I'm trying to implement impossible differential cryptanalysis on IDEA cipher based on the Miss in the Middle Attacks on IDEA and Khufu, I've started by implementing the cryptanalysis on 3.5-Round IDEA and in order to achieve this cryptanalysis I need an initial pair set of $2^{32}$ pairs.

I've written all the code from scratch and I've stumbled with the fact that this pair set is talking forever to generate using my code.

So what I need to know is if $1$ million pairs is taking $2$ minutes to be encrypted , is the execution time considered good or it need to be faster?

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    $\begingroup$ No the pair concept is used in differential cryptanalysis when you have two plaintext that have a specific xor difference that is called input difference and we calculate the xor difference of their corresponding ciphertexts and call it the output difference and use these differences to attack the cipher @MaartenBodewes $\endgroup$
    – siba36
    Jun 20, 2022 at 6:53
  • $\begingroup$ Ah right, I somehow read "key pairs", which is of course not going to work. 2 minutes for 1 million pairs seems excessive, but in the end it very much depends on the processor, runtime, implementation and compiler optimization specifics. $\endgroup$
    – Maarten Bodewes
    Jun 20, 2022 at 20:23


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