【作者】 范昊；

【导师】 肖德宝；

【作者基本信息】 华中师范大学 ， 计算机应用技术， 2002， 硕士

【摘要】 计算机网络技术的发展，极大地推动了社会信息化进程，人们可以通过Internet很方便地进行信息交流。但是，公开便利的网络环境同时也带来网络通信安全方面的挑战。 在开放的网络环境中，公开密钥算法已成为网上电子商务和其他需要保密和验证的网络应用之基础。而广泛地公钥算法则又需要一个公钥基础结构(PKI)来公布和管理众多公开密钥。如果没有这样的一种基础结构，公钥加密的应用前景恐怕不会比传统的私钥加密宽广。 本文首先在综述Internet加密算法与安全机制的基础上，分析了适合于一般PKI系统的PKI基本特征。运用这些特征，文章对几种常用的PKI构想进行了讨论，着重对他们的结构及存在的问题作了详细的分析，并简要对问题的解决方法与系统的具体实现进行了介绍。 其次，文章在第五章分析了一般C／S模式中存在的安全性隐患，提出用密文形式传输和存储用户口令的方法，解决用户口令在传送和存储时有可能被窃听或截取的问题。同时，在结合PKI模式中CA认证、数字签名以及公开密钥与对称密钥算法技术的基础之上，提出了密文传输和存储口令机制下的用户注册和C／S、B／S模式资源访问的基本模型，以实现C／S和B／S的安全机制。 文章最后运用Java语言，实现了客户端的数字签名与加密机制和服务器端的信息解密与数据完整性验证。整个系统以演示为目的，将各种功能明显地加以区分，分步实现各阶段的功能，旨在说明数字签名与数据完整性验证的详细过程。更多还原

【Abstract】 The developments of computer network technology are powerfully improving the process of the society information. Now it is very conveniently that people can exchange message with each other on the Internet. At the same time, however, the opened and well-suited network can bring the challenge of security of the network communication.Public-key cryptography is fast becoming the foundation for online commerce and other applications that require security and authentication in an opened network environment. The widespread use of public-key cryptography also requires a public-key infrastructure (PKI) to publish and manage public-key values. Without a functioning infrastructure, public-key cryptography is only marginally more useful than traditional, secret-key cryptography.This thesis reviews the basic of the encryption algorithm and security framework, analyses a set of PKI characteristics that apply to any PKI system, And uses these characteristics to describe several internet PKI proposals in common use. This thesis emphasizes to analyse their structure and matters, then describes the resolvent and action method of all kinds of system.In chapter 5, the thesis analyses the hidden trouble of security hi usually C/S pattern, advances a measure of transferring and memorizing the user’s password in cryptograph form to solve the trouble that user’s password can be eavesdropped and intercepted possibility when it was transferred and memorized. Contemporary, with the basic of CA Authentication, Digital Signature, Public-key cryptography and Secret-key cryptography, this thesis bring forward a basic model of user registration and C/S, B/S resource accessing under the mechanism that using cryptography to transfer and memory the user’s password.At last, using Java language, the thesis implements Client’s Digital Signature & Encryption and Server’s Decryption & Integrality Validation. The system is a demo program, and distinguishes all kinds of functions very obviously. It implements each phase function step by step, in order to explain the particular process of Digital Signature and Integrality Validation.更多还原