Talk:Permutation box

Confusion (pun intended)
I think this needs some documentation that the terminology of "P-box" is real and widely accepted. I'm a cryptographer, and I've never heard of this term. The entry cites reference [1], but reference [1] doesn't exist. I suspect this is a personal nomenclature that is not widely used, or something made up, or a typo for S-box. Also, the entry seems to have factual errors or confusions. It claims that it "retains diffusion" (whatever that means), but a permutation (re-ordering) of the bits cannot provide any diffusion. Overall, I think this entry should be deleted. — Preceding unsigned comment added by 128.32.153.194 (talk) 20:10, 7 January 2013 (UTC)
 * Bruce Schneier's Applied Cryptography uses the term in its discussion of DES and related Feistel ciphers. A little googling around convinces me that lots of others use it in this context as well. Ntsimp (talk) 23:29, 7 January 2013 (UTC)

Illustration caption: straight or expansion permutation?
The current caption of the sole illustration in the article starts with the words ”an example of a 64-bit "expansion" P-box”. Isn’t it, in fact, a textbook representation of a straight permutation? It sure looks bijective to me (and the array in the image description confirms it). — Wlgrin 00:10, 12 January 2022 (UTC)

Meaning of "permutation"
See the discussion at Talk:Substitution–permutation network. Dimawik (talk) 22:39, 9 October 2023 (UTC)