Method of Performing a Modular Multiplication and Method of Performing a Euclidean Multiplication Using Numbers with 2N Bits

摘要

The invention relates to method of performing a modular multiplication using numbers with 2n bits. The method includes the steps of breaking the numbers (A, B) down into a 2ⁿ base or a U base, U being a suitable integer; and, subsequently, performing MultModDiv—and/or MultModDivlnit-type elementary operations on the numbers with n bits resulting from the first step. The invention also relates to a method of calculating a Euclidean multiplication/division. The invention can be used for cryptographic calculations.