基于组件技术的密码学理论与技术实验教学方法

文章对目前信息安全专业课程体系中密码学理论与技术实验教学中存在的问题进行了分析,探讨了利用基于组件技术的虚拟实验室进行密码学实验教学的一些想法,并提出了改进的教学方法.通过两种实验教学方法的效果比较,证明了采用组件技术的虚拟实验教学模式对于提高教学质量、改进教学效果提供了一种先进的实验教学模式.     

The grand lines of cryptology's development

Cryptology has developed along three major lines. Technologically, its operations have grown increasingly complex as science has provided new ways of realizing them. Economically, its use has expanded as society has required it more and more while its cost has dropped. Philosophically, it has moved from a sacred to a secular mode of use and then continued this trend to greater rationalization by increasingly using mathematics.     

Performance study of Byzantine Agreement Protocol with artificial neural network

Since 1982, numerous Byzantine Agreement Protocols (BAPs) have been developed to solve arbitrary faults in the Byzantine Generals Problem (BGP). A novel BAP, using an artificial neural network (ANN), was proposed by Wang and Kao. It requires message exchange rounds similar to the traditional BAP and its suitability, in the context of network size, has not been investigated. In the present study, we propose to adopt Nguyen-Widrow initialization in ANN training, which modifies message communication and limits the message exchange rounds to three rounds. This modified approach is referred to as BAP-ANN. The BAP-ANN performs better than the traditional BAP, when the network size n is greater than nine. We also evaluate the message exchange matrix (MEM) constructed during the message exchange stage. For a fixed number of faulty nodes and remainder cases of (n mod 3), the study shows that the mean epoch for ANN training decreases as the network size increases, which indicates better fault tolerance.     

用BCH等线性分组码构造McEliece纠错码公钥密码体制

McEliece公钥密码体制是用线性纠错码中的一种特殊码类Goppa码构造的。本文则表明采用BCH码或RS码等线性分组码也可构造安全的McEliece公钥密码体制。     

SHA-1充分条件自动化求解算法

充分条件的求解是模差分攻击的重要步骤之一。将充分条件的求解转化为F₂上线性方程组的构造过程,利用线性方程组解的判定定理判断每步所求得充分条件的正确性,提出了针对SHA-1模差分攻击的充分条件自动化求解算法。文中算法做适当变形后,同样适用于MD5、SHA-0等与SHA-1结构相似的Hash函数充分条件的自动化求解。     

密码协议中"现时"的产生与管理

根据密码协议中会话的新鲜性要求、基于Needham-Schroeder认证协议的对称密钥版本和非对称密钥版本，给出了两个“现时”(nonce)产生方案及相应的管理机制。     

浅析加密算法及应用

提出了加密数据的通信过程,并分析了两个加密算法,同时给出了算法的代码.     

单双钥混合体制的选择密文安全性

该文主要讨论单双钥混合体制的选择密文安全性IND-CCA的定义和相关结论。在对两种不同用途的单双钥混合体制及其安全性的研究之后发现它们的IND-CCA定义中允许敌手访问的预言机不同,我们将其统一为:对只能询问混合体制整体解密机的敌手的安全性,从而统一了混合体制的安全结论,为正确使用混合体制提供了依据。我们提出了一种混合体制:REACT+,并证明了其IND-CCA安全性。     

NAVAL SECURITY GROUP COMMAND DISPLAY

Presented here is information concerning the move of the U. S. Navy's Wenger Cryptologic Museum from 3801 Nebraska Avenue NW, Washington DC, to Corry Station, Pensacola FL. The move was required when the Naval Security Group moved to Fort Meade, Maryland several years ago. The move has been completed and the new facility is now open to the public. It has a new name; it is now called the Naval Security Group Command Display.     

A MESSAGE IN CIPHER WRITTEN BY GENERAL CORNWALLIS DURING THE REVOLUTIONARY WAR

We present an annotated list of a few cryptologic rewards that can be found in “cyberspace.”