The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 11, 2012
Filed:
Jun. 30, 2008
Olivier Billet, Tourrettes sur Loup, FR;
Yannick Seurin, Saulx les Chartreux, FR;
Jacques Patarin, Versailles, FR;
Olivier Billet, Tourrettes sur Loup, FR;
Yannick Seurin, Saulx les Chartreux, FR;
Jacques Patarin, Versailles, FR;
France Telecom, Paris, FR;
Abstract
The invention proposes a method and a device for decrypting an encrypted message represented by a sequence C or applying an electronic signature to a sequence C, said sequence C consisting of data belonging to a finite field K=GF(q), where q>1, in which there are processed successive blocks each comprising (n·d) successive data items from the sequence C, where n and d are predetermined integers greater than 1, the processing of such a block including the following steps: applying a predetermined affine invertible transformation tto said block; interpreting the resulting block as being formed of n successive elements (y, y, . . . , y) of an extension E=GF(q) of the field K; calculating an n-tuplet (x, x, . . . , x) of elements of the field E by solving a system f of n predetermined polynomials of the form in which the coefficients a, b, and cbelong to E and the exponents α, β, and γare positive or zero integers; interpreting said n-tuplet (x, x, . . . , x)as being a new block formed of (n·d) successive elements from the field K; and applying a predetermined affine invertible transformation sto said new block.