Patent ID: 7286666
Filing Date: 2007-10-23
Classification: G06F,H04L

Abstract:
1. A countermeasure method in an electronic component implementing a public key cryptography algorithm based on the use of elliptical curves in which a deciphering integer d′ is calculated, using a private key d and a number of points n on an elliptical curve, such that the deciphering of any enciphered message, by means of a deciphering algorithm, with d′, gives the same result as with d, by effecting the operation Q=d*P, where P is a point on the curve, said method including the following steps: 1) determining a security parameter s; 2) drawing a random number k between 0 and 2 3) calculating the integer d′=d+k*n; and 4) calculating Q=d′*P.