欧拉函数算法实现及其应用

介绍了欧拉函数的3种算法和5个推论,论述了欧拉函数在离散数学和网络安全(加密学)中的应用,并提出了欧拉函数的几个猜想。     

多秘密共享可视密码及在防止欺骗上的应用

本文将多秘密共享应用于可视密码,提出多秘密共享可视密码并将其实现,提出改进算法,证明其优越性,且对(2,n,n)多秘密共享可视密码进一步改进.最后指出两秘密共享可视密码可以非常好的应用于防止欺骗可视密码.     

RSA算法的内在特性、破解与防范措施

为了给RSA(Rivet、Shamir和Adelman提出的)算法的使用者提供参考,从不动点、周期性、对明文的要求、保密性和加密速度等方面分析了这种加密算法的内在特性,从理论和实际两方面对该算法的脆弱性以及针对该算法的攻击方法进行了分析。归纳出如何防范针对该算法攻击的结论,得出了RSA使用者使用的密钥匙位数必须大于2048位才能保证算法安全性这一结果．通过给黑客的攻击方法进行分类,从算法维护和安全策略定制的角度,总结了网络安全人员提升加密算法安全性的办法．     

Binary Sequences from a Pair of Elliptic Curves

A family of binary sequences were constructed by using an elliptic curve and its twisted curves over finite fields. It was shown that these sequences possess ＂good＂ cryptographie properties of 0-1 distribution, long period and large linear complexity. The results indicate that such se quences provide strong potential applications in cryptography.     

A Generic Solution to Realize Public Verifiability of Signcryption

0 IntroductionIn 1997 , Zheng[1]proposed a new pri mitive called sign-cryption, which si multaneously provides authenticity andconfidentiality within a single logic step.Signcryptionis moreefficient than the conventional“sign-then-encrypt”approach.Many signcryption schemes[2-5]have been proposed so far .For more details about the development of signcryption we re-fer the readers to Ref .[6] .Asecure signcryptionscheme should satisfy public verifi-ability (including non-repudiation)[1]. Wef…     

An Efficient and Secure Multi-Secret Sharing Scheme with General Access Structures

A multiple secret sharing scheme can share a group of secrets in each sharing session, which is very useful especially in sharing large secrets. However, most of the existing multiple secret sharing schemes are （t, n） threshold schemes, so they are fit for only threshold applications and unfit for the applications of general access structures. Due to the fact that a （t, n） threshold scheme could only handle a small fraction of the secret sharing idea, a novel multi-secret sharing scheme is proposed, which is designed based on general access structures. The security of this scheme is the same as that of Shamir＇s threshold secret sharing scheme. Compared with the existing multiple secret sharing schemes, the proposed scheme can provide greater capabilities for many applications because it is able to deal with applications of general access structures.     

Multi secret image color visual cryptography schemes for general access structures

In the proposed visual cryptography schemes for general access structures, the single secret image black-and-white visual cryptography schemes with meaningful shares have been constructed, in which the shares are innocent looking images. The meaningful shares have not been realized in single secret image color schemes; neither have the multi secret images color schemes. In this paper, the multi secret images color visual cryptography schemes for general access structures with meaningful shares are constructed by the method of matrix concatenation, the pixel expansion is obtained, and the validity of the scheme is proven. In our scheme, the different combination of meaningful color shares can be used to recover distinct color secret images. The multi secret images black-and-white visual cryptography scheme is a special case of our color scheme.     

The New Enhanced Simple Authenticated Key Agreement Algorithm

IntroductionDiffie-Hell man key agreement[1]is a well-knownmethod by which two authenticated parties may use aninsecure channel to agree a session key for use withconventional symmetric encryption algorithm. However ,itis vulnerable to the man-in-the-middle attack. Adoptingcertificates (e .g . digital signature) into a key exchangeprotocol can foil man-in-the-middle attack,but its extensionto a larger system may be difficult for the key exchange withcertificates requiring some more trusted aut…     

一种指定接收者椭圆曲线门限群签名加密方案

提出了一种指定接收者椭圆曲线门限群签名加密方案.该方案根据Nyberg和Rueppel方法,利用椭圆曲线加密技术将门限群签名与指定接收者公钥加密有机地结合在一起,构造一种指定接收者的门限签名群加密方案.与传统的消息加密再数字签名的方法相比,该方案具有数据传输安全、计算复杂度和通讯复杂度低、通讯带宽小等优点.     

基于PKI的电子商务安全密钥托管方案

从保护用户托管私钥安全与防止用户逃避密钥托管的角度出发,研究了一种基于ＰＫＩ的电子商务密钥托管方案。提出了密钥托管的概念及其执行机构密钥托管代理（ＫＥＡ）,分析了密钥托管系统的结构框架及其组成部分,指出电子商务数字证书应与密钥托管相互关联。提出了一种基于离散对数安全密钥托管方案,并给出了通信双方的操作过程以及政府职能部门在密钥托管机构的帮助下强制访问的步骤。