Network controller and control method

Abstract

A network controller according to the present invention comprises: a setting change time acquisition unit that acquires setting change time information indicating the time required to change the setting of each of one or more node devices to be controlled; an execution cycle determination unit that determines an execution cycle for collecting quality information and controlling one or more node devices on the basis of the acquired setting change time information; a quality collection unit that collects quality information from the one or more node devices at the execution cycle determined by the execution cycle determination unit; and an analysis control unit that controls settings of each node device on the basis of the quality information on each node device collected by the quality collection unit at the execution cycle determined by the execution cycle determination unit.　

Description

[Technical Field]

[0001] The present invention relates to a network controller and a control method. [Background technology]

[0002] In conventional network control based on network quality collection, a NW (Network) controller analyzes communication quality information collected from subordinate NW nodes and changes the settings of the NW nodes based on the analysis results. FIG. 7 is a diagram showing an example configuration of a conventional communication system 1000. The communication system 1000 includes one or more NW nodes 1, a NW controller 2, and an operation system 3. The NW controller 2 includes a quality collection unit 4 and an analysis control unit 5.

[0003] The quality collection unit 4 collects quality information from each NW node 1. The analysis control unit 5 analyzes the quality information based on the quality information of each NW node 1 collected by the quality collection unit 4 and controls the settings of the NW node 1 according to the analysis results. In this case, the execution cycle of the processes performed by the quality collection unit 4 and the analysis control unit 5 is generally set in advance by the operation system 3. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Hiroshi Ou, “SLA-aware Real Time Control Technology across Optical and Mobile Networks”, Optical Fiber Communication Conference 2022. Summary of the Invention [Problem to be solved by the invention]

[0005] The optimum execution cycle for network control depends on the setting change time in NW node 1. Specifically, it is desirable that the execution cycle and the setting change time are the same length. As shown in Figure 8, if the execution cycle is longer than the setting change time, there will be a gap between the completion of a setting change in NW node 1 and the start of the next setting change, which will impair real-time performance. On the other hand, as shown in Figure 9, if the setting change time is longer than the execution cycle, the NW controller 2 will perform the next analysis and control before the setting change in NW node 1 is completed, which will take time before control can be achieved. For example, setting change-2 shown in Figure 9 cannot be performed immediately after analysis and control process-2.

[0006] As mentioned above, the optimal execution cycle for network control depends on the time it takes for the settings to be changed in the NW node 1, but the time it takes for the settings to be changed in conventional network control differs depending on the type and version of the NW node. As a result, it is not possible to set a unique cycle, and optimization requires a lot of operational work.

[0007] In view of the above circumstances, an object of the present invention is to provide a technology that can suppress operation-related work in network control. [Means for solving the problem]

[0008] One aspect of the present invention is a network controller comprising: a setting change time acquisition unit that acquires setting change time information indicating the time required to change the settings of each of one or more node devices to be controlled; an execution period determination unit that determines an execution period for collecting quality information and controlling the one or more node devices based on the acquired setting change time information; a quality collection unit that collects quality information from the one or more node devices at the execution period determined by the execution period determination unit; and an analysis control unit that controls the settings of each node device based on the quality information of each node device collected by the quality collection unit at the execution period determined by the execution period determination unit.

[0009] One aspect of the present invention is a control method that acquires setting change time information indicating the time required to change the settings of one or more node devices to be controlled, determines an execution period for collecting quality information and controlling the one or more node devices based on the acquired setting change time information, collects quality information from the one or more node devices at the determined execution period, and controls the settings of each node device based on the collected quality information of each node device at the determined execution period. [Effects of the Invention]

[0010] According to the present invention, it is possible to suppress operation-related work in network control. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of the configuration of a communication system according to a first embodiment. [Figure 2] 10 is a flowchart showing the flow of an execution period setting process performed by a NW controller in the first embodiment. [Figure 3] 10 is a flowchart showing the flow of quality collection and control processing performed by a NW controller in the first embodiment. [Figure 4] 10 is a flowchart showing the flow of an execution period setting process performed by a NW controller in the second embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example of the configuration of a communication system according to a third embodiment. [Figure 6] 11 is a flowchart showing the flow of an execution period setting process performed by a NW controller in the third embodiment. [Figure 7] FIG. 1 is a diagram illustrating an example of the configuration of a conventional communication system. [Figure 8] FIG. 1 is a diagram for explaining a conventional problem. [Figure 9] FIG. 1 is a diagram for explaining a conventional problem. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. (First embodiment) 1 is a diagram showing an example of the configuration of a communication system 100 in the first embodiment. The communication system 100 includes one or more NW nodes 10, a NW controller 20, and an operation system 30. The one or more NW nodes 10 and the NW controller 20, and the NW controller 20 and the operation system 30 are connected via transmission paths. The transmission paths may be optical transmission paths such as optical fiber, or may be electrical lines such as coaxial cables.

[0013] The NW node 10 is a device that is controlled by the NW controller 20. The NW node 10 operates according to the settings of the NW controller 20. The NW node 10 may be, for example, a forwarding device having an optical switch function and a delay measurement function, or may be a device having an edge computing function instead of an optical switch function, or may be a device having other communication functions. The NW node 10 may have a throughput measurement function instead of a delay measurement function. The NW node 10 is one aspect of a node device.

[0014] The NW node 10 reports setting change time information to the NW controller 20 in response to a request from the NW controller 20 or spontaneously when connecting to the network of the communication system 100. The setting change time information represents information related to the time required to change the setting of the NW node 10 (hereinafter referred to as "setting change time"). The setting change time is the time required from the time the NW node 10 receives a control command related to the setting change from the NW controller 20 until the setting change is completed.

[0015] The NW controller 20 is a network controller that acquires setting change time information from each NW node 10 and determines an execution period for collection and analysis control of information related to communication quality (hereinafter referred to as "quality information") based on the acquired setting change time information. The NW controller 20 collects quality information from each NW node 10 at the determined execution period and controls the setting of each NW node 10 based on the collected quality information.

[0016] The operation system 30 is a system for controlling the NW controller 20. The operation system 30 is operated by a user. The operation system 30 notifies the NW controller 20 of instructions according to user operations. The operation system 30 is one aspect of a higher-level device.

[0017] Next, a description will be given of the configuration of the NW controller 20. The NW controller 20 includes a setting change time acquisition unit 21, an execution cycle determination unit 22, a quality collection unit 23, and an analysis control unit 24.

[0018] The setting change time acquiring unit 21 acquires setting change time information of each NW node 10 connected to the NW controller 20 for each NW node 10. The setting change time acquiring unit 21 may acquire the setting change time information of each NW node 10 from the operation system 30.

[0019] The execution period determination unit 22 determines an execution period for collecting quality information and controlling each NW node 10, based on the setting change time information of each NW node 10 acquired by the setting change time acquisition unit 21. Specifically, the execution period determination unit 22 determines, as the execution period, the longest time among the longest time among the setting change time information of each NW node 10 acquired by the setting change time acquisition unit 21, the execution time required for processing by the quality collection unit 23 (hereinafter referred to as "collection execution time"), or the execution time required for processing by the analysis control unit 24 (hereinafter referred to as "control execution time").

[0020] The collection execution time and the control execution time are known information and are held in advance by the execution cycle determination unit 22. The collection execution time and the control execution time vary depending on the number of NW nodes 10 connected to the NW controller 20. Therefore, the execution cycle determination unit 22 holds information on the collection execution time and the control execution time for each number of NW nodes 10 connected to the NW controller 20. The information on the collection execution time and the control execution time may be acquired by measuring the time actually required for processing online (while processing). As described above, the execution cycle determination unit 22 decides the cycle for collecting quality information and the cycle for controlling each NW node 10, but the length of the cycle for collecting quality information and the length of the cycle for controlling each NW node 10 are the same.

[0021] The quality collecting unit 23 collects quality information from each NW node 10 at the execution period determined by the execution period determining unit 22. The quality information collected by the quality collecting unit 23 is information used for quality assurance control of the network in real time.

[0022] The analysis control unit 24 analyzes the quality information based on the quality information of each NW node 10 collected by the quality collection unit 23 at the execution period determined by the execution period determination unit 22, and controls the settings of the NW node 10 according to the analysis results.

[0023] 2 is a flowchart showing the flow of an execution period setting process performed by the NW controller 20 in the first embodiment. The execution period setting process shown in Fig. 2 is executed when the NW controller 20 is started up, when a new NW node 10 is connected, or when an instruction from an operator (for example, an instruction from the operation system 30) is received.

[0024] The setting change time acquisition unit 21 requests each NW node 10 connected to the NW controller 20 to report setting change time information. Note that the setting change time acquisition unit 21 may request only NW nodes 10 whose setting change times the NW controller 20 does not yet know to report setting change time information, or may request all NW nodes 10 to report setting change time information. In this way, the NW node 10 that has received a request from the NW controller 20 to report setting change time information reports the setting change time information to the NW controller 20.

[0025] As described above, the setting change time acquiring unit 21 collects setting change time information of each NW node 10 connected to the NW controller 20 (step S101). The setting change time acquiring unit 21 outputs the collected setting change time information of each NW node 10 to the execution period determining unit 22. Note that if the NW node 10 spontaneously reports setting change time information when connecting to the NW controller 20, the setting change time acquiring unit 21 may collect the reported setting change time information.

[0026] The execution period determination unit 22 determines an execution period for collecting quality information and controlling each NW node 10 based on the setting change time information of each NW node 10 output from the setting change time acquisition unit 21 (step S102). First, the execution period determination unit 22 compares the value of the setting change time information of each NW node 10 with the stored value of the collection execution time and the stored value of the control execution time. As a result of the comparison, the execution period determination unit 22 determines the maximum value as the execution period. For example, if the stored value of the collection execution time is the maximum value, the execution period determination unit 22 determines the value of the collection execution time as the execution period. The execution period determination unit 22 sets the determined value of the execution period in the quality collection unit 23 and the analysis control unit 24 (step S103).

[0027] Fig. 3 is a flowchart showing the flow of quality collection and control processing performed by the NW controller 20 in the first embodiment. The quality collection and control processing shown in Fig. 3 is performed at the timing of collecting quality information by the quality collector 23. The timing of collecting quality information is set in advance (for example, every 1 millisecond to 1 second, etc.).

[0028] The quality collecting unit 23 collects quality information of each NW node 10 until the period of the execution period newly set by the execution period determining unit 22 has elapsed, based on the collection timing of the quality information (step S201). The quality collecting unit 23 outputs the collected quality information of each NW node 10 to the analysis control unit 24. The analysis control unit 24 analyzes the quality information of each NW node 10 output from the quality collecting unit 23 and controls the setting of the NW node 10 according to the analysis result, based on the collection timing of the quality information until the period of the execution period newly set by the execution period determining unit 22 has elapsed (step S202).

[0029] The communication system 100 configured as described above includes the setting change time acquisition unit 21 that acquires setting change time information for each NW node 10 to be controlled by the NW controller 20, the execution period determination unit 22 that determines an execution period for collecting quality information and controlling each NW node 10 based on the setting change time information, the quality collection unit 23 that collects quality information from each NW node 10 at the execution period determined by the execution period determination unit 22, and the analysis control unit 24 that controls the setting of each NW node 10 based on the quality information of each NW node 10 collected by the quality collection unit 23 at the execution period determined by the execution period determination unit 22. This makes it possible to automatically determine and update the execution period for collection and analysis control according to each NW node 10 connected to the NW controller 20. This makes it possible to achieve high-quality network control with low operation load.

[0030] The execution period determination unit 22 of the NW controller 20 determines the execution period to be the maximum time among the setting change time information of each NW node 10 acquired by the setting change time acquisition unit 21, the collection execution time, or the control execution time. If any one of the setting change of each NW node 10, the quality information collection process, and the analysis control process has not been completed, the uncompleted process will be put on hold. By setting the maximum time as the execution period, it is possible to perform high-quality collection processes and analysis control processes while relaxing the processing performance required for each process.

[0031] (Second embodiment) In the second embodiment, a configuration will be described in which setting change time information is acquired based on the results of measurements between the NW node 10 and the NW controller 20. The system configuration of the second embodiment is the same as that of the first embodiment. The differences from the first embodiment will be described below.

[0032] In the second embodiment, the setting change time acquisition unit 21 measures the setting change time in each NW node 10 between all NW nodes 10 connected to the NW controller 20. Specifically, the setting change time acquisition unit 21 first requests each NW node 10 to change the setting, and measures the round trip time (RTT) until it receives a completion response to the request from each NW node 10. The setting change time acquisition unit 21 sets the measured RTT value of each NW node 10 as the setting change time of each NW node 10.

[0033] In addition, the setting change time acquisition unit 21 may measure the round-trip propagation delay time between the NW node 10 and the NW controller 20 using Ping or the like, separately from the RTT, and determine the setting change time as the value obtained by subtracting the round-trip propagation delay time from the RTT.

[0034] Fig. 4 is a flowchart showing the flow of the execution period setting process performed by the NW controller 20 in the second embodiment. The execution period setting process shown in Fig. 4 is executed when the NW controller 20 is started up, when a new NW node 10 is connected, or when an instruction from an operator (for example, an instruction from the operation system 30) is received. In the process shown in Fig. 4, the same processes as those in Fig. 2 are denoted by the same reference numerals as those in Fig. 2, and the description thereof will be omitted.

[0035] The setting change time acquisition unit 21 measures the setting change time of each NW node 10 connected to the NW controller 20 (step S201). For example, the setting change time acquisition unit 21 measures the RTT between each NW node 10. The setting change time acquisition unit 21 sets the measured RTT value of each NW node 10 as the setting change time of each NW node 10. The setting change time acquisition unit 21 outputs information on the setting change time of each NW node 10 based on the measurement result to the execution period determination unit 22. Thereafter, the processing from step S102 onwards is executed.

[0036] According to the communication system 100 of the second embodiment configured as described above, the setting change time acquisition unit 21 acquires setting change time information based on the results of measuring the RTT and round trip propagation delay time between the NW node 10 and the NW controller 20. This makes it possible to acquire setting change time information in a manner different from that of the first embodiment. The NW controller 20 determines an execution period based on setting change time information acquired in a manner different from that of the first embodiment, and collects quality information from each NW node 10 in the determined execution period, and controls the setting of each NW node 10 based on the collected quality information of each NW node 10. As a result, it is possible to obtain the same effects as those of the first embodiment.

[0037] (Third embodiment) In the third embodiment, a configuration will be described in which a NW controller holds setting change time information for each type of NW node and acquires setting change time information according to the type of NW node based on the held information.

[0038] 5 is a diagram showing an example of the configuration of a communication system 100a in the third embodiment. The communication system 100a includes one or more NW nodes 10a, a NW controller 20a, and an operation system 30a. The one or more NW nodes 10a and the NW controller 20a, and the NW controller 20a and the operation system 30a are connected via transmission paths. The communication system 100a differs in configuration from the first embodiment in that it includes NW nodes 10a, a NW controller 20a, and an operation system 30a instead of the NW nodes 10, the NW controller 20, and the operation system 30. The differences from the first embodiment will be described below.

[0039] The NW node 10a is a device that is controlled by the NW controller 20a. The NW node 10a operates according to the settings of the NW controller 20a. The NW node 10a may be, for example, a forwarding device having an optical switch function and a delay measurement function, or may be a device having an edge computing function instead of an optical switch function, or may be a device having other communication functions. The NW node 10a may have a throughput measurement function instead of a delay measurement function. The NW node 10a is one aspect of a node device.

[0040] The NW node 10a reports type information to the NW controller 20a in response to a request from the NW controller 20a or spontaneously when connected to the network of the communication system 100a.

[0041] The NW controller 20a acquires setting change time information corresponding to the type of the NW node 10a from the operation system 30a. The NW controller 20a creates a setting change time table by registering the acquired setting change time information corresponding to the type of the NW node 10 in a table. The setting change time table is a table in which the type of the NW node 10a and setting change time information are registered in association with each other. The NW controller 20a acquires type information from each NW node 10a and determines an execution period based on the acquired type information and the setting change time table. The NW controller 20a collects quality information from each NW node 10a at the determined execution period and controls the setting of each NW node 10a based on the collected quality information.

[0042] The operation system 30a is a system for controlling the NW controller 20. The operation system 30a notifies the NW controller 20a of setting change time information according to the type of NW node 10a. The operation system 30a is one aspect of a higher-level device. The setting change time information according to the type of NW node 10a may be obtained by an operator by performing a preliminary verification before laying the network, or if the information is published in a catalog or the like, that information may be used. As an example of information published in a catalog or the like, the following Reference 1 publishes setting change time information (described as "switching time" in Reference 1) for Polatis optical switches.

[0043] (Reference 1: Toyo Corporation, "Optical Layer 1 Switch "Polatis 6000n / 7000n Series"", [online], [Retrieved August 29, 2022], Internet<URL: https: / / www.toyo.co.jp / ict / products / detail / polatis.html> )

[0044] Next, the configuration of the NW controller 20a will be described. The NW controller 20a includes a setting change time acquisition unit 21a, an execution cycle determination unit 22, a quality collection unit 23, an analysis control unit 24, a table creation unit 25, and a table storage unit 26.

[0045] The NW controller 20a differs in configuration from the first embodiment in that it includes a setting change time acquisition unit 21a instead of the setting change time acquisition unit 21, and in that it further includes a table creation unit 25 and a table storage unit 26. The other configurations of the NW controller 20a are the same as those of the NW controller 20. Therefore, an explanation of the NW controller 20a as a whole will be omitted, and only the setting change time acquisition unit 21a, the table creation unit 25, and the table storage unit 26 will be explained.

[0046] The table creating unit 25 acquires setting change time information for each type of NW node 10a from the operation system 30a, and creates a setting change time table using the acquired setting change time information.

[0047] The table storage unit 26 stores the setting change time table created by the table creation unit 25. The table storage unit 26 is configured using a storage device such as a magnetic storage device or a semiconductor storage device.

[0048] The setting change time acquiring unit 21a acquires setting change time information of each NW node 10a connected to the NW controller 20a for each NW node 10a. Specifically, the setting change time acquiring unit 21a first requests each NW node 10a connected to the NW controller 20a to report type information. The setting change time acquiring unit 21a acquires setting change time information of each NW node 10a for each NW node 10a based on the type information acquired from each NW node 10a and the setting change time table stored in the table storage unit 26.

[0049] The setting change time acquiring unit 21a may request only NW nodes 10a whose types the NW controller 20a has not yet grasped to report type information, or may request all NW nodes 10a to report type information. In this way, the NW nodes 10a that have received a request for type information reporting from the NW controller 20a report the type information to the NW controller 20a. The setting change time acquiring unit 21a may acquire type information of each NW node 10a connected to the NW controller 20a from the operation system 30a.

[0050] Fig. 6 is a flowchart showing the flow of the execution period setting process performed by the NW controller 20a in the third embodiment. The execution period setting process shown in Fig. 6 is executed when the NW controller 20a is started up, when a new NW node 10a is connected, or when an instruction from an operator (for example, an instruction from the operation system 30a) is received.

[0051] The table creation unit 25 acquires setting change time information for each type of NW node 10a from the operation system 30a. The table creation unit 25 creates a setting change time table using the acquired setting change time information (step S401). Specifically, the table creation unit 25 creates the setting change time table by associating the setting change time information for each type of NW node 10a acquired from the operation system 30a with the type of NW node 10a. The table creation unit 25 stores the created setting change time table in the table storage unit 26.

[0052] The setting change time acquiring unit 21a collects type information of each NW node 10a connected to the NW controller 20a (step S402). The setting change time acquiring unit 21a acquires setting change time information of each NW node 10a based on the collected type information of each NW node 10a and the setting change time table stored in the table storage unit 26 (step S403). Specifically, first, the setting change time acquiring unit 21a reads out the setting change time table stored in the table storage unit 26. Then, the setting change time acquiring unit 21a refers to the type item in the read setting change time table and acquires, for each NW node 10a, the setting change time information associated with the collected type of each NW node 10a. The setting change time acquiring unit 21a outputs the acquired setting change time information of each NW node 10a to the execution period determining unit 22. Thereafter, the processing from step S102 onwards is executed.

[0053] If the NW node 10a voluntarily reports type information when connecting to the NW controller 20a, the setting change time acquisition unit 21a may collect the reported type information.

[0054] In the communication system 100a configured as described above, the setting change time acquiring unit 21a acquires type information from each NW node 10a, and acquires setting change time information for each NW node 10a by referring to the setting change time table based on the acquired type information of each NW node 10a. This makes it possible to acquire setting change time information in a manner different from that of the first embodiment. The NW controller 20a determines an execution period based on the setting change time information acquired in a manner different from that of the first embodiment, and collects quality information from each NW node 10a in the determined execution period, and controls the setting of each NW node 10a based on the collected quality information of each NW node 10a. As a result, it is possible to obtain the same effects as those of the first embodiment.

[0055] (Modification of the third embodiment) In the above-described embodiment, the configuration has been described in which the setting change time acquiring unit 21a acquires setting change time information of each NW node 10a by referring to the setting change time table. Instead of referring to the setting change time table, the setting change time acquiring unit 21a may be configured to acquire the setting change time information of each NW node 10a by inquiring of the operation system 30a about the setting change time corresponding to the type of the NW node 10a. In such a configuration, the NW controller 20a does not need to include the table creating unit 25 and the table storage unit 26. Furthermore, the NW controller 20a does not perform the process of step S401 in FIG. 6. Then, in the process of step S403, the setting change time acquiring unit 21a acquires setting change time information for each NW node 10a by inquiring of the operation system 30a about the collected setting change time corresponding to the type of each NW node 10a. With this configuration, it is not necessary to create a setting change time table in the NW controller 20a, which reduces the processing load on the NW controller 20a.

[0056] Some or all of the functional units of the NW controllers 20 and 20a described above are realized as software by a processor such as a CPU (Central Processing Unit) executing a program stored in a storage device having a non-volatile storage medium (non-transitory storage medium). The program may be recorded on a computer-readable non-transitory storage medium. Examples of computer-readable non-transitory storage media include portable media such as flexible disks, magneto-optical disks, ROMs (Read Only Memory), and CD-ROMs (Compact Disc Read Only Memory), and storage devices such as hard disks built into a computer system.

[0057] Some or all of the functional units of the NW controllers 20 and 20a described above may be realized using hardware including an electronic circuit (electronic circuit or circuitry) using, for example, an LSI (Large Scale Integrated circuit), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).

[0058] Although an embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs within the scope of the gist of the present invention. [Industrial Applicability]

[0059] The present invention can be applied to a communication system that collects network quality information. [Explanation of symbols]

[0060] 10, 10a... Network node, 20, 20a... Network controller, 30, 30a... Operation system, 21, 21a... Setting change time acquisition unit, 22... Execution cycle determination unit, 23... Quality collection unit, 24... Analysis control unit, 25... Table creation unit, 26... Table storage unit, 100, 100a... Communication system

Claims

1. a setting change time acquisition unit that acquires setting change time information indicating the time required for changing the setting of each of one or more node devices to be controlled; an execution period determination unit that determines an execution period for collecting quality information and controlling the one or more node devices based on the acquired setting change time information; a quality collection unit that collects quality information from the one or more node devices in the execution period determined by the execution period determination unit; an analysis control unit that controls settings of each node device based on the quality information of each node device collected by the quality collecting unit, at the execution period determined by the execution period determining unit; A network controller comprising:

2. the setting change time acquisition unit acquires the setting change time information by notification from a higher-level device, a request to the one or more node devices, or a spontaneous report from the one or more node devices. The network controller of claim 1 .

3. the setting change time acquisition unit acquires the setting change time information based on a result of measurement between a network controller and the one or more node devices. The network controller of claim 1 .

4. the setting change time acquisition unit further acquires information relating to the type of the one or more node devices, and acquires the setting change time information by referring to a table in which the setting change time information for each type of node device is associated based on the acquired information relating to the type of the one or more node devices, or by inquiring of a higher-level device about the setting change time corresponding to the type of node device. The network controller of claim 1 .

5. a table creation unit that acquires setting change time information for each type of node device, and creates the table by using the acquired setting change time information to associate and register the setting change time information for each type of node device, The network controller of claim 4 .

6. the execution cycle determination unit determines, as the execution cycle, the maximum time among the maximum time of the setting change time information acquired by the setting change time acquisition unit, the execution time required for processing by the quality collection unit, or the execution time required for processing by the analysis control unit. A network controller according to any one of claims 1 to 5.

7. Acquire setting change time information indicating the time required for changing the setting of each of the one or more node devices to be controlled; determining an execution period for collecting quality information and controlling the one or more node devices based on the acquired setting change time information; collecting quality information from the one or more node devices in the determined execution period; A control method for controlling the setting of each node device based on the collected quality information of each node device in the determined execution period.

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