合约,正确处理服务纠纷。实验结果表明,与传统的调用相比,所提方法能够在保证大部分服务可信调用时间增长率不大于30%的前提下,正确处理服务提供者和请求者之间的服务纠纷。

面向用户需求挖掘的去中心化异步联邦LDA算法

在云制造服务场景下,服务组合开发者往往需要基于用户的制造需求进行定制化服务组合开发。随着隐私保护法律法规的相继颁布,常用的用户需求挖掘算法如隐狄利克雷分布(LDA)主题模型已难以在实际中使用。本文通过对区块链和联邦学习技术交叉研究,提出了面向用户需求挖掘的去中心化异步联邦隐狄利克雷分布算法(DAFedLDA)。在DAFedLDA中,本文基于对等分布式LDA,进一步提出了基于多链的权限控制机制(MCACS)以及基于随机丢弃的数据贡献质量监控机制(RDDMS)。本文基于ProgrammableWeb.com实例进行了一系列实验,验证了算法的有效性。

能源区块链的跨链服务安全技术研究进展

在“双碳”目标推动下,能源产业数字化转型势在必行.随着区块链在能源行业数字化转型应用和发展,能源区块链概念逐渐形成共识,它是区块链与能源互联网深度融合的产业新形态,可助力能源主体之间的高效协作,为绿色低碳等创新业务模式提供技术支撑与服务.能源区块链的规模化发展离不开多层次跨链技术的突破,但能源区块链的跨链服务还面临着许多问题.将目前能源区块链领域的研究现状分为5类,即能源区块链架构、智能合约应用、跨链技术、区块链节点管理和区块链隐私保护,针对这5个方向分别总结相关研究工作,详细梳理出各研究方案的原理、优势与不足;然后,为促进能源区块链的跨链服务安全技术的发展,根据能源区块链的现实需求,结合监管机制与共识机制提出多层次跨链协同监管的能源区块链架构;最后,总结出能源区块链跨链服务安全技术中亟待解决的问题,并提出区块链在能源领域的研究展望.