DATENAUSTAUSCHSYSTEM.

摘要

A custom chip card (KK) used with a custom terminal (KT) generates a random number (v) to select individual parts (Pv) from a data flow control program (P). An authentication code (PACv) is formed from the selected subroutine (Pv) with the aid of an authentication algorithm (f) and a secret key (KPC). The codes worked out by the card (KK) and by the terminal (KT) are matched by a comparator (COMP) incorporated in the card. The secret key (KPC) may be either kept in a secure PROM or transferred to the terminal from a special chip card.