I'm a beginner in the complex world of cryptography. Doing some basic course on DES, and I found a peculiar (to me) pattern within DES' Initial Permutation table.

The table is built as an 8x8 matrix with shift position: https://en.wikipedia.org/wiki/DES_supplementary_material#Initial_permutation_.28IP.29

The pattern graphically presented on the wiki page happens to decrease by 8 in every row. What's also interesting, is that the values between neighbouring rows, but different columns seem to differ by 2.

This may be "just randomly selected", but assuming that DES has been thoroughly designed, implemented and - most importantly - tested, this seems on purpose. Hence: What is the significance of the pattern within IP?

(my wild guess is that it's of rather little importance, as IP is easily reversible)


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