A method for verifying access authorization for voice telephony in a fixed
network line or mobile telephone line, as well as a communications
network having such access authorization verification are described. The
access authorization is verified by analysis of a voice signal which was
entered by the subscriber placing the call, before or during a call in
progress. In one variant, the voice signal is entered as a password
before the connection is established; in another variant, voice signals
are analyzed for voice recognition and subscriber identification, the
same voice signals also being transmitted to the person being called,
making concealed access verification possible which does not hamper the
normal flow of conversation.