摘 要
信息技术的飞速发展，使人们的生活面貌发生了很大改变，同时信息技术也促进了社会的发展。在计算机网络深入普及的信息时代，信息本身就是时间，就是财富。如何保护信息的安全使之不被窃取及不至于被篡改或破坏，已成为当今普遍关注的重大问题。密码是有效且可行的办法。
本文主要介绍DES加密与解密算法的C++语言实现，从密钥生成、DES加密原理、DES解密原理3方面阐述了DES算法的整个过程。并在此基础上，在windows环境下，利用标准VC++6.0实现DES加密与解密算法，以窗体界面方式完成1个本地的文件加解密演示器。
关键词：信息安全；密钥； DES；加密；解密；VC++6.0
Abstract
The information technology rapid development, caused peoples life appearance to have the very big change, simultaneously the information technology also promoted societys development. In the computer network thorough popularization information time, information itself is the time, is the wealth. How protects the information the security to cause it not to steal and as for not to tamper with or the destruction, has become the major issue which now generally pays attention. The password is the extremely useful one kind of labor
This article mainly introduces the DES encryption and the decipher algorithm C language realization, Decipher principle three aspects elaborated from key fresh room DES、 the encryption principle DES、 the DES algorithm entire has worked. And in this foundation, In windows environment, realizes the DES encryption and the decipher using standard VC++6.0 calculates, Completes a local document by the window contact surface way to add the decipher demonstration.
The present paper altogether spanides into seven to blow, First chapter promulgates the cryptology from the modern electronic technology development to be important in the scientific domain, Thus explained chooses this topic to take the graduation project originally. Second chapter narrated the cryptology elementary knowledge, Third is this article key point, Take narrates the DES history as the beginning, A explanation DES algorithm original hollow piece of jade, Meanwhile how to make the encrypts key、 encrypts the DES decipher take key、 fresh room DES as the line, Realizes the DES encryption and the decipher code using the C++ language supposes discusses. Fourth chapter makes the simple introduction to the window contact surface, Explane how the ming dynasty printed books demonstration should use. Fifth chapter carries on the analysis to the DES existence security simultaneously to separate out the feasible solution, Sixth chapter carries on the brief introduction to the DES working pattern, Introduced with emphasis this article adopts ECB pattern. Seventh chapter gives an example to carry on the test to the code, Confirms whether conforms to the standard DES encryption to reconcile Laos.
KeyWords：Information security; Key; DES; Encryption; Decipher; VC++6.0.
