[密码学基础][每个信息安全博士生应该知道的52件事][Bristol Cryptography][第9篇]香农对熵和信息的定义是什么?

淡淡的烟草味﹌ 2023-02-27 10:34 8阅读 0赞

这是计算机理论的最后一篇.我们讨论信息理论的基础概念,什么是香农定义的熵和信息.

![在这里插入图片描述][20200716224358689.png]

## 熵 ##

熵与确定性成反比  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RhZG9uZ3d1ZGk_size_16_color_FFFFFF_t_70]

## 信息 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RhZG9uZ3d1ZGk_size_16_color_FFFFFF_t_70 1]

## 密码学实例 ##

![在这里插入图片描述][20200716225006420.png]  
\[1\] Thomas M. Cover and Joy A. Thomas. Elements of Information Theory  
 2nd Edition. Wiley-Interscience, 2 edition, July 2006.

\[2\] S. Vajda, Claude E. Shannon, and Warren Weaver. The mathematical  
 theory of communication. The Mathematical Gazette, 34(310):312+,  
 December 1950.

\[3\] http://en.wikipedia.org/wiki/Entropy\_(information\_theory)  
原文链接：https://www.cnblogs.com/zhuowangy2k/p/11892615.html  
转载链接：http://bristolcrypto.blogspot.com/2014/12/52-things-number-9-what-are-shannons\_7.html

[20200716224358689.png]: /images/20230209/92b79149ea7a4a7899f1db16a65b38b6.png
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[20200716225006420.png]: https://img-blog.csdnimg.cn/20200716225006420.png