Controlling link related security functions

摘要

The method involves conducting a subscriber authentication between the mobile station (MS) and the communications network (PLMN) to check access authorisation as soon as a link is initiated by the mobile station. A key request for retaining the secrecy of the information on the interface (AIF) is sent to the mobile station from the communications network. The key request is received by the mobile station and evaluated with an identifier showing whether the communications network requires a connection to the radio interface with encoded information or with unencoded information. The mobile station can be switched over under subscriber control to an operating mode in which the connection is broken if the received identifier permits a connection with unencoded information.