Fremgangsmåte og anordning for å autentifisere en databærer innrettet for å tillate en transaksjon eller aksess til en tjeneste eller et sted, samt slik databærer

摘要

The system uses an electronic card (1), a central computer (4) and a sales point terminal (8). The electronic card (1) carries a card number (Ns) and an authentication value (VA). The central computer (4) has processing circuits (5) and memory (6) containing a cryptographic disymmetric algorithm (F) and secret key (Ks). The sales point terminal (8) contains processing circuits (9) and a memory (10) which stores an inverse algorithm (G) and public key (Kp). The authentification value (VA) is intially found by the central computer and placed on the card and in subsequent transactions the card number (Ns) and user information (I) are checked by the sales terminal using the inverse algorithm and public key (Kp).