Research Progress and Prospect of Ring Signatures

doi:10.3778/j.issn.1673-9418.2210022

Abstract

Abstract: As a special group signature, ring signature has been widely used in anonymous voting, anonymous deposit and anonymous transaction because it can not only complete the signature without the cooperation of ring members, but also ensure the anonymity of the signer. Firstly, this paper takes time as the main line, divides the development of ring signatures into different stages, and divides ring signatures into threshold ring signatures, linkable ring signatures, ring signatures with revocable anonymity, and repudiable ring signatures according to the attributes in each stage. Through the analysis of the development process of ring signature, it can be seen that the research progress of ring signature in the field of threshold ring signature and linkable ring signature is prominent, and their application fields are also the most extensive. In the post-quantum era, cryptographic schemes based on traditional number theory problems such as large integer factorization and discrete logarithms are no longer secure, and lattice-based public key cryptography has become the best candidate for cryptographic standards in the post-quantum era because of its advantages such as quantum-immune, the reduction of the worst-case to average-case, and so on. Therefore, this paper focuses on the detailed analysis and efficiency comparison of existing lattice-based threshold ring signatures and lattice-based linkable ring signatures. The inherent anonymity of ring signatures makes them have unique advantages in the era of industrial blockchain, so this paper elaborates on several applications of ring signatures in blockchain. For example, the application of ring signature in anonymous voting, medical data sharing, and Internet of vehicles is summarized and analyzed. The application significance of ring signature in the fields of virtual currency, SIP cloud call protocol, and Ad Hoc network is briefly sorted out. Finally, the research of ring signature technology in recent years is analyzed, and the current problems are summarized.

Key words: lattice, threshold ring signature, linkable ring signature, anonymity

摘要： 环签名作为一种特殊的群签名，因其不仅可以在不需要环成员协作的情况下完成签名，还能保证签名者的匿名性这一特点，已被广泛应用在匿名投票、匿名存证以及匿名交易等领域。首先，以时间为主线，将环签名发展分为不同的阶段，在每个阶段内又根据属性将环签名分为门限环签名、可链接环签名、可撤销匿名性的环签名、可否认的环签名等签名方案。通过对环签名发展历程的分析可知，环签名在门限环签名和可链接环签名领域的研究进展较为突出，其应用领域也最为广泛。在后量子时代，诸如基于大整数分解、离散对数等传统数论问题的密码方案已经不再安全，格公钥密码体制因其抗量子性、存在最坏实例到普通实例的规约等诸多优势成为后量子时代密码标准的最佳候选。因此，着重对现有基于格的门限环签名和基于格的可链接环签名进行了详尽的分析和效率比对。环签名天然的匿名特性使得其在产业区块链时代有着得天独厚的优势，因此将环签名在区块链中的几个应用进行了详细阐述。诸如对环签名在匿名投票、医疗数据共享、车联网领域的应用进行了概述和流程分析；又对环签名在虚拟货币、SIP云呼叫协议、Ad Hoc网络领域的应用意义进行了简单梳理。最后，对环签名技术近几年的研究进行分析，并总结了目前存在的问题。

关键词: 格, 门限环签名, 可链接环签名, 匿名性

XIE Jia, LIU Shizhao, WANG Lu, GAO Juntao, WANG Baocang. Research Progress and Prospect of Ring Signatures[J]. Journal of Frontiers of Computer Science and Technology, 2023, 17(5): 985-1001.

谢佳, 刘仕钊, 王露, 高军涛, 王保仓. 环签名技术研究进展及展望[J]. 计算机科学与探索, 2023, 17(5): 985-1001.

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