Patent ID: 8909923

Claim:
A security method in a terminal comprising a chip card offering secure functions, a user interface, an interface module for interface with the chip card and operable for at least shutting down or introduction of an electrical supply to the chip card, the method comprising the steps of: receiving a code through the user interface of the terminal; receiving the code by the chip card from the interface module; verifying by the chip card that the code is equal to an access code and utilizing by the interface module the secured functions offered by the chip card on verification of the code; negotiating between the interface module and the chip card of at least one key (K encryption1 , K signature1 ), storing said at least one negotiated key by the interface module and by the chip card; shutting down and introducing the electrical supply to the chip card by the interface module with the terminal kept switched on; encrypting a command for resuming the utilization of the secure functions by the interface module with said at least one negotiated key stored in the interface module; receiving said encrypted command by the chip card from the interface module; decrypting said encrypted command by the chip card using said at least one negotiated key stored in the chip card; and utilizing by the interface module of the secure functions of the chip card when said encrypted command decrypted by the chip card is recognized as a resumption command by the chip card.