A method of authentication in a communications network, said communications network comprising a network authentication server, a local authentication entity and a user terminal, said local authentication entity comprising a subscriber application and an authentication application, said method comprising the steps of: sending a request from the local authentication entity to the network authentication server to authenticate the user terminal, said request comprising the identity of the user terminal; generating by the network authentication entity an authentication key in response to the request and generating by the subscriber application an identical authentication key; sending the authentication key generated by the network authentication server securely to the user terminal identified by said identity, then storing the authentication key at the user terminal; sending the authentication key generated by the subscriber application securely to the authentication application, then storing the authentication key at the authentication application; and authenticating the user terminal by verifying the authentication key stored at the user terminal with the authentication key stored at the authentication application.