PoEC: A Cross-Blockchain Consensus Mechanism for Governing Blockchain by Blockchain

The research on the governing blockchain by blockchain supervision system is an important development trend of blockchain technology.In this system there is a supervisory blockchain managing and governing the supervised blockchain based on blockchain technology,results in a uniquely cross-blockchain demand to consensus mechanism for solving the trust problem between supervisory blockchain and supervised blockchain.To solve this problem,this paper proposes a cross-blockchain consensus mechanism based on smart contract and a set of smart contracts endorse the crossblockchain consensus.New consensus mechanism called Proof-of-EndorseContracts(PoEC)consensus,which firstly transfers the consensus reached in supervisory blockchain to supervised blockchain by supervisory nodes,then packages the supervisory block in supervisory blockchain and transmits it to the smart contract deployed in the supervised blockchain,finally miners in supervised blockchain will execute and package the new block according to the status of the smart contract.The core part of the consensus mechanism is Endorse Contracts which designed and implemented by us and verified the effectiveness through experiments.PoEC consensus mechanism and Endorse Contracts support the supervised blockchain to join the governing blockchain by blockchain system without changing the original consensus mechanism,which has the advantages of low cost,high scalability and being able to crossblockchain.This paper proves that our method can provide a feasible crossblockchain governance scheme for the field of blockchain governance.

Trusted Blockchain Oracle Scheme Based on Aggregate Signature

With the development of blockchain technology, more and more applications need out-of-chain data. Thus, blockchain oracles have become an important bridge for transferring data on and off the chain. This paper studies the mainstream blockchain oracles scheme, summarizes the shortcomings of the existing schemes and proposes a new blockchain oracle scheme based on BLS (Bohen-Lynn-Shacham) aggregation signature to ensure that off-chain data can be transferred into the blockchain in a trusted and reliable way. Specifically, the scheme uses multiple blockchain oracles to avoid the single point of failure or even a small number of malicious oracles, and improve the credibility of data. At the same time, it not only uses BLS aggregate signature to reduce the storage cost and communication overhead, but also uses commitment mechanisms to ensure the reliability and authenticity of the data. Besides, the simulation results show that the scheme can meet the practical application requirements.

CrowdIoT: The Crowd-Sourcing Test System for IoT Devices Based on Blockchain

In view of some problems existing in traditional software crowdsourcing tests and Internet of Things device tests, we developed a CrowdIoT crowdsourcing test system for the Internet of Things devices based on a block chain. CrowdIoT uses the core technology of blockchain to focus its testing on physical devices on the Internet of Things. CrowdIoT uses two different testing methods for different testing needs: online testing and offline testing. Online remote testing is our key function and research object. By opening the testing interface of Internet of Things devices to testers, testers can test the devices in the CrowdIoT system interface without having to get the hardware. At the same time, CrowdIoT introduced multi-threaded parallel testing technology to solve the conflict problem of multiple testers competing for hardware resources in online testing. Offline testing, as a supplement to online testing, is to send Internet of Things devices to testers with high credibility in deposit guarantee, so that testers can fully test the hardware devices and dig out as many vulnerabilities of the devices as possible. CrowdIoT has its own complete and scientific credibility system, combined with relevant incentive mechanism, consensus mechanism and connection mechanism, which not only effectively solves the centralization problem existing in traditional crowdsourcing testing platforms, but also solves the pain point of the lack of remote testing of Internet of Things devices in the market. Then it solves the problems of equipment limitation and testing cost limits in the field of Internet of Things equipment testing, and provides a platform for security testing and use for the Internet of Things participants.

Blockchain as a Service (BCaaS): A Value Modeling Approach in the Education Business Model

The adoption of Blockchain has caused the organization to rethink how it operates and adds value to its current processes. Some scholars refer to Blockchain as the Black Swan of the 21st century, which will have a greater impact than the introduction of the Internet. Currently, there is little discussion about Blockchain technology and the value model approach and how organizations can close the gap between strategy and operational planning to successfully implement this technology in organizations. This paper explores the relationship and implications of Blockchain technology in relation to the value chain model in education. This paper proposes a value modeling approach for implementing Blockchain in the education sector and demonstrates how a solution works in practice. The novelty of the research will be from both theoretical and practical perspectives. The study will appraise enhancement that can be made within the existing literature on Blockchain and the value chain model, and how the alignment of the two concepts can be used to improve the use of the current value chain model in the education sector.

区块链扩展技术现状与展望

近年来,区块链技术引起广泛关注,其作为一种分布式账本技术,由于具备开放性、透明性和不可篡改性,已经被应用到诸多领域.但随着用户数量和访问需求的大幅增加,现有区块链体系结构可扩展性不足导致的性能瓶颈,制约了区块链技术的应用和推广,如何解决可扩展性问题已成为学术界和工业界关注的热点.对已有的区块链扩展方案进行分析和总结.首先,介绍区块链基本概念和可扩展性问题的由来,定义可扩展性问题并提出衡量可扩展性的指标.其次,给出分类框架,将现有方案按网络扩展、链上扩展、链下扩展3大类进行介绍,通过对不同的区块链可扩展性方案进行分析,比较各自的技术特点并归纳优缺点.最后,对亟待解决的开放性问题进行讨论,展望区块链技术未来趋势.

HBRO: A Registration Oracle Scheme for Digital Rights Management Based on Heterogeneous Blockchains

As the Internet enters the era of big data, massive amounts of data are flooding people’s mobile phones and computers. The emerging self-media industry produces many videos every day, which also exposes many security issues in digital rights management (DRM). The works of original creators can easily be infringed on public networks, and it is urgent to protect the copyright of digital content. Traditional digital rights management (TDRM) has many problems, including unqualified copyright confirmation, difficulty obtaining evidence, long time-consuming, high price, and high centralization. The combination of blockchain technology and digital rights management is one of the most popular blockchain application scenarios, the characteristics of the blockchain match DRM market demand. This paper proposes a registration oracle scheme for digital rights management based on heterogeneous blockchains, HBRO, which uses review and voting as a means to judge whether a work can be registered for copyright. HBRO is more rigorous than TDRM and DDRM in the copyright confirmation stage, rejecting many unnecessary and unqualified contents. In addition, a secure cross-chain solution is used to ensure the integrity and correctness of data transmission on heterogeneous blockchains.

区块链隐私保护技术研究综述

近年来,区块链在学术界和工业界都受到越来越多的关注。在不同应用中部署区块链时,区块链的隐私性仍是备受争议的焦点问题。系统地回顾了当前区块链中隐私保护的方案和机制,给出了区块链的安全性和隐私性的见解。首先,对区块链技术的主要功能、类型和隐私定义进行初步介绍,并分析了其面临的隐私问题;然后,从技术角度出发,将区块链隐私保护技术分为去中心化身份认证、隐私协议、加密技术和混淆技术四大类,以及去中心化身份认证、安全多方计算、差分隐私、同态加密、零知识证明、混币技术、环签名和匿名通信八小类,并分别对它们进行了研究,概述了不同隐私保护技术在许可链与非许可链上的作用机制;最后,对八种隐私保护技术的主要特征和属性进行了定性研究,并探讨了隐私保护技术未来研究方向。研究为区块链开发人员选择合适的隐私保护方案,以及研究人员选择区块链隐私保护研究方向提供借鉴和参考。

具有高价值密度的农业物联网数据区块链压缩存储方案

针对现有区块链物联网体系主要采用链上存储摘要链下保留原始数据的存储方式中链上无法直接获得真实数据的问题,该研究提出了一种具有高价值密度的农业物联网数据区块链压缩存储方案。首先,边缘服务器将收集的同一批数据聚合到同一批事务中;其次,设计离群值可处理的自适应有损压缩方法,在满足用户保真度要求的前提下降低数据冗余;最后,压缩数据上链,实现区块链上物联网数据的高价值密度存储。与现有方案相比,该方案能提高链上存储真实物联网数据的效率。试验结果表明,在使用自适应压缩方法压缩数据时,针对不同的数据集会自适应选取k值,在满足用户重建精度的前提下,获得良好压缩效果,减少链上存储空间,提高了数据价值密度;相对于风速之类频率较高的数据,温湿度、二氧化碳等变化频率较低的数据可以获得较高的压缩比;当假设正常数据压缩比为10:1时,该方案可节省约85%的链上存储空间,相应的价值密度提高了约85%。该研究可为农产品溯源过程中的物联网数据高效存储提供解决方案,为实现分布式农业物联网数据压缩存储提供技术支持。

区块链互操作技术综述

区块链技术被认为是构建价值互联网的基石,然而彼此独立的区块链系统形成了数据、价值孤岛.区块链互操作(也被称为跨链操作)是打破链间壁垒、构建区块链网络的关键技术.在区分狭义与广义区块链互操作的基础上,重新定义狭义区块链互操作,并抽象出跨链读与跨链写两类基本操作;分析总结实现狭义区块链互操作需要解决的3个关键技术问题:跨链信息传输、跨链信任传递、跨链操作原子性保障;系统梳理这3个问题的研究现状,并分别从多角度进行比较;在此基础上,从关键技术问题的角度分析具有代表性的整体解决方案;最后指出几个值得进一步探索的研究方向.

面向实践教学的区块链仿真实验平台构建

区块链应用通常都是基于大型网络的分布式系统,在实际的区块链上进行教学与实验是困难的。该文针对此问题,遵循通用、简约、可扩展的设计原则,构建了区块链仿真实验平台BCES。基于BCES平台,介绍了区块链课程的实践教学,以RBFT共识算法实验为例,详述了算法的设计和BCES平台在实验课程中的应用。教学效果表明,依托BCES平台开展实验,有助于学生理解区块链的底层原理,掌握区块链的理论知识,培养区块链的工程应用能力。

区块链互操作性技术研究进展

区块链技术因其去中心化、高透明度等优良特性引领了新一代数据存储技术的发展,近年来广泛应用于社会治理、金融保险、数字版权等领域。然而,作为一个基于规范和协议的自封闭系统,区块链不同链间无法直接实现数据通信,难以满足跨领域应用的数据共享需求,区块链互操作性技术应运而生。目前,该技术的项目实例分析较少。基于区块链互操作性最新研究成果,系统性总结了近年来互操作技术的代表性方案,并归纳展望了发展前景。首先,按照通信各链的结构差异,将区块链互操作方法划分成同构扩容和异构互操作两种类型;其次,按照技术发展脉络和区块链分层架构,分别介绍两种类型的代表性方法,分析比较了各方法的实现原理和技术细节,归纳总结它们的优缺点;再次,介绍了目前已经实施的区块链互操作性项目研发进展,重点介绍其实现思路、运营模式和现状,并在吞吐量、安全性等多个指标上对比分析其性能;最后,展望了区块链互操作性技术各方向的发展趋势。

联盟链型供应链金融系统的构建、机制和应用

供应链金融有利于缓解企业融资瓶颈,但还有许多理论和实践问题亟须解决。以联盟链为底层技术,将企业、银行和政府部门等参与主体连接在一起,构建联盟链型供应链金融系统,并深入讨论联盟链型供应链金融系统的选型依据、网络架构、运行机制和业务应用。研究表明:(1)相对于公有链和私有链而言,联盟链的部分去中心化、共识信任、不可篡改、智能合约和隐私性等优良特性,能够有效满足供应链金融的业务性、安全性和监管性等要求;(2)采用实用性拜占庭容错算法经过“选主、打包、建块和验证”实现一致共识后将数据上链存储于联盟链分布式总账本,是联盟链型供应链金融系统运行机制的关键;(3)通过采用联盟链型供应链金融系统,供应链上中小企业的融资绩效能够显著提高,即获取资金时间缩短、贷款利率降低和贷款规模扩大。研究结果可以为解决供应链上中小企业的融资难融资贵问题提供新路径和新方案,同时为银行和企业等进行联盟链型供应链金融系统的开发与应用提供现实指引。

营商环境评估的企业级复合区块链构建方法

针对现有营商环境评估系统中企业数据可信度低、易篡改的问题,提出营商环境评估的企业级复合区块链构建方法,采用链上和链下数据协同的方式,对企业原始数据进行存储.改进区块链哈希函数,提出基于SHA256算法的企业原始数据加密方法.引入Key-Value存储模式进行链下基于非易失性内存的Level DB存储,降低系统的通信和存储压力.提出数据链上存储方法,分别将Level DB中的Key值对应存储到基于DAG的Conflux公有链,企业状态数据对应存入到联盟链,为营商环境评估提供可信的存证数据.通过与改进前的Level DB数据库和现有的区块链存储模型进行实验对比,实验结果表明,提出的企业级复合区块链构建方法在读写性能、存储效率两方面均优于现有方法.

智能区块链与区块链智能:构筑DePIN的基础设施智能

去中心化物理基础设施网络是未来数字社会不可或缺的基石,它将传统依赖于集中式控制和管理的物理设施转变为由社区驱动且自主治理的新型基础设施网络,而区块链与人工智能(artificial intelligence,AI)技术的深度融合在其中起到了关键的赋能作用。为此,首先强调有机结合“AI赋能区块链”与“区块链赋能AI”,形成协同增效的双向闭环回路,以构建真正意义上的智能区块链,从而实现区块链智能新范式。其次,提出智能区块链的新型技术架构:一方面,将智能性内嵌至传统区块链架构的每一层,以培育从基础智能到基础设施智能再到应用智能的区块链智能生态;另一方面,为实际智能区块链构建与之对应的人工的智能区块链,并通过二者的虚实反馈与平行执行,形成从静态规则导向到动态适应演进的区块链智能生态。然后,从智慧合约、去中心化身份、知识管理、自主治理等角度辨析区块链智能的核心智能属性。最后,概述区块链智能的典型应用场景及面临的关键挑战。积极推进智能区块链与区块链智能技术的研究与发展,有助于构筑未来数字时代的核心基础设施。

量子信息技术与区块链的融合模式研究

区块链与量子信息技术是近年来兴起的前沿科学技术,受到了业界广泛的关注与研究。其中区块链具有去中心化性质,以区块链为核心技术的应用在金融科技、物联网、民生与政治等诸多领域相继涌现。量子信息技术主要分为量子计算、量子通信、量子测量。其中量子计算的研究主要体现在相较于经典计算的计算优越性,量子计算的运行速度已被证明在解决某些复杂问题上远超经典计算。而在两者迅猛发展的同时,相互之间也存在亟需解决的问题。由于区块链采用的部分经典密码学技术已被证明会被量子计算破解,例如基于非对称密码体制的数字签名,导致区块链的安全受到威胁。针对此问题,已有研究表明,将量子信息技术应用于区块链,可以保护其不受量子攻击。以区块链与量子信息技术相结合为出发点,通过介绍区块链和量子计算的基本结构,以及分析区块链遭受的量子挑战并总结现有的量子解决方案,指出区块链和量子信息技术的融合可以促进区块链在量子时代良好地发展,而这也是不可阻挡的趋势。

基于区块链思维的情报构件资源共享机制研究

[研究目的]运用区块链思维构建情报构件资源共享模型,突破情报分析工作中存在的信息孤岛难题,提高情报工作技能复用性。[研究方法]基于智能合约、共识机制、激励机制等技术提出了基于联盟区块链的情报构件资源共享模型,并对模型组织架构、原型架构、共享流程进行深入探讨。[研究结论]提出的基于区块链的情报构件资源共享模型具有权限可控、共享本体质量可控、自由高效的特点,能够促进情报构件资源的共享,提升情报分析技能的复用性和情报工作的效率,为深化情报构件化思想与情报工程化概念提供可行的方案。

基于区块链技术的等级保护测评要求及测评实践

随着区块链技术的发展,通用的等级保护基本要求不能满足采用区块链技术部署的系统的安全要求。对区块链平台及区块链应用等级保护测评要求进行研究,为采用区块链技术部署的系统的等级保护测评工作开展提供了参考和指引。

区块链链下通道研究综述

近年来,随着比特币、以太坊等数字货币的流行,区块链也受到了各界广泛关注.然而,区块链的三元(可扩展性、安全性、去中心化)悖论限制了其进一步发展,尤其区块链的可扩展性问题致使其交易速率远低于VISA等中心化服务平台.链下通道作为对区块链的扩展,能够有效提高区块链的可扩展性,增大区块链的适用范围.本文首先研究了区块链可扩展性的影响因素,总结了Layer-1扩容和Layer-2扩容的基本概念,并解释了链下通道的基本流程.其次,根据通道中参与者的数量将其分为双方支付通道和多方支付通道.对于双方支付通道,依据实现原理和功能的不同,又将其分为普通支付通道、基于哈希时间锁的支付通道、虚拟通道、支付通道再平衡等类别.另外,介绍了匿名支付通道.进一步,对于每一类通道,总结了其基本流程,分析了典型案例,并指出其存在的优缺点.最后,从应用、监管、奖惩等层面指出了链下通道的未来发展方向.

BSS:一种联盟链存储优化方案

针对联盟链系统普遍采用的全副本存储模式导致存储可扩展性及安全性降低的问题,提出一种基于动态弹性区块散布的存储分片方案.在全网划分若干存储组,同一组内节点以协作方式维护固定数量区块链副本,从而在大幅降低存储开销的同时保证存储可靠性及数据访问性能.具体地,初始散布机制为每个新区块随机分配固定数量初始副本;根据实时区块访问热度变化,动态复制机制弹性增加热区块副本数量,存储优化机制则将冷区块由副本态切换为编码态.根据模拟实验结果,与使用全副本存储模式相比,具有2节点容错能力的存储分片系统可将节点存储开销降低约71%,同时区块访问性能保持在较为良好的水平.