Fiber sensing control device

1 . A system comprising at least a first of one or more network segments, wherein at least the first network segment comprises:

a network infrastructure ( 105 );

at least one optical fiber cable ( 115 , 120 ) communicatively connected to the network infrastructure; and

one or more fiber sensing control devices (FSCDs) ( 100 ) for control of fiber sensing of the first network segment;

wherein:

each of the FSCDs is located on a respective one of the optical fiber cables at a boundary between the first network segment and a region of said respective one of the optical fiber cables that is vulnerable to fiber sensing;

each of the FSCDs is dedicated for the purpose of controlling the fiber sensing on at least one fiber ( 115 , 120 ) of its respective optical fiber cable; and

each of the FSCDs comprises at least one blocking element ( 125 , 130 , 240 ) that is controllable to block sensing of backscattered light on at least one fiber under control of said FSCD by blocking injected fiber-sensing probe pulses from entering the first network segment from the vulnerable region, and/or by blocking fiber-sensing backscattered light from entering the vulnerable region from the first network segment.

2 . The system of claim 1 , wherein the at least one blocking element comprises an optical isolator ( 125 , 130 ).

3 . The system of claim 2 , wherein at least the first one of the FSCDs further comprises an SoP unit ( 310 ) comprising a polarization scrambler on at least one fiber under control of said FSCD.

4 . The system of claim 1 , wherein at least one of the FSCDs comprises a local control unit ( 205 , 300 ) for activating and deactivating its at least one blocking element ( 125 , 130 , 240 ).

5 . The system of claim 1 , wherein at least a first one of the FSCDs comprises, on each fiber under control of said FSCD:

a pass-through path ( 210 , 255 , 220 , 225 ) for communication signals;

a bypass path ( 235 , 245 ) for backscattered signals; and

an optical gate ( 240 ) for controllably allowing and blocking the backscattered signals.

6 . The system of claim 5 , wherein at least the first one of the FSCDs further comprises:

a local control unit ( 205 , 300 ) for opening and closing the optical gate; and

a diversion path ( 255 , 260 ) for diverting, to the local control unit, a portion of communication signals that enter said FSCD.

7 . The system of claim 6 , wherein the local control unit ( 205 ) is configured to detect a command signal in the diverted signal portion, and to respond to the command signal by activating the optical gate to open or close.

8 . The system of claim 6 , wherein the local control unit ( 300 ) is configured to detect a signal pattern indicative of an intrusion attempt in the diverted signal portion, and to respond to the detected pattern by activating the optical gate to close.

9 . The system of claim 6 , wherein:

at least the first one of the FSCDs further comprises a real-time sensing agent ( 305 );

the real-time sensing agent is configured to detect intrusion attempts; and

the real-time sensing agent is further configured to respond to a detected intrusion attempt by sending an activation signal to the controller ( 300 ).

10 . The system of claim 6 , wherein:

the FSCD further comprises an SoP unit ( 310 ) comprising a polarization scrambler and a controller for the polarization scrambler on at least one fiber under control of said FSCD; and

the real-time sensing agent ( 305 ) is further configured to respond to a detected intrusion attempt by sending an activation signal to the controller of the SoP unit to activate the polarization scrambler.

11 . The system of claim 1 , wherein:

the system comprises a plurality of network segments ( 410 ), each of which is protected by one or more FSCDs ( 405 ) that collectively constitute an FSCD plurality;

each FSCD of the FSCD plurality controls fiber sensing on at least one fiber ( 115 , 120 ) of a respective optical fiber cable;

each FSCD of the FSCD plurality comprises, on each fiber under its control, a pass-through path ( 210 , 255 , 220 , 225 ) for communication signals, a bypass path ( 235 , 245 ) for backscattered signals; and at least one optical gate ( 240 ) for controllably allowing and blocking the backscattered signals;

each FSCD of the FSCD plurality further comprises a local control unit ( 205 , 300 ) for opening and closing its respective at least one optical gate; and

each of the network segments of the network-segment plurality further comprises a sensing network controller ( 415 ) configured to send control signals to the respective local control units ( 205 , 300 ) of the FSCDs belonging to that network segment.

12 . The system of claim 11 , further comprising a sensing network orchestrator ( 420 ), wherein:

the sensing network orchestrator is communicatively connected to the sensing network controller ( 415 ) of each of the network segments ( 410 ) of the network-segment plurality;

the sensing network orchestrator is configured to orchestrate control of the FSCDs across the plurality of network segments; and

each sensing network controller ( 415 ) is configured to send control signals to the respective local control units ( 205 , 300 ) of the FSCDs belonging to its respective network segment in response to orchestration signals that it receives from the sensing network orchestrator.

13 . A method of permissively controlling fiber sensing of a network infrastructure ( 105 ) situated within at least a first network segment of a communication network, comprising activating at least one fiber-sensing control device (FSCD) ( 100 ) located on a respective optical fiber cable at a boundary between the first network segment and a neighboring network segment in a region of said respective optical fiber cable that is vulnerable to fiber sensing,

wherein:

the at least one FSCD is dedicated for the purpose of controlling fiber sensing on one or more fibers ( 115 , 120 ) of its respective optical fiber cable; and

the activating of the at least one FSCD comprises causing each of one or more blocking elements ( 125 , 130 , 240 ) to block sensing of backscattered light on one or more fibers under control of said at least one FSCD by blocking injected fiber-sensing probe pulses from entering the first network segment from the vulnerable region, and/or by blocking fiber-sensing backscattered light from entering the vulnerable region from the first network segment.

14 . The method of claim 13 , wherein the activating of the at least one FSCD comprises activating an optical isolator ( 125 , 130 ).

15 . The method of claim 14 , wherein the activating of the at least one FSCD further comprises activating a polarization scrambler on one or more fibers under control of said FSCD.

16 . The method of claim 14 , wherein the activating of the at least one FSCD comprises causing an optical gate ( 240 ) to close so as to block backscattered signals from entering one or more fibers under control of said FSCD.

17 . The method of claim 16 , wherein:

the method further comprises diverting at least a portion of communication signals entering the at least first one of the FSCDs to a local control unit ( 205 ) configured to detect a command signal in the diverted signal portion; and

the causing of an optical gate ( 240 ) to close is performed in response to detection of a command signal in the diverted signal portion.

18 . The method of claim 16 , wherein:

the method further comprises diverting at least a portion of communication signals entering the at least first one of the FSCDs to a local control unit ( 300 ) configured to detect a signal pattern indicative of an intrusion attempt in the diverted signal portion; and

the causing of an optical gate ( 240 ) to close is performed in response to detection of a signal pattern indicative of an intrusion attempt in the diverted signal portion.

19 . The method of claim 18 , further comprising activating a polarization scrambler on one or more fibers under control of said at least one FSCD in response to detection of a signal pattern indicative of an intrusion attempt in the diverted signal portion.

20 . The method of claim 13 , wherein:

the communication network comprises a plurality of network segments ( 410 ), each of which is protected by one or more FSCDs ( 405 ) that collectively constitute an FSCD plurality;

each FSCD of the FSCD plurality controls fiber sensing on at least one fiber ( 115 , 120 ) of a respective optical fiber cable;

each FSCD of the FSCD plurality comprises a local control unit ( 205 , 300 ) for activating and deactivating its respective at least one blocking element;

each of the network segments of the network-segment plurality further comprises a sensing network controller ( 415 ) configured to send control signals to the respective local control units ( 205 , 300 ) of the FSCDs belonging to that network segment;

the activating of the at least one FSCD comprises sending one or more first control signals from a sensing network orchestrator ( 420 ), and sending one or more second control signals from at least one sensing network controller ( 415 );

the first control signals are sent from the sensing network orchestrator to the sensing network controllers ( 415 ) of selected networks;

the second control signals are sent by the sensing network controllers of the selected networks in response to the first control signals;

each second control signal is sent by a sensing network controller to the local control unit of each of one or more FSCDs within the sensing network controller's own network segment; and

each local control unit responds to a received second control signal by activating a respective blocking element.