P-Box
- P-Box
-
P-Box (permutation box), terme anglais désignant une table de permutation employée dans des algorithmes de chiffrement. Elle indique comment échanger les éléments d'une structure. Une P-Box contribue à la « diffusion » (terme employé par Claude Shannon) en mélangeant les données et en améliorant l'effet avalanche.
Une P-Box peut se présenter sous plusieurs formes mais algorithmiquement, il s'agit en général d'un tableau à une dimension comme [1,8,5,3,4,6,7,2]. Ce tableau signifie que le premier élément reste en place, que la deuxième sortie prend la valeur de la huitième entrée, que la troisième sortie prend la valeur de la cinquième, etc.
Voir aussi
Wikimedia Foundation.
2010.
Contenu soumis à la licence CC-BY-SA. Source : Article P-Box de Wikipédia en français (auteurs)
Regardez d'autres dictionnaires:
Box — describes a variety of containers and receptacles. When no specific shape is described, a typical rectangular box may be expected. Nevertheless, a box may have a horizontal cross section that is square, elongated, round or oval; sloped or domed… … Wikipedia
Box (Wiltshire) — Box ist ein englisches Dorf in der Grafschaft Wiltshire. Es liegt etwa 8 km östlich von Bath und 11 km westlich von Chippenham. Durch weit auseinander liegende Ortsteile bedeckt das Dorf eine große Fläche. Die Gegend ist reich an Natursteinen und … Deutsch Wikipedia
Box — Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material and… … The Collaborative International Dictionary of English
Box beam — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box car — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box chronometer — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box coat — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box coupling — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box crab — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box drain — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
Box girder — Box Box, n.; pl. {Boxes} [As. box a small case or vessel with a cover; akin to OHG. buhsa box, G. b[ u]chse; fr. L. buxus boxwood, anything made of boxwood. See {Pyx}, and cf. {Box} a tree, {Bushel}.] 1. A receptacle or case of any firm material… … The Collaborative International Dictionary of English
