# How to prove a cipher resistant to differential cryptanalysis?

How do you prove that a cipher is resistant to differential cryptanalysis? It's said that Rijndael has been proven resistance to differential cryptanalysis. How do cryptographers do that?

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possible duplicate of How do I apply differential cryptanalysis to a block cipher? – rath Jul 14 '13 at 23:41
Why is this a duplicate? The other is a question about how to apply differential cryptanalysis, and this question is about proving a function resistant to differential cryptanalysis. – Gavriel Feria Jul 16 '13 at 0:26
the keyword being 'possible' duplicate. – rath Jul 16 '13 at 1:28
rath, you can add possible to any sentence and you can make it valid. So I think you are being a big harsh here. – tony9099 Mar 30 '15 at 16:40