PROCEDE DE PROTECTION D'UNE CLE MERE DESTINEE A PERMETTRE L'AUTHENTIFICATION DE CARTES UTILISATEURS

摘要

The invention concerns a method for protecting a parent security key (KM1)for authenticating user cards with a reader comprising a security application module (SAM), characterised in that: a first part of the parent security key (KM11) is stored in a memory of the security module (SAM); a second part of the parent security key (KM12) is stored in a supervisory card (CS) memory; and a temporary copy of the second part of the parent security key (KM12) is brought by the supervisory card (CS) into a memory of the security module (SAM). The invention is applicable in particular to closed systems such as the cash-desks of department stores or slot machines of a casino for example.