| 摘要 |
The invention relates to a cryptographic method wherein a random number generator producing random numbers S<SUB>i </SUB>whose size N is fixed between 0 and W-1 is used to produce a random number R between 0 and a predefined limiter K. According to the invention: E 31 : a random variable Si is produced, ranging from 0-W-1, E 32 : if the random variable S<SUB>i </SUB>is strictly lower than a coefficient K<SUB>i </SUB>of the limiter K in base W, the coefficient R<SUB>i </SUB>of order i of the random number R is equal to the random number S<SUB>i </SUB>then, for all orders j which are lower than i, a random variable S<SUB>j </SUB>of 0-W-1 is produced and R<SUB>j</SUB>=S<SUB>j</SUB>. E 33 : unless, if said random variable is greater than coefficient K<SUB>i </SUB>of position i of the limiter K is base W, whereupon said coefficient R<SUB>i </SUB>is determined on the basis of the random variable Si of order i according to a predetermined function, then a coefficient R<SUB>i-1 </SUB>is determined for the random number R of order i-1 which is immediately lower by repeating stages E 31 -E 33 . The invention also relates to an electronic component which is adapted for implementation of said method and a chip card with said component integrated therein. The invention can be applied to cryptographic calculation.
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