Patent ID: 7035386

Claim:
A method of verifying access authorization for voice telephony for a fixed network line or a mobile telephone line, comprising: providing a first voice signal of a first subscriber placing a telephone call; analyzing the first voice signal via a voice recognition algorithm when one of (a) before a communication connection between the first subscriber and a second subscriber is established and (b) after the communication connection between the first subscriber and the second subscriber is established, and if the analyzing begins after the communication connection between the first subscriber and the second subscriber is established then the first voice signal and a second voice signal of the second subscriber continue to be relayed; comparing the first voice signal with a voice reference data record to determine an identity of the first subscriber; determining if the first voice signal is in the voice reference data record and if the first voice signal is not in the voice reference data record then at least one communication effect occurs, the at least one communication effect including not establishing the communication connection, automatically interrupting the communication connection and generating an alarm in the communication connection; recording the first voice signal before and after a communication connection to the second subscriber is established; assigning the voice reference data record to the fixed network line or the mobile telephone line; and recording a voice sample of the first subscriber and the second subscriber at regular time intervals during the communication connection and checking the first and second voice signals with the voice reference data record.