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:
May. 06, 2014
Filed:
Jun. 15, 2010
Thomas Icart, Paris, FR;
Jean-sebastien Coron, Asnieres, FR;
Thomas Icart, Paris, FR;
Jean-Sebastien Coron, Asnieres, FR;
Morpho, Paris, FR;
Abstract
A cryptographic calculation includes obtaining a point P(X,Y) from a parameter t on an elliptical curve Y=f(X); and from polynomials X(t), X(t), X(t) and U(t) satisfying: f(X(t))·f(X(t))·f(X(t))=U(t)in Fq, with q=3 mod 4. Firstly a value of the parameter t is obtained. Next, the point P is determined by: (i) calculating X=X(t), X=X(t), X=X(t) and U=U(t); (ii) if the term f(X)·f(X) is a square, then testing whether the term f(X) is a square in Fand if so calculating the square root of f(X) in order to obtain the point P(X); (iii) otherwise, testing whether the term f(X) is a square and, if so, calculating the square root of f(X) in order to obtain the point P(X); (iv) otherwise, calculating the square root of f(X) in order to obtain the point P(X). This point P is useful in a cryptographic application.