Fiber Optical Cable monitoring device on the network

Abstract

The present invention relates to a linear and star-shaped optical line monitoring device as well as a ring network. The optical line monitoring device of a ring network comprises a central office terminal (100) equipped with a first L2 switch (110), and a plurality of remote terminals (201 to 20n) equipped with a second L2 switch (210) located on an optical line configured in a ring shape from the central office terminal (100) to the end point. The device is composed of an OTDR module (Optical time Domain Reflectormeter module) (120) connected to the first L2 switch (110) of the central office terminal (100) to send measurement light for optical line monitoring and detect fault points on the optical line using the reflected wave returning, and a second WDM (wavelength-division multipexing) filter (222) connected to the second L2 switch (210) of the plurality of terminals (101 to 20n) to pass the measurement light sent from the OTDR module (120).

Description

Technology Field

[0001] The present invention relates to a linear and star-type optical fiber monitoring device as well as a ring network, and more specifically, to a linear and star-type optical fiber monitoring device that is applied to an operating ring network to check (monitor) for abnormalities in the optical fiber and to enable rapid response to network maintenance and service. Background Technology

[0002] In current network systems, wired communication networks are being converted to optical cables from the backbone to the subscriber network. Due to the rapid increase in optical cables and the diverse and complex installation structures of optical line networks, efficient network maintenance is emerging as a critical factor.

[0003] Optical network systems like the one described above include the Linear Type, in which remote terminals (RTs) are connected to a central main network switch (COT); the Ring Type, in which the ends are connected to form a circle while the main network switch (COT) is in the center; and the Star Type, in which remote terminals (RTs) are connected radially based on the main network switch (COT).

[0004] As such, an automatic optical line monitoring and management system is adopted and used as a means for rapid and efficient maintenance by monitoring damage and failures in the optical lines constituting the optical network.

[0005] This automatic optical fiber monitoring system performs monitoring by sequentially selecting specific optical cores and automatically scheduling them without affecting the communication services of the operating optical fibers. By measuring the backscattered waveforms of the optical fibers, it performs distance search to locate the cause and location of changes in optical loss caused by physical deformation or environmental influences, and is configured to enable operators to quickly perform restoration tasks using the fault location information of the optical fibers.

[0006] The above-described optical fiber automatic monitoring system utilizes a centralized monitoring method in which an optical fiber monitoring device is installed at the center and a single monitoring device monitors the entire monitoring section. By applying it to wide-area or medium-range optical networks, recovery is possible through rapid identification of the cause and location of failures, and operational information of the optical fibers can be managed systematically and efficiently, thereby maximizing the survivability of the optical fibers.

[0007] However, since establishing such conventional automatic optical fiber monitoring systems requires combining numerous pieces of equipment, devices, and facilities to form a large-scale system, the installation and operating costs are considerably high, which limits their application to all optical fibers constituting a network.

[0008] In other words, as mentioned earlier, while it may be efficient when applied to wide-area and mid-range optical networks, for small-scale networks, efficiency drops significantly because building an automatic optical line monitoring system costs several times more than the total cost of configuring the optical network.

[0009] For this reason, optical lines constituting small-scale optical networks are currently being operated without a monitoring system to monitor for damage or abnormalities, and when an optical line failure occurs during operation, the presence or absence of abnormalities in the optical line is checked using a separate inspection device such as an ODTR (Optical time Domain Reflector Meter) that is not connected to the optical network.

[0010] When verifying the presence or absence of abnormalities in optical fibers using separately provided inspection equipment as described above, the cause and location of the failure must rely on the operator's proficiency and intellectual judgment; consequently, there is a problem in that maintenance efficiency is significantly lower compared to automatic monitoring by the system. Prior art literature

[0011] Patent No. 10-2158867 (Registration announced Sep. 22, 2020) Patent No. 10-2146295 (Registration announced Aug. 20, 2020) Patent No. 10-2243559 (Registration announced Apr. 22, 2021) The problem to be solved

[0012] The present invention, which aims to solve the problems of the prior art described above, provides a linear and star-type optical fiber monitoring device as well as a ring network, which is applied to an operating ring network to automatically check (monitor) for abnormalities in optical fibers and enable rapid response to network maintenance and service. means of solving the problem

[0013] The above-mentioned objective is achieved by a linear and star-shaped optical line monitoring device as well as a ring network, comprising a central office terminal equipped with a first L2 switch and a plurality of field terminals equipped with a second L2 switch located on an optical line configured in a ring shape from the central office terminal to the start and end points, wherein the device comprises: an OTDR module (Optical time Domain Reflectormeter module) connected to the first L2 switch of the central office terminal to send measurement light for optical line monitoring and detect fault points of the optical line using the reflected waves returning; and a second WDM (wavelength-division multipexing) filter connected to the second L2 switch of the plurality of terminals to pass the measurement light sent from the OTDR module.

[0014] According to one aspect of the present invention, the OTDR module or the second WDM filter is characterized by being configured as an internal or external type.

[0015] According to another aspect of the present invention, the OTDR module is characterized by sending a measurement light in one direction from a start or end point to a light path and measuring a fault point using a reflected wave that is reflected back.

[0016] According to another aspect of the present invention, the OTDR module is characterized by sending measurement light in both directions from the start and end points to optical fiber paths and measuring the fault point using the reflected wave that is reflected back.

[0017] According to another aspect of the present invention, the OTDR module is characterized by measuring the fault point of the optical fiber by sending measurement light having different wavelengths in one direction or both directions of the optical fiber and measuring the reflected waves when the optical fiber is a 1-core WDM.

[0018] According to another aspect of the present invention, the OTDR module is characterized by measuring the fault point of the optical fiber line by sending two specific wavelengths to the transmitting and receiving cores respectively and measuring the reflected waves, because in the case of a 2-core duplex optical fiber line, the transmitting and receiving cores communicate separately, so if either of the two cores fails, communication becomes impossible and both the transmitting and receiving cores must be checked. According to another aspect of the present invention, the OTDR module is characterized by being composed of: an OTDR that sends a measurement light for optical fiber line monitoring and detects the fault point of the optical fiber line using the reflected waves returning; and a first WDM (wavelength-division multipexing) filter connected to the OTDR and the first L2 switch to pass specific wavelengths.

[0019] According to another aspect of the present invention, the first and second L2 switches are characterized by having first and second optical bypass connectors that connect the second L2 switch adjacent to the first WDM filter of the OTDR module, or another second L2 switch adjacent to one of the second L2 switches, and allow light to pass through.

[0020] According to another aspect of the present invention, the first and second L2 switches are characterized by having first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) of 1-core WDM that are connected to the first WDM filter or the second WDM filter of the OTDR module and provide wavelengths of 1310 nm and 1500 nm.

[0021] According to another aspect of the present invention, the first and second L2 switches are characterized by having first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) of 2-core duplex that are connected to the first WDM filter or the second WDM filter of the OTDR module and provide wavelengths other than 1625 nm and 1650 nm wavelengths, such as 1310 nm and 1500 nm wavelengths.

[0022] According to another aspect of the present invention, a dedicated Element Management System (EMS) can be operated externally or internally, which is connected to the first L2 switch of the central processing terminal via TCP / IP or I2C communication and displays the location of the optical fiber line where the problem occurred as a graph when the optical fiber line problem occurs.

[0023] According to another aspect of the present invention, an optical module is placed on an optical line connecting the central processing terminal and the plurality of terminals, or on an optical line connecting the plurality of terminals, according to the length of the optical line or the environment of the ring network formed by the optical line, thereby extending the monitoring distance of the optical line. Effects of the invention

[0024] According to the present invention, by placing an OTDR module in a central processing terminal and arranging WDM filters in each terminal at the site connected in a ring shape at both ends of the central processing terminal, it is possible to check (monitor) the presence or absence of abnormalities in the ring network and linear star optical fiber line in real time, thereby enabling rapid response to network maintenance and service. Brief explanation of the drawing

[0025] FIG. 1 is a drawing showing an optical fiber monitoring device of a ring network according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a 1-core WDM (wavelength-division multipexing) to which an optical line monitoring device of a ring network according to an embodiment of the present invention is applied. FIG. 3 is a configuration diagram of a 2-core duplex to which an optical fiber monitoring device of a ring network according to an embodiment of the present invention is applied. Specific details for implementing the invention

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail together with the illustrative drawings.

[0027] FIG. 1 is a drawing showing an optical fiber monitoring device of a ring network according to an embodiment of the present invention.

[0028] According to FIG. 1, the optical line monitoring device of a ring network according to an embodiment of the present invention comprises a central processing terminal (100) equipped with a first L2 switch (110), and a plurality of field terminals (201 to 20n) equipped with a second L2 switch (210) located on an optical line configured in a ring shape from the central processing terminal (100) to the end point, wherein the device comprises an OTDR module (120) connected to the first L2 switch (110) of the central processing terminal (100) to send measurement light for optical line monitoring and detect a fault point of the optical line using a reflected wave returning from it, and a second WDM filter (222) connected to the second L2 switch (210) of the plurality of terminals (101 to 20n) to pass the measurement light sent from the OTDR module (120).

[0029] In the above, the OTDR module (120) or the second WDM filter (222) may be configured as an internal or external type.

[0030] In the above, the OTDR module (120) can measure the fault point by sending a measurement light in one direction from a start or end point and measuring the fault point with the reflected wave that is reflected back, or by sending a measurement light in both directions from a start and end point and measuring the fault point with the reflected wave that is reflected back.

[0031] That is, when the optical fiber path is a 1-core WDM, the OTDR module (120) can measure the fault point of the optical fiber path by sending measurement light with different wavelengths in one direction or both directions of the optical fiber path and measuring the reflected waves, and when the optical fiber path is a 2-core duplex, it can measure the fault point of the optical fiber path by sending measurement light with two specific wavelengths in one direction of the optical fiber path and measuring the reflected waves.

[0032] Additionally, the OTDR module (120) is composed of an OTDR (121) that sends a measurement light for monitoring the optical line and detects fault points in the optical line using the reflected wave returning, and a first WDM (wavelength-division multipexing) filter (122) that is connected to the OTDR (121) and the first L2 switch (110) and passes a specific wavelength.

[0033] Additionally, the first and second L2 switches (110) (210) may be equipped with first and second optical bypass connectors (112) (212) that allow light to pass through, which connect the second L2 switch (210) adjacent to the first WDM filter (122) of the OTDR module (120), or another second L2 switch (210) adjacent to one second L2 switch (210).

[0034] Additionally, the first and second L2 switches (110) (210) may be connected to the first WDM filter (122) or the second WDM filter (222) of the OTDR module (120) and may be equipped with first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) (111) (211) of 1-core WDM that provide wavelengths of 1310 nm and 1500 nm.

[0035] Additionally, the first and second L2 switches (110) (210) may be equipped with first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) (111) (211) of 2-core duplex that are connected to the first WDM filter (122) or the second WDM filter (222) of the OTDR module (120) to provide a wavelength of 1310 nm.

[0036] In addition, the embodiment can extend the monitoring distance of the optical line by placing optical modules on the optical line connecting the central processing terminal (100) and a plurality of terminals (201 to 20n) or on the optical line connecting the plurality of terminals (201 to 20n) according to the length of the optical line or the environment of the ring network formed by the optical line.

[0038] FIG. 2 is a configuration diagram of a 1-core WDM (wavelength-division multipexing) to which an optical line monitoring device of a ring network according to the present invention is applied.

[0039] According to FIG. 2, the 1-core WDM to which an embodiment of the present invention is applied comprises a central processing terminal (100) equipped with a first L2 switch (110) corresponding to a 1-core, and a plurality of field terminals (201 to 20n) equipped with a second L2 switch (210) corresponding to a 1-core located on a 1-core optical path configured in a ring shape from the central processing terminal (100) to the end point, wherein the OTDR module (120) is connected to the first L2 switch (110) of the central processing terminal (100) to send measurement light for monitoring the 1-core optical path and detects a fault point of the optical path by the reflected wave returning, and a second WDM filter (222) connected to the second L2 switch (210) of the plurality of terminals (101 to 20n) to pass the measurement light sent from the OTDR module (120).

[0040] In the above, when the total length of the network connecting the central processing terminal (100) and the multiple terminals (101 to 20n) is less than 100 km, the OTDR module (120) measures the fault point of the optical line by sending a measurement light in one direction from the start or end point to the optical line and measuring the reflected wave, and when the total length of the network connecting the central processing terminal (100) and the multiple terminals (101 to 20n) is 100 km or more, it measures the fault point of the optical line by sending a measurement light of different wavelengths in both directions from the start and end points to the optical line and measuring the reflected wave.

[0041] Here, since the optical path is a 1-core WDM, the OTDR module (120) can measure the fault point of the optical path by sending measurement light of different wavelengths of 1310 nm and 1500 nm in one direction or both directions of the optical path and measuring the reflected waves.

[0042] Above, the OTDR module (120) is composed of an OTDR (121) that sends measurement light for optical line monitoring and detects fault points in the optical line with the reflected wave returning, and a first WDM (wavelength-division multipexing) filter (122) connected to the OTDR (121) and the first L2 switch (110) to pass 1310nm and 1500nm wavelengths.

[0043] Additionally, the first and second L2 switches (110) (210) may be equipped with first and second optical bypass connectors (112) (212) that allow light to pass through, and may be equipped with first and second SFP-GBICs (111) (211) of 1-core WDM that are connected to the first WDM filter (122) or the second WDM filter (222) of the OTDR module (120) to provide wavelengths of 1310 nm and 1500 nm.

[0044] In addition, the present invention is equipped with a dedicated EMS (Element Management System) (300) that is connected to the first L2 switch (110) of the central processing terminal (100) via TCP / IP or I2C communication and displays the location of the optical fiber line where the problem occurred as a graph when the optical fiber line problem occurs, and the dedicated EMS (300) can be operated as an external or internal type.

[0045] In addition, the present invention can extend the monitoring distance of an optical line by additionally arranging optical modules on an optical line connecting a central processing terminal (100) and a plurality of terminals (201 to 20n) or on an optical line connecting a plurality of terminals (201 to 20n), depending on the length of the optical line or the environment of the ring network formed by the optical line.

[0047] FIG. 3 is a configuration diagram of a 2-core duplex to which the optical fiber monitoring device of a ring network according to the present invention is applied.

[0048] According to FIG. 3, the 2-core duplex to which an embodiment of the present invention is applied comprises a central processing terminal (100) equipped with a first L2 switch (110) corresponding to the 2 cores, and a plurality of field terminals (201 to 20n) equipped with a second L2 switch (210) corresponding to the 2 cores located on a 2-core optical path configured in a ring shape from the central processing terminal (100) to the end point, and an OTDR module (120) connected to the first L2 switch (110) of the central processing terminal (100) to send measurement light for monitoring the 2-core optical path and detect a fault point of the optical path by the reflected wave returning, and a second WDM filter (222) connected to the second L2 switch (210) of the plurality of terminals (101 to 20n) to pass the measurement light sent from the OTDR module (120).

[0049] In the above, when the total length of the network connecting the central processing terminal (100) and the multiple terminals (101 to 20n) is less than 100 km, the OTDR module (120) measures the fault point of the optical line by sending a measurement light in one direction from the start or end point to the optical line and measuring the reflected wave, and when the total length of the network connecting the central processing terminal (100) and the multiple terminals (101 to 20n) is 100 km or more, it measures the fault point of the optical line by sending a measurement light of different wavelengths in both directions from the start and end points to the optical line and measuring the reflected wave.

[0050] Here, since the optical path of the OTDR module (120) is a 2-core duplex, it can measure the fault point of the optical path by sending measurement light of wavelengths of 1625 nm and 1650 nm in one direction of the optical path and measuring the reflected waves.

[0051] Above, the OTDR module (120) is composed of an OTDR (121) that sends measurement light for optical line monitoring and detects fault points in the optical line with the reflected wave returning, and a first WDM (wavelength-division multipexing) filter (122) connected to the OTDR (121) and the first L2 switch (110) to pass a wavelength of 1310 nm.

[0052] Additionally, the first and second L2 switches (110) (210) may be equipped with first and second optical bypass connectors (112) (212) that allow light to pass through, and may be equipped with first and second SFP-GBICs (111) (211) of 2-core duplex that are connected to the first WDM filter (122) of the OTDR module (120) and the second L2 switch (210) adjacent to the first L2 switch (210) and the second L2 switch (210) adjacent to the first WDM filter (122) of the OTDR module (120) and provide a wavelength of 1310 nm.

[0053] In addition, the present invention is equipped with a dedicated EMS (Element Management System) (300) that is connected to the first L2 switch (110) of the central processing terminal (100) via TCP / IP or I2C communication and displays the location of the optical fiber line where the problem occurred as a graph when the optical fiber line problem occurs, and the dedicated EMS (300) can be operated as an external or internal type.

[0054] In addition, the present invention can extend the monitoring distance of an optical line by additionally arranging optical modules on an optical line connecting a central processing terminal (100) and a plurality of terminals (201 to 20n) or on an optical line connecting a plurality of terminals (201 to 20n), depending on the length of the optical line or the environment of the ring network formed by the optical line.

[0055] In the above embodiments, an optical fiber monitoring device in a ring network was described as an example; however, the present invention is not limited thereto and can be applied not only to ring networks but also to linear, star-type, and other optical fibers.

[0056] The present invention is not limited to the above embodiments, and various modifications and variations are possible from this description by those skilled in the art. Accordingly, the concept of the present invention should be understood only by the claims set forth below, and all equivalent or analogous variations thereof shall be considered to fall within the scope of the concept of the present invention. Explanation of the symbols

[0057] 100: Central Processing Terminal 110: 1st L2 Switch 111, 211: 1st and 2nd SFP-GBICs 122, 222: 1st and 2nd WDM Filters 112, 212: 1st and 2nd Optical Bypass Connectors 120: OTDR Module 121: OTDR 210: 2nd L2 Switch 201~20n: Terminals 300: Dedicated EMS

Claims

Claim 1 In a ring network as well as a linear and star-shaped optical line monitoring device comprising a central office terminal (100) equipped with a first L2 switch (110) and a plurality of field terminals (201-20n) equipped with a second L2 switch (210) located on an optical line configured in a ring shape from the central office terminal (100) to the end points, the device comprises an OTDR (121) that detects a fault point on the optical line by sending a measurement light for optical line monitoring and a reflected wave returning from it, and a first WDM (wavelength-division multipexing) filter (122) connected to the OTDR (121) and the first L2 switch (110) to pass a specific wavelength, wherein the OTDR module (Optical time Domain) connected to the first L2 switch (110) of the central office terminal (100) sends a measurement light for optical line monitoring and detects a fault point on the optical line by a reflected wave returning from it. A linear and star-shaped optical line monitoring device as well as a ring network, comprising: a reflector meter module (120); a second WDM (wavelength-division multipexing) filter (222) connected to the second L2 switch (210) of the plurality of terminals (101 to 20n) to pass measurement light sent from the OTDR module (120); and an optical module disposed on an optical line connecting the central processing terminal (100) and the plurality of terminals (201 to 20n) or on an optical line connecting the plurality of terminals (201 to 20n) to extend the monitoring distance of the optical line according to the length of the optical line or the environment of the ring network formed by the optical line. Claim 2 A linear and star optical line monitoring device as well as a ring network, characterized in that, in claim 1, the OTDR module (120) or the second WDM filter (222) is configured as an internal or external type. Claim 3 In claim 1, the OTDR module (120) is characterized by sending a measurement light in one direction from a start or end point to a light path and measuring a fault point with a reflected wave that is reflected back, as well as a ring network, linear, and star-shaped optical path monitoring device. Claim 4 In claim 1, the OTDR module (120) is characterized by sending measurement light in both directions from the start and end points to the optical fiber paths and measuring the fault point using the reflected wave that is reflected back, as well as a ring network and linear and star-shaped optical fiber path monitoring device. Claim 5 A network optical line monitoring device according to claim 1, wherein the OTDR module (120) is characterized by measuring the fault point of the optical line by sending measurement light having different wavelengths in one direction or both directions of the optical line and measuring the reflected waves when the optical line is a 1-core WDM. Claim 6 In claim 1, the OTDR module (120) is characterized by measuring the fault point of the optical line by sending two specific wavelengths of measurement light in each direction of the optical line and measuring the reflected waves when the optical line is a 2-core duplex, and is a linear and star-type optical line monitoring device as well as a ring network. Claim 7 delete Claim 8 In claim 1, the first and second L2 switches (110) (210) are characterized by having first and second optical bypass connectors (112) (212) that allow light to pass through, which connect the second L2 switch (210) adjacent to the first WDM filter (122) of the OTDR module (120), or another second L2 switch (210) adjacent to one of the second L2 switches (210). This describes a linear and star-shaped optical line monitoring device as well as a ring network. Claim 9 In claim 1, the first and second L2 switches (110) (210) are characterized by having first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) (111) (211) of 1-core WDM that are connected to the first WDM filter (122) or the second WDM filter (222) of the OTDR module (120) and provide different wavelengths of 1310 nm and 1500 nm, respectively, for a ring network as well as linear and star optical line monitoring device. Claim 10 In claim 1, the first and second L2 switches (110) (210) are characterized by having first and second SFP-GBICs (Small Form-factor Pluggable-Giga Bit Interface Converters) (111) (211) connected to the first WDM filter (122) or the second WDM filter (222) of the OTDR module (120) to provide a wavelength of 1310 nm, thereby forming a ring network as well as a linear and star optical line monitoring device. Claim 11 A linear and star optical fiber monitoring device, as well as a ring network, characterized in that, in claim 1, a dedicated EMS (Element Management System) (300) can be operated externally or internally, which is connected to the first L2 switch (110) of the central processing terminal (100) via TCP / IP or I2C communication and displays the location of the optical fiber where the problem occurred as a graph when the optical fiber problem occurs. Claim 12 delete

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