Method to prevent hidden communication on a channel during device authentication, corresponding vplmn and hplmn

Abstract

The disclosure concerns a method for preventing transmission of hidden information in a communication channel during a telecommunication terminal authentication phase including transmitting from a telecommunication terminal cooperating with a secure element to a visited PLMN a unique identifier of the secure element; generating at the visited PLMN a required information and sending the unique identifier and the required information to a home PLMN identified by a MCC/MNC in the unique identifier; generating a random value and computing a cryptographic value based on the random value and the required information; generating an authentication vector based on the cryptographic value and the long term key of the secure element, the long term key being associated to the unique identifier, and sending the authentication vector and the random value or only the authentication vector containing the random value instead of the cryptographic value to the visited PLMN.