Abstract: A secure electronic entity, adapted to store at least one object, includes a unit for measuring the passage of time as from a reference date associated with the object. It includes a unit for storing a life span assigned to the object co-operating with the time measuring unit so as to compare the time elapsed and the life span. It further includes an updating and invalidating unit, to update the object life span or to temporarily or permanently disable the object if the comparison shows that the time elapsed exceeds the life span. The invention is in particular applicable to smart cards.

Abstract: The invention concerns a secure electronic entity (11), adapted to store at least one object, comprising a unit (18) for measuring the passage of time as from a reference date (Dref) associated with said object. It comprises a unit (19) for storing a life span (V) assigned to said object co-operating with the time measuring unit (18) so as to compare the time elapsed and the life span (V). It further comprises an updating and invalidating unit (21), to update the object life span or to temporarily or permanently disable the object if the comparison shows that the time elapsed exceeds the life span (V). The invention is in particular applicable to smart cards.

Abstract: Authentication of a smart card is accomplished utilizing a microcomputer (PC) provided with an internal reader (RD) and an electronic circuit (3) linked to the PC. The circuit (3) includes a microprocessor (MP) capable of generating a random factor (RN). The circuit (3) also includes a startup circuit (MCD) generating a time delay period T, a security microcircuit (PSMC) and a blocking circuit (BBC). Between these elements, a cryptographic procedure, of the DES or DEA type, is effected which aims at establishing the consistency between a key (SK2I) associated with dedicated identity numbers (IN, OPN) of the smart card (CAM) and a key (SK2I') associated with a corresponding dedicated identity number (IN') of the PC in the PSMC. The system is automatically blocked in the case of inconsistency.