Optical cross-connect device

Abstract

Provided is a ROADM unit (100) comprising: a WXC unit (120) having a plurality of route selector switches (121, 122); and an MCS unit (130) having a plurality of Add / Drop switches (131), wherein the route selector switches (121, 122) and the Add / Drop switches (131) are each provided with an interface unit (150) that can connect to internal wiring from the outside, and a control unit (110) that controls a connection path of the interface unit (150) is provided.

Description

Optical Cross-Connect Equipment

[0001] The present invention relates to an optical cross-connect device used for multi-band transmission in which wavelength-multiplexed signal light, in which optical signals in a plurality of different wavelength bands are multiplexed, is transmitted over an optical fiber.

[0002] Conventionally, wavelength cross-connect devices are connected as relay nodes for optical signals to optical fibers of a path (optical transmission path) that bundles together multiple optical fibers in an optical network. Wavelength cross-connect devices are used, for example, in reconfigurable optical add / drop multiplexers (ROADMs) that act as path switches for optical signals transmitted using various modulation methods such as wavelength division multiplexing in optical networks. In these wavelength cross-connect devices, wavelength-multiplexed signal light transmitted from an input path is output to an output path via multiple wavelength selective switches (WSSs) (see Non-Patent Document 1).

[0003] A WSS is an optical switch that not only has the wavelength multiplexing / demultiplexing function of connecting input WDM (Wavelength Division Multiplexing) signals to different output ports for each wavelength, but also has the ability to change the combination of wavelength and output port.By using a WSS, on-site work is not required when changing the transmitting and receiving wavelengths, and path changes can be made quickly by remote operation.

[0004] A wavelength cross-connect device enables the switching of optical signal paths in a wavelength multiplexing transmission system. Generally, a wavelength cross-connect device is capable of switching any optical path.

[0005] FIG. 16 is a diagram illustrating the configuration of a wavelength multiplexing transmission system equipped with a wavelength cross-connect device. The wavelength multiplexing transmission system 1 illustrated in FIG. 16 is an optical transmission system based on Dense Wave-Division Multiplexing (DWDM), which multiplexes multiple wavelength signals onto a single optical fiber, and digital coherent technology. The wavelength multiplexing transmission system 1 includes a ROADM unit 10 constituting an optical cross-connect device (OXC), which is an optical node; optical transmission paths 50A and 50B (collectively referred to as paths 50) consisting of optical fibers connecting the OXCs; an OXC Network Operation System (NE-OpS) server 60 that controls the ROADM unit 10; and a monitoring and control terminal 70 that monitors the wavelength multiplexing transmission system 1 in cooperation with the OXC NE-OpS server 60. The OXC NE-OpS server 60 controls and operates the operation and maintenance of the ROADM unit 10. The monitoring and control terminal 70 is configured by a computer (not shown).

[0006] The ROADM unit 10 performs processes such as relaying optical signals between OXCs and switching the path of optical signals. The ROADM unit 10 is an OXC that can set any optical path to be added, dropped, or passed through on the transmission line. The ROADM unit 10 is composed of a combination of packages such as a wavelength cross connect unit (WXC unit) 20 and a multicast switch unit (MCS unit) 30, and the packages are connected by optical cables 23.

[0007] The WXC unit 20 is an optical cross-connect unit that can set any optical path to be added, dropped, or passed through a transmission line. The WXC unit 20 includes a route changeover switch 21 that switches the optical signal route on the route (route 1 to N) 50A side, a route changeover switch 22 that switches the optical signal route on the route (route 1 to M) 50B side, and an optical cable 23 that connects the route changeover switches 21 and 22 and an add / drop switch (optical multiplexing / demultiplexing unit) 31.

[0008] The route changeover switches 21 and 22 are WSSs. The optical cable 23 is a line connecting each package, and the number of lines connecting each package requires the wiring of a spectral cable. The optical cable 23 is mainly an MPO (Multi-Fiber Push On) cable or the like, in which multiple cores are connected together (see Non-Patent Document 2).

[0009] The MCS unit 30 includes an add / drop switch 31, which is a multiplexer / demultiplexer. The add / drop switch 31 multiplexes optical signals of different wavelengths and demultiplexes the multiplexed optical signals.

[0010] The ROADM unit 10 transmits an optical signal of a specified wavelength to a specified path in response to instructions from the OXC NE-OpS server 60. The ROADM unit 10 performs switching to transmit the optical signal to either the WXC unit 20, the client, or the optical transmission path. The WXC unit 20 is equipped with an Add / Drop switch 31, which enables the insertion (Add) and separation (Drop) of optical paths, enabling the addition and dropping of any optical path.

[0011] Mitsushi Fukutoku and two others, "Optical Node and Switch Technology for Flexible and Economical Networks," NTT Technical Journal, [online], [Retrieved August 1, 2024], Internet <URL: https: / / journal.ntt.co.jp / backnumber2 / 1311 / files / jn201311012.pdf> Minoru Fujiwara and three others, "Optical Fiber Communications News: MPO Connector Edition," JANOG51, January 27, 2023, [online], [Retrieved August 1, 2024], Internet <URL: https: / / www.janog.gr.jp / meeting / janog51 / wp-content / uploads / 2022 / 12 / janog51-mpo-fujiwara.pdf>

[0012] However, in the above-described wavelength multiplexing transmission system 1, the ROADM unit 10 is divided into packages such as the WXC unit 20 and the MCS unit 30, and the number of wirings between each package is increased because they are connected in a full mesh. In addition, there are issues such as an increase in the number of optical cables 23 and an increase in the operational burden, such as checking the normality and replacing the optical cables when they fail, when managing optical cables bundled together with an MPO cable.

[0013] Specific problems are as follows. (Problem 1) Figure 17 is a diagram illustrating problem 1 in the ROADM unit 10 of the wavelength multiplexing transmission system 1 of Figure 16. Components that are the same as those in Figure 16 are assigned the same reference numerals. In the wavelength multiplexing transmission system 1, it is necessary to check the normality of the connections between each package (WXC unit 20, MCS unit 30) before service starts (before the main signal is conducted). To check the normality of the connections between each package, a test light source module 40 is provided in each package. In Figure 17, the route changeover switches 21 and 22 of the WXC unit 20 and the add / drop switch 31 of the MCS unit 30 each include a test light source module 40 therein. The test light source module 40 has a light-emitting function unit and a light-receiving function unit (not shown), and the normality of the connections between each package (wiring check) is checked using the test light source module 40 (see the thick solid line aa in Figure 17). The test light source module 40 is used only to check the normality of the connections between the packages before the start of service, and is not used during actual operation. In this way, since the test light source module 40 for checking the wiring is added to each package, there are problems such as an increase in the failure rate due to the increase in parts and an increase in costs.

[0014] (Problem 2) Figure 18 is a diagram illustrating a problem (Problem 2) in the ROADM unit 10 of the wavelength multiplexing transmission system 1 of Figure 16. The same components as in Figure 16 are assigned the same reference numerals. As indicated by the reference numeral bb in Figure 18, if a failure occurs in the wiring between packages, the package or the optical cable 23 must be replaced, resulting in a long recovery time. In many cases, the optical cable 23 between packages is connected by an MPO cable. With an MPO cable, even a failure in a single core necessitates the replacement of wiring between multiple packages, significantly impacting the impact of the replacement. In other words, if the internal wiring is connected by an MPO cable, the impact of the replacement of a wiring failure is significant.

[0015] The present invention has been made in consideration of the above circumstances, and its object is to provide an optical cross-connect device that can check the normality of the connections between each package without having to provide a test light source module in each package.

[0016] In order to solve the above-mentioned problems, an optical cross-connect device is provided which comprises a wavelength cross-connect section having a plurality of path changeover switches and a multicast switch section having a plurality of add-drop switches, wherein each of the path changeover switches and each of the add-drop switches comprises an interface section which can be connected to internal wiring from the outside, and a control section which controls the connection path of the interface section.

[0017] According to the present invention, it is possible to provide an optical cross-connect device that can check the normality of the connections between packages without providing a test light source module in each package.

[0018] 1 is a configuration diagram showing a wavelength multiplexing transmission system including an optical cross connect device according to a first embodiment of the present invention. FIG. 2 is a diagram explaining an application example of normality check of internal wiring of the optical cross connect device according to the first embodiment of the present invention. FIG. 3 is a diagram explaining in more detail an application example of normality check of internal wiring of the optical cross connect device according to the first embodiment of the present invention. FIG. 4 is a configuration example in which a route changeover switch A of the optical cross connect device according to the first embodiment of the present invention is connected to port 1 and a route changeover switch B of the optical cross connect device according to the first embodiment of the present invention is connected to port 21. FIG. 5 is a setting flow of a control unit when realizing an operation example of the optical cross connect device according to the first embodiment of the present invention. FIG. 6 is a diagram explaining an application example of normality check of external wiring of the optical cross connect device according to the first embodiment of the present invention. FIG. 7 is a diagram explaining an operation example in normality check of external wiring of the optical cross connect device according to the second embodiment of the present invention. FIG. 8 is a diagram explaining N+1 redundancy of wiring of the optical cross connect device according to the third embodiment of the present invention. FIG. 9 is a diagram explaining an application example of N+1 redundancy of wiring of the optical cross connect device according to the third embodiment of the present invention. 16 is a diagram illustrating an example of operation in N+1 redundancy of wiring occupying one port of a WSS of an optical cross connect device according to a third embodiment of the present invention. FIG. 17 is a diagram illustrating a setting flow of a control unit when realizing an example of operation of the optical cross connect device according to the third embodiment of the present invention. FIG. 18 is a diagram illustrating N+1 redundancy of wiring of an optical cross connect device according to the third embodiment of the present invention. FIG. 19 is a diagram illustrating an example of application of N+1 redundancy of wiring in which an optical switch is provided in a subsequent stage of a WSS of an optical cross connect device according to a fourth embodiment of the present invention. FIG. 19 is a diagram illustrating a configuration of a wavelength multiplexing transmission system including a ROADM unit of the related art. FIG. 19 is a diagram illustrating a problem (problem 1) in the ROADM unit of the wavelength multiplexing transmission system of FIG. 16. FIG. 20 is a diagram illustrating a problem (problem 2) in the ROADM unit of the wavelength multiplexing transmission system of FIG.

[0019] Hereinafter, an optical network system and the like in an embodiment for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described with reference to the drawings. (First Embodiment) Fig. 1 is a configuration diagram showing a wavelength multiplexing transmission system equipped with an optical cross-connect device according to a first embodiment of the present invention. Components that are the same as those in Fig. 16 are assigned the same reference numerals.

[0020] 1 includes a ROADM unit 100 (optical cross-connect device) constituting an OXC, which is an optical node; paths (optical transmission paths) 50A, 50B (collectively referred to as paths 50) made of optical fibers that connect the OXCs; an OXC NE-OpS server 60 that controls the ROADM unit 100; and a monitoring and control terminal 70 that monitors the wavelength multiplexing transmission system 1000 in cooperation with the OXC NE-OpS server 60. The OXC NE-OpS server 60 controls and operates the operation and maintenance of the ROADM unit 100.

[0021] The ROADM unit 100 performs processes such as relaying optical signals between OXCs and switching the direction of optical signals. Similar to the ROADM unit 10 in Fig. 16, the ROADM unit 100 is an OXC that can set any optical path to be added, dropped, or passed through on the transmission line. The ROADM unit 100 is configured by combining packages such as a wavelength cross-connect unit (WXC unit) 120 and a multicast switch unit (MCS unit) 130, and the packages are connected by optical cables 23.

[0022] The WXC unit 120 includes a route changeover switch 121 that switches the optical signal route on the route (route 1 to N) 50A side, a route changeover switch 122 that switches the optical signal route on the route (route 1 to M) 50B side, an optical cable 23 that connects the route changeover switches 121, 122 and an Add / Drop switch 131 (add / drop switch), and a control unit 110 that has a normality confirmation tool 111 inside.

[0023] The route changeover switches 121 and 122 are WSSs, similar to the route changeover switches 21 and 22 in Fig. 16. The route changeover switches 121 and 122 include an interface unit 150, which is a port unit that can connect an optical cable 23 (external) to internal wiring.

[0024] The optical cable 23 is a line connecting each package, and the number of lines connecting each package requires wiring of a spectral cable. The optical cable 23 may be an MPO cable or the like in which multiple cores are connected together.

[0025] The MCS unit 130 includes an add / drop switch 131, which is a multiplexer / demultiplexer. The add / drop switch 131 multiplexes optical signals of different wavelengths and demultiplexes the multiplexed optical signals. Similar to the path changeover switches 21 and 22, the add / drop switch 131 includes an interface unit 150, which is a port that can be connected from an optical cable 23 (external) to internal wiring.

[0026] The control unit 110 performs control to switch the internal wiring paths of the route changeover switches 121 and 122 and the Add / Drop switch 131 to external interfaces via the interface unit 150 in accordance with instructions from the OXC NE-OpS server 60 .

[0027] The normality confirmation tool 111 has the function of measuring a test light source module and power level, and is connected to the interface section 150 of the route changeover switches 121, 122 and the add / drop switch 131 to confirm the normality of the internal wiring of the route changeover switches 121, 122 and the add / drop switch 131.

[0028] In the ROADM section 100, each package (WXC section 120, MCS section 130) does not have a test light source module 40 like the ROADM section 10 in Figure 15, but instead the route changeover switches 121, 122 and the Add / Drop switch 131 have an interface section 150 which is a port function to which an optical cable 23 can be connected, and a control section 110 which has a normality confirmation tool 111 inside.

[0029] The operation of the ROADM unit 100 of the wavelength multiplexing transmission system 1000 configured as described above will now be described.

[0030] <Application Example of Checking the Normality of Internal Wiring> The first embodiment is an example in which the normality of internal wiring is checked in the ROADM unit 100 of Fig. 1. Fig. 2 is a diagram illustrating an application example of checking the normality of internal wiring in the ROADM unit 100 of Fig. 1. The ROADM unit 100 includes route changeover switches 121 and 122 and an add / drop switch 131, an interface unit 150, and a control unit 110 having an internal normality check tool 111. The normality check tool 111 of the control unit 110 is connected to the interface unit 150 of the route changeover switches 121 and 122 or the add / drop switch 131, which are targets for checking the normality of the internal wiring. In Figure 2, a normality confirmation tool 111 is connected to the interface section 150 of the route changeover switch 121 on the route 1 side and the interface section 150 of the route changeover switch 122 on the route M side, and the normality confirmation tool 111 is connected to the internal wiring from the outside to the relevant route changeover switches 121 and 122 (see the thick solid line in Figure 2).

[0031] FIG. 3 is a diagram illustrating in more detail an example of an application of normality checking of the internal wiring of the ROADM unit 100 of FIG. 2 . The route switches 121 and 122 shown in FIG. 3 are configured with WSSs, one for transmission and one for reception (hereinafter, referred to as WSS×2). The route switches 121 and 122 have multiple ports to establish full-mesh connections with other route switches. Like the route switch 121, the route switch 122 has multiple ports, but the number of ports is omitted for simplicity. In FIG. 3 , a normality checking tool 111 is connected to the interface unit 150 of the route switch 121 and the interface unit 150 of the route switch 122 on the route M side, and the normality checking tool 111 is connected to the internal wiring of the route switches 121 and 122 from the outside (see the thick solid lines in FIG. 3 ). The normality of the internal wiring connecting the first port of the route changeover switch 121 and the route changeover switch 122 is confirmed (see the thick solid line in FIG. 3).

[0032] Here, the normality confirmation tool 111 may be provided outside the package. Hereinafter, a normality confirmation tool provided outside the package will be referred to as an "external tool." Instead of the normality confirmation tool 111, an external tool may be connected to the interface unit 150, and cooperation with an external normality confirmation tool (external tool) is also possible.

[0033] <Example of operation of the control unit for checking the normality of internal wiring> An example of operation of the control unit for checking the normality of internal wiring will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a diagram showing an example of operation in checking the normality of internal wiring in Fig. 3, and Fig. 5 is a setting flow of the control unit 110 when realizing the example of operation in Fig. 4.

[0034] Prerequisite: The route changeover switch 121 (route changeover switch A) and the route changeover switch 122 (route changeover switch B) are mounted on the ROADM section 100 (ROADM device) (Figure 1) and are internally wired using an MPO cable or the like.

[0035] FIG. 4 shows an example of a configuration in which the route changeover switch 121 (route changeover switch A) is connected to port 1, and the route changeover switch 122 (route changeover switch B) is connected to port 21 (see the thick solid line a in FIG. 4).

[0036] In step S11 of Fig. 5, a setting is added from the control function program of the OXC NE-OpS server 60 (Fig. 1) to connect "Port 1 of Route Switch A" to "Port 21 of Route Switch B" (thick solid line a in Fig. 4). Note that due to space limitations, A and B in the flow of Fig. 5 represent route switches A and B (the same notation is used for route switches hereinafter).

[0037] Assume that there is a request to check the normality of the wiring between port A-1 and port B-21 in step S12. Specifically, upon receiving the request to check the normality of the internal wiring from OXC NE-OpS server 60, control unit 110 (FIG. 1) issues a setting change (S1) to route change switch 121 (route change switch A) and also issues a setting change (S2) to route change switch 122 (route change switch B).

[0038] The above steps S11 and S12 are implemented by existing functions, and the settings for which ports of the route changeover switch are connected can be changed. The flow of steps S13 to S16 described below is a new function.

[0039] In step S13, the control unit 110 physically connects the normality confirmation tool 111 to the external interfaces A and B (solid line b in FIG. 4). In FIG. 4, the interface unit 150 provided in the route changeover switch 121 (route changeover switch A) is the external interface A, and the interface unit 150 provided in the route changeover switch 122 (route changeover switch B) is the external interface B.

[0040] In step S14, the control unit 110 changes the settings as follows (thick dashed line c in FIG. 4): The normality confirmation tool 111 and external interfaces A and B are physically connected, and as shown by the thick arrow d in FIG. 4, the test light emitted from the normality confirmation tool 111 is input to the WSS of the route changeover switch A via external interface A.

[0041] Light input from external interface A is output to "Port 1 of route changeover switch A" on the WSS. Light input from "Port 21 of route changeover switch B" on the WSS is output to external interface B.

[0042] As indicated by the thick arrow e in FIG. 4, the measurement light output from the external interface B is input to the normality confirmation tool 111.

[0043] In step S15, the control unit 110 causes the normality confirmation tool 111 to emit test light (thick arrow d in FIG. 4).

[0044] In step S16, the control unit 110 receives the test light emitted from the normality confirmation tool 111 (thick arrow e in Figure 4), outputs the test results (communication result, optical power level) to the OXC NE-OpS server 60, and ends this flow.

[0045] As described above, in the ROADM section 100 (optical cross-connect device) of this embodiment, the route changeover switches 121, 122 and the Add / Drop switch 131 have an interface section 150 that can be connected to the internal wiring from the outside, and a test light source module and a normality confirmation tool 111 that has the function of measuring power levels are connected to the interface section 150, and the normality of the internal wiring is confirmed using the normality confirmation tool 111.

[0046] In this way, the ROADM unit 100 uses the interface unit 150 and the normality confirmation tool 111 in the control unit 110, thereby enabling normality confirmation of the internal wiring, as shown in FIG. 4, for example. Normality confirmation of the connections between packages can be performed without providing a test light source module (test light source module 40 in FIG. 17) in each package (route switches 121 and 122, add / drop switch 131). Furthermore, by aggregating light source modules for checking the normality of the wiring, the ROADM unit 100 has the effect of reducing the failure rate of each package and reducing costs.

[0047] Second Embodiment The second embodiment is an example in which the normality of external wiring is confirmed in the ROADM unit 100 of Fig. 1. Fig. 6 is a diagram illustrating an application example of normality confirmation of external wiring of the ROADM unit 100 of Fig. 1. The route changeover switches 121 and 122 shown in Fig. 6 have main signal ports 121a and 122a. In Fig. 6, the normality confirmation tool 111 is connected to the interface unit 150 of the route changeover switch 121, and the interface unit 150 is connected to port 1 of the route changeover switch 121 and the route changeover switch 122, and the output of the route changeover switch 122 is further connected to the main signal port 122a, thereby making it possible to confirm the normality of the internal wiring in the same manner as in the first embodiment (see the thick solid line f in Fig. 6).

[0048] In particular, the second embodiment can also be used to measure the power level of the main signal by connecting the normality confirmation tool 111 to the interface unit 150 of the route switching switch 121 and inputting an optical signal input to the main signal port 121a of the route switching switch 121 from port 31 of the route switching switch 121 to the normality confirmation tool 111 via the interface unit 150 (see thick dashed line g in Figure 6).

[0049] <Example of operation of the control unit for checking the normality of external wiring> An example of operation of the control unit for checking the normality of external wiring will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a diagram showing an example of operation in checking the normality of external wiring in Fig. 8, and Fig. 8 is a setting flow of the control unit 110 when realizing the example of operation in Fig. 7.

[0050] Prerequisite: It is assumed that the route changeover switch 121 (route changeover switch A) and the route changeover switch 122 (route changeover switch B) are mounted on the ROADM unit 100 (ROADM device) (FIG. 1) and externally wired.

[0051] FIG. 7 shows an example of a configuration for checking the normality of external wiring connected to the route changeover switch 121 (route changeover switch A) and the route changeover switch 122 (route changeover switch B).

[0052] In step S21 of FIG. 8, the control function program of the OXC NE-OpS server 60 (FIG. 1) enables the main signal port of the route changeover switch A and the main signal port of the route changeover switch B, so that the route changeover switch A and the route changeover switch B can receive the main signal (thick solid line h in FIG. 7).

[0053] In step S22, it is assumed that a main signal confirmation request is made to route changeover switch A and route changeover switch B. Specifically, upon receiving a request to confirm the normality of the internal wiring from OXC NE-OpS server 60, control unit 110 (FIG. 1) issues a setting change (S1) to route changeover switch 121 (route changeover switch A) and also issues a setting change (S2) to route changeover switch 122 (route changeover switch B).

[0054] The above steps S21 and S22 are implemented by existing functions, and the settings for which ports of the route changeover switch are connected can be changed. The flow from steps S23 to S25 described below is a new function.

[0055] In step S23, the control unit 110 physically connects the normality confirmation tool 111 to the external interfaces A and B (solid line i in FIG. 7). In FIG. 7, the interface unit 150 provided in the route changeover switch 121 (route changeover switch A) is the external interface A, and the interface unit 150 provided in the route changeover switch 122 (route changeover switch B) is the external interface B.

[0056] Here, the settings change depending on the implementation example of the path the received light takes, so two patterns, <Implementation Example 1> and <Implementation Example 2>, are described.

[0057] <Implementation example 1> is a setting flow that proceeds from step S23 to step S25 via a setting change in step S24A, and <Implementation example 2> is a setting flow that proceeds from step S23 to step S25 via a setting change in step S24B. Also, <Implementation example 1> is an example of checking the normality of the external wiring in the route changeover switch 121 (route changeover switch A) in Fig. 7, and <Implementation example 2> is an example of checking the normality of the external wiring in the route changeover switch 122 (route changeover switch B) in Fig. 7.

[0058] In step S24A, the control unit 110 performs the following setting change in <Implementation Example 1>. The light input from the main signal port 121a of the route changeover switch A (thick solid line h in FIG. 7) is output from the WSS to the external interface A (thick dashed line j in FIG. 7). As indicated by the arrow i in the left diagram in FIG. 7, the measurement light output from the external interface A is input to the normality confirmation tool 111.

[0059] On the other hand, in <Implementation Example 2> of step S24B, the control unit 110 makes the following setting changes: Light input from the main signal port of the route switching switch B (thick solid line h in FIG. 7) passes through port 32 (a specific port connected to an external interface) of the route switching switch B and is output to the external interface B (thick dashed line k in FIG. 7). As indicated by arrow i in the right diagram of FIG. 7, the measurement light output from the external interface B is input to the normality confirmation tool 111.

[0060] In step S25, the control unit 110 receives the test light emitted from the normality confirmation tool 111 (thick arrow h in Figure 7), outputs the test results (communication result, optical power level) to the OXC NE-OpS server 60 (Figure 1), and ends this flow.

[0061] As described above, in the ROADM section 100 (optical cross-connect device) of this embodiment, the route changeover switches 121, 122 and the Add / Drop switch 131 have an interface section 150 that can be connected to the internal wiring from the outside, and a test light source module and a normality confirmation tool 111 that has the function of measuring power levels are connected to the interface section 150, and the normality of the external wiring is confirmed using the normality confirmation tool 111.

[0062] In this way, the ROADM unit 100 uses the interface unit 150 and the normality confirmation tool 111 in the control unit 110, thereby making it possible to confirm the normality of the external wiring, as shown in Fig. 6, for example. The ROADM unit 100 can also be used to confirm the normality of the external wiring.

[0063] (Third Embodiment) In the third embodiment, a detour path is constructed as an alternative line for a failed wiring (N+1 redundancy of wiring) by using the interface unit 150. The third embodiment is a configuration example in which one port of the WSS is occupied.

[0064] 9 is a diagram illustrating N+1 redundancy of the wiring of the ROADM unit 100 in FIG. 1. As shown in FIG. 9, assume that a failure occurs in the wiring between the route changeover switch 121 on the input route 1 side and the route changeover switch 122 on the output route 1 side (symbol l in FIG. 9). In this embodiment, the ROADM unit 100 can construct a detour path as an alternative line for the failed wiring by using the interface unit 150 provided in each route changeover switch 121, 122 (thick solid line in FIG. 9).

[0065] <Example of Application of N+1 Redundancy to Wiring Occupying One Port of WSS> Figure 10 is a diagram illustrating an example of application of N+1 redundancy to the wiring of Figure 9. As shown in Figure 10, one port of the WSS is reserved for redundancy. Specifically, port 32 of route changeover switch 121 is occupied as a detour (bold solid line m in Figure 10), and a port of route changeover switch 122 is occupied as a detour (bold solid line o in Figure 10), and the interface unit 150 of route changeover switch 121 is connected to the interface unit 150 of route changeover switch 122 (bold solid line n in Figure 10).

[0066] In this way, one port of the WSS is reserved for redundancy, and in the event of a failure in another port, a detour route is realized by routing the detour route via the monitor port (N+1 redundancy).

[0067] <Example of operation of the control unit for N+1 redundancy of wiring occupying one port of a WSS> An example of operation of the control unit for N+1 redundancy of wiring occupying one port of a WSS will be described with reference to Figures 11 and 12. Figure 11 is a diagram showing an example of operation in N+1 redundancy of wiring occupying one port of the WSS in Figure 10, and Figure 12 is a setting flow of the control unit 110 when realizing the example of operation in Figure 11.

[0068] Prerequisite: The route changeover switch 121 (route changeover switch A) and the route changeover switch 122 (route changeover switch B) are mounted on the ROADM section 100 (ROADM device) (Figure 1) and are internally wired using an MPO cable or the like.

[0069] FIG. 11 shows an example of a configuration in which the route changeover switch 121 (route changeover switch A) is connected to port 1, and the route changeover switch 122 (route changeover switch B) is connected to port 21.

[0070] 12, a fault occurs in the internal wiring between port 1 of route changeover switch A and port 21 of route changeover switch B (symbol l, thick dashed line p in FIG. 11). This fault can be detected by checking the normality of the internal wiring in the first embodiment.

[0071] In step S32, a setting is added from the control function program of the OXC NE-OpS server 60 (FIG. 1) to connect "Port 1 of Route Switch A" to "Port 21 of Route Switch B" (thick solid lines m and o in FIG. 11).

[0072] In step S33, the control unit 110 physically connects the external interfaces A and B (thick solid line n in FIG. 11).

[0073] In step S34, the control unit 110 makes the following setting changes: If the external interface is connected to port 32, the setting is changed to connect "port 32 of route changeover switch A" to "port 32 of route changeover switch B" (thick solid lines m and o in FIG. 11).

[0074] In step S35, the control unit 110 completes the setting and restoration of a detour route in the event of an internal wiring failure, and ends this flow.

[0075] As described above, the ROADM section 100 (optical cross-connect device) of this embodiment can construct a detour route as an alternative line to a faulty wiring by using the interface section 150 provided in each route changeover switch 121, 122.

[0076] The ROADM unit 100 can shorten the time required to restore services by serving as a restoration means in the event of a wiring failure. In particular, it can restore services when one wiring in an MPO cable that bundles multiple wiring fails, preventing the impact on other packages when the MPO is replaced.

[0077] (Fourth embodiment) In the fourth embodiment, a detour path is constructed as an alternative line for a failed wiring (N+1 redundancy of wiring) by using the interface unit 150. The fourth embodiment is a configuration example in which an optical switch 124 is provided after the WSS.

[0078] Fig. 13 is a diagram illustrating N+1 redundancy of the wiring of the ROADM unit 100 in Fig. 1. As shown in Fig. 13, the route changeover switches 121 and 122 include an optical switch 124 after the WSS. As shown in Fig. 13, it is assumed that a failure occurs in the wiring between the route changeover switch 121 on the input route 1 side and the route changeover switch 122 on the output route 1 side (symbol l in Fig. 13).

[0079] In this embodiment, the ROADM unit 100 can construct a detour route as an alternative line to the failed wiring by using the interface unit 150 provided in each route changeover switch 121, 122 (thick solid line in Figure 9).

[0080] <Example of application of N+1 redundancy in wiring with optical switch 124 provided at the rear of WSS> Fig. 14 is a diagram illustrating an example of application of N+1 redundancy in wiring with optical switch 124 provided at the rear of WSS in Fig. 13. As shown in Fig. 14, an optical switch 124 is provided at the rear of WSS. Specifically, a route changeover switch 121 (route changeover switch A) is connected to port 1, and a route changeover switch 121 (route changeover switch B) is connected to port 21.

[0081] <Example of operation of the control unit for N+1 redundancy of wiring in which an optical switch 124 is provided after the WSS> An example of operation of the control unit for N+1 redundancy of wiring in which an optical switch 124 is provided after the WSS will be described with reference to Figures 14 and 15. Figure 14 is a diagram showing an example of operation in N+1 redundancy of wiring in which an optical switch 124 is provided after the WSS in Figure 13, and Figure 15 is a setting flow of the control unit 110 when realizing the example of operation in Figure 14.

[0082] Prerequisite: The route changeover switch 121 (route changeover switch A) and the route changeover switch 122 (route changeover switch B) are mounted on the ROADM section 100 (ROADM device) (Figure 1) and are internally wired using an MPO cable or the like.

[0083] 15, a fault occurs in the internal wiring between port 1 of route changeover switch A and port 21 of route changeover switch B (symbol l, thick dashed line p in FIG. 14). This fault can be detected by checking the normality of the internal wiring in the first embodiment.

[0084] In step S42, a setting is added from the control function program of the OXC NE-OpS server 60 (FIG. 1) to connect "Port 1 of Route Switch A" to "Port 21 of Route Switch B" (thick solid lines m and o in FIG. 14).

[0085] In step S43, the control unit 110 physically connects the external interfaces A and B (thick solid line n in FIG. 14).

[0086] In step S44, the control unit 110 makes the following setting changes: "Port 1 of route switch A" of the optical switch 124 of route switch A is switched to a path for the external interface. "Port 21 of route switch B" of the optical switch 124 of route switch B is changed to a setting to switch and connect to a path for the external interface (thick solid lines m and o in FIG. 14).

[0087] In step S45, the control unit 110 completes the setting and restoration of a detour route in the event of an internal wiring failure, and then ends this flow.

[0088] As described above, the ROADM unit 100 (optical cross-connect device) of this embodiment can construct a detour path as an alternative line to a failed wiring by using the interface unit 150 provided in each of the route changeover switches 121 and 122. As in the third embodiment, the ROADM unit 100 can shorten the time required to restore service by serving as a restoration means in the event of a wiring failure. This enables restoration when one wiring in an MPO cable that bundles multiple wirings fails, and can prevent the impact on other packages when the MPO is replaced.

[0089] Furthermore, in this embodiment, the ROADM unit 100 has the optical switch 124 disposed after the WSS, which has the advantage of not occupying the WSS port (not blocking the port).

[0090] [Effects] As described above, the optical cross-connect device (ROADM section 100) (FIG. 1) includes a wavelength cross-connect section (WXC section 120) having a plurality of path changeover switches 121, 122, and a multicast switch section (MCS section 130) having a plurality of add / drop switches (add / drop switches 131), and each of the path changeover switches 121, 122 and each add / drop switch (add / drop switch 131) includes an interface section 150 (FIG. 1) connectable to internal wiring from the outside, and includes a control section 110 (FIG. 1) that controls the connection path of the interface section 150.

[0091] Also, there is provided a method for confirming the normality of an optical cross-connect in an optical cross-connect device (ROADM section 100) that includes a wavelength cross-connect section (WXC section 120) having a plurality of path changeover switches 121, 122, and a multicast switch section (MCS section 130) having a plurality of add / drop switches (add / drop switches 131), in which each of the path changeover switches 121, 122 and each add / drop switch (add / drop switch 131) has an interface section 150 that can be connected to the internal wiring from the outside, and a test light source module and a normality confirmation tool 111 having a function of measuring power levels are connected to the interface section 150, and the normality of the internal wiring or the normality of the external wiring is confirmed using the normality confirmation tool 111.

[0092] By doing so, the optical cross-connect device (ROADM unit 100) can check the normality of the connections between each package without providing a test light source module in each package. Also, by consolidating the light source modules for checking the normality of the wiring, the failure rate of each package can be reduced, leading to cost savings.

[0093] The optical cross-connect device (ROADM unit 100) (FIG. 1) further includes a light source module for testing and a normality checking tool 111 having a function for measuring the power level.

[0094] By doing so, the optical cross-connect device (ROADM unit 100) can aggregate light source modules for checking the normality of the wiring, leading to a reduction in the failure rate of each package and a reduction in costs.

[0095] In the optical cross-connect device (ROADM section 100) (Figure 1), the control section 110 (Figure 1) connects a normality confirmation tool 111 to the interface section 150 and uses the normality confirmation tool 111 to confirm the normality of the internal wiring or the normality of the external wiring.

[0096] The interface unit 150 has a degree of freedom in connection, allowing the normality confirmation tool 111 and other external tools to be connected arbitrarily. Therefore, the normality of the internal wiring or the normality of the external wiring can be confirmed using the normality confirmation tool connected to the interface unit 150.

[0097] In the optical cross-connect device (ROADM section 100) (Figure 1), when the internal wiring or external wiring fails, the control section 110 controls the connection path of the interface section 150 to enable connection of an alternative line to the failed wiring via the interface section 150.

[0098] By doing so, the interface unit 150 can be used to create a detour path as an alternative line to a failed wiring. In particular, by using it as a restoration means in the event of a wiring failure, the time required to restore service can be shortened. Also, restoration is possible when one wiring in an MPO cable that bundles multiple wiring fails, and it is possible to prevent the impact on other packages when replacing it.

[0099] Furthermore, among the processes described in the above embodiments, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically using known methods. In addition, the processing procedures, control procedures, specific names, and information including various data and parameters shown in the above documents and drawings can be changed as desired unless otherwise specified. Furthermore, the components of each device shown in the drawings are functionally conceptual and do not necessarily have to be physically configured as shown. In other words, the specific form of distribution and integration of each device is not limited to that shown in the drawings, and all or part of the devices can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc.

[0100] Furthermore, the above-described configurations, functions, processing units, processing means, etc. may be partially or entirely implemented in hardware, for example, by designing them as integrated circuits. The above-described configurations, functions, etc. may also be implemented by software that causes a processor to interpret and execute programs that implement the respective functions. Information such as programs, tables, and files that implement the respective functions may be stored in a memory, a recording device such as a hard disk or a solid-state drive (SSD), or a recording medium such as an integrated circuit (IC) card, a secure digital (SD) card, or an optical disk.

[0101] 23 Optical cable 50, 50A, 50B Direction (optical transmission path) 60 OXC NE-OpS server 70 Monitoring and control terminal 100 ROADM section (optical cross-connect device) 110 Control section 111 Normality confirmation tool 120 Wavelength cross-connect section (WXC section) 130 Multicast switch section (MCS section) 121, 122 Direction changeover switch 124 Optical switch 131 Add / Drop switch (add / drop switch) 1000 Wavelength multiplexing transmission system

Claims

1. An optical cross-connect device comprising a wavelength cross-connect section having a plurality of path changeover switches and a multicast switch section having a plurality of add / drop switches, wherein each of the path changeover switches and each of the add / drop switches has an interface section that can be connected to internal wiring from the outside, and a control section that controls the connection path of the interface section.

2. The optical cross-connect device according to claim 1, further comprising a test light source module and a normality checking tool having a function of measuring power levels.

3. The optical cross-connect device described in claim 2, characterized in that the control unit connects the normality confirmation tool to the interface unit and uses the normality confirmation tool to confirm the normality of the internal wiring or the normality of the external wiring.

4. The optical cross-connect device of claim 1, characterized in that, when the internal wiring or external wiring fails, the control unit controls the connection path of the interface unit to enable connection of an alternative line to the failed wiring via the interface unit.

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