Applying blockchain-based method to smart contract classification for CPS applications

Smart contract has been the core of blockchain systems and other blockchain-based systems since Blockchain 2.0. Various operations on blockchain are performed through the invocation and execution of smart contracts. This leads to extensive combinations between blockchain, smart contract, Internet of Things (IoT) and Cyber-Physical System (CPS) applications, and then many blockchain-based IoT or CPS applications emerge to provide multiple benefits to the economy and society. In this case, obtaining a better understanding of smart contracts will contribute to the easier operation, higher efficiency and stronger security of those blockchain-based systems and applications. Many existing studies on smart contract analysis are based on similarity calculation and smart contract classification. However, smart contract is a piece of code with special characteristics and most of smart contracts are stored without any category labels, which leads to difficulties of smart contract classification. As the back end of a blockchain-based Decentralized Application (DApp) is one or several smart contracts, DApps with labeled categories and open source codes are applied to achieve a supervised smart contract classification. A three-phase approach is proposed to categorize DApps based on various data features. In this approach, 5,659 DApps with smart contract source codes and pre-tagged categories are first obtained based on massive collected DApps and smart contracts from Ethereum, State of the DApps and DappRadar. Then feature extraction and construction methods are designed to form multi-feature vectors that could present the major characteristics of DApps. Finally, a fused classification model consisting of KNN, XGBoost and random forests is applied to the multi-feature vectors of all DApps for performing DApp classification. The experimental results show that the method is effective. In addition, some positive correlations between feature variables and categories, as well as several user behavior patterns of DApp calls, are found in this paper.     

基于属性密码体制的区块链安全技术研究进展

区块链是一种集合了分布式存储、点对点传输、共识机制、密码学算法和智能合约等关键技术的分布式账本,具有去中心化、不可篡改、透明化等特性.近年来区块链技术的安全性问题逐渐显露,阻碍了区块链应用的发展.本文介绍了区块链的基本概念与安全模型,分析了区块链的安全性问题;然后,基于属性密码体制,从访问控制、密钥管理、数据隐私保护这三个方面分析了区块链安全技术的各类研究,论述了主要的解决方案的特点;最后,总结了基于属性密码体制的区块链安全技术研究进展,并对未来的研究工作进行了讨论.     

基于区块链的社会物联网可信服务管理框架

针对当前社会物联网可信服务管理中存在的中心化程度高、交易不透明和易受攻击等问题,提出了一种基于区块链的社会物联网可信服务管理框架。该框架通过区块链的去中心化特性在服务请求者和服务提供者之间直接建立信任关系,利用智能合约产生并管理新的交易,实现交易过程透明化并减少管理维护成本。同时,区块链的共识机制可用于交易验证并防范恶意攻击和篡改,减少网络攻击和恶意节点的欺骗。最后,分析了该框架在实际构建中面临的主要挑战。     

Survey on blockchain-based non-fungible tokens: History,technologies, standards,and open challenges

This paper presents a survey of non-fungible tokens (NFTs), including its history, technologies, standards, and challenges in their development. An NFT is a unique digital entity that is created and maintained using blockchain technology. Each NFT is identified using a unique smart contract and a token ID, so the whole history of the NFT can be globally identified by its address and token ID. The blockchain information indelibly identifies the current owner of any asset, previous owners, and original creator. NFTs are used to manage ownership of digital and physical assets and cryptocurrencies. The prices of popular NFTs have become very high, and the market for them has overheated in recent years. NFT technology and its ecosystem have evolved since Quantum, the first NFT, was stored in the Namecoin blockchain. Ethereum has become the main platform for NFT projects because it provides support for smart contracts. Currently, almost all NFT projects are launched on the Ethereum blockchain. NFT has two major standards called ERC-721 and ERC-1155, which have had important functions in the development of NFT. Starting with these two standards, other standards for NFT continue to emerge; they expand the functionality of NFT such as by adding utility. However, NFT is a very early technology, and it has not been long after the NFT concept was created and used. So there are several challenges for further improving NFT technology, in terms of usability, interoperability, and evolution. This paper presents a survey of NFT, including its history, technologies, standards, and challenges of NFT.     

A systematic literature review of blockchain cyber security

Since the publication of Satoshi Nakamoto's white paper on Bitcoin in 2008, blockchain has (slowly) become one of the most frequently discussed methods for securing data storage and transfer through decentralized, trustless, peer-to-peer systems. This research identifies peer-reviewed literature that seeks to utilize blockchain for cyber security purposes and presents a systematic analysis of the most frequently adopted blockchain security applications. Our findings show that the Internet of Things (IoT) lends itself well to novel blockchain applications, as do networks and machine visualization, public-key cryptography, web applications, certification schemes and the secure storage of Personally Identifiable Information (PII). This timely systematic review also sheds light on future directions of research, education and practices in the blockchain and cyber security space, such as security of blockchain in IoT, security of blockchain for AI data, and sidechain security.     

Task offloading based on deep learning for blockchain in mobile edge computing

Blockchain is an advanced technique to realize smart contracts, various transactions, and P2P crypto-currencies in the e-commerce society. However, the traditional blockchain does not consider a mobile environment to design a data offloading of the blockchain such that the blockchain results in high computational cost and huge data propagation delay. In this paper, to remedy the above problem, we propose a scalable blockchain and a task offloading technique based on the neural network of the mobile edge computing scenario. Experimental results show that our approach is very scalable in the mobile scenario.

     

基于区块链技术的计费清结算平台的设计与研究

分析了电信运营商的国内漫游清结算业务现状以及5G来临之后所面临的问题和挑战,介绍了以分布式账本、智能合约为代表的区块链技术,制定了基于区块链技术的国内清结算平台解决方案,并从清结算平台的逻辑架构、业务架构、交易流程和可扩展性探究等方面做了详尽的阐述。最后,基于国内清结算平台的落地方案,结合新形势下的业务发展需求,提供了佣金结算、网间结算和国际漫游结算的设计思路。     

De-anonymizing Ethereum blockchain smart contracts through code attribution

Blockchain users are identified by addresses (public keys), which cannot be easily linked back to them without out-of-network information. This provides pseudo-anonymity, which is amplified when the user generates a new address for each transaction. Since all transaction history is visible to all users in public blockchains, finding affiliation between related addresses undermines pseudo-anonymity. Such affiliation information can be used to discriminate against addresses linked with undesired activities or can lead to de-anonymization if out-of-network information becomes available. In this work, we propose an approach to undermine pseudo-anonymity of blockchain transactions by linking together addresses that were used to deploy smart contracts, which were produced by the same authors. In our approach, we leverage stylometry techniques, widely used in the social science field for attribution of literary texts to their corresponding authors. The assumption underlying authorship attribution is the existence of a distinctive writing style, unique to an author and easily distinguishable from others. Drawing an analogy between literary text and smart contracts' source code, we explore the extent to which unique features of source code and byte code of Ethereum smart contracts can represent the coding style of smart contract developers. We show that even a small number of representative features leads to a sufficiently high accuracy in attributing smart contracts' code to its deployer's address. We further validate our approach on real-world scammers' data and Ponzi scheme-related contracts. Additionally, we provide an algorithm to extract distinctly contributing features per an entire dataset or per specific authors. We use this algorithm to extract and explore such features in our dataset and in the Ponzi scheme-related dataset.     

Blockchain and smart contracts for higher education registry in Brazil

The validation of academic credits and issuance of academic degree certificates in the Brazilian education system currently occurs in a semi or completely noncomputerized way. The actual digitization of this system could make it more secure and decrease bureaucracy in terms of document validation, saving in storage and labor. Due to the recent increase in forgeries and loss of records, it is paramount that this process becomes more transparent and reliable for all involved parties. This article presents a proposal and an implementation for the digitization of degree certificates and academic credits for higher education in the Brazilian education system. A transparent model based on blockchain is proposed, in which higher education institutions register students and their academic credits in a chain of records using the Brazilian Public Key Infrastructure for identity management. This information, associated with smart contracts, enables the reliable and decentralized issuance of degree certificates through the validation of a historical database and the triggering of transactions using smart contracts. The focus of this article is the demonstration of an experiment that validates this proposal.     

Blockchain-inspired lightweight trust-based system in vehicular networks

A decentralized application runs on the blockchain network without the intervention of a central authority. Transparency in transactions and security in vehicular networks are the issues for central systems. The proposed system uses blockchain-based smart contracts, which eliminate the requirement for any third-party verification. Additionally, with signature verification and reduced overhead, smart contracts also help in a fast and secure transaction. This study suggests a trust-based system paradigm where certificate authority (CA) is employed for vehicle registration. We also propose a blockchain-based system that provides efficient two-way authentication and key agreement through encryption and digital signatures. The analysis of the proposed model reveals that it is an efficient way of establishing distributed trust management, which helps in preserving vehicle privacy. The proposed scheme is tested in Automated Validation of Internet Security-sensitive Protocols (AVISPA), and security parameters verification in Network Simulator 2(NS2) also shows that the proposed scheme is more effective in comparison with existing schemes in terms of authentication cost, storage cost, and overhead.     

区块链网络安全保障:攻击与防御

随着区块链技术的迅猛发展,区块链系统的安全问题正逐渐暴露出来,给区块链生态系统带来巨大风险。通过回顾区块链安全方面的相关工作,对区块链潜在的安全问题进行了系统的研究。将区块链框架分为数据层、网络层、共识层和应用层4层,分析其中的安全漏洞及攻击原理,并讨论了增强区块链安全的防御方案。最后,在现有研究的基础上展望了区块链安全领域的未来研究方向和发展趋势。     

联盟链技术测试观察与分析

对可信区块链推进计划2019年度开展的功能测试、性能测试、BaaS测试、垂直行业(供应链金融)测试的测试情况进行整理披露,提出十大测试观察,涵盖联盟链的底层架构、共识算法、账本数据库、加密算法、智能合约、治理、隐私保护、跨链、性能测试观察以及供应链金融测试观察,以供业界参考。     

区块链助力电信网络反欺诈协同治理

电信网络欺诈案线索分布广、破坏跨度大、受害人群多,给案件侦破带来了难度。大数据、人工智能等技术推动了精准化侦办,但技术的不当使用也会带来个人隐私泄露、银行卡被盗刷盗用的风险。探索了基于区块链的电信网络反欺诈协同治理,进行了核心能力和反欺诈人群分析,利用区块链的智能合约和密码共识,保证了电信数据的不可篡改和安全共享,进行了反欺诈协同治理的逻辑设计,为基于区块链的电信网络反欺诈协同治理的进一步落地应用提供了思路。     

智能电网数据保护框架的建构

智能电网系统的网络安全问题越来越受到学术界的关注,为此提出了许多网络攻击的检测和防御方法,以增强智能电网系统的鲁棒性。文中提出了一种新的基于分布式区块链的保护框架,以增强智能电网系统抵御网络攻击的能力。该框架将智能电表作为分布式网络中的节点,将电表测量数据封装为块,利用区块链技术来实现对智能电表计量数据的分布式共识。性能分析的结果验证了该保护框架的有效性。     

基于区块链的电子政务数据共享设计研究

区块链技术提供了链上数据不可篡改、共享可查的链上记录等能力,提供了多方信任和数据共享机制。因此,区块链技术可以实现各个政府部门之间的数据共享访问验证。为此,针对“一网通办”电子政务数据共享的需求,深入的对区块链技术进行研究,将电子政务数据存储在区块链上,采用主链和子链的分层架构来增强了权限管理、安全控制等机制,基于Hyperledger Fabric1.4来设计的,并对智能合约和区块链的存储的核心模块的开发进行阐述。     

Blockchain-based data transmission control for Tactical Data Link

Tactical Data Link (TDL) is a communication system that utilizes a particular message format and a protocol to transmit data via wireless channels in an instant, automatic, and secure way. So far, TDL has shown its excellence in military applications. Current TDL adopts a distributed architecture to enhance anti-destruction capacity. However, It still faces a problem of data inconsistency and thus cannot well support cooperation across multiple militarily domains. To tackle this problem, we propose to leverage blockchain to build an automatic and adaptive data transmission control scheme for TDL. It achieves automatic data transmission and realizes information consistency among different TDL entities. Besides, applying smart contracts based on blockchain further enables adjusting data transmission policies automatically. Security analysis and experimental results based on simulations illustrate the effectiveness and efficiency of our proposed scheme.     

Integration of Internet of Things and blockchain technology in healthcare domain: A systematic literature review

Healthcare is a vitally important field in the industry and evolving day by day in the aspect of technology, services, computing, and management. Its potential significance can be increased by incorporating Internet of Things (IoT) technology to make it smart in the aspect of automating activities, which is then further reformed in the healthcare domain with the help of blockchain technology. Blockchain technology provides many features to IoT-based healthcare domain applications such as restructuring by securing traditional practices, data management, data sharing, patient remote monitoring, and drug analysis. In this study, a systematic literature review has been carried out in which a total of 52 studies were selected to conduct systematic literature review from databases PubMed, IEEE Access, and Scopus; the study includes IoT technology and blockchain integration in healthcare domain-related application areas. This study also includes taxonomy that mentions the aspects and areas in healthcare domain incorporating the traditional system with the integration of IoT and blockchain to provide transparency, security, privacy, and immutability. This study also includes the incorporation of related sensors, platforms of blockchain, the objective focus of selected studies, and future directions by incorporating IoT and blockchain in healthcare domain. This study will help researchers who want to work with IoT and blockchain technology integration in healthcare domain.     

互联网数据安全与区块链技术的交叉研究

随着互联网的快速发展,互联网数据的安全问题日益凸显,如数据泄露、隐私问题、中心化管理弊端、黑客攻击、数据篡改等。为解决这一问题,文中探讨了区块链技术在互联网数据安全中的潜在应用。通过分析区块链的基本原理,包括去中心化、不可篡改、智能合约等特性,以期为构建更加安全、透明和高效的互联网数据管理体系提供新的思路。     

Can blockchain link the future?

Recently, decentralization has been extensively explored by researchers. Blockchain, as a representation of decentralized technology, has attracted attention with its unique characteristics, such as irrevocability and security. Consequently, herein, we introduce cutting-edge blockchain technologies from four directions: blockchain system, consensus algorithms, smart contract, and scalability. Subsequently, we analyze the current lack of consensus mechanism, fault tolerance, and block capacity of the blockchain, and the integration of blockchain into 5G/6G mobile communication. Furthermore, we discuss the possible applications of blockchain in intellectual property protection, the Internet of Things, digital twins, standardization, and epidemic prevention and control. Finally, explore the impacts and solutions of blockchain on human society beyond technology.