METHOD FOR EXECUTING AN ENCRYPTION PROGRAM IN A MICROPROCESSOR-ASSISTED, PORTABLE DATA CARRIER

摘要

The invention relates to a method, in which the data to be encrypted is linked by a random number using an exclusive-OR operation prior to encryption. According to the invention, the encryption program is modified in such a way that the standard encryption text can be ultimately retrieved. The inventive method provides protection against the DPA (Differential Power Analysis) attack.