Optical transport network equipment channel security detection system and method based on quantum measurement

Abstract

The invention relates to optical fiber channel security detection, in particular to an optical transport network equipment channel security detection system and method based on quantum measurement and an optical time domain quantum detection device, which are used for carrying out signal detection with high spatial resolution and large dynamic range based on quantum measurement and realizing high-precision sensing of multi-dimensional parameters of an optical fiber channel. The main control software is applied to realize equipment control, data processing and analysis based on an artificial intelligence algorithm and application layer communication; the optical transport network equipment performs information interaction with the application master control software through the management and control system and executes a corresponding security policy; the wave combination control module is used for carrying out beam combination on the optical signal output by the optical time domain quantum detection device and a service signal output by the optical transport network equipment, entering an optical fiber channel and controlling to switch a detection line; according to the technical scheme, the defects that high-spatial-resolution and large-dynamic-range signal detection is difficult to carry out, and accurate event type judgment and high-precision spatial discrimination cannot be carried out on tiny loss events can be overcome.

Description

Technical Field

[0001] The present invention relates to optical fiber channel security detection, and in particular to an optical transmission network equipment channel security detection system and method based on quantum measurement. Background Art

[0002] Fiber-optic communication networks present varying degrees of security risks. Widely distributed communication lines, in particular, lack security measures due to technical, investment, and deployment difficulties, resulting in significant security risks for communications services. Fiber-optic transmission lines are the primary medium for information transmission in modern communication systems and the foundational resource for high-speed, long-distance optical data transmission. Their security is a crucial component of infrastructure security. Currently, unauthorized individuals can gain access to optical cables or transmission equipment and conduct destructive attacks such as eavesdropping or interference.

[0003] For feedback on the status of the optical fiber channel at the physical layer of the optical transport network, traditional optical transport network equipment obtains parameters such as the communication bit error rate through the optical monitoring channel for evaluation. Since covert eavesdropping does not affect the system's communication status, optical monitoring cannot achieve eavesdropping perception.

[0004] Optical transport networks (OTNs) use traditional optical time-domain reflectometers (OTDRs) as a means of locating line faults, rather than as a security measure. When the OTN monitoring channel detects a line fault, the OTDR is activated to locate the fault point. Due to the limited sensitivity of traditional OTDRs, they can only detect highly varying signals such as end events, reflection events, and large attenuation events. They are unable to achieve high-precision spatial resolution for small loss events, making them ineffective in detecting eavesdropping attempts. Furthermore, as the detection distance increases, the required transmitted light intensity also increases, potentially causing crosstalk with the OTN signal. Furthermore, because traditional OTDRs use low-repetition-bandwidth pulses for detection, there is a trade-off between spatial resolution and dynamic range. This means they cannot accurately locate events simultaneously over long optical fiber distances, and cannot accurately distinguish between two events that are close in distance. Summary of the Invention

[0005] In response to the above-mentioned shortcomings of the existing technology, the present invention provides a channel security detection system and method for optical transport network equipment based on quantum measurement, which can effectively overcome the defects of the existing technology in that it is difficult to perform signal detection with high spatial resolution and large dynamic range, and it is impossible to accurately determine the event type and perform high-precision spatial resolution of tiny loss events.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: The optical transport network equipment channel security detection system based on quantum measurement includes an optical time-domain quantum detection device, application master control software, optical transport network equipment, and a multiplexing control module; Optical time-domain quantum detection device, based on quantum measurement, performs signal detection with high spatial resolution and large dynamic range, achieving high-precision perception of multi-dimensional parameters of optical fiber channels; Apply master control software to achieve device control, data processing and analysis based on artificial intelligence algorithms, and application layer communication; Optical transport network equipment exchanges information with application master control software through the management and control system to implement corresponding security policies; The combining control module combines the optical signal output by the optical time domain quantum detection device with the service signal output by the optical transmission network equipment, enters the optical fiber channel, and switches the detection line in a controlled manner.

[0007] Preferably, the optical time-domain quantum detection device includes a light source, a first attenuator, a circulator, a filter, a second attenuator, a single photon detector, and a signal driving and processing module; A light source generates a pump light signal to stimulate Rayleigh scattering signal / Brillouin scattering signal / Raman scattering signal; a first attenuator, controlling the intensity of the optical signal output by the optical time-domain quantum detection device to be within the safe operating range of the single-photon detector; The circulator couples the optical signal scattered back from the optical fiber channel to be tested into the detection optical path; The filter suppresses noise on optical transmission network line signals while supporting high transmittance of optical signals output by the optical time-domain quantum detection device, including Rayleigh scattering wavelengths, Brillouin scattering wavelengths, and Raman scattering wavelengths; The second attenuator realizes the synchronous attenuation control of the optical signal intensity detected by the optical time-domain quantum detection device and the signal noise of the optical transmission network line, so that the single photon detector is within the safe operating range; Single-photon detector, which can detect weak optical signals at the single-photon level and convert optical signals into electrical signals; The signal driving and processing module provides driving signals for the light source, the first attenuator, the second attenuator and the single-photon detector, and processes the detection signals.

[0008] Preferably, the light source is a narrow pulse laser with adjustable pulse width in the range of picoseconds to microseconds. Since the spatial resolution accuracy is inversely correlated with the pulse width, and the optical fiber measurement range is inversely correlated with the repetition frequency of the optical signal, the preparation of low repetition rate and wide bandwidth pulses is achieved by splicing narrow pulses in sequence. That is, assuming that the period of the laser outputting high repetition rate narrow pulses is t, the required period of the low repetition rate and wide bandwidth pulses is T, and the required duty cycle is n%, then within the T*n% time, T*n% / t high repetition rate narrow pulses are sent, and no light is emitted at the time T*(1-n%), so as to obtain low repetition rate and wide bandwidth pulses by splicing within this time domain, so that the optical time domain quantum detection device can perform signal detection with high spatial resolution and large dynamic range.

[0009] Preferably, the first attenuator and the second attenuator work in conjunction with each other: When the optical time-domain quantum detection device is started to detect the environmental status, the attenuation degree of the first attenuator is the largest, and the attenuation degree of the second attenuator gradually decreases from large to small, so that the noise signal is gradually and controllably enhanced and enters the single-photon detector, confirming that the operating environment is safe; During the self-test of the optical time-domain quantum detection device, the attenuation of the first attenuator gradually decreases from high to low, and the attenuation of the second attenuator is the lowest, so that the optical signal gradually enters the single-photon detector, confirming that the laser light emission state is normal; When the signal-to-noise ratio of the detection signal is low, the attenuation degree of the second attenuator increases, which reduces the overall intensity of the optical signal and the noise signal. At the same time, the attenuation degree of the first attenuator decreases, which relatively enhances the optical signal. When the signal-to-noise ratio of the detection signal is high, the attenuation degree of the second attenuator is reduced, and at the same time the attenuation degree of the first attenuator is adjusted according to the strength of the detection signal; The first attenuator includes an electro-optic modulator, an acousto-optic modulator, or a MEMS attenuator; the single-photon detector operates in the near-infrared band, and the operating mode is a gated trigger mode or a free mode.

[0010] Preferably, the first attenuator controls the light intensity to gradually increase in a step-like manner after a certain length in the direction of optical fiber transmission through distributed optical intensity control, so as to compensate for the reduction in optical signal count caused by optical fiber loss, avoid the saturation of short-distance optical signal count and the low long-distance optical signal count, and realize dynamic range superposition through distributed optical intensity control: S11. Evaluate the interval length of distributed light intensity control and the dynamic range limit DR-max of the single-photon detector based on the fiber length, laser output intensity, and detector saturation count. Suppose the total fiber length is L, which is divided into three segments: L1, L2, and L3. The corresponding time intervals of the light reflection signal are T1, T2, and T3. S12, controlling the first attenuator so that the initial output light intensity of the L1 segment optical fiber is P0, obtaining a photon count and arrival time curve in the T1 period, and calculating the dynamic range DR1 of the T1 period; S13, controlling the first attenuator so that the initial output light intensity of the optical fiber L2 is close to P0, obtaining a curve of photon counts and arrival times in time period T2, and simultaneously shutting down the detector in time period T1, or discarding the counts due to count saturation, and calculating the dynamic range DR2 in time period T2; S14, controlling the first attenuator so that the initial output light intensity of the optical fiber section L3 is close to P0, obtaining a curve of photon counts and arrival times in time period T3, and simultaneously shutting down the detector in time periods T1 and T2, or discarding counts due to saturation, and calculating the dynamic range DR3 of time period T3; S15, splicing the photon count and arrival time curves in the time periods T1, T2, and T3 to form a complete photon count and arrival time curve within the length L, and drawing a loss-fiber length curve based on the fiber refractive index and ranging principle; Ideally, DR1=DR2=DR3=DR-max. Distributed light intensity control according to the above process can achieve a multiple increase in dynamic range after superposition.

[0011] Preferably, the optical time-domain quantum detection device is based on single-photon quantum measurement technology and high-precision spatial resolution technology to perform signal detection with high spatial resolution and large dynamic range. The optical time-domain quantum detection device adopts a variety of optical time-domain quantum measurement technologies including Rayleigh scattering signals, Brillouin scattering signals, and Raman scattering signals, and supports the measurement and analysis of a variety of working parameters and safety risk parameters including vibration, temperature, attenuation, breakpoint, bending, clamping, and spectrometry. When the optical time-domain quantum detection device is measuring attenuation and breakpoint parameters and the test signal is a Rayleigh scattering signal, the filter operating wavelength is the same as the laser wavelength. To suppress optical transmission network line noise, the operating bandwidth is narrow, no more than 100 GHz, to improve the survivability of the device in noisy environments. When the optical time-domain quantum detection device performs attenuation and breakpoint working parameter measurements and the test signal is a Brillouin scattering signal or a Raman scattering signal, the filter operating wavelength is correspondingly the Brillouin scattering wavelength or the Raman scattering wavelength; When there is more than one optical time-domain quantum detection device, a wavelength division multiplexing mode or a time division multiplexing mode is adopted for co-fiber transmission.

[0012] Preferably, the application main control software has a device control function and a parameter setting function, and the parameter setting includes the optical fiber measurement range, measurement time and measurement pulse width parameter setting; The application master control software has data processing and analysis functions based on artificial intelligence algorithms, including convolutional neural networks (CNN), artificial neural networks (ANN), and K-nearest neighbor algorithms (KNN), and supports nonlinear supervised learning analysis using a combination of fiber channel detection data and optical transport network monitoring data; The application master control software has the function of displaying the optical fiber channel detection results and abnormal state alarm display; The application master control software has optical transport network equipment communication functions, including information exchange such as alarm and detail reporting and detection command issuance, and also has security policies for adaptive adjustment of optical transport network equipment in the application environment; The application master control software has an open protocol and can adapt to optical transport network equipment of different brands to achieve information exchange and resource sharing.

[0013] Preferably, the wave combining control module is integrated into an optical time domain quantum detection device or an optical transport network device, and the wave combining control module includes a 1*N optical switch and a combiner; 1*N optical switch, with the number of channels not less than the number of communication lines connecting the nodes, to switch between multiple communication lines connecting the nodes and implement roll call testing / periodic testing / alarm trigger start testing; The combiner, whose operating wavelength covers the operating wavelength of the optical time-domain quantum detection device and the optical transport network equipment, combines the optical signal output by the optical time-domain quantum detection device with the service signal output by the optical transport network equipment and transmits them into the same optical fiber channel. This solves the demand for optical fiber resources for optical fiber channel detection, achieves inter-sensing integration, and reduces deployment costs. Among them, the combiner supports two-channel output, distributing the optical signal output by the optical time-domain quantum detection device and the service signal output by the optical transmission network equipment to the two optical fiber cores in the same optical cable respectively.

[0014] A quantum measurement-based optical transport network equipment channel security detection method, applied to the aforementioned quantum measurement-based optical transport network equipment channel security detection system, mainly including quantum measurement, event analysis, service decision-making and algorithm training; Quantum measurement, which enables parameter measurement of optical fiber channels of optical transport network equipment; Event analysis and business decision-making: Using artificial intelligence algorithms to analyze event types and conduct security assessments on fiber channel detection results; Algorithm training analyzes system security parameter thresholds based on environmental evolution, adaptively adjusts security parameter thresholds, improves algorithm model accuracy, and provides fiber channel environmental trend assessment to achieve security risk early warning; The detailed process is as follows: S1. Check whether the control system receives a parameter abnormality alarm. If so, it switches to alarm link detection first and connects to the corresponding fiber channel to be tested after receiving a roll call test or periodic test command. S2. Start the quantum measurement process, trigger the single-photon detector, turn off the narrow pulse light source, and detect the background signal. If the detector count is abnormal, the main control software will determine the event type based on the abnormal data and report the device failure or line status abnormality details. If the fiber channel environment is normal and the detector count is normal, the next self-test will be carried out; S3: Trigger the light source and perform a self-test. If the light source status is abnormal, the device fault is reported. If the light source status is normal, the parameters are automatically set, spliced low-repetition-frequency wideband pulses are output, and distributed optical intensity control is performed to achieve characteristic value measurement of optical fiber channel operating parameters and safety risk parameters. S4. The main control software is used to continuously collect measured characteristic values and process and analyze the line detection data using artificial intelligence algorithms. Based on the analysis results, the line operation and safety status are determined. The training database is updated based on the currently collected data. If the line safety status is normal, the normal test results are reported in the roll call test, or optical time domain quantum detection is continuously performed in the periodic test. If the line safety status is abnormal, the event type is determined and an alarm is reported. The optical transport network equipment then regulates the equipment operation status based on the safety risk level. S5. After receiving the test results or alarm information, the optical transport network equipment executes the corresponding security policy. If there is no security risk on the line, business communication continues; if the event type is determined to be a device failure or abnormal line status, the equipment or line is notified for maintenance; if there is still a security risk on the line, business communication is terminated and the backup link communication is switched; if there is a risk of parameter quality deterioration on the line, the equipment or line is notified for maintenance or preventive inspection.

[0015] Preferably, the security policy includes: 1) Equipment security registration: When the optical time-domain quantum detection device is used for the first time, the main control software is used to report information including the module model and version number to the management and control system. After passing the authentication, the device obtains the online work permission; 2) High-light protection strategy: After the optical time-domain quantum detection device is put into operation, a self-test process is initiated to confirm that there is no risk of damage to the single-photon detector. Then, through light intensity control and measurement, the module is confirmed to be operating normally, and information including the module model and version number is reported to the management and control system. If the module is operating abnormally or the working environment poses a risk of damage to the single-photon detector, the module is reported as abnormal and operation is stopped. 3) Detection sensitivity improvement strategy: The optical time-domain quantum detection device uses narrow pulse timing splicing. By controlling the number of pulses sent in a single cycle and the number of vacuum pulses sent, it can achieve low repetition rate and adjustable width pulse preparation. This allows the measurement scheme to combine the advantages of high spatial resolution brought by high repetition rate narrow pulses with the wide dynamic range brought by low repetition rate wide pulses. 4) Dynamic range improvement strategy: The optical time-domain quantum detection device uses distributed light intensity control to control the step-wise increase of light intensity in the direction of optical fiber transmission to compensate for signal loss caused by continuous fiber loss, avoid saturation of optical signal counts over short distances and low optical signal counts over long distances, and achieve the dynamic range of conventional measurements within a single area. Through distributed light intensity control, the dynamic range of multiple intervals can be superimposed, thereby effectively improving the dynamic range of the system; 5) Event type determination strategy: Event types include end, reflection, attenuation, vibration, and temperature. End events, reflection events, large attenuation events, large dynamic vibration events, and temperature change events can be directly detected using an optical time-domain quantum detection device. For small loss events such as breakpoints, splitting, bending, and clamping, as well as small vibration and temperature change events, an artificial intelligence algorithm is used to perform nonlinear supervised learning analysis using combined data to accurately determine the event type. 6) Optical time-domain quantum detection device trigger mechanism: supports automatic startup at power-up or parameter anomaly triggering, including triggering when events such as loss anomalies and bit error rate anomalies are reported. In integrated quantum key distribution encryption communication systems, it supports instant triggering based on abnormal phenomena, including jumps in the bit error rate of the quantum key distribution system, to achieve parameter anomaly analysis and location. 7) Working Mode: Supports manual scanning and automatic scanning. In manual scanning mode, commands are issued through the management and control system to control the start of the target line optical time domain quantum detection device. In automatic scanning mode, it supports parameter abnormality triggering, as well as long-term online or timed periodic detection of single channels. For one-to-many communication nodes, it supports multi-channel optical switch switching to achieve multi-line patrol testing, and reports abnormal events through the management and control system. 8) Alarm prompt: Based on quantum measurement and artificial intelligence analysis, if the system has performance anomalies or security risks, the main control software will report the alarm information and abnormal information details to the management and control system and display them on the interface.

[0016] Compared with the existing technology, the optical transport network equipment channel security detection system and method based on quantum measurement provided by the present invention has the following beneficial effects: 1) The optical time-domain quantum detection device proposed in this invention generates low-repetition-frequency wide pulses by splicing narrow pulse sequences and adopts distributed optical intensity modulation, which combines the advantages of high spatial resolution and large dynamic range, effectively improving the performance of optical time-domain detection technology. 2) The proposed quantum measurement-based optical transport network equipment channel security detection system, combined with AI-powered data analysis, improves the sensitivity, location accuracy, and event type determination of minor loss events such as breakpoints, splitting, bending, and clamping. It also supports predictive assessment of line status based on machine learning. 3) The optical transport network equipment channel security detection system proposed in this invention, based on quantum measurement, uses single-photon detection technology, with detection sensitivity several orders of magnitude higher than that of teleporting photodiodes. The system's light source only requires a low-intensity output, which will not interfere with other signals in the existing optical fiber channel and can continuously perform detection work in the line. 4) The application master control software proposed in the present invention has an open protocol, which allows information exchange and resource sharing with the optical transport network equipment management and control system, providing it with real-time dynamic monitoring and quality analysis, and timely reporting of alarm information. The optical transport network equipment promptly adjusts the communication status or switches the communication link based on the alarm information. Through a collaborative working mechanism, the confidentiality, integrity, and availability of the physical channel of the optical transport network are ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0018] Figure 1 A schematic diagram of the system of the present invention; Figure 2 For the present invention Figure 1 Schematic diagram of the structure of the Zhongguang time-domain quantum detection device and the combined wave control module; Figure 3 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0019] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] Optical transport network equipment channel security detection system based on quantum measurement, such as Figure 1 As shown, it includes an optical time-domain quantum detection device, application master control software, optical transmission network equipment and a multiplexing control module; Optical time-domain quantum detection device, based on quantum measurement, performs signal detection with high spatial resolution and large dynamic range, achieving high-precision perception of multi-dimensional parameters of optical fiber channels; Apply master control software to achieve device control, data processing and analysis based on artificial intelligence algorithms, and application layer communication; Optical transport network equipment exchanges information with application master control software through the management and control system to implement corresponding security policies; The combining control module combines the optical signal output by the optical time domain quantum detection device with the service signal output by the optical transmission network equipment, enters the optical fiber channel, and switches the detection line in a controlled manner.

[0021] ① Such as Figure 2 As shown, the optical time-domain quantum detection device includes a light source, a first attenuator, a circulator, a filter, a second attenuator, a single photon detector, and a signal driving and processing module; A light source generates a pump light signal to stimulate Rayleigh scattering signal / Brillouin scattering signal / Raman scattering signal; a first attenuator, controlling the intensity of the optical signal output by the optical time-domain quantum detection device to be within the safe operating range of the single-photon detector; The circulator couples the optical signal scattered back from the optical fiber channel to be tested into the detection optical path; The filter suppresses noise on optical transmission network line signals while supporting high transmittance of optical signals output by the optical time-domain quantum detection device, including Rayleigh scattering wavelengths, Brillouin scattering wavelengths, and Raman scattering wavelengths; The second attenuator realizes the synchronous attenuation control of the optical signal intensity detected by the optical time-domain quantum detection device and the signal noise of the optical transmission network line, so that the single photon detector is within the safe operating range; Single-photon detector, which can detect weak optical signals at the single-photon level and convert optical signals into electrical signals; The signal driving and processing module provides driving signals for the light source, the first attenuator, the second attenuator and the single-photon detector, and processes the detection signals.

[0022] 1) The light source is a 1.3μm high-repetition-rate (1.25GHz) narrow-pulse laser with adjustable pulse width in the picosecond to microsecond range. Since spatial resolution accuracy is inversely correlated with pulse width, and the fiber measurement range is inversely correlated with the repetition frequency of the optical signal, narrow pulse timing splicing is used to achieve low-repetition-rate wide-band pulse preparation. That is, assuming that the period of the laser outputting high-repetition-rate narrow pulses is t=1.25GHz, the required period of the low-repetition-rate wide-band pulses is T=1KHz, and the required duty cycle is 1%, then 1250 high-repetition-rate narrow pulses are transmitted within 1μs, and no light is emitted at other times. In this way, low-repetition-rate wide-band pulses are spliced within this time domain, enabling the optical time-domain quantum detection device to perform signal detection with high spatial resolution and a large dynamic range.

[0023] 2) The first attenuator and the second attenuator work together: When the optical time-domain quantum detection device is started to detect the environmental status, the attenuation degree of the first attenuator is the largest, and the attenuation degree of the second attenuator gradually decreases from large to small, so that the noise signal is gradually and controllably enhanced and enters the single-photon detector, confirming that the operating environment is safe; During the self-test of the optical time-domain quantum detection device, the attenuation of the first attenuator gradually decreases from high to low, and the attenuation of the second attenuator is the lowest, so that the optical signal gradually enters the single-photon detector, confirming that the laser light emission state is normal; When the signal-to-noise ratio of the detection signal is low, the attenuation degree of the second attenuator increases, which reduces the overall intensity of the optical signal and the noise signal. At the same time, the attenuation degree of the first attenuator decreases, which relatively enhances the optical signal. When the signal-to-noise ratio of the detection signal is high, the attenuation degree of the second attenuator is reduced, and at the same time the attenuation degree of the first attenuator is adjusted according to the strength of the detection signal; The first attenuator includes an electro-optic modulator, an acousto-optic modulator, or a MEMS attenuator; the single-photon detector operates in the near-infrared band, and the operating mode is a gated trigger mode or a free mode.

[0024] 3) The first attenuator uses distributed optical intensity control to gradually increase the light intensity over a certain distance in the fiber transmission direction. This compensates for the decrease in optical signal counts caused by fiber loss, avoids saturation of optical signal counts over short distances and low optical signal counts over long distances, and achieves dynamic range superposition through distributed optical intensity control: S11. Based on the fiber length, laser output intensity, and detector saturation count, evaluate the interval length of distributed light intensity control and the dynamic range limit DR-max of the single-photon detector. Assume that the total fiber length is L = 100 km and is divided into three segments: L1, L2, and L3 (the number of segments is determined based on parameter conditions in actual applications). The corresponding time intervals of the light reflection signal are T1, T2, and T3. S12, controlling the first attenuator so that the initial output light intensity of the L1 segment optical fiber is P0, obtaining a photon count and arrival time curve in the T1 period, and calculating the dynamic range DR1 of the T1 period; S13, controlling the first attenuator so that the initial output light intensity of the optical fiber L2 is close to P0, obtaining a curve of photon counts and arrival times in time period T2, and simultaneously shutting down the detector in time period T1, or discarding the counts due to count saturation, and calculating the dynamic range DR2 in time period T2; S14, controlling the first attenuator so that the initial output light intensity of the optical fiber section L3 is close to P0, obtaining a curve of photon counts and arrival times in time period T3, and simultaneously shutting down the detector in time periods T1 and T2, or discarding counts due to saturation, and calculating the dynamic range DR3 of time period T3; S15, splicing the photon count and arrival time curves in the time periods T1, T2, and T3 to form a complete photon count and arrival time curve within the length L, and drawing a loss-fiber length curve based on the fiber refractive index and ranging principle; Ideally, DR1=DR2=DR3=DR-max. Distributed light intensity control according to the above process can achieve a multiple increase in dynamic range after superposition.

[0025] 4) The optical time-domain quantum detection device is based on single-photon quantum measurement technology and high-precision spatial resolution technology to perform signal detection with high spatial resolution and a large dynamic range. The optical time-domain quantum detection device uses a variety of optical time-domain quantum measurement technologies, including those based on Rayleigh scattering signals, Brillouin scattering signals, and Raman scattering signals, to support the measurement and analysis of various operating parameters and safety risk parameters, including vibration, temperature, attenuation, breakpoints, bending, clamping, and spectrometry. Wherein, when there is more than one optical time-domain quantum detection device, a wavelength division multiplexing mode or a time division multiplexing mode is adopted for co-fiber transmission; 5) When the optical time-domain quantum detection device is measuring attenuation and breakpoint operating parameters and the test signal is a Rayleigh scattering signal, the filter operating wavelength is the same as the laser wavelength. At the same time, in order to suppress the signal noise of the optical transmission network line, the operating bandwidth is narrow, no more than 100 GHz, to improve the survivability of the device in noisy environments; When the optical time-domain quantum detection device performs attenuation and breakpoint operating parameter measurements and the test signal is a Brillouin scattering signal or a Raman scattering signal, the filter operating wavelength is correspondingly the Brillouin scattering wavelength or the Raman scattering wavelength.

[0026] ② The application main control software has the function of equipment control and parameter setting. The parameter setting includes the optical fiber measurement range, measurement time and measurement pulse width parameter setting; The application control software has data processing and analysis capabilities based on artificial intelligence algorithms, including convolutional neural networks (CNN), artificial neural networks (ANN), and K-nearest neighbor algorithms (KNN). It supports nonlinear supervised learning analysis using a combination of fiber channel detection data and optical transport network monitoring data. The application main control software has the function of displaying the optical fiber channel detection results and abnormal status alarms; The application master control software has optical transport network equipment communication functions, including information exchange such as alarm and detail reporting and detection command issuance. It also has security policies that allow optical transport network equipment to adaptively adjust to the application environment. The application master control software has an open protocol and can adapt to optical transport network equipment of different brands to achieve information exchange and resource sharing.

[0027] ③ Such as Figure 2 As shown, the combining control module is integrated into the optical time-domain quantum detection device or the optical transmission network equipment. The combining control module includes a 1*N (N is determined by the number of communication lines connected to the node) optical switch and combiner; 1*N optical switch, with the number of channels not less than the number of communication lines connecting the nodes, to switch between multiple communication lines connecting the nodes and implement roll call testing / periodic testing / alarm trigger start testing; The combiner, whose operating wavelengths cover the operating wavelengths of the optical time-domain quantum detection device and optical transport network equipment (i.e., O-band and C-band), combines the optical signal output by the optical time-domain quantum detection device with the service signal output by the optical transport network equipment and transmits them into the same optical fiber channel. This solves the demand for optical fiber resources for optical fiber channel detection, achieves inter-sensing integration, and reduces deployment costs. Among them, the combiner supports two-channel output, distributing the optical signal output by the optical time-domain quantum detection device and the service signal output by the optical transmission network equipment to the two optical fiber cores in the same optical cable respectively.

[0028] ④ The optical transport network equipment is the optical communication equipment of the OTN communication system, operating in the C band, with a bandwidth of 10 GHz, 4 output channels, and a power of 10 dBm.

[0029] Based on the above-disclosed optical transport network equipment channel security detection system based on quantum measurement, the technical solution of this application also discloses a method for detecting optical transport network equipment channel security based on quantum measurement, which is applied to the above-disclosed optical transport network equipment channel security detection system based on quantum measurement, such as Figure 3 As shown, it mainly includes quantum measurement, event analysis, business decision-making and algorithm training; Quantum measurement, which enables parameter measurement of optical fiber channels of optical transport network equipment; Event analysis and business decision-making: Using artificial intelligence algorithms to analyze event types and conduct security assessments on fiber channel detection results; Algorithm training analyzes system security parameter thresholds based on environmental evolution, adaptively adjusts security parameter thresholds, improves algorithm model accuracy, and provides fiber channel environmental trend assessment to achieve security risk early warning; The detailed process is as follows: S1. Check whether the control system receives a parameter abnormality alarm. If so, it switches to alarm link detection first and connects to the corresponding fiber channel to be tested after receiving a roll call test or periodic test command. S2. Start the quantum measurement process, trigger the single-photon detector, turn off the narrow pulse light source, and detect the background signal. If the detector count is abnormal, the main control software will determine the event type based on the abnormal data and report the device failure or line status abnormality details. If the fiber channel environment is normal and the detector count is normal, the next self-test will be carried out; S3: Trigger the light source and perform a self-test. If the light source status is abnormal, the device fault is reported. If the light source status is normal, the parameters are automatically set, spliced low-repetition-frequency wideband pulses are output, and distributed optical intensity control is performed to achieve characteristic value measurement of optical fiber channel operating parameters and safety risk parameters. S4. The main control software is used to continuously collect measured characteristic values and process and analyze the line detection data using artificial intelligence algorithms. Based on the analysis results, the line operation and safety status are determined. The training database is updated based on the currently collected data. If the line safety status is normal, the normal test results are reported in the roll call test, or optical time domain quantum detection is continuously performed in the periodic test. If the line safety status is abnormal, the event type is determined and an alarm is reported. The optical transport network equipment then regulates the equipment operation status based on the safety risk level. S5. After receiving the test results or alarm information, the optical transport network equipment executes the corresponding security policy. If there is no security risk on the line, business communication continues; if the event type is determined to be a device failure or abnormal line status, the equipment or line is notified for maintenance; if there is still a security risk on the line, business communication is terminated and the backup link communication is switched; if there is a risk of parameter quality deterioration on the line, the equipment or line is notified for maintenance or preventive inspection.

[0030] In the technical solution of this application, the security strategy includes: 1) Equipment security registration: When the optical time-domain quantum detection device is used for the first time, the main control software is used to report information including the module model and version number to the management and control system. After passing the authentication, the device obtains the online work permission; 2) High-light protection strategy: After the optical time-domain quantum detection device is put into operation, a self-test process is initiated to confirm that there is no risk of damage to the single-photon detector. Then, through light intensity control and measurement, the module is confirmed to be operating normally, and information including the module model and version number is reported to the management and control system. If the module is operating abnormally or the working environment poses a risk of damage to the single-photon detector, the module is reported as abnormal and operation is stopped. 3) Detection sensitivity improvement strategy: The optical time-domain quantum detection device uses narrow pulse timing splicing. By controlling the number of pulses sent in a single cycle and the number of vacuum pulses sent, it can achieve low repetition rate and adjustable width pulse preparation. This allows the measurement scheme to combine the advantages of high spatial resolution brought by high repetition rate narrow pulses with the wide dynamic range brought by low repetition rate wide pulses. 4) Dynamic range improvement strategy: The optical time-domain quantum detection device uses distributed light intensity control to control the step-wise increase of light intensity in the direction of optical fiber transmission to compensate for signal loss caused by continuous fiber loss, avoid saturation of optical signal counts over short distances and low optical signal counts over long distances, and achieve the dynamic range of conventional measurements within a single area. Through distributed light intensity control, the dynamic range of multiple intervals can be superimposed, thereby effectively improving the dynamic range of the system; 5) Event type determination strategy: Event types include end, reflection, attenuation, vibration, and temperature. End events, reflection events, large attenuation events, large dynamic vibration events, and temperature change events can be directly detected using an optical time-domain quantum detection device. For small loss events such as breakpoints, splitting, bending, and clamping, as well as small vibration and temperature change events, an artificial intelligence algorithm is used to perform nonlinear supervised learning analysis using combined data to accurately determine the event type. 6) Optical time-domain quantum detection device trigger mechanism: supports automatic startup at power-up or parameter anomaly triggering, including triggering when events such as loss anomalies and bit error rate anomalies are reported. In integrated quantum key distribution encryption communication systems, it supports instant triggering based on abnormal phenomena, including jumps in the bit error rate of the quantum key distribution system, to achieve parameter anomaly analysis and location. 7) Working Mode: Supports manual scanning and automatic scanning. In manual scanning mode, commands are issued through the management and control system to control the start of the target line optical time domain quantum detection device. In automatic scanning mode, it supports parameter abnormality triggering, as well as long-term online or timed periodic detection of single channels. For one-to-many communication nodes, it supports multi-channel optical switch switching to achieve multi-line patrol testing, and reports abnormal events through the management and control system. 8) Alarm prompt: Based on quantum measurement and artificial intelligence analysis, if the system has performance anomalies or security risks, the main control software will report the alarm information and abnormal information details to the management and control system and display them on the interface.

[0031] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A quantum measurement-based optical transport network equipment channel security detection system, characterized by: It includes optical time-domain quantum detection device, application master control software, optical transmission network equipment and multiplexing control module; Optical time-domain quantum detection device, based on quantum measurement, performs signal detection with high spatial resolution and large dynamic range, achieving high-precision perception of multi-dimensional parameters of optical fiber channels; Apply master control software to achieve device control, data processing and analysis based on artificial intelligence algorithms, and application layer communication; Optical transport network equipment exchanges information with application master control software through the management and control system to implement corresponding security policies; The combining control module combines the optical signal output by the optical time domain quantum detection device with the service signal output by the optical transmission network equipment, enters the optical fiber channel, and switches the detection line in a controlled manner.

2. The optical transport network equipment channel security detection system based on quantum measurement according to claim 1, characterized in that: The optical time-domain quantum detection device includes a light source, a first attenuator, a circulator, a filter, a second attenuator, a single-photon detector, and a signal driving and processing module; A light source generates a pump light signal to stimulate Rayleigh scattering signal / Brillouin scattering signal / Raman scattering signal; a first attenuator, controlling the intensity of the optical signal output by the optical time-domain quantum detection device to be within the safe operating range of the single-photon detector; The circulator couples the optical signal scattered back from the optical fiber channel to be tested into the detection optical path; The filter suppresses noise on optical transmission network line signals while supporting high transmittance of optical signals output by the optical time-domain quantum detection device, including Rayleigh scattering wavelengths, Brillouin scattering wavelengths, and Raman scattering wavelengths; The second attenuator realizes the synchronous attenuation control of the optical signal intensity detected by the optical time-domain quantum detection device and the signal noise of the optical transmission network line, so that the single-photon detector is within the safe operating range; Single-photon detectors can detect weak optical signals at the single-photon level and convert optical signals into electrical signals; The signal driving and processing module provides driving signals for the light source, the first attenuator, the second attenuator and the single-photon detector, and processes the detection signals.

3. The optical transport network equipment channel security detection system based on quantum measurement according to claim 2, characterized in that: The light source is a narrow pulse laser with adjustable pulse width in the range of picoseconds to microseconds. Since the spatial resolution accuracy is inversely correlated with the pulse width, and the optical fiber measurement range is inversely correlated with the repetition frequency of the optical signal, a narrow pulse time sequence splicing method is used to achieve low repetition rate and wide pulse preparation. That is, assuming that the period of the laser outputting high repetition rate narrow pulses is t, the required period of the low repetition rate and wide pulses is T, and the required duty cycle is n%, then within the T*n% time, T*n% / t high repetition rate narrow pulses are sent, and no light is emitted at the time T*(1-n%), so as to obtain low repetition rate and wide pulses by splicing within this time domain, so that the optical time domain quantum detection device can perform signal detection with high spatial resolution and a large dynamic range.

4. The optical transport network equipment channel security detection system based on quantum measurement according to claim 2, characterized in that: The first attenuator works in conjunction with the second attenuator: When the optical time-domain quantum detection device is started to detect the environmental status, the attenuation degree of the first attenuator is the largest, and the attenuation degree of the second attenuator gradually decreases from large to small, so that the noise signal is gradually and controllably enhanced and enters the single-photon detector, confirming that the operating environment is safe; During the self-test of the optical time-domain quantum detection device, the attenuation of the first attenuator gradually decreases from high to low, and the attenuation of the second attenuator is the lowest, so that the optical signal gradually enters the single-photon detector, confirming that the laser light emission state is normal; When the signal-to-noise ratio of the detection signal is low, the attenuation degree of the second attenuator increases, which reduces the overall intensity of the optical signal and the noise signal. At the same time, the attenuation degree of the first attenuator decreases, which relatively enhances the optical signal. When the signal-to-noise ratio of the detection signal is high, the attenuation degree of the second attenuator is reduced, and at the same time the attenuation degree of the first attenuator is adjusted according to the strength of the detection signal; The first attenuator includes an electro-optic modulator, an acousto-optic modulator, or a MEMS attenuator; the single-photon detector operates in the near-infrared band, and the operating mode is a gated trigger mode or a free mode.

5. The optical transport network equipment channel security detection system based on quantum measurement according to claim 4, characterized in that: The first attenuator uses distributed optical intensity control to gradually increase the light intensity over a certain distance in the optical fiber transmission direction. This compensates for the reduction in optical signal counts caused by optical fiber loss, avoids saturation of optical signal counts over short distances and low optical signal counts over long distances, and achieves dynamic range superposition through distributed optical intensity control. S11. Evaluate the interval length of distributed light intensity control and the dynamic range limit DR-max of the single-photon detector based on the fiber length, laser output intensity, and detector saturation count. Suppose the total fiber length is L, which is divided into three segments: L1, L2, and L3. The corresponding time intervals of the light reflection signal are T1, T2, and T3. S12, controlling the first attenuator so that the initial output light intensity of the L1 segment optical fiber is P0, obtaining a photon count and arrival time curve in the T1 period, and calculating the dynamic range DR1 of the T1 period; S13, controlling the first attenuator so that the initial output light intensity of the optical fiber L2 is close to P0, obtaining a curve of photon counts and arrival times in time period T2, and simultaneously shutting down the detector in time period T1, or discarding the counts due to count saturation, and calculating the dynamic range DR2 in time period T2; S14, controlling the first attenuator so that the initial output light intensity of the optical fiber section L3 is close to P0, obtaining a curve of photon counts and arrival times in time period T3, and simultaneously shutting down the detector in time periods T1 and T2, or discarding counts due to saturation, and calculating the dynamic range DR3 of time period T3; S15, splicing the photon count and arrival time curves in the time periods T1, T2, and T3 to form a complete photon count and arrival time curve within the length L, and drawing a loss-fiber length curve based on the fiber refractive index and ranging principle; Ideally, DR1=DR2=DR3=DR-max. Distributed light intensity control according to the above process can achieve a multiple increase in dynamic range after superposition.

6. The optical transport network equipment channel security detection system based on quantum measurement according to claim 2, characterized in that: The optical time-domain quantum detection device is based on single-photon quantum measurement technology and high-precision spatial resolution technology to perform signal detection with high spatial resolution and large dynamic range. The optical time-domain quantum detection device adopts a variety of optical time-domain quantum measurement technologies including Rayleigh scattering signals, Brillouin scattering signals, and Raman scattering signals, and supports the measurement and analysis of a variety of working parameters and safety risk parameters including vibration, temperature, attenuation, breakpoint, bending, clamping, and spectrometry. When the optical time-domain quantum detection device is measuring attenuation and breakpoint parameters and the test signal is a Rayleigh scattering signal, the filter operating wavelength is the same as the laser wavelength. To suppress optical transmission network line noise, the operating bandwidth is narrow, no more than 100 GHz, to improve the survivability of the device in noisy environments. When the optical time-domain quantum detection device performs attenuation and breakpoint working parameter measurements and the test signal is a Brillouin scattering signal or a Raman scattering signal, the filter operating wavelength is correspondingly the Brillouin scattering wavelength or the Raman scattering wavelength; When there is more than one optical time-domain quantum detection device, a wavelength division multiplexing mode or a time division multiplexing mode is adopted for co-fiber transmission.

7. The optical transport network equipment channel security detection system based on quantum measurement according to claim 1, characterized in that: The application main control software has equipment control functions and parameter setting functions, and the parameter settings include optical fiber measurement range, measurement time, and measurement pulse width parameter settings; The application master control software has data processing and analysis functions based on artificial intelligence algorithms, including convolutional neural networks (CNN), artificial neural networks (ANN), and K-nearest neighbor algorithms (KNN), and supports nonlinear supervised learning analysis using a combination of fiber channel detection data and optical transport network monitoring data; The application master control software has the function of displaying the optical fiber channel detection results and abnormal state alarm display; The application master control software has optical transport network equipment communication functions, including information exchange such as alarm and detail reporting and detection command issuance, and also has security policies for adaptive adjustment of optical transport network equipment in the application environment; The application master control software has an open protocol and can be adapted to optical transport network equipment of different brands to achieve information intercommunication and resource sharing.

8. The optical transport network equipment channel security detection system based on quantum measurement according to claim 1, characterized in that: The wave combining control module is integrated into an optical time domain quantum detection device or an optical transmission network device, and the wave combining control module includes a 1*N optical switch and a combiner; 1*N optical switch, with the number of channels not less than the number of communication lines connecting the nodes, to switch between multiple communication lines connecting the nodes and implement roll call testing / periodic testing / alarm trigger start testing; The combiner, whose operating wavelength covers the operating wavelength of the optical time-domain quantum detection device and the optical transport network equipment, combines the optical signal output by the optical time-domain quantum detection device with the service signal output by the optical transport network equipment and transmits them into the same optical fiber channel. This solves the demand for optical fiber resources for optical fiber channel detection, achieves inter-sensing integration, and reduces deployment costs. Among them, the combiner supports two-channel output, distributing the optical signal output by the optical time-domain quantum detection device and the service signal output by the optical transmission network equipment to the two optical fiber cores in the same optical cable respectively.

9. A method for detecting channel security of optical transport network equipment based on quantum measurement, applied to the system for detecting channel security of optical transport network equipment based on quantum measurement according to claim 1, characterized in that: Mainly includes quantum measurement, event analysis, business decision-making and algorithm training; Quantum measurement, which enables parameter measurement of optical fiber channels of optical transport network equipment; Event analysis and business decision-making: Using artificial intelligence algorithms to analyze event types and conduct security assessments on fiber channel detection results; Algorithm training analyzes system security parameter thresholds based on environmental evolution, adaptively adjusts security parameter thresholds, improves algorithm model accuracy, and provides fiber channel environmental trend assessment to achieve security risk early warning; The detailed process is as follows: S1. Check whether the control system receives a parameter abnormality alarm. If so, it switches to alarm link detection first and connects to the corresponding fiber channel to be tested after receiving a roll call test or periodic test command. S2. Start the quantum measurement process, trigger the single-photon detector, turn off the narrow pulse light source, and detect the background signal. If the detector count is abnormal, the main control software will determine the event type based on the abnormal data and report the device failure or line status abnormality details. If the fiber channel environment is normal and the detector count is normal, the next self-test will be carried out; S3: Trigger the light source and perform a self-test. If the light source status is abnormal, the device fault is reported. If the light source status is normal, the parameters are automatically set, spliced low-repetition-frequency wideband pulses are output, and distributed optical intensity control is performed to achieve characteristic value measurement of optical fiber channel operating parameters and safety risk parameters. S4. Apply the main control software to continuously collect measured characteristic values and use artificial intelligence algorithms to process and analyze the line detection data. Based on the analysis results, the line operation and safety status are judged and evaluated. The training database is updated based on the currently collected data. If the line safety status is normal, the normal test results are reported in the roll call test, or optical time domain quantum detection is continuously performed in the periodic test. If the line security status is abnormal, the event type is determined and an alarm is reported. The optical transport network equipment adjusts the equipment operation status according to the security risk level. S5. After receiving the test results or alarm information, the optical transport network equipment executes the corresponding security policy. If there is no security risk on the line, business communication continues; if the event type is determined to be a device failure or abnormal line status, the equipment or line is notified for maintenance; if there is still a security risk on the line, business communication is terminated and the backup link communication is switched; if there is a risk of parameter quality deterioration on the line, the equipment or line is notified for maintenance or preventive inspection.

10. The method for detecting channel security of optical transport network equipment based on quantum measurement according to claim 9, characterized in that: The security policy includes: 1) Equipment security registration: When the optical time-domain quantum detection device is used for the first time, the main control software is used to report information including the module model and version number to the management and control system. After passing the authentication, the device obtains the online work permission; 2) High-light protection strategy: After the optical time-domain quantum detection device is put into operation, a self-test process is initiated to confirm that there is no risk of damage to the single-photon detector. Then, through light intensity control and measurement, the module is confirmed to be operating normally, and information including the module model and version number is reported to the management and control system. If the module is operating abnormally or the working environment poses a risk of damage to the single-photon detector, the module is reported as abnormal and operation is stopped. 3) Detection sensitivity improvement strategy: The optical time-domain quantum detection device uses narrow pulse timing splicing. By controlling the number of pulses sent in a single cycle and the number of vacuum pulses sent, it can achieve low repetition rate and adjustable width pulse preparation. This allows the measurement scheme to combine the advantages of high spatial resolution brought by high repetition rate narrow pulses with the wide dynamic range brought by low repetition rate wide pulses. 4) Dynamic range improvement strategy: The optical time-domain quantum detection device uses distributed light intensity control to control the step-wise increase of light intensity in the direction of optical fiber transmission to compensate for signal loss caused by continuous fiber loss, avoid saturation of optical signal counts over short distances and low optical signal counts over long distances, and achieve the dynamic range of conventional measurements within a single area. Through distributed light intensity control, the dynamic range of multiple intervals can be superimposed, thereby effectively improving the dynamic range of the system; 5) Event type determination strategy: Event types include end, reflection, attenuation, vibration, and temperature. End events, reflection events, large attenuation events, large dynamic vibration events, and temperature change events can be directly detected using an optical time-domain quantum detection device. For small loss events such as breakpoints, splitting, bending, and clamping, as well as small vibration and temperature change events, an artificial intelligence algorithm is used to perform nonlinear supervised learning analysis using combined data to accurately determine the event type. 6) Optical time-domain quantum detection device trigger mechanism: supports automatic startup at power-up or parameter anomaly triggering, including triggering when events such as loss anomalies and bit error rate anomalies are reported. In integrated quantum key distribution encryption communication systems, it supports instant triggering based on abnormal phenomena, including jumps in the bit error rate of the quantum key distribution system, to achieve parameter anomaly analysis and location. 7) Working Mode: Supports manual scanning and automatic scanning. In manual scanning mode, commands are issued through the management and control system to control the start of the target line optical time domain quantum detection device. In automatic scanning mode, it supports parameter abnormality triggering, as well as long-term online or timed periodic detection of single channels. For one-to-many communication nodes, it supports multi-channel optical switch switching to achieve multi-line patrol testing, and reports abnormal events through the management and control system. 8) Alarm prompt: Based on quantum measurement and artificial intelligence analysis, if the system has performance anomalies or security risks, the main control software will report the alarm information and abnormal information details to the management and control system and display them on the interface.

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