Monotonic counter realizing method for e.g. mobile telephone, involves storing counting function, counter and private key in persistent memory of smart card e.g. subscriber identity module card

摘要

The method involves storing a counting function, a monotonic counter and a private key that is stored in a part of a read protected memory zone, in a persistent memory of a smart card e.g. subscriber identity module (SIM) card. Modification of the counter, calculation of a signature and sending of a response are executed by the counting function during the reception of a request of the counter by the card. The signature contained in the response is verified during the reception of the response to the counter request by an embarked computational system e.g. mobile telephone.