基于椭圆曲线和RSA的数字签名的性能分析

数字签名是电子商务、电子政务开展的有力保障。他在实现身份验证、数据完整性、不可抵赖性等功能方面都有重要应用。其实现基础是加密算法技术,使用公钥加密算法和散列函数。目前主要的数字签名算法有RSA,ELGamal和椭圆曲线密码(ECC)。介绍了基于ECC和RSA数字签名算法的一般模型,并且给出了两种签名算法在C 下的性能比较,根据比较结果分析,探讨两种数字签名算法的应用范围。     

Elliptic Curve Paillier Schemes

This paper is concerned with generalisations of Paillier's probabilistic encryption scheme from the integers modulo a square to elliptic curves over rings. Paillier himself described two public key encryption schemes based on anomalous elliptic curves over rings. It is argued that these schemes are not secure. A more natural generalisation of Paillier's scheme to elliptic curves is given. Received January 2001 and revised June 2001 Online publication 23 November 2001     

有理区间的安全多方计算与应用

本文研究了有理数与有理区间的位置关系以及两个有理区间位置关系的安全多方计算.它们已广泛应用于数据库匹配、定位搜索等领域,是保密科学计算的一个重要分支.但目前已有文献在解决有理数与有理区间的位置关系时提出的协议效率较低,且两个有理区间位置关系问题的研究较为有限.针对这些问题,本文首先用多项式表示区间,将有理数与有理区间位置关系问题转化为整数向量的内积符号判定问题,设计了新的有理数与有理区间的保密计算协议.其次,以有理数与有理区间协议作为基础模块,设计了两个有理区间位置关系的保密计算协议.最后,理论分析及实验结果均表明本文方案是安全高效的,并给出了本文协议在有理数域上的百万富翁问题及计算几何问题的应用.     

Secret key rates of free‐space optical continuous‐variable quantum key distribution

In this letter, we derive the maximal achievable secret key rates for continuous‐variable quantum key distribution (CVQKD) over free‐space optical (FSO) quantum channels. We provide a channel decomposition for FSO‐CVQKD quantum channels and study the SNR (signal‐to‐noise ratio) characteristics. The analytical derivations focus particularly on the low‐SNR scenarios. The results are convenient for wireless quantum key distribution and for the quantum Internet.     

基于身份加密机制的光学加密密钥系统

从非对称的基于身份密钥体系出发,提出了一种适用于光学加密系统密钥管理的方法.首先简要介绍了基于身份密钥体系,特别是Boneh-Franklin算法,然后针对光学加密参数安全传输问题,给出了非对称密钥系统的密钥生成、分配、更新等算法,并从方法的复杂性、安全性等方面对算法进行了分析,最后对二维码加密问题进行了仿真,结果表明算法是正确有效和安全的     

集成加密方案ECIES的设计与验证

椭圆曲线密码（ECC,elliptic curve cryptograph）是密码学的重要分支之一,它可以用来加密数据,进行数字签名或者在安全通信的开始阶段进行密钥交换。在加密方面,基于ECC最有名的就是综合加密方案（ECIES,elliptic curve integrate encrypt scheme）。ECIES是Certi-com公司提出的公钥加密方案,可以抵挡选择明文攻击和选择密文攻击。ECIES各个步骤的实现可以用不同的算法,在软件中是可以配置的。而它实现的多样性也验证了它的灵活性以及可靠性。     

An ECC‐based authenticated group key exchange protocol in IBE framework

With the rapid demand for various increasing applications, the internet users require a common secret key to communicate among a group. The traditional key exchange protocols involve a trusted key generation center for generation and distribution of the group key among the various group members. Therefore, the establishment of a trusted key generation center server and the generation (and distribution) of common session key require an extra overhead. To avoid this difficulty, a number of group key exchange protocols have been proposed in the literature. However, these protocols are vulnerable to many attacks and have a high computational and communication cost. In this paper, we present an elliptic curve cryptography–based authenticated group key exchange (ECC‐AGKE) protocol, which provides better security and has lower computational cost compared to related proposed schemes. Further, a complexity reduction method is deployed to reduce the overall complexity of the proposed elliptic curve cryptography–based authenticated group key exchange protocol. The security of proposed work is ensured by the properties of elliptic curves. A security adversarial model is given and an extensive formal security analysis against our claim is done in the random oracle model. We also made a comparison of our proposed protocol with similar works and found that ours have better complexity, security and efficiency over others.     

Constructions of general (k,n) reversible AMBTC-based visual cryptography with two decryption options

In this paper, a general method of $(k\text{,}n)$ threshold Reversible Absolute moment block truncation coding Visual Cryptography Scheme (RAVCS) is introduced for sharing a binary secret image into multiple absolute moment block truncation coding (AMBTC) shadows. A $(k\text{,}k)$ RAVCS is firstly proposed to encode a secret by referencing one ABMTC image. Then, the proposed $(k\text{,}k)$ RAVCS is adopted to share the same secret into multiple groups of shadows by referencing multiple images. Those multiple groups of shadows are distributed to participants according to a matrix generated by the proposed shadow distribution algorithms. When any k or more participants share their shadows, the secret image is revealed by OR or XOR decryption. Further, those AMBTC shadows can be losslessly reverted to their original forms. Sufficient theoretical analysis and extensive experimental results are provided in this paper, showing the effectiveness and advantages of the proposed method.     

区间关系保密计算若干问题研究

安全多方计算是密码学界的一个重要研究方向,本文主要研究区间的安全计算问题.首先应用Paillier加密方案设计"点与区间"以及"区间与区间"关系两方保密计算基础协议,协议的特点是判定结果以密文形式输出.将其推广为有理区间关系判定协议时,相比已有协议,本文协议更为安全与高效.在此基础上,进一步研究多维度的"点与区间"以及...     

Certificateless generalized signcryption scheme in the standard model

In 2010,Liu,et al.proposed a certificateless signcryption scheme in the standard model,but many analyses revealed that Liu's scheme was insecure in fact.To overcome the disadvantages,the scheme was improved and a certificateless generalized signcryption scheme was constructed.In addition,a formal security model for the proposed scheme against the malicious-but-passive KGC attacks was introduced.Furthermore,the proposed scheme was proven to be secure under the decisional bilinear Diffie-Hellman and the computational Diffie-Hellman intractability assumptions in the standard model.Numerical results illustrate that the proposed algorithm is efficient.