Communication device, network configuration system, communication method, and communication program

Abstract

To provide a communication device, a network configuration system, a communication method, and a communication program that can improve transmission performance.SOLUTION: A communication device includes a node included in a network configuration of an optical network, where the node includes layers with two or more types of different switching granularities, and the node is inter-layer connected to a node of an adjacent other communication device. The node includes a wavelength cross-connect layer containing a wavelength cross-connect switch that performs switching in wavelength units, and a fiber cross-connect layer containing a fiber cross-connect switch that performs switching in fiber units. The wavelength cross-connect switch and the fiber cross-connect switch may each be connected to the node of the adjacent other communication device.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a communication device, a network configuration system, a communication method, and a communication program. [Background technology]

[0002] Patent Document 1 describes an optical cross-connect network. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-262319 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-198485 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-085010 [Patent Document 4] Japanese Patent Application Laid-Open No. 2004-072238 [Patent Document 5] Japanese Patent Application Laid-Open No. 2001-045052 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to improve transmission performance in networks.

[0005] One of the purposes of the present disclosure has been made to solve the above problem, and is to provide a communication device, a network configuration system, a communication method, and a communication program that can improve transmission performance. [Means for solving the problem]

[0006] The communication device according to the present disclosure comprises a node included in a network configuration in an optical network, the node including two or more layers of heterogeneous switch granularity, and the layers are connected to nodes of other adjacent communication devices.

[0007] The network configuration system of the present disclosure comprises a plurality of communication devices including nodes included in a network configuration in an optical network, the nodes of each communication device including layers of two or more types of heterogeneous switch granularity, and the nodes of a first communication device are connected between the layers and the nodes of an adjacent second communication device.

[0008] The communication method according to the present disclosure includes a step of connecting layers between a node included in a network configuration in an optical network, the node including layers of two or more types of heterogeneous switch granularity, and another adjacent node.

[0009] The communication program of the present disclosure causes a computer to execute a step of connecting layers between a node included in a network configuration in an optical network, the node including layers of two or more types of heterogeneous switch granularity, and another adjacent node. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a communication device, a network configuration system, a communication method, and a communication program that can improve transmission performance. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating the concept of a wavelength cross-connect system and a network configuration according to the present disclosure; [Figure 2] FIG. 1 is a diagram illustrating the concept of a hierarchical cross-connect system according to the present disclosure. [Figure 3] 1 is a schematic diagram illustrating wavelength group paths and wavelength path routing in a hierarchical cross-connect system according to the present disclosure; [Figure 4] FIG. 1 is a diagram illustrating a network configuration in a hierarchical cross-connect system according to the present disclosure. [Figure 5] FIG. 1 is a block diagram illustrating a communication device according to the present disclosure. [Figure 6] FIG. 1 is a flow chart illustrating a communication method according to the present disclosure. [Figure 7] FIG. 1 is a block diagram illustrating a communication device according to the present disclosure. [Figure 8] FIG. 1 illustrates a related hierarchical cross-connect network concept according to the present disclosure. [Figure 9] FIG. 1 is a diagram illustrating a network concept of a hierarchical heterogeneous routing optical network system according to the present disclosure. [Figure 10] FIG. 1 is a diagram illustrating a network configuration according to the present disclosure. [Figure 11] FIG. 1 is a diagram illustrating the operation of an optical path in a network configuration according to the present disclosure. [Figure 12] FIG. 1 is a diagram illustrating the operation of an optical path in a network configuration according to the present disclosure. [Figure 13] FIG. 10 is a flowchart illustrating the operation of an optical path in a network configuration according to the present disclosure. [Figure 14] 10 is a graph illustrating the port utilization rate when a certain number of optical paths are generated according to the present disclosure, where the horizontal axis indicates the topology model and the vertical axis indicates the port utilization rate. [Figure 15] 10 is a graph illustrating the number of WXC stages passed through in COST266 according to the present disclosure, where the horizontal axis indicates the number of stages passed through and the vertical axis indicates the number of optical paths normalized with the total number of optical paths set to 1. [Figure 16] FIG. 1 is a diagram illustrating a network concept of a hierarchical heterogeneous routing optical network system according to the present disclosure. [Figure 17] FIG. 1 is a diagram illustrating a network configuration according to the present disclosure. [Figure 18] FIG. 1 is a diagram illustrating the operation of an optical path in a network configuration according to the present disclosure. [Figure 19]FIG. 10 is a flowchart illustrating the operation of an optical path in a network configuration according to the present disclosure. [Figure 20] FIG. 1 is a diagram illustrating a network configuration according to the present disclosure. [Figure 21] FIG. 1 is a diagram illustrating the operation of an optical path in a network configuration according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] First, the problems newly discovered by the inventors will be explained. This will clarify the embodiments. Note that the problems newly discovered by the inventors are also within the scope of the technical ideas of the embodiments.

[0013] <New problem discovered by the inventor> In recent years, the rapid spread of mobile devices such as smartphones and the increasing sophistication of devices have led to large-volume data communications, such as high-definition images, resulting in a continued rapid increase in network traffic. According to a survey by the Ministry of Internal Affairs and Communications, the total download traffic of domestic broadband subscribers in fiscal year 2022 will be approximately 29.2 Tbps, continuing to grow at an annual rate of approximately 23.7%. Traffic is expected to continue to grow in the future.

[0014] In response to this, in the core networks that support high-capacity communications, development has been progressing on technologies to meet the need for higher capacity, such as wavelength division multiplexing (hereinafter referred to as WDM), which multiplexes and transmits optical signals of multiple different wavelengths on a single optical fiber, and advanced modulation methods such as dual polarization differential quadrature phase shift keying (DP-QPSK) and 16-quadrature amplitude modulation (16-QAM). Furthermore, with the advancement of 5G services in wireless communications, there is a growing need not only for higher capacity but also for low network latency.

[0015] In response to these needs, the Innovative Optical and Wireless Network (IOWN) initiative led by NTT has recently proposed the All Photonics Network (hereinafter referred to as APN), which will realize a high-capacity, low-latency network. Unlike networks that require electrical conversion at switching nodes, the APN transmits data as optical signals throughout all paths. This not only enables high-capacity communications without being constrained by the capacity of electrical switches (hereinafter referred to as electrical SW), but also enables low latency due to the elimination of the delays associated with electrical conversion.

[0016] Such APNs have challenges not found in electrical switch-based networks. In electrical switch-based networks, multiple users can share a single optical path, such as a 100 Gbps optical path, or a 10 Gbps or 1 Gbps optical path. However, in an APN, each optical path is dedicated to a single user. In other words, accommodating a large number of users requires a large number of wavelength resources, which results in a larger optical switch that controls the routes.

[0017] FIG. 1 is a diagram illustrating the concept and network configuration of a wavelength cross-connect (WXC) system according to the present disclosure. As shown in FIG. 1, each wavelength λ1 to λ12 is accommodated individually in an optical fiber 10 as a wavelength path 11. A WXC is located at each node. The WXC performs add and drop on a wavelength-by-wavelength basis, as well as route switching. In this system, an increase in wavelength resources directly leads to an increase in the size of the WXC, which leads to an increase in optical loss and cost. In response to this, a hierarchical cross-connect system has been proposed.

[0018] FIG. 2 is a diagram illustrating the concept of a hierarchical cross-connect system according to the present disclosure. FIG. 3 is a schematic diagram illustrating wavelength group paths and wavelength path routing in the hierarchical cross-connect system according to the present disclosure. As shown in FIG. 2, the hierarchical cross-connect system groups wavelengths λ1 to λ12 into multiple wavelength bands WB1 to WB3. For example, in FIG. 2, wavelengths λ1 to λ4 are grouped into wavelength band WB1, wavelengths λ5 to λ8 into wavelength band WB2, and wavelengths λ9 to λ12 into wavelength band WB3. The hierarchical cross-connect system performs switching in units of wavelength band WB. However, wavelength transfer between wavelength bands WB, as well as add and drop, requires switching in units of wavelength. For this reason, a small-scale WXC is provided at each node to enable switching in units of wavelength (grooming function). In this way, the hierarchical cross-connect method is a configuration that introduces multiple hierarchical paths (wavelength group paths and wavelength paths), and switches on a wavelength band basis, making it possible to reduce the number of switching elements. As shown in Figure 3, a wavelength path (dashed line) passes through multiple wavelength group paths (solid lines).

[0019] FIG. 4 is a diagram illustrating a network configuration in a hierarchical cross-connect system according to the present disclosure. As shown in FIG. 4, in the hierarchical cross-connect system, each node has a tandem configuration of a WXC and a waveband cross-connect (WaveBand XC, hereinafter referred to as WBXC). Adjacent nodes are connected between WBXCs. The operation of each optical path is as follows: an optical path to be added is connected from the WXC of the node to the WBXC and forwarded to the adjacent node via the WBXC. An optical path to be dropped is dropped from the WBXC via the WXC at the node. An optical path that is passed through at the node passes only through the WBXC.

[0020] Furthermore, with the hierarchical cross-connect method, if there is no wavelength switching between wavelength bands, the path passes only through the WBXC. If there is switching between wavelength bands, this can be achieved by performing grooming processing at the WXC. A two-hop optical path passes through four cross-connects. In contrast, a wavelength cross-connect network passes through three cross-connects. Although this type of hierarchical cross-connect method requires an additional WBXC, it allows for a reduction in the switch scale of the WXC and the total WBXC compared to the wavelength cross-connect method.

[0021] As prior art documents on hierarchical cross-connects, hierarchical cross-connect methods for WXC and WBXC are disclosed in Patent Documents 1, 2, and 3. Also, a hierarchical cross-connect method for WXC and fiber cross-connect (Fiber XC, hereinafter referred to as FXC) is disclosed in Patent Document 4. As a method for layering heterogeneous switches, Patent Document 5 discloses a layering method for routers (electrical SW) and optical switches. Unlike the two prior art documents mentioned above, Patent Document 5 combines optical switches and electrical SW, but one of its objectives is to reduce the number of ports on expensive routers.

[0022] By switching from a wavelength cross-connect system to a hierarchical cross-connect system, it is possible to reduce the total switch scale of the WXC and WBXC. However, in both systems, signals pass through the WXC and WBXC where bandwidth narrowing occurs, which results in a deterioration of transmission characteristics.

[0023] One of the objectives of this disclosure is to reduce the total switch size of WXC and WBXC compared to wavelength routing methods and hierarchical cross-connect methods, even if the number of wavelengths in the APN increases, and to mitigate deterioration in transmission characteristics by reducing the number of passing stages in WXC and WBXC.

[0024] The first problem with the related technologies of Patent Documents 1 to 5 and the like is that the switch scale increases due to an increase in wavelength resources in the APN. The reason for this is that in wavelength cross-connect, the WXC scale increases. Even in a hierarchical cross-connect system where a reduction in WXC scale is expected, the reduction in the total switch scale of the WXC and WBXC is limited.

[0025] The second problem with the related techniques of Patent Documents 1 to 5 and the like is that transmission performance deteriorates due to an increase in wavelength resources in the APN, because the signal passes through many WXCs and WBXCs where bandwidth narrowing occurs.

[0026] One of the objectives of the present disclosure has been made to solve the above-mentioned problems, and relates to a network configuration method and a control method in an APN, and in particular, one of the objectives is to reduce the scale of a wavelength cross-connect switch and improve transmission performance by reducing the number of passing stages of the wavelength cross-connect switch.

[0027] The nodes constituting the network of the present disclosure are composed of two layers: a WXC layer that performs switching on a wavelength-by-wavelength basis and an FXC layer that performs switching on a fiber-by-fiber basis. Switches in each layer are connected to switches in the two layers between adjacent nodes. In other words, the WXC of a node is connected to the WXC and FXC of an adjacent node. The FXC of a node is connected to the WXC and FXC of an adjacent node.

[0028] Alternatively, each node may be configured with three layers: a WXC layer that performs switching on a wavelength-by-wavelength basis, a WBXC layer that performs switching on a wavelength-by-waveband basis, and an FXC layer that performs switching on a fiber-by-fiber basis. In other words, the switches in each layer are connected to switches in any layer between adjacent nodes.

[0029] Alternatively, each node may have a wavelength converter in front of the WXC. That is, each node may be equipped with a first wavelength filter, a second wavelength filter, and a wavelength converter. The first wavelength filter separates the input from the WXC of the previous node into wavelengths that require wavelength conversion and through wavelengths. The second wavelength filter separates the input from the FXC of the previous node into wavelengths that require wavelength conversion and through wavelengths. The wavelength converter converts the wavelengths that require wavelength conversion separated by the first wavelength filter and the second wavelength filter. Each node is equipped with a wavelength converter and connects each through wavelength to the WXC.

[0030] A first effect of the present disclosure is that it is possible to suppress the switch scale in an APN even if wavelength resources increase.

[0031] A second effect of the present disclosure is that, in an APN, even if wavelength resources increase, it is possible to prevent degradation of transmission performance.

[0032] <Outline of the embodiment> Next, an overview of an embodiment will be described. FIG. 5 is a block diagram illustrating a communication device 100 according to the present disclosure. As shown in FIG. 5, the communication device 100 includes a node 101. In the following description, the communication device 100 may be described as the node 101. The node 101 is included in a network configuration in an optical network. The node 101 includes two or more layers with heterogeneous switch granularity. The multiple layers include, for example, a wavelength cross-connect layer and a fiber cross-connect layer. Note that the multiple layers may further include a wavelength band cross-connect layer. The node 101 is connected between the nodes 101 of other adjacent communication devices 100 via layers.

[0033] Next, a communication method according to the present disclosure will be described. Fig. 6 is a flowchart illustrating the communication method according to the present disclosure. As shown in Fig. 6, the communication method includes step S10 of connecting layers between a node 101 included in a network configuration in an optical network, the node 101 including layers with two or more types of heterogeneous switch granularity, and another adjacent node 101.

[0034] The communication device 100 described above may include, for example, an information processing device such as a microcomputer, a server, or a personal computer. FIG. 7 is a block diagram illustrating the communication device 100 according to the present disclosure. As shown in FIG. 7, the node 101 of the communication device 100 may further include a processor PRC, a memory MMR, a storage device STR, and a user interface UI. The storage device STR stores programs that represent processes to be executed by each component of the communication device 100. The processor PRC loads the programs from the storage device STR into the memory MMR and executes the programs. In this way, the processor PRC realizes the functions of each component of the communication device 100. The user interface UI may include input devices such as a keyboard, a mouse, and an imaging device, as well as output devices such as a display, a printer, and a speaker.

[0035] Each component of the communication device 100 may be realized by dedicated hardware. Furthermore, some or all of the components may be realized by general-purpose or dedicated circuits, processor PRCs, etc., or a combination of these. These may be configured by a single chip, or by multiple chips connected via a bus. Some or all of the components may be realized by a combination of the above-mentioned circuits, etc., and programs. Furthermore, the processor PRC may be a central processing unit (CPU), a graphics processing unit (GPU), a field-programmable gate array (FPGA), a quantum processor (quantum computer control chip), etc.

[0036] Furthermore, when some or all of the components of the communication device 100 are realized by a plurality of communication devices 100, circuits, etc., the plurality of communication devices 100, circuits, etc. may be centrally or decentralized. For example, the communication devices 100, circuits, etc. may be realized in a form in which they are connected to each other via a communication network by a client-server system, a cloud computing system, etc. Furthermore, the functions of the communication device 100 may be provided in a SaaS (Software as a Service) format.

[0037] According to this embodiment, the node 101 of the communication device 100 includes layers of two or more types of heterogeneous switch granularity. The communication device 100 is connected between layers of the node 101 of another adjacent communication device 100. This allows the communication device 100 to suppress the switch scale even if wavelength resources increase. Furthermore, the communication device 100 can suppress the deterioration of transmission performance even if wavelength resources increase. Therefore, the communication device 100 can improve transmission performance.

[0038] <Embodiment 1> Next, a detailed description will be given of the first embodiment. Below, the network configuration method of the first embodiment will be explained by dividing it into an explanation of the configuration and an explanation of the operation.

[0039] <Configuration explanation> FIG. 8 is a diagram illustrating a network concept of a related hierarchical cross-connect scheme according to the present disclosure. FIG. 9 is a diagram illustrating a network concept of a hierarchical heterogeneous routing optical network scheme according to the present disclosure. As shown in FIG. 8, the related hierarchical cross-connect scheme is a scheme in which optical paths are layered. An optical path is configured as a single network that includes wavelengths, wavelength bands, and fibers in that order. In contrast, the hierarchical heterogeneous routing optical network scheme of this embodiment is a scheme in which networks of different granularities are layered, as shown in FIG. 9. The hierarchical heterogeneous routing optical network scheme of this embodiment is configured as two independent networks NWs with different granularities: a wavelength cross-connect network NW and a fiber cross-connect network NW. At the same time, the hierarchical heterogeneous routing optical network scheme of this embodiment is configured to connect each network NW.

[0040] FIG. 10 is a diagram illustrating a network configuration according to the present disclosure. As shown in FIG. 10, the network configuration of this embodiment has four nodes 101 (node ​​101A to node 101D) linearly connected point-to-point. The network configuration of this embodiment may be connected in a shape such as a ring or mesh. Furthermore, the number of nodes 101 is not limited to four, and may be three or less, or four or more, as long as there is more than one. Each node 101 is composed of two layers: a WXC layer that performs switching on a wavelength-by-wavelength basis, and an FXC layer that performs switching on a fiber-by-fiber basis.

[0041] The switches of each layer are connected to the switches of two layers between adjacent nodes 101. That is, the WXC 102 of node 101A is connected to the WXC 102 and FXC 103 of node 101B. The FXC 103 of node 101A is connected to the WXC 102 and FXC 103 of node 101B. That is, related hierarchical cross-connects connect different layers within the same node 101 (there is a layer inclusion relationship), but the hierarchical cross-connect of this embodiment does not connect layers within the node 101 (there is no layer inclusion relationship).

[0042] As described above, the network configuration system of this embodiment includes a plurality of communication devices 100, each including a node 101 included in a network configuration in an optical network. The node 101 of each communication device 100 includes layers of two or more types of heterogeneous switch granularity. For example, the node 101A is connected between layers with the adjacent node 101B.

[0043] The node 101 of each communication device 100 includes a wavelength cross-connect layer and a fiber cross-connect layer. The wavelength cross-connect layer includes a wavelength cross-connect switch that performs switching on a wavelength basis. The fiber cross-connect layer includes a fiber cross-connect switch that performs switching on a fiber basis. For example, the wavelength cross-connect switch and fiber cross-connect switch of node 101A are each connected to node 101B via an optical path. In other words, the wavelength cross-connect switch and fiber cross-connect switch of node 101 of the communication device 100 are each connected to node 101 of another adjacent communication device 100 via an optical path.

[0044] Specifically, the wavelength cross connect switch of node 101A switches to connect the optical path to the wavelength cross connect switch or fiber cross connect switch of node 101B. The fiber cross connect switch of node 101A switches to connect the optical path to the wavelength cross connect switch or fiber cross connect switch of node 101B.

[0045] The wavelength cross connect switch of the node 101A does not connect an optical path to the fiber cross connect switch of the node 101A, that is, the wavelength cross connect switch of the node 101A does not switch to connect an optical path to the fiber cross connect switch of the node 101A.

[0046] <Explanation of operation> Next, the operation of optical paths in a network configuration according to the present disclosure will be described with reference to Figures 11 and 12. Figures 11 and 12 are diagrams illustrating the operation of optical paths in a network configuration according to the present disclosure. Figure 11 illustrates three optical paths 1 to 3 to explain the operation of each optical path, but this is not restrictive. Furthermore, node 101 includes a controller that performs at least one of adding and dropping optical paths 1 to 3. The controller includes, for example, a processor PRC, but is not limited to this.

[0047] First, optical path 1 is added at node 101A. Optical path 1 is dropped at node 101C. Optical path 1 is a two-hop optical path. Furthermore, optical path 2 is added at node 101A. Optical path 2 is doped at node 101D. Optical path 2 is a three-hop optical path. Furthermore, optical path 3 is added at node 101B. Optical path 3 is dropped at node 101D. Optical path 3 is a two-hop optical path. As shown in Figure 12, conceptually, optical paths without wavelength swapping bypass WXC 102.

[0048] 13 is a flowchart illustrating the operation of optical path 2 in a network configuration according to the present disclosure. FIG. 13 shows the operation of optical path 2 described above. First, the controller (e.g., processor PRC) of node 101A controls WXC 102 of node 101A to add optical path 2 (step S11). As a result, WXC 102 of node 101A adds optical path 2.

[0049] Next, the controller of the node 101A controls the WXC 102 of the node 101A to connect the optical path 2 to the FXC 103 of the node 101B (step S12). As a result, the WXC 102 of the node 101A switches so as to connect the optical path 2 to the FXC 103 of the node 101B.

[0050] Next, the controller of the node 101B controls the FXC 103 of the node 101B to connect the optical path 2 to the WXC 102 of the node 101C (step S13). As a result, the FXC 103 of the node 101B switches so as to connect the optical path 2 to the WXC 102 of the node 101C.

[0051] Next, the controller of the node 101C controls the WXC 102 of the node 101C to connect the optical path 2 to the WXC 102 of the node 101D (step S14). As a result, the WXC 102 of the node 101C switches so as to connect the optical path 2 to the WXC 102 of the node 101C.

[0052] Next, the controller of the node 101D controls the WXC 102 of the node 101D to drop the optical path 2 (step S15). As a result, the WXC 102 of the node 101D drops the optical path 2. Next, the setting is completed (step S16).

[0053] In this way, in the step of connecting layers in the communication method of this embodiment, the wavelength cross-connect switch and the fiber cross-connect switch each connect an optical path to another adjacent node 101 .

[0054] Specifically, in the step of connecting layers, the wavelength cross connect switch switches to connect the optical path 2 to a wavelength cross connect switch or a fiber cross connect switch in another adjacent node 101. Also, the fiber cross connect switch switches to connect the optical path 2 to a wavelength cross connect switch or a fiber cross connect switch in another adjacent node 101.

[0055] In the step of connecting between layers, the wavelength cross-connect switch prevents the optical path 2 from being connected to the fiber cross-connect switch of the same node 101 .

[0056] Therefore, the WXC layer and the FXC layer operate independently. Lightpath 2 can switch between layers as needed. Conceptually, as shown in Figure 12, lightpath 2, which does not require wavelength-based switching such as add, dorp, and wavelength swap, bypasses WXC 102.

[0057] Next, we will explain the simulation results using three topology models. The topology models used are COST266, a 5x5 lattice model, Spain, and JPN25. Figure 14 is a graph illustrating the port utilization rate when a certain number of optical paths according to the present disclosure are generated, with the horizontal axis representing the topology model and the vertical axis representing the port utilization rate. For each model on the horizontal axis, Figure 14 compares the case of an associated wavelength cross-connect with the case of using the network configuration according to the present disclosure.

[0058] Only WXC is used as the associated wavelength cross-connect. Therefore, the case of the associated wavelength cross-connect is normalized to 100%, and the percentage of the number of ports used for WXC and FXC is shown in the network configuration according to the present disclosure. The network configuration according to the present disclosure has a two-layer configuration of a WXC layer and an FXC layer. Therefore, there are four connection topologies: WXC-WXC, WXC-FXC, FXC-FXC, and FXC-WXC. Therefore, WXC-WXC and WXC-FXC indicate the number of ports used for WXC, and FXC-FXC and FXC-WXC indicate the number of ports used for FXC.

[0059] For example, in COST266, the number of WXC ports used is approximately 70% of that of the associated wavelength cross-connect. Therefore, the network configuration according to the present disclosure can reduce the number of WXC ports. Note that similar effects are obtained in other topology models.

[0060] FIG. 15 is a graph illustrating the number of stages through which a WXC in COST266 according to the present disclosure passes, with the horizontal axis representing the number of stages through which a wavelength path passes, and the vertical axis representing the number of optical paths normalized to the total number of optical paths being 1. As shown in FIG. 15, the routing of related wavelength paths averages 6.6 stages. On the other hand, the routing of the network configuration according to the present disclosure averages 3.9 stages. With a WXC, bandwidth narrowing may occur due to the filter effect. However, with an FXC, bandwidth narrowing is less likely to occur. Therefore, the network configuration according to the present disclosure maintains good transmission characteristics.

[0061] According to this embodiment, the node 101 includes a wavelength cross-connect layer and a fiber cross-connect layer. The node 101 is connected between adjacent nodes 101 via layers. This makes it possible to suppress the switch scale even if wavelength resources increase. Furthermore, it is possible to suppress the degradation of transmission performance even if wavelength resources increase.

[0062] <Embodiment 2> Next, a detailed description will be given of the second embodiment. Below, the network configuration method of the second embodiment will be explained by dividing it into an explanation of the configuration and an explanation of the operation.

[0063] <Configuration explanation> FIG. 16 is a diagram illustrating a network concept of a hierarchical heterogeneous routing optical network system according to the present disclosure. A second embodiment of the present disclosure is a system in which heterogeneous granularity networks are hierarchically organized. Specifically, the second embodiment of the present disclosure is configured with three independent networks NWs of different granularity: a wavelength cross-connect network NW, a wavelength band cross-connect network NW, and a fiber cross-connect network NW. At the same time, this embodiment is configured to connect the above-mentioned three networks NWs.

[0064] 17 is a diagram illustrating a network configuration according to the present disclosure. In FIG. 17, four nodes 101 (node ​​101A to node 101D) are linearly connected point-to-point. However, the network configuration of this embodiment may be connected in a ring or mesh configuration. Each node 101 is composed of three layers: a WXC layer that performs switching on a wavelength-by-wavelength basis, a WBXC layer that performs switching on a wavelength-by-waveband basis, and an FXC layer that performs switching on a fiber-by-fiber basis.

[0065] The switches of each layer are connected to switches of any layer between adjacent nodes 101. For example, the WXC 102 of node 101A is connected to the WXC 102, WBXC 104, and FXC 103 of node 101B. The WBXC 104 of node 101A is connected to the WBXC 104 of node 101B. The FXC 103 of node 101A is connected to the WXC 102 and FXC 103 of node 101B. The nodes 101B and 101C, and the nodes 101C and 101D are also connected to switches of any layer. In other words, although related hierarchical cross-connects connect different layers within the same node (there is a layer inclusion relationship), in this embodiment, inter-layer connections are not made within the node 101 (there is no layer inclusion relationship).

[0066] As described above, the network configuration system of this embodiment includes a plurality of communication devices 100, each including a node 101 included in a network configuration in an optical network. The node 101 of each communication device 100 includes three layers with different switch granularities. For example, the node 101A is connected between layers with the adjacent node 101B.

[0067] The node 101 of each communication device 100 includes a wavelength cross-connect layer, a waveband cross-connect layer, and a fiber cross-connect layer. The wavelength cross-connect layer includes a wavelength cross-connect switch that performs switching on a wavelength basis. The waveband cross-connect layer includes a waveband cross-connect switch that performs switching on a wavelength band that aggregates multiple wavelengths. The fiber cross-connect layer includes a fiber cross-connect switch that performs switching on a fiber basis. For example, the wavelength cross-connect switch, waveband cross-connect switch, and fiber cross-connect switch of node 101A are each connected to node 101B by an optical path. In other words, the wavelength cross-connect switch, waveband cross-connect layer, and fiber cross-connect switch of node 101 of the communication device 100 are each connected to node 101 of another adjacent communication device 100 by an optical path.

[0068] Specifically, the wavelength cross-connect switch of node 101A switches to connect the optical path to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch of node 101B. The wavelength band cross-connect switch of node 101A switches to connect the optical path to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch of node 101B. The fiber cross-connect switch of node 101A switches to connect the optical path to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch of node 101B.

[0069] The wavelength cross-connect switch of node 101A is not connected to the wavelength band cross-connect switch and fiber cross-connect switch of node 101A by an optical path, and the wavelength band cross-connect switch of node 101A is not connected to the fiber cross-connect switch of node 101A by an optical path.

[0070] <Explanation of operation> Next, the operation of optical paths in a network configuration according to the present disclosure will be described with reference to Figures 18 and 19. Figure 18 is a diagram illustrating the operation of optical paths in a network configuration according to the present disclosure. Figure 18 illustrates three optical paths to explain the operation of each optical path, but the present invention is not limited to this.

[0071] First, optical path 1 is added at node 101A. Optical path 1 is dropped at node 101C. Optical path 1 is a two-hop optical path. Optical path 1 is a path using a wavelength network and a fiber network. Furthermore, optical path 2 is added at node 101A. Optical path 2 is doped at node 101D. Optical path 2 is a three-hop optical path. Optical path 2 is a path using a wavelength network, a wavelength band network, and a fiber network. Furthermore, optical path 3 is added at node 101B. Optical path 3 is dropped at node 101D. Optical path 3 is a two-hop optical path. Optical path 3 is a path using a wavelength network and a wavelength band network.

[0072] 19 is a flowchart illustrating the operation of optical paths in a network configuration according to the present disclosure. FIG. 19 shows the operation of the above-mentioned optical path 2. First, the controller (e.g., processor PRC) of node 101A controls WXC 102 of node 101A to add optical path 2 (step S21). As a result, WXC 102 of node 101A adds optical path 2.

[0073] Next, the controller of node 101A controls WXC 102 of node 101A to connect optical path 2 to WBXC 104 of node 101B (step S22). As a result, WXC 102 of node 101A switches so as to connect optical path 2 to WBXC 104 of node 101B.

[0074] Next, the controller of node 101B controls the WBXC 104 of node 101B to connect optical path 2 to the FXC 103 of node 101C (step S23). As a result, the WBXC 104 of node 101B switches so as to connect optical path 2 to the FXC 103 of node 101C.

[0075] Next, the controller of the node 101C controls the FXC 103 of the node 101C to connect the optical path 2 to the WXC 102 of the node 101D (step S24). As a result, the FXC 103 of the node 101C switches so as to connect the optical path 2 to the WXC 102 of the node 101D.

[0076] Next, the controller of the node 101D controls the WXC 102 of the node 101D to drop the optical path 2 (step S25). As a result, the WXC 102 of the node 101D drops the optical path 2. Next, the setting is completed (step S26).

[0077] In this way, in the step of connecting layers in the communication method of this embodiment, the wavelength cross-connect switch, the wavelength band cross-connect switch, and the fiber cross-connect switch each connect optical paths between adjacent other nodes 101.

[0078] Specifically, in the step of connecting layers, the wavelength cross-connect switch switches to connect the optical path 2 to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch in the adjacent other node 101. Furthermore, the wavelength band cross-connect switch switches to connect the optical path 2 to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch in the adjacent other node 101. Furthermore, the fiber cross-connect switch switches to connect the optical path 2 to any one of the wavelength cross-connect switch, wavelength band cross-connect switch, and fiber cross-connect switch in the adjacent other node 101.

[0079] In the step of connecting between layers, the wavelength cross-connect switch prevents the optical path 2 from being connected to the wavelength band cross-connect switch and fiber cross-connect switch of the same node 101. Also, the wavelength band cross-connect switch prevents the optical path 2 from being connected to the fiber cross-connect switch of the same node 101.

[0080] Therefore, the WXC layer and the FXC layer operate independently. Lightpath 2 can switch between layers as needed.

[0081] According to this embodiment, the node 101 includes a wavelength cross-connect layer, a waveband cross-connect layer, and a fiber cross-connect layer. The node 101 is connected between adjacent nodes 101 through the layers. This makes it possible to suppress the switch scale even if wavelength resources increase. Furthermore, it is possible to suppress the degradation of transmission performance even if wavelength resources increase.

[0082] <Embodiment 3> Next, a detailed description will be given of the third embodiment. Below, the network configuration method of the third embodiment will be explained by dividing it into an explanation of the configuration and an explanation of the operation.

[0083] <Configuration explanation> 20 is a diagram illustrating a network configuration according to the present disclosure. In FIG. 20, two nodes 101 (node ​​101A to node 101B) are linearly connected point-to-point. However, the network configuration of this embodiment may be connected in a ring or mesh configuration. Each node 101 is configured with two layers: a WXC layer that performs switching on a wavelength-by-wavelength basis, and an FXC layer that performs switching on a fiber-by-fiber basis.

[0084] The switches in each layer are connected to the switches in the two layers between adjacent nodes 101. For example, in Fig. 20, the WXC 102 in node 101A is connected to the WXC 102 and FXC 103 in node 101B. The FXC 103 in node 101A is connected to the WXC 102 and FXC 103 in node 101B.

[0085] Furthermore, in the network configuration method of this embodiment, a wavelength conversion function is provided from the WXC 102 and FXC 103 of the preceding node 101A before the input to the WXC 102 of the node 101B. Specifically, the node 101B includes a wavelength filter 105a, a wavelength filter 105b, and a wavelength converter 106. The wavelength converter 106 is arranged in a stage preceding the wavelength cross-connect switch. The wavelength filter 105a and the wavelength filter 105b are arranged in a stage preceding the wavelength converter 106.

[0086] The wavelength filter 105a separates the input from the WXC 102 of the node 101A into wavelength components that require wavelength conversion and through wavelength components. The wavelength filter 105b separates the input from the FXC 103 of the node 101A into wavelength components that require wavelength conversion and through wavelength components. The wavelength converter 106 converts the wavelengths that require wavelength conversion that were separated by the wavelength filters 105a and 105b. The through wavelength components separated by the wavelength filters 105a and 105b are connected to the WXC 102.

[0087] <Explanation of operation> Next, the operation of optical paths in the network configuration of the third embodiment will be described with reference to Fig. 21. Fig. 21 is a diagram illustrating the operation of optical paths in the network configuration according to the present disclosure. Fig. 21 illustrates two optical paths to explain the operation of each optical path, but the present invention is not limited to this.

[0088] Lightpath 1 passes through WXC 102 of node 101A. Lightpath 1 is the path that inputs to WXC 102 of node 101B. Lightpath 2 passes through FXC 103 of node 101A. Lightpath 2 is the path that inputs to WXC 102 of node 101B.

[0089] Optical path 1 is input to wavelength filter 105a of node 101B. Optical path 1 is then separated into wavelength components that require wavelength conversion and through-wavelength components. Next, the wavelength components that require wavelength conversion separated by wavelength filter 105a are converted to the desired wavelength by wavelength converter 106 and input to WXC 102. Note that the through-wavelength components are input directly from wavelength filter 105a to WXC 102.

[0090] Optical path 2 is input to wavelength filter 105b of node 101B. The optical path 2 is then separated into wavelength components that require wavelength conversion and through-wavelength components. Next, the wavelength components that require wavelength conversion separated by wavelength filter 105b are converted to the desired wavelength by wavelength converter 106 and input to WXC 102. The through-wavelength components are input directly from wavelength filter 105b to WXC 102.

[0091] Other operations are the same as those in the first embodiment, and therefore will not be described here. This configuration makes it possible to avoid wavelength collisions between optical signals input to the WXC 102, thereby improving the efficiency of wavelength resource utilization.

[0092] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0093] Each drawing is merely an example for describing one or more embodiments. Each drawing may relate not only to one particular embodiment, but also to one or more other embodiments. As will be understood by those skilled in the art, various features or steps described with reference to any one drawing can be combined with features or steps shown in one or more other drawings to create, for example, an embodiment not explicitly shown or described. Not all features or steps shown in any one drawing are necessary to describe an exemplary embodiment, and some features or steps may be omitted. The order of steps described in any drawing may be changed as appropriate.

[0094] Some or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes.

[0095] (Appendix A1) A node included in a network configuration in an optical network, The node It includes two or more layers of heterogeneous switch granularity, The layers are connected to nodes of other adjacent communication devices. Communication equipment. (Appendix A2) The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch and the fiber cross-connect switch are connected to the nodes of the other adjacent communication devices via optical paths, respectively; 1. A communication device as described in Appendix A1. (Appendix A3) the wavelength cross connect switch switches to connect the optical path to the wavelength cross connect switch or the fiber cross connect switch in the adjacent other communication device; the fiber cross-connect switch switches the optical path so as to connect it to the wavelength cross-connect switch or the fiber cross-connect switch in the adjacent other communication device; 1. A communications device as described in Appendix A2. (Appendix A4) the wavelength cross-connect switch does not connect the fiber cross-connect switch to the optical path; 1. A communications device as described in Appendix A2. (Appendix A5) The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a wavelength band cross-connect layer including a wavelength band cross-connect switch that switches wavelength bands each including a plurality of wavelengths; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch, the wavelength band cross-connect switch, and the fiber cross-connect switch are connected to the nodes of the other adjacent communication devices by optical paths, respectively; 1. A communication device as described in Appendix A1. (Appendix A6) the wavelength cross-connect switch switches to connect the optical path to any one of the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch in the adjacent other communication device; the wavelength band cross connect switch switches to connect the optical path to any one of the wavelength cross connect switch, the wavelength band cross connect switch, and the fiber cross connect switch in the adjacent other communication device; the fiber cross-connect switch switches the optical path to connect it to any one of the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch in the adjacent other communication device; 1. A communications device as described in Appendix A5. (Appendix A7) the wavelength cross-connect switch is not connected to the wavelength band cross-connect switch and the fiber cross-connect switch, and the optical path is not connected to the wavelength band cross-connect switch and the fiber cross-connect switch; The wavelength band cross-connect switch does not connect the fiber cross-connect switch to the optical path; 1. A communications device as described in Appendix A5. (Appendix A8) The node includes a wavelength converter disposed in front of the wavelength cross-connect switch. 1. A communication device according to claim A2 or A5. (Appendix A9) the node includes a wavelength filter disposed in front of the wavelength converter; 10. A communications device as described in Appendix A8. (Appendix A10) The node includes a controller that adds and / or drops the optical path. 1. A communication device according to claim A2 or A5. (Appendix B1) a plurality of communication devices including nodes included in a network configuration in an optical network; The node of each communication device includes two or more layers of heterogeneous switch granularity; The node of the first communication device is connected between the layers of the node of the adjacent second communication device. Network configuration system. (Appendix B2) The node of each communication device a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch and the fiber cross-connect switch of the first communication device are connected to the node of the second communication device via optical paths, respectively; 10. The network configuration system of claim 1. (Appendix B3) the wavelength cross connect switch of the first communication device switches to connect the optical path to the wavelength cross connect switch or the fiber cross connect switch in the second communication device; the fiber cross-connect switch of the first communication device switches to connect the optical path to the wavelength cross-connect switch or the fiber cross-connect switch in the second communication device; 10. The network configuration system of claim B2. (Appendix B4) the wavelength cross-connect switch of the first communication device is not connected to the fiber cross-connect switch of the first communication device and the optical path; 10. The network configuration system of claim B2. (Appendix B5) The node of each communication device a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a wavelength band cross-connect layer including a wavelength band cross-connect switch that switches wavelength bands each including a plurality of wavelengths; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch of the first communication device are connected to the node of the second communication device via optical paths, respectively; 10. The network configuration system of claim 1. (Appendix B6) the wavelength cross-connect switch of the first communication device switches to connect the optical path to any one of the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch in the second communication device; the wavelength band cross connect switch of the first communication device switches to connect the optical path to any one of the wavelength cross connect switch, the wavelength band cross connect switch, and the fiber cross connect switch in the second communication device; the fiber cross-connect switch of the first communication device switches to connect the optical path to any one of the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch in the second communication device; 1. A network configuration system as described in Appendix B5. (Appendix B7) the wavelength cross-connect switch of the first communication device is not connected to the wavelength band cross-connect switch and the fiber cross-connect switch of the first communication device and the optical path; the wavelength band cross-connect switch of the first communication device is not connected to the fiber cross-connect switch of the first communication device and the optical path; 1. A network configuration system as described in Appendix B5. (Appendix B8) The node of each communication device includes a wavelength converter arranged in a stage preceding the wavelength cross-connect switch. 1. A network configuration system as described in Appendix B2 or B5. (Appendix B9) The node of each communication device includes a wavelength filter disposed in front of the wavelength converter. 10. The network configuration system of claim 8. (Appendix B10) The node of each communication device includes a controller that performs at least one of adding and dropping of the optical path. 1. A network configuration system as described in Appendix B2 or B5. (Appendix C1) A method for connecting layers between a node included in a network configuration in an optical network, the node including layers of two or more different switch granularities, and another adjacent node, Communication method. (Appendix C2) The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, In the step of connecting the layers, the wavelength cross-connect switch and the fiber cross-connect switch respectively connect optical paths between adjacent nodes; A communication method as described in Appendix C1. (Appendix C3) In the step of connecting the layers, the wavelength cross connect switch switches to connect the optical path to the wavelength cross connect switch or the fiber cross connect switch in the adjacent other node; the fiber cross-connect switch switches the optical path so as to connect it to the wavelength cross-connect switch or the fiber cross-connect switch in the adjacent other node; A communication method as described in Appendix C2. (Appendix C4) In the step of connecting the layers, the wavelength cross-connect switch prevents the fiber cross-connect switch from connecting with the optical path; A communication method as described in Appendix C2. (Appendix C5) The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a wavelength band cross-connect layer including a wavelength band cross-connect switch that switches wavelength bands each including a plurality of wavelengths; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, In the step of connecting the layers, the wavelength cross-connect switch, the wavelength band cross-connect switch, and the fiber cross-connect switch each connect an optical path between the adjacent other nodes; A communication method as described in Appendix C1. (Appendix C6) In the step of connecting the layers, the wavelength cross-connect switch switches to connect the optical path to any one of the wavelength cross-connect switch, the waveband cross-connect switch, and the fiber cross-connect switch in the adjacent other node; the wavelength band cross connect switch switches to connect the optical path to any one of the wavelength cross connect switch, the wavelength band cross connect switch, and the fiber cross connect switch in the adjacent other node; the fiber cross-connect switch switches the optical path to connect it to any one of the wavelength cross-connect switch, the wavelength band cross-connect switch, and the fiber cross-connect switch in the adjacent other node; A communication method as described in Appendix C5. (Appendix C7) In the step of connecting the layers, the wavelength cross-connect switch is not connected to the wavelength band cross-connect switch and the fiber cross-connect switch, and the optical path is not connected to the wavelength band cross-connect switch and the fiber cross-connect switch; the wavelength band cross-connect switch prevents the fiber cross-connect switch from connecting to the optical path; A communication method as described in Appendix C5. (Appendix C8) The node includes a wavelength converter disposed in front of the wavelength cross-connect switch. 1. A communication method as described in Appendix C2 or C5. (Appendix C9) the node includes a wavelength filter disposed in front of the wavelength converter; The communication method described in Appendix C8. (Appendix C10) The node includes a controller that adds and / or drops the optical path. 1. A communication method as described in Appendix C2 or C5. (Appendix D1) A communication program that causes a computer to execute a step of connecting layers between a node included in a network configuration in an optical network, the node including layers of two or more different switch granularities, and another adjacent node.

[0096] Some or all of the elements described in Appendix C2 to Appendix C9, which are dependent on Appendix C1, may also be dependent on Appendix D1 in the same dependent relationship as Appendix C1 to Appendix C9. Some or all of the elements described in any appendix may be applied to various hardware, software, recording means for recording software, systems, and methods.

[0097] Furthermore, a communication program that can be loaded into a computer to execute the above-described communication method is also within the scope of the technical concept of the embodiments. The communication program may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable medium or tangible storage medium includes random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disc (DVD), Blu-ray disc or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The information processing program may be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable medium or communication medium includes electrical, optical, acoustic, or other forms of propagated signals. [Explanation of symbols]

[0098] 1, 2, 3 Optical Path 10 Optical Fiber 11 wavelength paths 100 Communication equipment Nodes 101, 101A, 101B, 101C, and 101D 102 WXC 103 FXC 104 WBXC 105a, 105b Wavelength filters 106 wavelength converter FXC Fiber Cross Connect MMR Memory NW Network PRC Processor STR storage UI User Interface WB, WB1, WB2, WB3 wavebands WBXC Waveband Cross Connect WXC Wavelength Cross Connect

Claims

1. A node included in a network configuration in an optical network, The node Two or more layers of heterogeneous switch granularity are included; The layers are connected to nodes of other adjacent communication devices. Communication equipment.

2. The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch and the fiber cross-connect switch are connected to the nodes of the other adjacent communication devices via optical paths, respectively; The communication device according to claim 1 .

3. the wavelength cross connect switch switches to connect the optical path to the wavelength cross connect switch or the fiber cross connect switch in the adjacent other communication device; the fiber cross-connect switch switches the optical path so as to connect it to the wavelength cross-connect switch or the fiber cross-connect switch in the adjacent other communication device; The communication device according to claim 2 .

4. the wavelength cross-connect switch does not connect the fiber cross-connect switch to the optical path; The communication device according to claim 2 .

5. The node a wavelength cross-connect layer including a wavelength cross-connect switch that performs switching on a wavelength-by-wavelength basis; a wavelength band cross-connect layer including a wavelength band cross-connect switch that switches wavelength bands each including a plurality of wavelengths; a fiber cross-connect layer including a fiber cross-connect switch that performs switching on a fiber-by-fiber basis; Including, the wavelength cross-connect switch, the wavelength band cross-connect switch, and the fiber cross-connect switch are connected to the nodes of the other adjacent communication devices by optical paths, respectively; The communication device according to claim 1 .

6. The node includes a wavelength converter disposed in front of the wavelength cross-connect switch.

6. The communication device according to claim 2 or 5.

7. The node includes a controller that adds and / or drops the optical path.

6. The communication device according to claim 2 or 5.

8. a plurality of communication devices including nodes included in a network configuration in an optical network; The node of each communication device includes two or more layers of heterogeneous switch granularity; The node of the first communication device is connected between the layers of the node of the adjacent second communication device. Network configuration system.

9. A method for connecting layers between a node included in a network configuration in an optical network, the node including layers with two or more different switch granularities, and another adjacent node, Communication method.

10. A communication program that causes a computer to execute a step of connecting layers between a node included in a network configuration in an optical network, the node including layers of two or more different switch granularities, and another adjacent node.

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