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Breaking an SPN Cipher where the permutation is just the identity permutation

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I've had this problem that I've been trying to figure out for a while. Can a SPN cipher be broken by a chosen-plain text attack if the permutation for the SPN is just the identity permutation? For example would we be able to do this if the block length is 128, and the key length is also 128, the number of rounds is 16. I had some ideas of how to approach this but I'm not sure, would we be able to figure out the secret key using a chosen-plaintext attack or can we just systematically find the plaintext from a given cipher text?

kelalaka avatar
in flag
Welcome to [cryptography.se] Draw the SPN network with identity permutation, what do you see? This is actually the reason one tells that we need a good permutation. Do they not teach in this way? What do they teach with SPN?
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