| abstract |
The present invention relates to a test method, wherein a test method is characterized in that when separate cryptographic operations (OPRK) applied to the same confidential data (SD) are executed, each set of values is associated with a physical quantity associated with the activity of the circuit For each set of values, counting the number of occurrences (HT) of the set of values, for each set of values, for each set of values (g Calculating a partial result (VL) of the task, calculating a sum (CH) of occurrences, wherein each sum, when applied to some possible equal one of the confidential data, Computing the sum of the number of occurrences corresponding to the jobs providing the result, and analyzing the sum of the occurrences to determine some of the confidential data. |