Method and device for detecting the unauthorized use of a telephone line

The inventive method for protecting a telephone line consists of establishing an electrical signature using the parameters of the line when it is being used by the authorized telephone, and comparing this signature each time the line is used. If the two signatures differ, the line is subjected to a...

Full description

Saved in:
Bibliographic Details
Main Author JACQUES LABIE
Format Patent
LanguageEnglish
Published 13.03.2002
Edition7
Subjects
ELECTRIC COMMUNICATION TECHNIQUE
ELECTRICITY
TELEPHONIC COMMUNICATION
Online AccessGet full text

Cover

More Information
Summary:The inventive method for protecting a telephone line consists of establishing an electrical signature using the parameters of the line when it is being used by the authorized telephone, and comparing this signature each time the line is used. If the two signatures differ, the line is subjected to a certain measure: either the line is interrupted or a noise is produced, making any use impossible. The surveillance module (3) for carrying out this method is connected to a telephone line (4) in order to prevent the telephone line from being used by an unauthorized telephone. This module is provided with means for measuring the electrical parameters of the line during a communication and with means for comparing this signature with a reference signature. The module generates a signal on the line or interrupts the line if the signatures are different.
Bibliography:Application Number: GB20010030157