摘要 |
Method of authentication in a system comprising two entities communicating between themselves by way of a network, a first entity (CARD) authenticating a second one (SERVER) and data received from said second entity, each entity storing the same secret key K, said first entity receiving a message authenticating code (MAC) and other parameters (RAND, SQN, AMF, ...), the message authenticating code calculation including the key K and said other parameters (RAND, SQN, AMF, ...), the authentication procedure consisting in challenging the received code (MAC) and an expected code (XMAC), the expected code being computed in using the received parameters and the key K stored in said first entity, characterized in that each time the two codes (MAC, XMAC) don't match, the authentication procedure is aborted, a failure counter storing the number of occurrences of abortion. <IMAGE> |