AN AUTHENTICATION TOKEN FOR IDENTIFYING A CLONING ATTACK ONTO SUCH AUTHENTICATION TOKEN

摘要

The invention relates to an authentication token (10) for a communication network comprising a microprocessor (11), a memory (12), a stored secret key (Ki) and a set of instructions for controlling the microprocessor (11) into performing an authentication calculation on the basis of a received random (RAND) and on the basis of the stored secret key, characterized in that it includes a memory location dedicated for storing a counter value and it includes instructions for making the counter value evolve each time the authentication calculation is performed.