摘要 |
Method of authenticating a client comprising the steps of sending a subscriber identity to an authentication server; obtaining at least one challenge and at least one first secret to the authentication server based on a client's secret specific to the client; forming first credentials; forming a first authentication key using the at least one first secret; encrypting the first credentials using the first authentication key; sending the at least one challenge and the encrypted first credentials to the client; forming an own version of the first authentication key at the client; decrypting the encrypted first credentials using the own version of the first authentication key. In the method, the encrypted credentials are sent together with the at least one challenge to the client so that the client can proceed authentication only if it can derive the first secret from the at least one challenge. |