【作者】 孙文静；

【导师】 傅德胜；

【作者基本信息】 南京气象学院 ， 系统分析与集成， 2003， 硕士

【摘要】 随着计算机通信技术与Internet的飞速发展，用户对信息的安全存储、安全处理和安全传输的需求越来越迫切。本文针对当前密码学的自身特点，结合密码学的最新发展方向，对网络数据加密进行了研究。 本文首先介绍了当前网络安全采用的一系列对策与技术，然后着重研究了包括私钥加密、公钥加密、数字签名、检验数据完整性等诸多网络数据加密技术。通过比较与分析，给出了私钥算法与公钥算法各自的优缺点。在此基础上，本文设计了网络通信数据加密系统，该系统将对称加密算法3DES与非对称加密算法RSA相结合对数据加密，用公钥算法RSA和单向散列函数MD5实现对文件的数字签名，有效地实现了网络通信系统中的信息加密、数字签名、身份认证等功能，保证了发送方所发送信息的秘密性、鉴别性、完整性及不可否认性。此外，本文还设计了一个功能强大的加密算法类库，对多种加密算法进行了封装，为其它应用程序的加密请求提供了接口。以此为平台，可有效方便地进行网络数据加密，这对提高数据加密的实时性有重要意义。类库中设计了九个类，使用该类库可完成3DES，MD5和RSA等加密解密运算。 最后对系统进行了算法实现，通过VC++开发了网络通信数据加密系统。 实验结果表明，该系统具有较强的稳定性、可靠性和适应性，已基本达到实用水平。更多还原

【Abstract】 With rapid development of computer communicating techniques and Internet, users are in more and more need of secure storage, secure transaction and secure transportation. Aiming for the characters of the current cryptology, this paper is combined with the latest developing direction of cryptology and carries on a study on data encryption for network communication.This paper introduces a series of countermeasures and techniques of current network security, and then studies on several data encrypting techniques for network emphasizly, e.g. private-key encryption, public-key encryption, digital signature, message integrity check. It gives out advantages and disadvantages of private-key algorithm and public-key algorithm through comparison and analysis. The paper designs a data encryption system for network communication, which combines the private-key algorithm 3DES with the public-key algorithm RSA to encrypt data and signs on files with public-key algorithm RSA and one-way hash function MD5. The system can actualize encryption of data, digital signature and identification efficiently and ensure privacy, authenticity, integrity and nonrepudiation of data. The paper designs an encrypting algorithm class library, which has powerful functions. The library envelops encryption algorithms and affords interfaces for the encrypting requests of other application programs. Data encryption for network communication can be brought into effect conveniently based on this class library, which makes important meaning for improving real time degrees of data encryption. 3DES, RSA and MD5 can be achieved by using nine classes defined in the class library.Finally the system is realized by algorithm and the data encryption system for network communication is developed in VC++ environment.The experimental result shows stability, liability and compatibility of the system which has reached utilitarian level.更多还原