DES加密算法的研究与实现毕业论文.docVIP

摘 要 随着信息技术的发展，计算机应用渗透到社会生活的各个领域，人们对信息化的依赖程度越来越高，随之而来的安全性问题成为人们关注的热点。数据加密技术作为信息安全中的重要武器，发挥着越来越大的作用。DES (Date Encryption Standard)算法从成为加密标准到现在，已经成功在应用在了很多领域并且经历了长期的考验。实践证明，DES算法对于大部分的应用来说，还是足够安全的。 本论文首先介绍语言及其实用软件，然后介绍DES加密算法原理；接着介绍DES加密模块的三大底层模块的原理与设计；最后介绍了顶层模块的调用与设计，测试文件的编写，从整体上完成了对DES加密模块的实现。 本文通过语言来实现DES加密模块的设计与。本设计采用自顶而下的模块化设计方法将DES加密模块划分为四大模块，其中包括三个底层模块 ：密钥产生模块、S部件代换模块（S1、S2、S3、S4、S5、S6、S7、S8）、DES的一轮变换模块，还含有一个顶层调用模块，整体的调用三个底层模块用来实现DES加密模块的功能。 关键词：DES加密；Abstract With the development of information technology, the application of computer has came into any field. People’s dependence on information technology is becoming more. Followed by the issue of security has also become a hot spot of concern to the people . Encryption technology, as an important weapon of information security, is playing an increasingly important role. DES (Date Encryption Standard) encryption algorithm from becoming the standard to the present , has been successfully used in a lot in the area and has experienced long-term test. Practice has proved that, DES algorithm for most of the application adequate is security. This paper introduces C language and its utility software Visual C++6.0, and introduces the DES algorithm, and then introduces the DES encryption module the three underlying modules principles and design. Finally, it introduces the top-level module and its design as well as the test documentation, and achieves the whole DES encryption module Through the C language , this paper achieves DES encryption module design and simulation. The design uses a top-down modular design method to DES encryption module, it is divided into 4 modules，which contains three bottom modules: key generation module, S module and one transformation module of DES, and it also contains a top-level module which calls the bottom of the overall three modules for the function of DES encryption module. In addition , the security of DES evaluation and briefly proved three DES encryptio