Cryptography/Basic Design Principles

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Good cyphers often attempt to have the following traits.

[edit] Diffusion

Having good diffusion means that making a small change in the plain text should ideally cause as much as possible of cipher text to have a fifty percent possibility of change.

For example a Caesar cipher has almost no diffusion while a block cypher may contain lots of it.

[edit] Confusion

For good confusion the relationship between the cypher text and the plain text should be as complex as possible.