Patent ID: 7567999

Claim:
A crypto processor for calculating a result or an integer multiple of the result of a division of a numerator by a denominator, comprising: a provision unit configured to provide a factor selected such that a product of the factor and the denominator is greater than the result; a modular reduction unit configured to modularly reduce a first product of the numerator and the factor using a modulus equaling a sum of a second product of the denominator and the factor and of an integer to obtain an auxiliary quantity comprising the result; a binary register for storing the auxiliary quantity comprising the result; and an extraction unit configured to extract the result or the integer multiple of the result from the auxiliary quantity stored in the binary register, wherein the result or the integer multiple of the result is calculated by the crypto processor in a cryptographic application, the numerator and the denominator being parameters in the cryptographic application, and wherein the result or the integer multiple of the result is used within the cryptographic application.