Securement of optical fibers against eavesdropping using jamming signals

Abstract

A method is provided for securement of a network of optical fibers against attempts to detect sounds such as private conversations emitted in the vicinity of the fiber network such as in a secure room. The cable entering the room contains a plurality of fibers some of which have data and some are unused. It has been found that the sensitivity of systems such as DAS monitoring systems can detect such conversations from the vibration of the fibers in the vicinity. The method includes monitoring at least some of the fibers for detecting transmission therealong of light signals used for monitoring of fiber vibration which provide information on the sounds. An indication alert is emitted when detected of an intrusion attempt. A jamming signal can be transmitted along the detected fiber to prevent the monitoring. The monitoring and jamming can take place at a patch panel where the fibers are connected.

Dependencies are inferred from the claim text.