混淆与扩散的区别

混淆和扩散区域统一了创建安全密码的属性。每个混淆和扩散区域单元都不会阻止其推导或最终阻止第一个消息的秘密写入密钥。

混淆用于制作不知情的密文，而扩散用于增加明文在密文最重要的部分上的冗余以使其模糊。流密码仅依赖于混淆，否则，每个流密码和分组密码都采用扩散。

Confusion = Substitution
a --> b
Caesar Cipher 


Diffusion = Transposition or Permutation
abcd --> dacb
          DES 

让我们看看黑白混淆和扩散的区别：

S.NO	Confusion	Diffusion
1.	Confusion is a cryptographic technique which is used to create faint cipher texts.	While diffusion is used to create cryptic plain texts.
2.	This technique is possible through substitution algorithm.	While it is possible through transportation algorithm.
3.	In confusion, if one bit within the secret’s modified, most or all bits within the cipher text also will be modified.	While in diffusion, if one image within the plain text is modified, many or all image within the cipher text also will be modified
4.	In confusion, vagueness is increased in resultant.	While in diffusion, redundancy is increased in resultant.
5.	Both stream cipher and block cipher uses confusion.	Only block cipher uses diffusion.
6.	The relation between the cipher text and the key is masked by confusion.	While The relation between the cipher text and the plain text is masked by diffusion.