| 摘要 |
<p>In a method for calculating the modular inverse R of a value E in relation to a module M, a breakdown of the module M into at least two factors M1, M2 is determined, a respective auxiliary value R1, R2 is calculated for each of the factors M1, M2, wherein each auxiliary value R1, R2 is the modular inverse of the value E in relation to the respective factor M1, M2 as module, and the modular inverse R is calculated at least using the calculated auxiliary values R1, R2. A computer program product and a portable data carrier have corresponding features. The invention provides a method for modular inversion which is efficient when performed by a machine, the method in particular being suitable for use for cryptographic calculations on a portable data carrier.</p> |
