区块链技术专刊序言(中英文)

Abstract

区块链是一种去信任化的分布式计算范式, 按照时间顺序将数据区块以顺序相连的方式组合成一种链式数据结构, 使用密码学方法, 实现数据的一致存储、不可篡改和防止抵赖. 作为一种在不可信的竞争环境中低成本建立信任的新型计算范式和协作模式, 区块链正在改变诸多行业的应用场景和运行规则, 在数字货币、金融服务、物联网、智能制造、医疗健康、征信等领域得到高度的重视. 实际上, 任何高价值数据的管理、流通和共享都可以使用区块链.

密码技术是区块链的关键技术之一, 不仅关系到区块链的安全与效率, 而且也是实现区块链具体应用的基本手段. 安全与隐私一直是区块链技术应用过程中的重要评估对象, 对此, 密码技术起到了至关重要的作用. 如哈希函数、数字签名保证了区块链技术的不可篡改性和不可伪造性, 环签名、同态加密和零知识证明等在不同程度上保证了用户的隐私性. 在密码技术保证区块链安全应用的同时, 区块链又促进了密码技术的发展. 如区块链重新引起了对安全多方计算、密钥保护与管理、抗量子攻击等密码技术的研究热潮.

为了推动区块链技术的发展与研究, 保证区块链的安全应用, 进一步促进密码理论与应用研究, 本刊通过广泛征稿和约稿, 组织了本期``区块链技术''专刊, 本期共包括11 篇论文.

综述性论文3篇. 斯雪明等人的论文《区块链安全研究综述》阐释了区块链技术架构, 梳理了不同层次下所面临的安全问题, 包括区块链技术面临的各类风险以及各类攻击手段. 比特币的安全问题引起了人们的更多关注, 出现了许多攻击方法. 韩健等人的论文《比特币挖矿攻击研究》介绍了比特币挖矿的常见攻击, 分析了攻击的基本原理、威胁危害, 梳理了一些现存的应对攻击的方案. 区块链理论研究是区块链健康发展的基础. 单进勇等人的论文《区块链理论研究进展》介绍了区块链运行机制、基本特征、关键技术、技术挑战等. 给出了区块链的形式化定义, 总结了热点研究方向, 以及相关密码技术、安全性分析、共识机制、隐私保护、可扩展性等, 突出了密码技术在区块链中的重要作用. 指出特殊数字签名、零知识证明、同态密码、安全多方计算等在区块链中的潜在应用价值, 也介绍了区块链所面临的诸如吞吐量低、延迟高、耗能高等一系列技术瓶颈.

区块链技术研究论文4篇. 区块链通常具有不可更改的基本特征, 李佩丽等人的论文《可更改区块链技术研究》提出了一种可更改区块链方案, 用以解决联盟链中需要对出错的历史记录做出修改和响应的问题. 林齐平等人的论文《基于超奇异同源的鉴别方案》构造了一种基于超奇异椭圆曲线的鉴别方案, 以抵抗量子计算机的攻击. 共识机制是区块链或分布式账本技术中的关键组件之一. 郭兵勇等人的论文《一个高传输效率的多值拜占庭共识方案》提出了一种改进的Byzantine fault tolerant (BFT)协议方案. 每个节点只广播自己建议共识的消息哈希值. 在达成哈希列表的共识后, 缺少相关消息的节点向多数拥有该消息的节点请求消息原文并最终完成共识. 张凡等人的论文《基于Borromean环签名的隐私数据认证方案》提出了改进的隐私数据认证方案, 对保密的交易金额进行范围证明, 以提高验证效率.

区块链应用研究论文4篇. 王志鹏等人的论文《一种清算结算区块链设计》给出了一种理论上可对所有数据公开的区块链进行清算结算的设计思路, 提出了一种清算结算设计方案, 可为用户链提供数据备份, 使得用户链遭受恶意攻击后可通过该机制大致恢复原有的交易记录. 苑博奥等人的论文《基于区块链的公平多方不可否认协议》基于公开链结构, 提出了一个完全无 trusted third party (TTP)参与的多方不可否认协议, 并用形式化分析方法证明了协议满足不可否认性、公平性和时限性. 高莹等人的论文《基于区块链的高效公平多方合同签署协议》结合可验证加密签名和聚合签名, 提出了无证书的聚合可验证加密签名方案, 给出了一个具体构造. 孙韵秋等人的论文《基于区块链技术的高校成绩管理系统》通过区块链数据防篡改和可信时间戳, 以解决高校成绩在中心化存储方式下容易被泄露和篡改的问题.

相对于其它成熟的信息技术, 区块链的研究仍处于初级阶段, 在系统稳定性、应用安全性、业务模式等方面尚待研究与完善. 希望读者能够通过本专刊对区块链技术有一个更全面更系统的了解, 提高对区块链的认识水平.

专刊责任编委: 冯登国, 欧阳永贵

Alternate abstract:

Blockchain is a kind of de-trusted distributed computing paradigm, sequentially connects data blocks in chronological order that constitutes a kind of chained data structure, and uses cryptographic techniques to realize consistent storage, unmanipulability, and non-repudiation of data. As a new type of computing paradigm and cooperating mode whose trust is built with lower cost in untrusted competitive environment, blockchain has been changing application scenarios and operating rules in many industries, and it is highly valued in the areas of digital currency, financial service, Internet of Things, intelligent manufacturing, medical health, credit reporting, and so on. In fact, the management, circulation, and sharing of any high-valued data can use blockchains. Cryptographic technique is the core of blockchains. It concerns not only the security and efficiency, but also the concrete applications of blockchains. Cryptographic techniques play specifically important role in guaranteeing the security and privacy, two crucial factors for evaluating blockchains. For example, Hash functions and digital signatures assure the unmanipulability and unforgeability of blockchains; ring signatures, homomorphic encryption, zero-knowledge proofs, etc. protect the users' privacy in different extent. While cryptographic techniques guarantee the security of blockchain applications, the research on blockchain in turn promotes the development of many cryptography branches, e.g., secure multi-party computation, key protection and management, post-quantum cryptography, and so on. To promote the development and research of blockchain, to guarantee the security of the applications of blockchains, and to further facilitate the research of cryptographic theory and applications, Journal of Cryptologic Research organized the special issue on ''Blockchain Technology'' by calling and inviting for papers widely, and 11 papers are selected into this special issue after the peer review process. Three review articles are included in this special issue. ''Survey on Security of Blockchain'' by Si Xue-Ming et al. describes the architecture of the blockchain technology. It lays out the security issues on different hierarchies, including the various risks faced by the blockchain technology and different types of attacks. The security of Bitcoin has attracted more attention, and many attacks have been proposed. ''Research on Mining Attacks in Bitcoin'' by Han Jian et al. elaborates the common attacks on Bitcoin mining, analyzes the basic approach, threats and damages of the attacks, and describes some known countermeasures. Research of blockchain theory is the foundation of sound development of blockchains. The paper entitled ''Research Progress on Theory of Blockchains'' by Shan Jin-Yong et al. firstly introduces the operating mechanism, basic characteristics, key technologies, and technical challenges of blockchains. Then, it gives the formal definition of blockchains, summarizes the research hotspots, related cryptographic techniques, security analysis, consensus mechanism, privacy protection, scalability, etc. This paper also emphases on the importance of cryptographic techniques in blockchains, points out the potential application values of special digital signatures, zero-knowledge proofs, homomorphic cryptography, and secure multi-party computation in blockchains, and describes a series of technical bottlenecks faced by blockchains such as low throughput, high latency, high energy consumption, etc. There are 4 research articles on blockchain technology. Blockchain usually provides the unmanipulability. Li Pei-Li et al. put forward a manipulable blockchain scheme in ''Research on Fault-correcting Blockchain Technology'', to solve the issue in alliance chains that the error records need to be modified and responded. In ''Identification Scheme Based on Supersingular Isogenies'', Lin Qi-Ping et al. construct an identification scheme based on supersingular isogenies to resist quantum attacks. Consensus mechanism is one of key building blocks in blockchains or in distributed ledger. ''Multi-valued Byzantine Consensus Scheme with High Transmission Efficiency'' by Guo Bing-Yong et al. proposes an improved Byzantine fault tolerant (BFT) protocol. In their improved protocol, each node only broadcasts the Hash digests of messages that it recommended for consensus. After the consensus of Hash list was agreed, the nodes which lack of related message request the missing messages from a majority of nodes which have them, and finally achieve the consensus. Zhang Fan et al. put forward an improved privacy data authentication scheme in ''Privacy Data Authentication Schemes Based on Borromean Ring Signature''. The proposed scheme provides the range proof for the secret amount of transactions to improve the verification efficiency. Four research articles on blockchain applications are also included in this special issue. In ''Design of Blockchain for Clearing and Settlement'', Wang Zhi-Peng et al. propose a design approach which could theoretically clear and settle for all the blockchains of open data; put forward a scheme for clearing and settlement. This scheme can back up the data for user chains, and can approximately restore the original transaction records after the user chain collapses. Based on the structure of public chains, ''Fair Multi-party Non-repudiation Protocol Based on Block Chain'' by Yuan Bo-Ao et al. proposes a multi-party non-repudiation protocol without trusted third party (TTP), and proves that the protocol satisfies non-repudiation, fairness, and timeliness through formal analysis. Combining verifiably encrypted signatures (VESs) with aggregated signatures, Gao Ying et al. propose the certificateless aggregate VES scheme (CLAVES) in ''Efficient Multi-party Fair Contract Signing Protocol Based on Blockchains'', give a concrete construction. ''University Score Management System Based on Blockchain Technology'' by Sun Yun-Qiu et al. utilizes the tamper-resistant feature and trusted timestamp of blockchain data to solve the problem of information leakage and manipulating of centrally stored academic grades in universities. Compared with other highly developed information technology, blockchain research is still in the preliminary stage. Its systematic stability, application security, business mode, etc. need to be further studied and improved. The purpose of this special issue is to present a comprehensive picture of blockchain technology, we hope that our fellow readers may better understand the blockchains systematically through this special issue, thus to promote the research and application of blockchain technology. Guest Editor: FENG Deng-Guo, OUYANG Yong-Gui