公钥密码安全强度刻画概述

Survey on Public Key Cryptography Security Strength

安全强度是对密码方案安全性的量化指标,代表了攻破某密码方案所需的计算开销.公钥密码方案的安全强度与构建该方案所依赖的困难问题和具体的参数有关.随着后量子密码学的发展,原先单一的安全强度评估标准产生了变化和扩充.因此,系统性总结数论体系下的经典公钥密码和抗量子攻击的后量子公钥密码的安全强度具有重要意义.本文首先介绍了经典公钥密码和后量子公钥密码的安全强度定义.然后给出了一些经典公钥密码方案的安全强度和后量子公钥密码方案的安全强度级别.接着从常见密码方案的现实应用出发,介绍若干在商用安全服务中使用的公钥密码方案及其安全强度分析.最后,给出本文的总结,并根据目前公钥密码安全性研究和应用的不足,对未来的研究和应用提出了展望.

Security strength is a quantitative indicator of a cryptography scheme’s security,representing the computational cost required to break the scheme.The security strength of a public key cryptography scheme corresponds to the hard problem that it is based on and the selection of scheme parameters.With the development and enrichment of the post-quantum cryptography,the original security strength evaluation standard has been changed and expanded.In order to summarize the security strength of classical public key cryptography based on number theory problems and post-quantum public key cryptography based on mathematical hard problems which are difficult to solve even for quantum computers,this paper first introduces the definition of security strength of classical and post-quantum public key cryptography,then introduces the security strength of some typical classical and post-quantum public key schemes.After that,the security strength analysis of the public key schemes implemented in commercial security services is proposed.Finally,according to the shortcomings of the current research and application of public key cryptography,some future research directions are put forward,and the conclusion of this paper is given.