Controller and control method

Abstract

A control device comprising: a collection unit that acquires cooperation information from a plurality of communication stations accommodating one or more terminals; and an analysis unit that determines one or more communication stations to enter sleep mode from among the plurality of communication stations on the basis of the cooperation information, and causes sleep control to be executed for the determined one or more communication stations by another device or by some functions of another device on the basis of the determined one or more communication stations.　

Description

Control device and control method

[0001] The present invention relates to a control device and a control method.

[0002] In conventional communication systems that perform wireless communication between terminals and base stations, each base station calculates the throughput and automates the system to enter sleep mode when the throughput exceeds a threshold, thereby saving power. In such communication systems, terminals connected to a sleeping base station are instructed to hand over to the base station with the highest throughput. This allows the terminal to continue communicating.

[0003] However, in the above communication system, if a terminal connected to a sleep base station is handed over to a base station that already has many terminals connected, it may lead to a deterioration in communication quality. Furthermore, in the above communication system, each base station autonomously decides whether or not to enter sleep mode, so overall optimization may not be possible, potentially limiting the effectiveness of power saving.

[0004] Therefore, a communication system has been proposed that collects information such as the number of terminals accommodated by each distributed station and the traffic volume of each distributed station as coordination information from each distributed station that makes up each base station, and puts the distributed stations to sleep based on the collected coordination information (see, for example, Patent Document 1). In the communication system described in Patent Document 1, a distributed station to which multiple terminals will be aggregated is determined based on the coordination information, and the multiple terminals are aggregated to the determined distributed station. Then, other distributed stations that have lost connections are put into sleep mode. This makes it possible to save power in other distributed stations that have lost connections.

[0005] International Publication No. 2023 / 223416

[0006] In typical communication systems, relay devices are provided within the network to relay signals between terminals such as transmission devices and transceivers and distributed stations. In the communication system described in Patent Document 1, sleep control was performed on the distributed stations themselves, but other devices such as relay devices that were not in use remained active. Therefore, there is room for further improvement in power saving in the communication system described in Patent Document 1. This problem is not limited to communication systems that connect to terminals wirelessly, but also occurs in communication systems that connect to terminals via wires.

[0007] In view of the above circumstances, the present invention aims to provide a technology that can improve the effectiveness of power saving.

[0008] One aspect of the present invention is a control device comprising: a collection unit that acquires cooperation information from a plurality of communication stations accommodating one or more terminals; and an analysis unit that determines one or more communication stations to be put into sleep mode from among the plurality of communication stations based on the cooperation information, and causes another device or a part of the functions provided by the other device, and the determined one or more communication stations to execute sleep control.

[0009] One aspect of the present invention is a control method that acquires cooperation information from a plurality of communication stations accommodating one or more terminals, determines one or more communication stations to be put into sleep mode from among the plurality of communication stations based on the cooperation information, and, based on the determined one or more communication stations, causes another device or some of the functions provided by the other device to execute sleep control for the determined one or more communication stations.

[0010] This invention makes it possible to improve the effectiveness of power saving.

[0011] This is a diagram illustrating the overall configuration and processing overview of the mobile network system in the first embodiment. This is a diagram showing an example configuration of the mobile network system in the first embodiment. This is a flowchart showing an example of the sleep processing flow executed by the management control device in the first embodiment. This is a flowchart showing an example of the sleep wake-up processing flow executed by the management control device in the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 1 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 2 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 3 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 4 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 5 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 6 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 7 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 8 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 9 of the first embodiment. This is a diagram showing an example configuration of the mobile network system in Modification 10 of the first embodiment. This is a diagram illustrating the overall configuration and processing overview of the mobile network system in the second embodiment. This is a diagram showing an example configuration of the mobile network system in the second embodiment. This is a flowchart illustrating an example of the sleep processing flow performed by the management control device in the second embodiment. This is a flowchart illustrating an example of the wake-up processing flow performed by the management control device in the second embodiment. This is a diagram illustrating the overall configuration and processing overview of the mobile network system in the third embodiment. This is a diagram illustrating an example of the configuration of the mobile network system in the third embodiment. This is a flowchart illustrating an example of the sleep processing flow performed by the management control device in the third embodiment. This is a flowchart illustrating an example of the wake-up processing flow performed by the management control device in the third embodiment. This is a diagram illustrating the overall configuration and processing overview of the wired network system in the fourth embodiment. This is a diagram illustrating an example of the configuration of the wired network system in the fourth embodiment.This flowchart shows an example of the sleep process flow executed by the management control device in the fourth embodiment. This flowchart shows an example of the wake-up process flow executed by the management control device in the fourth embodiment. This diagram shows another example of the configuration of the wired network system in the fourth embodiment.

[0012] One embodiment of the present invention will be described below with reference to the drawings.

[0013] (Outline of the First Embodiment) Figure 1 is a diagram illustrating the overall configuration and processing overview of the mobile network system in the first embodiment. First, the overall configuration of the mobile network system in the first embodiment will be described. The mobile network system is an example of a communication system. The mobile network system is, for example, a fifth-generation mobile communication system (hereinafter referred to as "5G"). The mobile network system comprises a radio station 12, a transfer device 13, an optical transfer device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20. In the following description, the direction from the terminal 11 to the server 18 will be described as the uplink direction, and the direction from the server 18 to the terminal 11 will be described as the downlink direction.

[0014] The following connections are made between the transfer device 13 and the optical transfer device 14, between the optical transfer device 14 and the distributed station 15, between the distributed station 15 and the aggregation station 16, between the aggregation station 16 and the core device 17, and between the core device 17 and the server 18, using optical fibers to transmit optical signals. The following connections are made between the transfer device 13 and the management control device 20, between the optical transfer device 14 and the management control device 20, and between the distributed station 15 and the management control device 20, using either control lines (e.g., electric wires) or optical fibers to transmit control signals.

[0015] The example shown in Figure 1 illustrates a mobile network system comprising two radio stations 12-1 to 12-2, one transmission device 13, two optical transmission devices 14-1 to 14-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13, optical transmission devices 14, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system is not particularly limited.

[0016] In Figure 1, the transfer device 13 and optical transfer device 14 are arranged in the order of transfer device 13 and optical transfer device 14, with respect to the direction from the radio station 12 to the server 18 (upstream direction). However, the arrangement of the transfer device 13 and optical transfer device 14 is not limited to this. For example, they may be arranged in the order of transfer device 13, optical transfer device 14, and transfer device 13, with respect to the direction from the radio station 12 to the server 18 (upstream direction), or in the order of optical transfer device 14 and transfer device 13, or only optical transfer device 14 may be arranged, or multiple optical transfer devices 14 may be arranged in a series (for example, in the order of optical transfer device 14-1, optical transfer device 14-2, ...).

[0017] The radio station 12 is equipped with one or more antennas and performs wireless communication with one or more terminals 11. For example, the radio station 12 receives an uplink signal transmitted from one or more terminals 11 and transmits the received uplink signal to the destination distributed station 15 via the transfer device 13 and the optical transfer device 14. The radio station 12 transmits the downlink signal received via the transfer device 13 and the optical transfer device 14 to one or more terminals 11.

[0018] If the radio station 12 is equipped with multiple antennas, the radio station 12 may perform wireless communication with one or more terminals 11 by beamforming. The radio station 12 is, for example, a Radio Unit (RU) in the 5G communication standard.

[0019] The transmission device 13 is provided between the radio station 12 and the optical transmission device 14. The transmission device 13 is, for example, a router or L2 switch that has the function of transmitting optical signals. The transmission device 13 converts the uplink signal transmitted from the radio station 12 into an optical signal and transmits it to the destination optical transmission device 14, or converts the optical signal transmitted from the optical transmission device 14 into an electrical signal (downlink signal) and transmits it to the destination radio station 12.

[0020] The transfer device 13 controls the optical path according to control instructions (hereinafter referred to as "optical path control information") transmitted from the management control device 20. For example, the optical path control performed by the transfer device 13 includes switching optical paths and forming new optical paths. By controlling the optical path, the transfer device 13 controls the connection between the radio station 12 and the optical transfer device 14. For example, when the transfer device 13 receives optical path control information transmitted from the management control device 20, it performs a switch so that the optical path is connected between the radio station 12, which is the destination of the optical path switch, and the optical transfer device 14.

[0021] Furthermore, as described above, the transfer device 13 includes a plurality of optical transceivers (not shown in Figure 1) for transmitting and receiving optical signals with at least the optical transfer device 14. The optical transceivers have functions such as receiving an uplink signal transmitted from the radio station 12, converting the received uplink signal into an optical signal and transferring it to the optical transfer device 14, and receiving an optical signal transmitted from the optical transfer device 14, converting the received optical signal into an electrical signal and transferring it to the radio station 12.

[0022] Furthermore, the transfer device 13 transitions the optical transceiver specified by the sleep instruction to a sleep state in accordance with the sleep instruction transmitted from the management control device 20. The sleep state is a state in which power saving can be achieved by stopping some functions or the entire device. The optical transceiver specified by the sleep instruction is, for example, an optical transceiver that will no longer be used due to switching of the optical path. An optical transceiver that will no longer be used is an optical transceiver that does not need to be in an usable state and is an optical transceiver that is subject to sleep mode.

[0023] Furthermore, if the optical transceiver identified by the sleep instruction transmitted from the management control device 20 is an optical transceiver that communicates with the optical transfer device 14-1, the transfer device 13 puts the optical transceiver that communicates with the optical transfer device 14-1 into a sleep state. In this way, the transfer device 13 puts the optical transceiver that will no longer be used due to the switching of the optical path into a sleep state.

[0024] Furthermore, the transfer device 13 releases the sleep state of the optical transceiver specified by the sleep release instruction in accordance with the h transmitted from the management control device 20. Releasing the sleep state means activating the stopped function (the function that is in sleep state) to make it usable. The optical transceiver specified by the sleep release instruction is, for example, an optical transceiver used by switching optical paths. The optical transceiver used is an optical transceiver that needs to be made usable and is the optical transceiver to be released from sleep.

[0025] For example, if the optical transceiver identified by the sleep-release instruction transmitted from the management control device 20 is an optical transceiver that communicates with the optical transfer device 14-1, the transfer device 13 will release the optical transceiver that communicates with the optical transfer device 14-1 from the sleep state among the multiple optical transceivers. In this way, the transfer device 13 transitions the optical transceiver used by switching the optical path from the sleep state to the active state among the multiple optical transceivers. The transfer device 13 is one embodiment of other devices and relay devices.

[0026] The optical transfer device 14 is provided between the transfer device 13 and the distributed station 15. The optical transfer device 14 is, for example, an optical switch or a ROADM (Reconfigurable Optical Add-Drop Multiplexer). The optical transfer device 14 transfers the optical signal transferred from the transfer device 13 to the destination distributed station 15, or transfers the optical signal transmitted from the distributed station 15 to the transfer device 13.

[0027] The optical transfer device 14 controls the optical path according to the optical path control information transmitted from the management control device 20. For example, the optical path control performed by the optical transfer device 14 includes switching optical paths and forming new optical paths. By controlling the optical path, the optical transfer device 14 controls the connection between the transfer device 13 and the distributed station 15. For example, when the optical transfer device 14 receives optical path control information transmitted from the management control device 20, it performs a switch so that the optical path is connected between the transfer device 13 and the distributed station 15, which are the destinations of the optical path switch.

[0028] Further, the optical transfer device 14 shifts to the sleep state in accordance with the sleep instruction transmitted from the management control device 20. Different from the transfer device 13, when the optical transfer device 14 receives the sleep instruction, the optical transfer device 14 itself shifts to the sleep state. This is because the distributed station 15 connected to the optical transfer device 14 shifts to the sleep state, and the optical transfer device 14 itself becomes unused due to the switching of the optical path.

[0029] Further, the optical transfer device 14 releases the sleep state in accordance with the sleep release instruction transmitted from the management control device 20. Different from the transfer device 13, when the optical transfer device 14 receives the sleep instruction, the optical transfer device 14 releases its own sleep state. This is because the distributed station 15 connected to the optical transfer device 14 in the sleep state releases the sleep state, and the optical transfer device 14 itself is used due to the switching of the optical path. The optical transfer device 14 is an aspect of other devices and relay devices.

[0030] As described above, the transfer device 13 and the optical transfer device 14 are devices that control the optical path for connecting the radio station 12 and the distributed station 15.

[0031] The distributed station 15 receives the upstream signal transmitted by one or more radio stations 12 as an optical signal via the transfer device 13 and the optical transfer device 14. The distributed station 15 transmits the downstream signal to one or more radio stations 12 as the destination via the transfer device 13 and the optical transfer device 14. Note that the upstream signal transmitted by one or more radio stations 12 is the signal transmitted by the terminal 11, and the downstream signal is the signal destined for the terminal 11.

[0032] Each distributed station 15 shifts to the sleep state in accordance with the sleep instruction transmitted from the management control device 20. Each distributed station 15 releases the sleep state in accordance with the sleep release instruction transmitted from the management control device 20. The distributed station 15 is, for example, a DU (Distributed Unit) in the 5G communication standard. The information acquired by the management control device 20 from the distributed station 15 is referred to as cooperation information. The cooperation information in the first embodiment is information regarding each distributed station 15, and is, for example, information indicating the communication state between each distributed station 15 and the terminal 11.

[0033] The cooperation information in the first embodiment includes, for example, information on the traffic volume of each distributed station 15. Hereinafter, the information on the traffic volume is referred to as traffic information. The traffic information is, for example, as described in DCI (Downlink Control Information) or O-RAN CTI (O-RAN.WG4.CTI-TCP.0-v01.00). O-RAN CTI intends to refer to scheduling information.

[0034] The aggregation station 16 aggregates the uplink signals transmitted by each distributed station 15 and transmits them to the core device 17. The aggregation station 16 transmits the downlink signal transmitted from the core device 17 to the target distributed station 15. The aggregation station 16 is, for example, a CU (Centralized Unit) in the 5G communication standard.

[0035] The core device 17 executes signal processing on the uplink signal aggregated by the aggregation station 16. The core device 17 transmits the signal obtained as a result of executing the signal processing on the uplink signal to the server 18. The core device 17 is an aspect of a higher-level device.

[0036] The core device 17 performs predetermined signal processing on the signal received from the server 18. The core device 17 transmits the signal obtained as a result of executing the signal processing on the signal received from the server 18 to the aggregation station 16 as a downlink signal. The signal processing is, for example, the transfer of user data in the UPF (User Plane Function) of the 5G core network.

[0037] The server 18 transmits the signal transmitted from the core device 17 to the external network. The server 18 transmits the signal received from the external network to the core device 17.

[0038] The management control device 20 is a device that manages the entire mobile network system. The management control device 20 acquires coordination information from each distributed station 15. When acquiring coordination information from each distributed station 15, the management control device 20 uses a coordination interface. The coordination interface is an interface that connects the management control device 20 to each distributed station 15. Based on the acquired coordination information, the management control device 20 determines whether or not optical path control and sleep control are necessary.

[0039] For example, the management control device 20 may determine that optical path control is necessary when it determines that sleep control is possible. The management control device 20 performs optical path control processing and sleep control processing when it determines that sleep control is necessary. Optical path control processing is the process of causing the transfer device 13 and optical transfer device 14 to switch optical paths between the radio station 12 and the distributed station 15 or to generate optical paths. Sleep control processing is the process of causing the device subject to sleep control to perform sleep or to release the sleep state. In the first embodiment, the devices subject to sleep control are the multiple optical transceivers provided in the transfer device 13, the optical transfer device 14, and the distributed station 15.

[0040] During optical path control processing, the management control device 20 determines whether there is an optical transceiver or optical transfer device 14 in the transfer device 13 that will not be used for signal transfer after the optical path is switched. If there is an optical transceiver or optical transfer device 14 in the transfer device 13 that will not be used for signal transfer after the optical path is switched, the management control device 20 determines that the unused optical transceiver or optical transfer device 14 in the transfer device 13 is subject to sleep control. The management control device 20 then sends a sleep instruction to the transfer device 13 or optical transfer device 14 that has an unused optical transceiver. If there is no optical transceiver or optical transfer device 14 in the transfer device 13 that will not be used for signal transfer after the optical path is switched, the management control device 20 does not determine that the optical transceiver and optical transfer device 14 in the transfer device 13 are subject to sleep control.

[0041] Furthermore, during optical path control processing, the management control device 20 determines whether there is an optical transceiver in a sleep state or an optical transfer device 14 in a sleep state, which are included in the transfer device 13 used for signal transfer after the optical path is switched. If there is an optical transceiver in a sleep state or an optical transfer device 14 in a sleep state, which are included in the transfer device 13 used for signal transfer after the optical path is switched, the management control device 20 determines that either the optical transceiver in a sleep state or the optical transfer device 14 in a sleep state, which are included in the transfer device 13 used, are subject to sleep control.

[0042] The control device 20 then sends a sleep-release instruction to the transfer device 13 or the optical transfer device 14 equipped with the optical transceiver in sleep mode that is to be used. If, after the optical path switching, the transfer device 13 used for signal transfer does not have an optical transceiver in sleep mode or an optical transfer device 14 in sleep mode, the control device 20 does not determine that the optical transceiver in sleep mode and the optical transfer device 14 in sleep mode are targets for sleep control. The control device 20 is one embodiment of the control device.

[0043] Next, an overview of the processing of the mobile network system in the first embodiment will be described. The upper diagram of Figure 1 shows the connection status of the mobile network system before optical path switching, and the lower diagram of Figure 1 shows the connection status of the mobile network system after optical path switching. In the upper diagram of Figure 1, it is assumed that radio station 12-1 is connected to distributed station 15-1, and radio station 12-2 is connected to distributed station 15-2.

[0044] The management control device 20 determines, based on the coordination information collected from each distributed station 15, that sleep control is possible if one distributed station 15 can accommodate the traffic of the other distributed stations 15. In other words, based on the coordination information collected from each distributed station 15, the management control device 20 performs optical path control processing and sleep control processing if one distributed station 15 can accommodate the traffic of the other distributed stations 15. In this way, by accommodating the traffic of the other distributed stations 15 to one distributed station 15, the other distributed stations 15 whose traffic has ceased can be put into sleep mode.

[0045] When the management control device 20 performs optical path control processing, it instructs the transfer device 13 and the optical transfer device 14 to switch optical paths. The management control device 20 determines the route after the optical path switch during the optical path control processing. Therefore, the management control device 20 can identify the optical transceivers and optical transfer devices 14 equipped with the transfer device 13 that will not be used after the optical path switch in the section between the radio station 12 and the distributed station 15.

[0046] For example, as shown in the lower diagram of Figure 1, the management control device 20 determines that distributed station 15-1 can be put into sleep mode if distributed station 15-2 can accommodate all of the traffic from distributed station 15-1. Then, in the optical path control processing, the management control device 20 transmits optical path control information to the transfer device 13 instructing it to switch the path from transfer device 13 to optical transfer device 14-1 to the path from transfer device 13 to optical transfer device 14-2.

[0047] As a result, in the path after the optical path is switched, the optical transceiver connected to the optical transceiver 14-1 among the multiple optical transceivers provided by the transceiver 13, and the optical transceiver 14-1 itself, will not be used. Therefore, the management control device 20 determines that in the path after the optical path is switched, the optical transceiver connected to the optical transceiver 14-1 among the multiple optical transceivers provided by the transceiver 13, and the optical transceiver 14-1 itself, will not be used. The management control device 20 then determines that the optical transceiver connected to the optical transceiver 14-1 and the optical transceiver 14-1 itself are also capable of sleep control.

[0048] The transfer device 13 switches the optical path between the radio station 12 and the optical transfer device 14 in accordance with the optical path switching instruction from the management control device 20. For example, the transfer device 13 switches the optical path to connect radio station 12-1 and optical transfer device 14-2. This allows the transfer device 13 to switch the optical path so that the uplink signal transmitted from radio station 12-1, which was connected to optical transfer device 14-1, can be transferred to the distributed station 15-2. As a result, the transfer device 13 transfers the uplink signals transmitted from radio stations 12-1 and 12-2, respectively, to optical transfer device 14-2.

[0049] In addition, the optical transmission device 14 may need to switch optical paths. In such cases, the management control device 20 will also send an instruction to the optical transmission device 14 to switch optical paths. After the transmission device 13 and the optical transmission device 14 have completed switching optical paths, they will notify the management control device 20 that the optical path switching is complete. Since the destination of the terminal 11 will change due to the optical path switching, the management control device 20 may instruct the distributed station 15, which is the target of the optical path switching, to change its connection.

[0050] When the management control device 20 receives notification of completion of optical path switching from the device to be switched (for example, the transfer device 13 or the optical transfer device 14), it sends a sleep permission notification to the devices that can enter a sleep state. In the example shown in the lower part of Figure 1, the management control device 20 determines that the distributed station 15-1, the optical transfer device 14-1, and the optical transceiver of the transfer device 13 connected to the optical transfer device 14-1 are devices that can enter a sleep state. Therefore, the management control device 20 sends a sleep permission notification to the transfer device 13, the optical transfer device 14-1, and the distributed station 15-1. The sleep permission notification is a signal that includes instructions to put the devices subject to sleep control into a sleep state. The sleep permission notification that the management control device 20 sends to the transfer device 13 includes information indicating the optical transceiver to be put into sleep. As a result, the devices subject to sleep control enter a sleep state.

[0051] The lower diagram of Figure 1 shows an example in which radio stations 12-1 to 12-2 are connected to distributed station 15-2, and the optical transceivers in distributed station 15-1, optical transfer device 14-1, and transfer device 13 connected to optical transfer device 14-1 are in a sleep state. Based on the coordination information collected from each distributed station 15, the management control device 20 causes devices that are capable of entering a sleep state to enter a sleep state by connecting terminals 11 connected to distributed stations 15 that are capable of entering a sleep state to other distributed stations 15.

[0052] By putting distributed station 15 into sleep mode, the optical path leading to distributed station 15 is switched. For example, if terminal 11 connected to distributed station 15-1, which can be put into sleep mode, is to be connected to distributed station 15-2, the optical path leading to distributed station 15-1 will be switched to lead to distributed station 15-2. In this way, by putting distributed station 15 into sleep mode, the optical path leading to distributed station 15 is switched. Hereafter, the distributed station 15 that is the source of the optical path switch will be referred to as the source distributed station, and the distributed station 15 that is the destination of the optical path switch will be referred to as the destination distributed station.

[0053] (Details of the First Embodiment) Figure 2 is a diagram showing an example configuration of the mobile network system 100 in the first embodiment. The mobile network system 100 in the first embodiment includes a radio station 12, a transmission device 13, an optical transmission device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20. The radio station 12, optical transmission device 14, distributed station 15, aggregation station 16, core device 17, and server 18 have been explained in Figure 1, so their explanation will be omitted here.

[0054] The transfer device 13 includes a first optical transceiver 131 and a second optical transceiver 132. In Figure 2, for the sake of simplicity, the transfer device 13 is shown to have a configuration comprising two first optical transceivers 131-1 to 131-2 and two second optical transceivers 132-1 to 132-2, but the number of first optical transceivers 131 and second optical transceivers 132 is not particularly limited.

[0055] The first optical transceiver 131 transmits and receives signals between the radio station 12 and the second optical transceiver 132. The first optical transceiver 131 forwards the uplink signal transmitted from the radio station 12 to the second optical transceiver 132, which is the forwarding destination. The first optical transceiver 131 also forwards the downlink signal transmitted from the second optical transceiver 132 to the destination radio station 12.

[0056] The second optical transceiver 132 transmits and receives signals between the optical transfer device 14 and the first optical transceiver 131. The second optical transceiver 132 converts the uplink signal transmitted from the first optical transceiver 131 into an optical signal and transfers it to the destination optical transfer device 14. The second optical transceiver 132 also converts the optical signal transmitted from the optical transfer device 14 into a downlink signal (electrical signal) and transfers it to the destination first optical transceiver 131.

[0057] In the example shown in Figure 2, the first optical transceiver 131-1 and the second optical transceiver 132-1 are connected, and the first optical transceiver 131-2 and the second optical transceiver 132-2 are connected. The transfer device 13 switches the connection between the first optical transceiver 131 and the second optical transceiver 132 based on optical path control information transmitted from the management control device 20. For example, as shown in Figure 1, when switching the optical path so that the uplink signal transmitted from the radio station 12-1 is transferred to the distributed station 15-2 via the optical transfer device 14-2, the transfer device 13 switches to connect the first optical transceiver 131-1 and the second optical transceiver 132-2. As a result, the uplink signal transmitted from the radio station 12-1 is transferred to the optical transfer device 14-2 via the first optical transceiver 131-1 and the second optical transceiver 132-2.

[0058] [Configuration of the Management Control Device 20] Next, the configuration of the management control device 20 in the first embodiment will be described. The management control device 20 comprises a collection unit 21, an analysis unit 22, and a control unit 23. The collection unit 21 comprises an acquisition unit 211. The acquisition unit 211 acquires various types of information. For example, the acquisition unit 211 collects cooperation information from the distributed stations 15 at predetermined intervals or at arbitrary timings. The acquisition unit 211 collects traffic information from each distributed station 15 as cooperation information.

[0059] The analysis unit 22 comprises an information storage unit 221 and an information analysis unit 222. The information storage unit 221 records the cooperation information collected by the acquisition unit 211 in a predetermined storage device. The information analysis unit 222 analyzes the communication status between each distributed station 15 and the terminal 11 based on the cooperation information. Specifically, the information analysis unit 222 determines whether optical path control and sleep control are necessary based on the cooperation information.

[0060] For example, the information analysis unit 222 determines that it will perform optical path control processing and sleep control processing if all terminals 11 accommodated by one distributed station 15 can be accommodated by any of the distributed stations 15. In this case, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep instruction. The optical path control instruction is an instruction to request an optical path switch, and includes, for example, information indicating the source distributed station and information indicating the destination distributed station. The sleep instruction is an instruction to send a sleep permission notification, and includes, for example, information indicating the device to be put into sleep mode.

[0061] When the information analysis unit 222 determines that it will perform optical path control processing and sleep control processing, it determines the optical path control section. Specifically, the information analysis unit 222 may determine the optical path control section as the section in which switching of the optical path is required when the distributed station 15 that is to be put into sleep mode is put into sleep mode during sleep control processing. Then, the information analysis unit 222 identifies the first optical transceiver 131, the second optical transceiver 132, or the optical transfer device 14 that will no longer be used after the optical path switching in the determined optical path control section.

[0062] If there are any first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 that will no longer be used after the optical path switching, the information analysis unit 222 determines these first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 that will no longer be used to be put into sleep mode. If there are no first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 that will no longer be used after the optical path switching, the information analysis unit 222 does not perform any special processing.

[0063] Furthermore, the information analysis unit 222 determines that if the traffic volume of a certain distributed station 15 exceeds a threshold, it will perform optical path control processing and sleep control processing. In this case, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep release instruction. The sleep release instruction is an instruction to release the sleep state and includes information indicating, for example, the distributed station 15 to be released from sleep, the optical transmission device 14, and the optical transceiver provided in the transmission device 13.

[0064] When the information analysis unit 222 determines that it will perform optical path control processing and sleep control processing, it determines the optical path control section. Specifically, the information analysis unit 222 may determine the section in which switching of the optical path is required when the sleep of the distributed station 15 that is to be woken up in the sleep control processing is to be determined as the optical path control section. Then, the information analysis unit 222 identifies the first optical transceiver 131, the second optical transceiver 132, or the optical transfer device 14 that are in sleep mode and will be used after switching the optical path in the determined optical path control section.

[0065] If there are any first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 in a sleep state that will be used after the optical path is switched, the information analysis unit 222 determines which of the first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 in a sleep state that will be used to be woken up. If there are no first optical transceivers 131, second optical transceivers 132, or optical transfer devices 14 in a sleep state that will be used after the optical path is switched, the information analysis unit 222 does not perform any special processing.

[0066] The control unit 23 includes an optical path control unit 231 and a sleep control unit 232. The optical path control unit 231 determines the source distributed station and the destination distributed station based on the results of the analysis by the information analysis unit 222. For example, the optical path control unit 231 determines the source distributed station based on information indicating the source distributed station included in the control information notified by the information analysis unit 222. For example, the optical path control unit 231 determines the destination distributed station based on information indicating the destination distributed station included in the control information notified by the information analysis unit 222. The optical path control unit 231 holds information on the radio station 12 connected to the distributed station 15.

[0067] The optical path control unit 231 transmits optical path control information, including information indicating the determined switching destination distributed station, to the transfer device 13 and the optical transfer device 14. This instructs the transfer device 13 and the optical transfer device 14 to switch the optical path.

[0068] Based on the results of the analysis by the information analysis unit 222, the sleep control unit 232 causes the device subject to sleep control to either enter sleep mode or exit sleep mode.

[0069] [Sleep Processing] Figure 3 is a flowchart showing an example of the sleep processing flow performed by the management control device 20 in the first embodiment. Here, we will explain using the example of two distributed stations 15 (for example, distributed stations 15-1 to 15-2) and using traffic information as the cooperation information. Furthermore, for the sake of simplicity, we will assume that the connection configuration of each device is as shown in Figure 2.

[0070] The information analysis unit 222 acquires the latest cooperation information for each distributed station 15 stored in the information storage unit 221 (step S101). In the management control device 20, cooperation information is collected at predetermined intervals or at arbitrary timings until the process shown in Figure 3 is executed. Therefore, the information storage unit 221 stores cooperation information for each distributed station 15 at predetermined intervals or at arbitrary timings. When the process shown in Figure 3 is started, the information analysis unit 222 acquires the latest cooperation information for each distributed station 15 at the start of the process shown in Figure 3.

[0071] The information analysis unit 222 calculates the traffic volume for each of the distributed stations 15-1 to 15-2 based on the latest coordinate information for each distributed station 15 that it has acquired. Then, the information analysis unit 222 sorts the distributed stations 15-1 to 15-2 in ascending order of the calculated traffic volume (step S102).

[0072] The information analysis unit 222 determines the traffic volume to be added to A (step S103). Traffic volume to be added to A is, for example, the distributed station 15 with the lowest traffic volume. For example, here we will designate the distributed station 15 with the lowest traffic volume as distributed station 15-1. Next, the information analysis unit 222 determines the traffic volume to be added to B (step S104). Traffic volume to be added to B is, for example, the distributed station 15 with the second lowest traffic volume. For example, here we will designate the distributed station 15 with the second lowest traffic volume as distributed station 15-2. The information analysis unit 222 adds the traffic volume of traffic volume to A and the traffic volume of B to obtain the traffic volume to be added value T. ｔｏｔａｌ Calculate (step S105).

[0073] The information analysis unit 222 calculates the traffic volume sum value T.ｔｏｔａｌ The traffic volume sum T is compared with the calculated traffic volume sum T. Here, the threshold is a value for control decision, and may be the same value for each distributed station 15, or it may be a different value for each distributed station 15. The threshold may be calculated by the information analysis unit 222 based on the cooperation information and recorded in the information storage unit 221, or it may be stored in advance by the information analysis unit 222 for each distributed station 15. If the threshold for each distributed station 15 is recorded in the information storage unit 221, the information analysis unit 222 may read and use the threshold recorded in the information storage unit 221. The information analysis unit 222 calculates the traffic volume sum T. ｔｏｔａｌ This is then compared with the threshold value of the distributed station 15 corresponding to the summation target A.

[0074] The information analysis unit 222 calculates the traffic volume sum value T. ｔｏｔａｌ However, it is determined whether or not it is greater than the threshold (step S106). The information analysis unit 222 determines whether the traffic volume sum value T ｔｏｔａｌ However, if it is determined that the amount is not greater than the threshold (step S106-NO), the information analysis unit 222 adds the smallest traffic amount among the traffic amounts that have not been added, thereby creating a new traffic amount addition value T ｔｏｔａｌ Calculate (step S107).

[0075] Subsequently, the information analysis unit 222 executes the process in step S106 again. In this case, the information analysis unit 222 calculates the newly calculated traffic volume sum value T. ｔｏｔａｌ However, it is determined whether or not it is greater than the threshold (step S106). Note that it is also possible that there is no traffic volume that has not been added. If there is no traffic volume that has not been added, the information analysis unit 222 may execute the process in step S108.

[0076] The information analysis unit 222 calculates the traffic volume sum value T. ｔｏｔａｌIf it is determined that the traffic volume is greater than the threshold (step S106-YES), or if there is no traffic volume that has not been added, the information analysis unit 222 determines the destination distributed station 15. Specifically, the information analysis unit 222 may determine the destination distributed station 15 from among the distributed stations 15 that have each traffic volume added up to before the processing in step S108 (for example, before the threshold is exceeded, or before there is no more traffic volume that has not been added), the distributed station 15 with the largest traffic volume.

[0077] For example, if each distributed station 15, whose traffic volume has been added up to the time of step S108, is distributed station 15-1 to 15-2, the information analysis unit 222 may decide that the distributed station 15 with the largest traffic volume among distributed stations 15-1 to 15-2 is the destination distributed station 15 for aggregation. Note that the method for determining the destination distributed station 15 is not limited to the above method, and other methods may be used (for example, determining the distributed station 15 with the second largest traffic volume as the destination distributed station 15). Here, let's assume that distributed station 15-2 has been determined as the destination.

[0078] Furthermore, the information analysis unit 222 determines which distributed stations 15 will be put into sleep mode (step S108). For example, the information analysis unit 222 determines that the distributed stations 15 other than the distributed station 15 that became the aggregation destination will be put into sleep mode from among the distributed stations 15 with the respective traffic amounts added up to the time before the processing in step S108 is executed. In the above example, the distributed stations 15 with the respective traffic amounts added up to the time before the processing in step S108 are distributed stations 15-1 to 15-2, and the distributed station 15 that became the aggregation destination is distributed station 15-2. Therefore, the information analysis unit 222 determines that distributed station 15-1 will be put into sleep mode. Distributed station 15-1, which has been determined to be put into sleep mode, is the source distributed station, and distributed station 15-2, which has been determined to be the aggregation destination, is the destination distributed station.

[0079] Subsequently, the information analysis unit 222 determines the optical path control section based on the determined source distributed station (e.g., distributed station 15-1) and destination distributed station (e.g., distributed station 15-2) (step S109). For example, the information analysis unit 222 determines the section connecting the transfer device 13 to each of the distributed stations 15-1 to 15-2 as the optical path control section.

[0080] In the example shown in Figure 2, the section connecting the transfer device 13 and the distributed station 15-1 consists of the first optical transceiver 131-1, the second optical transceiver 132-1, the optical transfer device 14-1, and the distributed station 15-1. Also in the example shown in Figure 2, the section connecting the transfer device 13 and the distributed station 15-2 consists of the first optical transceiver 131-2, the second optical transceiver 132-2, the optical transfer device 14-2, and the distributed station 15-2.

[0081] The information analysis unit 222 then identifies either the optical transceiver or optical transfer device 14 of the transfer device 13 that will no longer be used after the optical path is switched in the determined optical path control section. In other words, the information analysis unit 222 identifies either the optical transceiver or optical transfer device 14 of the first optical transceiver 131, the second optical transceiver 132, and the optical transfer device 14 of the transfer device 13 that will no longer be used after the optical path is switched.

[0082] In the above example, all the traffic aggregated by distributed station 15-1 will be aggregated at distributed station 15-2. In this case, the optical path will switch from the route of the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-1 of the transfer device 13, the optical transfer device 14-1 and distributed station 15-1 to the route of the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the optical transfer device 14-2 and distributed station 15-2.

[0083] Therefore, the optical transfer device 14-1 and the second optical transceiver 132-1 of the transfer device 13 will not be used. Accordingly, the information analysis unit 222 decides that the optical transfer device 14-1 and the second optical transceiver 132-1 of the transfer device 13 will also be put into sleep mode (step S110).

[0084] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep instruction. The information analysis unit 222 includes in the optical path control instruction information, for example, information indicating the source distributed station (e.g., distributed station 15-1), information indicating the destination distributed station (e.g., distributed station 15-2), and information indicating the radio station 12 to which the destination distributed station will be connected. Furthermore, the information analysis unit 222 includes in the sleep instruction information indicating, for example, the devices to be put into sleep mode (e.g., distributed station 15-1, optical transfer device 14-1, and the second optical transceiver 132-1 of the transfer device 13).

[0085] The optical path control unit 231 identifies the source distributed station and the destination distributed station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines distributed station 15-2 as the destination distributed station and distributed station 15-1 as the source distributed station. The optical path control unit 231 transmits optical path control information, including information indicating the determined source and destination distributed stations, to the transfer device 13 and the optical transfer device 14 (step S111).

[0086] As a result, the transfer device 13 and the optical transfer device 14 switch the optical path from one directed to distributed station 15-1 to one directed to distributed station 15-2. For example, the transfer device 13 connects the first optical transceiver 131-1 and the second optical transceiver 132-2 so that the uplink signal transmitted from radio station 12-1 is directed to distributed station 15-2. The optical transfer device 14-2 forms an optical path to transfer the uplink signal transmitted from radio station 12-1 to distributed station 15-2. The optical transfer device 14-1 identifies that the source distributed station is distributed station 15-1 based on the optical path control information. As a result, the optical transfer device 14-1 does not need to generate an optical path with the connected distributed station 15-1, and can therefore simply stop generating the optical path. At this point, the optical path control unit 231 may transmit optical path control instructions to the determined source distributed station and the radio station 12 connected to the source distributed station.

[0087] The sleep control unit 232 identifies the devices to be put into sleep mode based on the sleep instructions included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the distributed station 15-1, the optical transfer device 14-1, and the second optical transceiver 132-1 of the transfer device 13 as devices to be put into sleep mode. The sleep control unit 232 sends sleep permission notifications to the identified distributed station 15-1, the optical transfer device 14-1, and the transfer device 13 (step S112).

[0088] As a result, distributed station 15-1 enters sleep mode. Furthermore, optical transmission device 14-1 enters sleep mode. Furthermore, transmission device 13 enters sleep mode the second optical transceiver 132-1, which is identified by the information indicating the optical transceiver to be put into sleep mode included in the sleep permission notice.

[0089] In Figure 3, a configuration is shown in which sleep control is performed after optical path switching control is performed, but optical path switching control may also be performed after sleep control. Furthermore, in Figure 3, a configuration is shown in which the sleep control unit 232 puts the second optical transceiver 132, optical transfer device 14, and distributed station 15, which are equipped in the transfer device 13, into sleep mode, but the sleep control unit 232 may put both the distributed station 15 to be put into sleep mode and the radio station 12 connected to the distributed station 15 to be put into sleep mode via the transfer device 13 and the optical transfer device 14, or it may put only the radio station 12 into sleep mode.

[0090] [Sleep Wake-Up Process] Figure 4 is a flowchart showing an example of the sleep wake-up process performed by the management control device 20 in the first embodiment. Here, we will explain using the example of two distributed stations 15 (for example, distributed stations 15-1 to 15-2) and using traffic information as the cooperation information. For further simplification of the explanation, in the configuration shown in Figure 2, we will assume that radio stations 12-1 and 12-2 are connected to distributed station 15-1 via the transfer device 13 and the optical transfer device 14-1. We will also assume that distributed station 15-2, the optical transfer device 14-2, and the second optical transceiver 132-2 provided in the transfer device 13 are in a sleep state.

[0091] The information analysis unit 222 acquires the latest cooperation information for each distributed station 15 stored in the information storage unit 221 (step S201). In the management control device 20, cooperation information is collected at predetermined intervals or at arbitrary timings until the process shown in Figure 4 is executed. Therefore, the information storage unit 221 stores cooperation information for each distributed station 15 at predetermined intervals or at arbitrary timings. Thus, when the process shown in Figure 4 is started, the information analysis unit 222 acquires the latest cooperation information for each distributed station 15 at the start of the process shown in Figure 4.

[0092] The information analysis unit 222 calculates the traffic volume for each of the distributed stations 15-1 to 15-2 based on the latest acquired cooperation information for each distributed station 15 (step S202). The information analysis unit 222 compares the traffic volume for each of the distributed stations 15-1 to 15-2 with a threshold. The threshold used here may be the same as or different from the threshold used in Figure 3.

[0093] The information analysis unit 222 determines whether or not there are any distributed stations 15 whose traffic volume exceeds a threshold (step S203). If the information analysis unit 222 determines that there are no distributed stations 15 whose traffic volume exceeds a threshold (step S203-NO), the management control device 20 terminates the process shown in Figure 4.

[0094] On the other hand, if the information analysis unit 222 determines that there is a distributed station 15 whose traffic volume exceeds a threshold (step S203-YES), the information analysis unit 222 determines which distributed station 15 is to be woken from sleep mode (step S204). Here, let's assume that the distributed station 15 whose traffic volume exceeds the threshold is distributed station 15-1. The information analysis unit 222 identifies the other distributed station 15 with the highest traffic volume among the distributed stations 15 that are in sleep mode. Two identification methods are given below.

[0095] (Identification Method 1) Assuming that terminal 11 will reconnect to the original distributed station 15, the information analysis unit 222 first calculates the traffic volume of terminal 11 and then calculates the traffic volume of the sleeping distributed station 15. Then, the information analysis unit 222 identifies the distributed station 15 with the highest traffic volume among the calculated traffic volumes as the other distributed station 15 with the highest traffic volume among the traffic volumes aggregated to distributed station 15-1.

[0096] (Identification Method 2) First, the information analysis unit 222 predicts which distributed station 15 will be connected to after waking from sleep, based on the location of the terminal 11. Next, the information analysis unit 222 calculates the traffic volume of the sleeping distributed station 15 based on the prediction result. Then, the information analysis unit 222 identifies the distributed station 15 with the highest traffic volume among the calculated traffic volumes as the other distributed station 15 with the highest traffic volume among the traffic volumes aggregated to distributed station 15-1.

[0097] Assume that distributed station 15-2 is identified as the other distributed station 15 with the highest traffic volume by one of the identification methods described above. The information analysis unit 222 determines that the identified distributed station 15-2 is the distributed station 15 to be woken from sleep mode. Distributed station 15-1, whose traffic volume exceeds the threshold, is the source distributed station, and distributed station 15-2, which has been determined to be woken from sleep mode, is the destination distributed station.

[0098] Subsequently, the information analysis unit 222 determines the optical path control section based on the determined source distributed station (e.g., distributed station 15-1) and destination distributed station (e.g., distributed station 15-2) (step S205). For example, the information analysis unit 222 determines the section connecting the transfer device 13 to each of the distributed stations 15-1 to 15-2 as the optical path control section. Then, the information analysis unit 222 identifies one of the sleep-state first optical transceiver 131, sleep-state second optical transceiver 132, or sleep-state optical transfer device 14 that will be used after the optical path switching in the determined optical path control section.

[0099] In the above example, a portion of the traffic aggregated by distributed station 15-1 (for example, traffic transmitted from radio station 12-2) will be distributed to distributed station 15-2. In this way, the optical paths that need to be newly generated when disabling distributed station 15-2 are the paths between radio station 12-2, the first optical transceiver 131-2 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the optical transfer device 14-2, and distributed station 15-2.

[0100] Therefore, the sleep-state optical transfer device 14-2 and the sleep-state second optical transceiver 132-2 provided by the transfer device 13 will be used. Accordingly, the information analysis unit 222 decides that the sleep-state optical transfer device 14-2 and the sleep-state second optical transceiver 132-2 provided by the transfer device 13 will also be subject to being woken from sleep (step S206). In this way, the information analysis unit 222 decides that not only the sleep-state distributed station 15, but also any of the sleep-state optical transceivers provided by the transfer device 13 and the sleep-state optical transfer device 14 will also be subject to being woken from sleep.

[0101] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep wake-up instruction. The information analysis unit 222 includes, for example, information indicating the destination distributed station (e.g., distributed station 15-2) and information indicating the radio station 12 to which the destination distributed station will connect, in the optical path control instruction. Here, let's assume that the radio station 12 to which the destination distributed station will connect is radio station 12-2. Furthermore, the information analysis unit 222 includes, for example, information indicating the devices to be woken from sleep mode (e.g., distributed station 15-2, optical transfer device 14-2, and the second optical transceiver 132-2 of transfer device 13) in the sleep wake-up instruction.

[0102] The optical path control unit 231 identifies the target distributed station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines distributed station 15-2 as the target distributed station. The optical path control unit 231 transmits optical path control information, which includes information indicating the determined target distributed station and information indicating the radio station 12 (for example, radio station 12-2) to which the target distributed station will be connected, to the transfer device 13 and the optical transfer device 14 (step S207).

[0103] As a result, the transfer device 13 and the optical transfer device 14 switch the optical path from radio station 12-2 to distributed station 15-1 so that it goes from radio station 12-2 to distributed station 15-2. For example, the transfer device 13 switches the connection between the first optical transceiver 131-2 and the second optical transceiver 132-2 so that the uplink signal transmitted from radio station 12-2 goes to distributed station 15-2. The optical transfer device 14-2 forms an optical path to transfer the uplink signal transmitted from radio station 12-2 to distributed station 15-2. At this point, the optical path control unit 231 may transmit optical path control instructions to the determined destination distributed station and the radio station 12 connected to the destination distributed station.

[0104] The sleep control unit 232 identifies the devices to be woken from sleep based on the sleep wake-up instructions included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the distributed station 15-2, the optical transfer device 14-2, and the second optical transceiver 132-2 of the transfer device 13 as devices to be woken from sleep. The sleep control unit 232 transmits sleep wake-up instructions to the identified distributed station 15-2, the optical transfer device 14-2, and the transfer device 13 (step S208).

[0105] As a result, the distributed station 15-2 wakes up from sleep mode. Furthermore, the optical transfer device 14-2 wakes up from sleep mode. Furthermore, the transfer device 13 wakes up the sleep mode of the second optical transceiver 132-2, which is identified by the information indicating the optical transceiver to be woken up in the sleep wake-up instruction. As a result, the distributed station 15-2, the optical transceiver in the transfer device 13, and the optical transfer device 44 can be woken up from sleep mode.

[0106] In Figure 4, the sleep control unit 232 is shown to release the sleep state of the second optical transceiver 132, optical transfer device 14, and distributed station 15, which are all part of the transfer device 13. However, the sleep control unit 232 may release the sleep state of both the distributed station 15 that is to be released from sleep and the radio station 12 that is connected to the distributed station 15 via the transfer device 13 and the optical transfer device 14, or it may release the sleep state of the radio station 12.

[0107] According to the mobile network system 100 configured as described above, the management control device 20 includes a collection unit 21 that acquires cooperation information from a plurality of distributed stations 15, and an analysis unit 22 that determines which distributed stations 15 to put into sleep mode from among the plurality of distributed stations 15 based on the cooperation information, and, based on the determined distributed stations 15, causes at least one of the optical transceiver or optical transfer device 14 provided in the transfer device 13 to execute sleep control for the distributed stations 15 to be put into sleep mode.

[0108] This allows not only the distributed station 15 but also at least one of the optical transceivers or optical transmission devices 14 in the transmission device 13 to be put into sleep mode. As a result, it becomes possible to improve the power saving effect of the entire system compared to conventional methods.

[0109] Furthermore, in the mobile NW system 100, the analysis unit 22 determines which optical transceivers in the optical transfer device 14 or transfer device 13 are subject to sleep control, in accordance with the switching of the communication path (optical path) that occurs when the distributed station 15 to be put to sleep is put to sleep. Specifically, the analysis unit 22 determines which optical transceivers in the optical transfer device 14 or transfer device 13 will become unused in accordance with the switching of the communication path as targets for sleep control. If the optical transceivers in the optical transfer device 14 or transfer device 13 become unused in accordance with the switching of the communication path, they will consume power unnecessarily even though they are not being used if they remain running. Therefore, by having the analysis unit 22 determine which optical transceivers in the optical transfer device 14 or transfer device 13 will become unused in accordance with the switching of the communication path as targets for sleep control, it becomes possible to put them to sleep without affecting communication and to save power.

[0110] (Modification 1 in the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the transfer device may be configured to perform optical path control processing and sleep control processing. Figure 5 is a diagram showing an example of the configuration of the mobile NW system 100a in Modification 1 of the First Embodiment. The mobile NW system 100a comprises a radio station 12, a transfer device 13a, an optical transfer device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20a.

[0111] The example shown in Figure 5 illustrates a case where the mobile network system 100a comprises two radio stations 12-1 to 12-2, one transmission device 13a, two optical transmission devices 14-1 to 14-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13a, optical transmission devices 14, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system 100a is not particularly limited.

[0112] In Figure 5, the transfer device 13a and the optical transfer device 14 are arranged in the order of forward direction from the radio station 12 towards the server 18, but the arrangement of the transfer device 13a and the optical transfer device 14 is not limited to this. For example, they may be arranged in the order of transfer device 13a, optical transfer device 14, and transfer device 13a, or in the order of optical transfer device 14 and transfer device 13a, or only optical transfer device 14 may be arranged, or multiple optical transfer devices 14 may be arranged in a series (for example, in the order of optical transfer device 14-1, optical transfer device 14-2, ...).

[0113] As shown in Figure 5, the transfer device 13a includes a control unit 23, while the management control device 20a does not include a control unit 23. Although not shown in Figure 5, the transfer device 13a also includes first optical transceivers 131-1 to 131-2 and second optical transceivers 132-1 to 132-2, similar to the transfer device 13 shown in Figure 2.

[0114] The information analysis unit 222 of the management control device 20a notifies the transfer device 13a of the control information. The information analysis unit 222 may only notify the transfer device 13a of the control information when performing optical path control processing and sleep control processing. The control unit 23 of the transfer device 13a performs optical path control processing and sleep control processing based on the control information notified from the management control device 20a.

[0115] The control unit 23 of the transfer device 13a includes an optical path control unit 231 and a sleep control unit 232. The optical path control unit 231 performs the same processing as the optical path control unit 231 described above. The sleep control unit 232 performs the same processing as the sleep control unit 232 described above. For example, the sleep control unit 232 identifies the device to be put into sleep based on the sleep instruction included in the control information notified from the information analysis unit 222 of the management control device 20a. The device to be put into sleep identified by the sleep control unit 232 may include the first optical transceiver 131 or the second optical transceiver 132 equipped in the device itself. Therefore, the sleep control unit 232 sends a sleep permission notification to the identified distributed station 15 and the optical transfer device 14, and puts the first optical transceiver 131 or the second optical transceiver 132 to sleep into sleep mode.

[0116] (Modification 2 of the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical transfer device may be configured to perform optical path control processing and sleep control processing. Figure 6 is a diagram showing an example of the configuration of the mobile NW system 100b in Modification 2 of the First Embodiment. The mobile NW system 100b comprises a radio station 12, a transfer device 13, an optical transfer device 14b, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20b.

[0117] The example shown in Figure 6 illustrates a case where the mobile network system 100b comprises two radio stations 12-1 to 12-2, one transmission device 13, two optical transmission devices 14b-1 to 14b-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13, optical transmission devices 14b, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system 100b is not particularly limited.

[0118] In Figure 6, the transfer device 13 and optical transfer device 14b are arranged in the order of transfer device 13 and optical transfer device 14b from the radio station 12 towards the server 18 (upstream direction), but the arrangement of transfer device 13 and optical transfer device 14b is not limited to this. For example, they may be arranged in the order of transfer device 13, optical transfer device 14b, and transfer device 13 from the radio station 12 towards the server 18 (upstream direction), or in the order of optical transfer device 14b and transfer device 13, or only optical transfer device 14b may be arranged, or multiple optical transfer devices 14b may be arranged in a series (for example, in the order of optical transfer device 14b-1, optical transfer device 14b-2, ...).

[0119] As shown in Figure 6, the optical transmission device 14b is equipped with a control unit 23, while the management control device 20b is not equipped with a control unit 23. The information analysis unit 222 of the management control device 20b notifies each optical transmission device 14b of control information. The information analysis unit 222 may notify the optical transmission device 14b of control information only when performing optical path control processing and sleep control processing. The control unit 23 of the optical transmission device 14b performs optical path control processing and sleep control processing based on the control information notified from the management control device 20b.

[0120] The control unit 23 of the optical transmission device 14b comprises an optical path control unit 231 and a sleep control unit 232. The optical path control unit 231 performs the same processing as the optical path control unit 231 described above. The sleep control unit 232 performs the same processing as the sleep control unit 232 described above. For example, the sleep control unit 232 identifies the device to be put into sleep based on the sleep instruction included in the control information notified from the information analysis unit 222 of the management control device 20b. The device to be put into sleep identified by the sleep control unit 232 may include the device itself. In this case, the sleep control unit 232 sends a sleep permission notification to the identified distributed station 15 and the transmission device 13, and puts the device itself, which is to be put into sleep, into sleep mode.

[0121] Here, distributed station 15-1 is connected to optical transmission device 14b-1, and distributed station 15-2 is connected to optical transmission device 14b-2. Therefore, the sleep control unit 232 of the control unit 23 of optical transmission device 14b-1 sends a sleep permission notification to distributed station 15-1 if the identified distributed station 15 is distributed station 15-1. On the other hand, the sleep control unit 232 of the control unit 23 of optical transmission device 14b-1 does not send a sleep permission notification to distributed station 15-2 if the identified distributed station 15 is distributed station 15-2. Similarly, the sleep control unit 232 of the control unit 23 of optical transmission device 14b-2 does not send a sleep permission notification to distributed station 15-1 if the identified distributed station 15 is distributed station 15-1. On the other hand, the sleep control unit 232 of the control unit 23 of optical transmission device 14b-2 sends a sleep permission notification to distributed station 15-2 if the identified distributed station 15 is distributed station 15-2. Thus, the optical transmission device 14b may send a sleep permission notification to the distributed station 15 when it is connected to its own device.

[0122] Furthermore, although Figure 6 shows a configuration in which each of the two optical transmission devices 14b is equipped with a control unit 23, at least one of the optical transmission devices 14b may be equipped with a control unit 23. In this configuration, the optical transmission device 14b equipped with the control unit 23 may perform optical path control processing and sleep control processing.

[0123] (Modification 3 of the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the transfer device may be configured to perform sleep control processing and the optical transfer device may perform optical path control processing. Figure 7 is a diagram showing an example of the configuration of the mobile NW system 100c in Modification 3 of the First Embodiment. The mobile NW system 100c comprises a radio station 12, a transfer device 13c, an optical transfer device 14c, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20c.

[0124] The example shown in Figure 7 illustrates a case where the mobile network system 100c comprises two radio stations 12-1 to 12-2, one transmission device 13c, two optical transmission devices 14c-1 to 14c-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13c, optical transmission devices 14c, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system 100c is not particularly limited.

[0125] In Figure 7, the transfer device 13c and optical transfer device 14c are arranged in the order of transfer device 13c and optical transfer device 14c from the radio station 12 towards the server 18 (upstream direction), but the arrangement of the transfer device 13c and optical transfer device 14c is not limited to this. For example, they may be arranged in the order of transfer device 13c, optical transfer device 14c, and transfer device 13c from the radio station 12 towards the server 18 (upstream direction), or in the order of optical transfer device 14c and transfer device 13c, or only optical transfer device 14c may be arranged, or multiple optical transfer devices 14c may be arranged in a series (for example, in the order of optical transfer device 14c-1, optical transfer device 14c-2, ...).

[0126] As shown in Figure 7, the transfer device 13c includes a control unit 133, the optical transfer device 14c includes a control unit 141, and the management control device 20c does not include a control unit 23. Although not shown in Figure 7, the transfer device 13c also includes first optical transceivers 131-1 to 131-2 and second optical transceivers 132-1 to 132-2, similar to the transfer device 13 shown in Figure 2.

[0127] The information analysis unit 222 of the management control device 20c notifies the transfer device 13c and the optical transfer device 14c of control information. The information analysis unit 222 may notify the transfer device 13c and the optical transfer device 14c of control information only when performing optical path control processing and sleep control processing. The control unit 133 of the transfer device 13c performs sleep control processing based on the control information notified from the management control device 20c. The control unit 141 of the optical transfer device 14c performs optical path control processing based on the control information notified from the management control device 20c.

[0128] The control unit 141 of the optical transfer device 14c includes an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 described above. The control unit 133 of the transfer device 13c includes a sleep control unit 232. The sleep control unit 232 performs the same processing as the sleep control unit 232 described above. For example, the sleep control unit 232 identifies the device to be put into sleep based on the sleep instruction included in the control information notified from the information analysis unit 222 of the management control device 20c. The device to be put into sleep identified by the sleep control unit 232 may include the first optical transceiver 131 or the second optical transceiver 132 of its own device. Therefore, the sleep control unit 232 sends a sleep permission notification to the identified distributed station 15 and the optical transfer device 14c, and puts the first optical transceiver 131 or the second optical transceiver 132 to sleep into sleep mode.

[0129] (Modification 4 of the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the transfer device to perform optical path control processing. Figure 8 is a diagram showing an example of the configuration of the mobile NW system 100d in Modification 4 of the First Embodiment. The mobile NW system 100d comprises a radio station 12, a transfer device 13d, an optical transfer device 14, a distributed station 15, an aggregate station 16, a core device 17, a server 18, and a management control device 20d.

[0130] The example shown in Figure 8 illustrates a case where the mobile network system 100d comprises two radio stations 12-1 to 12-2, one transmission device 13d, two optical transmission devices 14-1 to 14-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13d, optical transmission devices 14, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system 100d is not particularly limited.

[0131] In Figure 8, the transfer device 13d and the optical transfer device 14 are arranged in the order of forward direction from the radio station 12 towards the server 18, but the arrangement of the transfer device 13d and the optical transfer device 14 is not limited to this. For example, they may be arranged in the order of transfer device 13d, optical transfer device 14, and transfer device 13d from the radio station 12 towards the server 18, or in the order of optical transfer device 14 and transfer device 13d, or only optical transfer device 14 may be arranged, or multiple optical transfer devices 14 may be arranged in a series (for example, in the order of optical transfer device 14-1, optical transfer device 14-2, ...).

[0132] As shown in Figure 8, the transfer device 13d includes a control unit 133d. Although not shown in Figure 8, the transfer device 13d also includes first optical transceivers 131-1 to 131-2 and second optical transceivers 132-1 to 132-2, similar to the transfer device 13 shown in Figure 2. The control unit 133d of the transfer device 13d includes an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 described above.

[0133] The management control device 20d comprises a collection unit 21, an analysis unit 22, and a control unit 23d. The control unit 23d includes a sleep control unit 232. The information analysis unit 222 of the management control device 20d notifies the transfer device 13d of control information including information indicating the source distributed station and information indicating the destination distributed station, and notifies the control unit 23d of control information including information indicating the device to be subjected to sleep control. The information analysis unit 222 may notify control information only when performing optical path control and sleep control. The sleep control unit 232 performs sleep control processing based on the control information notified by the information analysis unit 222.

[0134] (Modification 5 of the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the optical transfer device may perform optical path control processing. Figure 9 is a diagram showing an example of the configuration of the mobile NW system 100e in Modification 5 of the First Embodiment. The mobile NW system 100e comprises a radio station 12, a transfer device 13, an optical transfer device 14e, a distributed station 15, an aggregate station 16, a core device 17, a server 18, and a management control device 20e.

[0135] The example shown in Figure 9 illustrates a case where the mobile network system 100e comprises two radio stations 12-1 to 12-2, one transmission device 13, two optical transmission devices 14e-1 to 14e-2, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13, optical transmission devices 14e, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system 100e is not particularly limited.

[0136] In Figure 9, the transfer device 13 and optical transfer device 14e are arranged in the order of transfer device 13 and optical transfer device 14e from the radio station 12 towards the server 18 (upstream direction), but the arrangement of the transfer device 13 and optical transfer device 14e is not limited to this. For example, they may be arranged in the order of transfer device 13, optical transfer device 14e, and transfer device 13 from the radio station 12 towards the server 18 (upstream direction), or in the order of optical transfer device 14e and transfer device 13, or only optical transfer device 14e may be arranged, or multiple optical transfer devices 14e may be arranged in a series (for example, in the order of optical transfer device 14e-1, optical transfer device 14e-2, ...).

[0137] As shown in Figure 9, the optical transfer device 14e includes a control unit 141e. The control unit 141e of the optical transfer device 14e includes an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 described above.

[0138] The management control device 20e comprises a collection unit 21, an analysis unit 22, and a control unit 23e. The control unit 23e includes a sleep control unit 232. The information analysis unit 222 of the management control device 20e notifies the optical transmission device 14e of control information including information indicating the source distributed station and information indicating the destination distributed station, and notifies the control unit 23e of control information including information indicating the device to be subjected to sleep control. The information analysis unit 222 may notify control information only when performing optical path control and sleep control. The sleep control unit 232 performs sleep control processing based on the control information notified by the information analysis unit 222.

[0139] (Modification 6 of the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. Figure 10 shows an example of the configuration of a mobile NW system 100f in Modification 6 of the First Embodiment. The mobile NW system 100f includes a radio station 12, a transfer device 13, an optical transfer device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, an optical transmission management control device 65, and a wireless transmission management control device 70. As shown in Figure 10, in the mobile NW system 100f, the optical transmission management control device 65 and the wireless transmission management control device 70 are provided instead of the management control device 20.

[0140] The optical transmission management control device 65 controls the optical transmission section. The optical transmission management control device 65 includes a collection unit 21, an analysis unit 22, and a control unit 66. The collection unit 21 and the analysis unit 22 perform the same processing as the collection unit 21 and the analysis unit 22 of the management control device 20 described above. The control unit 66 includes an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 of the management control device 20 described above.

[0141] The wireless transmission management control device 70 controls the wireless transmission section. The wireless transmission management control device 70 includes a control unit 71. The control unit 71 includes a sleep control unit 232. The sleep control unit 232 performs the same processing as the sleep control unit 232 included in the management control device 20 described above.

[0142] The information analysis unit 222 of the optical transmission management control device 65 transmits control information, including information indicating the device to be controlled for sleep mode, to the wireless transmission management control device 70. Based on the control information transmitted from the optical transmission management control device 65, the wireless transmission management control device 70 causes the device to be controlled for sleep mode to either enter sleep mode or exit sleep mode.

[0143] This configuration allows multiple devices to perform different processes, such as switching optical paths and controlling sleep mode. This reduces the amount of processing required on a single device.

[0144] (Modification 7 in the First Embodiment) In the configuration shown in Figure 2, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. Figure 11 is a diagram showing an example configuration of a mobile NW system 100g in Modification 7 of the First Embodiment. The mobile NW system 100g includes a radio station 12, a transfer device 13, an optical transfer device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, an optical transmission management control device 65, and a wireless transmission management control device 70. As shown in Figure 11, in the mobile NW system 100g, the optical transmission management control device 65 and the wireless transmission management control device 70 are provided instead of the management control device 20.

[0145] The optical transmission management control device 65 shown in Figure 11 controls the optical transmission section. The optical transmission management control device 65 shown in Figure 11 includes a control unit 66. The control unit 66 includes an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 included in the management control device 20 described above.

[0146] The wireless transmission management control device 70 shown in Figure 11 controls the wireless transmission section. The wireless transmission management control device 70 shown in Figure 9 includes a data collection unit 21, an analysis unit 22, and a control unit 71. The data collection unit 21 and the analysis unit 22 perform the same processing as the data collection unit 21 and the analysis unit 22 of the management control device 20 described above. The control unit 71 includes a sleep control unit 232. The sleep control unit 232 performs the same processing as the sleep control unit 232 of the management control device 20 described above.

[0147] The information analysis unit 222 of the wireless transmission management control device 70 transmits control information to the optical transmission management control device 65, which includes information indicating the source distributed station and information indicating the destination distributed station. The optical transmission management control device 65 switches the optical path based on the control information transmitted from the wireless transmission management control device 70.

[0148] This configuration allows multiple devices to perform different processes, such as switching optical paths and controlling sleep mode. This reduces the amount of processing required on a single device.

[0149] (Modification 8 in the First Embodiment) The mobile NW system 100c shown in Figure 10 may be configured as shown in Figure 12. Figure 12 is a diagram showing an example configuration of the mobile NW system 100h in Modification 8 of the First Embodiment. The mobile NW system 100h includes a radio station 12, a transmission device 13, an optical transmission device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75. As shown in Figure 12, the mobile NW system 100h is further provided with an orchestrator 75 in addition to the mobile NW system 100f.

[0150] The orchestrator 75 is a higher-level device that controls the optical transmission management control device 65 and the wireless transmission management control device 70, and is positioned above the optical transmission management control device 65 and the wireless transmission management control device 70. The orchestrator 75 transfers signals between the optical transmission management control device 65 and the wireless transmission management control device 70. The orchestrator 75 includes a signal transfer unit 751. The signal transfer unit 751 receives control information sent from the optical transmission management control device 65 to the wireless transmission management control device 70. The signal transfer unit 751 transfers the received control information to the wireless transmission management control device 70.

[0151] The optical transmission management control device 65 performs the same processing as the optical transmission management control device 65 shown in Figure 10, except that it transmits control information destined for the wireless transmission management control device 70 to the orchestrator 75. The wireless transmission management control device 70 performs the same processing as the wireless transmission management control device 70 shown in Figure 10, except that it receives control information from the orchestrator 75.

[0152] (Modification 9 in the First Embodiment) The mobile NW system 100g shown in Figure 11 may be configured as shown in Figure 13. Figure 13 is a diagram showing an example configuration of the mobile NW system 100i in Modification 9 of the First Embodiment. The mobile NW system 100i includes a radio station 12, a transmission device 13, an optical transmission device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75. As shown in Figure 13, the mobile NW system 100i is further provided with an orchestrator 75 in addition to the mobile NW system 100g.

[0153] The orchestrator 75 is a higher-level device that controls the optical transmission management control device 65 and the wireless transmission management control device 70, and is positioned above the optical transmission management control device 65 and the wireless transmission management control device 70. The orchestrator 75 transfers signals between the optical transmission management control device 65 and the wireless transmission management control device 70. The orchestrator 75 includes a signal transfer unit 751. The signal transfer unit 751 receives control information sent from the wireless transmission management control device 70 to the optical transmission management control device 65. The signal transfer unit 751 transfers the received control information to the optical transmission management control device 65.

[0154] The optical transmission management control device 65 performs the same processing as the optical transmission management control device 65 shown in Figure 11, except that it receives control information from the orchestrator 75. The wireless transmission management control device 70 performs the same processing as the wireless transmission management control device 70 shown in Figure 11, except that it transmits control information intended for the optical transmission management control device 65 to the orchestrator 75.

[0155] (Modification 10 in the First Embodiment) The mobile NW system 100 may be configured as shown in Figure 14. Figure 14 is a diagram showing an example configuration of the mobile NW system 100j in modification 10 of the first embodiment. The mobile NW system 100j includes a radio station 12, a transfer device 13, an optical transfer device 14, a distributed station 15, an aggregation station 16, a core device 17, a server 18, an optical transmission management control device 65, and a wireless transmission management control device 70. As shown in Figure 14, the mobile NW system 100j is provided with an optical transmission management control device 65 and a wireless transmission management control device 70 instead of a management control device 20. The mobile NW system 100j is configured such that the optical transmission management control device 65 and the wireless transmission management control device 70 each receive cooperation information from each distributed station 15.

[0156] The optical transmission management control device 65 shown in Figure 14 comprises a collection unit 67, an analysis unit 68, and a control unit 66. The collection unit 67 comprises an acquisition unit 671. The acquisition unit 671 performs the same processing as the acquisition unit 211 of the management control device 20 described above. The analysis unit 68 comprises an information storage unit 681 and an information analysis unit 682. The information storage unit 681 and the information analysis unit 682 perform the same processing as the information storage unit 221 and the information analysis unit 222 of the management control device 20 described above. The control unit 66 comprises an optical path control unit 231. The optical path control unit 231 performs the same processing as the optical path control unit 231 of the management control device 20 described above.

[0157] The wireless transmission management control device 70 includes a collection unit 72, an analysis unit 73, and a control unit 71. The collection unit 72 includes an acquisition unit 721. The acquisition unit 721 performs the same processing as the acquisition unit 211 provided in the management control device 20 described above. The analysis unit 73 includes an information storage unit 731 and an information analysis unit 732. The information storage unit 731 and the information analysis unit 732 perform the same processing as the information storage unit 221 and the information analysis unit 222 provided in the management control device 20 described above. The control unit 71 includes a sleep control unit 232. The sleep control unit 232 performs the same processing as the sleep control unit 232 provided in the management control device 20 described above.

[0158] The timing at which the optical transmission management control device 65 performs optical path control processing and the timing at which the wireless transmission management control device 70 performs sleep control processing may be determined by each device. The mobile NW system 100j may include an orchestrator 75 that controls the optical transmission management control device 65 and the wireless transmission management control device 70, and the orchestrator 75 may synchronize the timing at which the optical transmission management control device 65 performs optical path control processing with the timing at which the wireless transmission management control device 70 performs sleep control processing.

[0159] (Modification 11 in the first embodiment) The cooperation information may include, for example, information on the number of terminals 11 that can be accommodated by each distributed station 15 (hereinafter referred to as "number of accommodated terminals"). The cooperation information may also include, for example, information on the processing load of the distributed station 15 (hereinafter referred to as "processing load information"). The processing load information may include, for example, information on the memory usage rate of the distributed station 15 or information on the CPU (Central Processing Unit) usage rate. The cooperation information may also include information on the communication quality of the terminals 11 connected to each distributed station 15 (hereinafter referred to as "communication quality information"). The communication quality information may include, for example, MCS (Modulation and Coding Scheme), RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), SINR (Signal-to-Noise Ratio), packet delay, location information, etc.

[0160] If the linked information includes information about the number of connected terminals, the information analysis unit 222 may use the information about the number of connected terminals to select the devices to be controlled for sleep (for example, devices to be controlled for sleep or devices to be disabled for sleep). In this configuration, the information analysis unit 222 can select the devices to be controlled for sleep (for example, the distributed station 15, the first optical transceiver 131 and second optical transceiver 132 of the transfer device 13, or the optical transfer device 14) in the same way as when using traffic information.

[0161] First, the information analysis unit 222 sorts each distributed station 15 in descending order of the number of connected terminals identified by the information regarding the number of connected terminals. Then, the information analysis unit 222 adds up the number of connected terminals in ascending order to the distributed station 15 with the fewest connected terminals. The information analysis unit 222 compares the summed total with a threshold and continues adding up the number of connected terminals in ascending order until it exceeds the threshold or until there are no more connected terminals that have not been added. Based on the number of connected terminals added up until it exceeds the threshold or until there are no more connected terminals that have not been added, the information analysis unit 222 selects a target for sleep from among the multiple distributed stations 15 related to the summed number of connected terminals. Next, the information analysis unit 222 determines the destination distributed station 15 for aggregation from among the multiple distributed stations 15 related to the summed number of connected terminals. For example, the information analysis unit 222 determines the destination distributed station 15 to be aggregated as the distributed station 15 that has the most connected terminals among the distributed stations 15 that have been aggregated within the range that does not exceed the threshold. Subsequently, the information analysis unit 222 determines, from among the multiple distributed stations 15 related to the total number of connected terminals, to be put into sleep mode, the distributed stations 15 other than the aggregation destination. Furthermore, the information analysis unit 222 determines, to be put into sleep mode, one of the first optical transceiver 131, the second optical transceiver 132, or the optical transfer device 14, which are equipped in the transfer device 13 that will not be used after the optical path switching.

[0162] If the linked information includes processing load information or communication quality information, the information analysis unit 222 may select sleep control targets (e.g., sleep targets or sleep wake targets) using the processing load information or communication quality information in addition to the traffic information. For example, when selecting sleep control targets using communication quality information in addition to traffic information, the information analysis unit 222 determines to perform sleep control if the conditions based on the traffic information and the conditions based on the communication quality information are met. The conditions based on the communication quality information may be, for example, conditions based on whether the route after sleep is feasible (e.g., whether quality degradation occurs). In this case, even if the distributed stations 15 that are sleep targets and optical path control targets are determined by the information analysis unit 222 based on the conditions based on the traffic information, it is possible that quality may degrade after the route is switched. Therefore, even if the distributed stations 15 that are sleep targets and optical path control targets are determined by the conditions based on the traffic information, the information analysis unit 222 may choose not to perform sleep if quality degrades in the route after optical path control.

[0163] (Second Embodiment) In the first embodiment, a configuration was shown in which each optical transmission device is connected to a different distributed station. In the second embodiment, a configuration will be described in which one optical transmission device receives multiple optical signals transmitted from a transmission device and transmits each of the received multiple optical signals to a distributed station.

[0164] (Outline of the Second Embodiment) Figure 15 is a diagram illustrating the overall configuration and processing overview of the mobile network system in the second embodiment. First, the overall configuration of the mobile network system in the second embodiment will be described. The mobile network system in the second embodiment is an example of a communication system. The mobile network system in the second embodiment is, for example, a fifth-generation mobile communication system (hereinafter referred to as "5G"). The mobile network system in the second embodiment comprises a radio station 12, a transmission device 13, an optical transmission device 14k, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20.

[0165] The following connections are made between the transfer device 13 and the optical transfer device 14k, between the optical transfer device 14k and the distributed station 15, between the distributed station 15 and the aggregation station 16, between the aggregation station 16 and the core device 17, and between the core device 17 and the server 18, using optical fibers to transmit optical signals. The following connections are made between the transfer device 13 and the management control device 20, between the optical transfer device 14k and the management control device 20, and between the distributed station 15 and the management control device 20, using either control lines (e.g., electric wires) or optical fibers to transmit control signals.

[0166] The example shown in Figure 15 illustrates a mobile network system comprising two radio stations 12-1 to 12-2, one transmission device 13, one optical transmission device 14k, and two distributed stations 15-1 to 15-2. The number of radio stations 12, transmission devices 13, optical transmission devices 14k, distributed stations 15, aggregation stations 16, core devices 17, and servers 18 in the mobile network system is not particularly limited.

[0167] In Figure 15, the transfer device 13 and optical transfer device 14k are arranged in the order of transfer device 13 and optical transfer device 14k from the radio station 12 towards the server 18 (upstream direction), but the arrangement of the transfer device 13 and optical transfer device 14k is not limited to this. For example, they may be arranged in the order of transfer device 13, optical transfer device 14k, and transfer device 13 from the radio station 12 towards the server 18 (upstream direction), or in the order of optical transfer device 14k and transfer device 13, or only optical transfer device 14k may be arranged, or multiple optical transfer devices 14k may be arranged in a series (for example, in the order of optical transfer device 14k-1, optical transfer device 14k-2, ...).

[0168] The mobile network system in the second embodiment differs from the mobile network system in the first embodiment in the configuration of the optical transmission device 14k and the processing of the management control device 20. Therefore, the optical transmission device 14k and the management control device 20 will be described below.

[0169] The optical transmission device 14k is provided between the transmission device 13 and the distribution station 15. The optical transmission device 14k is, for example, an optical switch or ROADM. The optical transmission device 14k transmits optical signals transmitted from each transmission device 13 to the destination distribution station 15, or transmits optical signals transmitted from the distribution station 15 to the destination transmission device 13.

[0170] The optical transfer device 14k controls the optical path according to the optical path control information transmitted from the management control device 20. For example, the optical path control performed by the optical transfer device 14k includes switching optical paths and forming new optical paths. By controlling the optical paths, the optical transfer device 14k controls the connection between the multiple transfer devices 13 and the multiple distributed stations 15. For example, when the optical transfer device 14k receives optical path control information transmitted from the management control device 20, it performs a switch so that an optical path is connected between the transfer device 13 and the distributed station 15, which are the destinations of the optical path switch.

[0171] The optical transmission device 14k includes multiple optical transceivers (not shown in Figure 15) for transmitting and receiving optical signals between multiple transmission devices 13 and multiple distributed stations 15. Each optical transceiver has, for example, the function of receiving an optical signal transmitted from the transmission device 13 and forwarding the received optical signal to the destination distributed station 15, and the function of receiving an optical signal transmitted from the distributed station 15 and forwarding the received optical signal to the transmission device 13.

[0172] Furthermore, the optical transmission device 14k transitions the optical transceiver specified by the sleep instruction to a sleep state in accordance with the sleep instruction transmitted from the management control device 20. The optical transceiver specified by the sleep instruction is, for example, an optical transceiver that will no longer be used due to the switching of an optical path. An optical transceiver that will no longer be used is an optical transceiver that does not need to be made usable and is the optical transceiver that will be put into sleep mode.

[0173] Furthermore, if the optical transceiver identified by the sleep instruction transmitted from the management control device 20 is an optical transceiver that communicates with the distributed station 15-1, the optical transceiver 14k will enter a sleep state among the multiple optical transceivers that communicate with the distributed station 15-1. In this way, unlike the first embodiment, the optical transceiver 14k does not enter a sleep state itself, but rather enters a sleep state among the multiple optical transceivers that will no longer be used due to the switching of the optical path.

[0174] Furthermore, the optical transmission device 14k releases the sleep state of the optical transceiver specified by the sleep release instruction, in accordance with the sleep release instruction transmitted from the management control device 20. The optical transceiver specified by the sleep release instruction is, for example, an optical transceiver used by switching optical paths. The optical transceiver used is an optical transceiver that needs to be made available for use and is the optical transceiver to be released from sleep.

[0175] For example, if the optical transceiver identified by the sleep-release instruction transmitted from the management control device 20 is an optical transceiver that communicates with the distributed station 15-1, the optical transceiver 14k will be released from the sleep state among the multiple optical transceivers that communicate with the distributed station 15-1. In this way, the optical transceiver 14k transitions the optical transceiver used by switching the optical path from the sleep state to the active state among the multiple optical transceivers. The optical transceiver 14k is one embodiment of other devices and relay devices.

[0176] The collaborative information in the second embodiment includes, for example, traffic information from each distributed station 15. The traffic information is the same as in the first embodiment.

[0177] The management control device 20 differs from the first embodiment in its processing of the optical transfer device 14k, but its other operations are the same as the first embodiment. Specifically, during optical path control processing, the management control device 20 determines whether there are any optical transceivers that will not be used for signal transfer after the optical path is switched. In the first embodiment, the management control device 20 determined whether there were any optical transceivers in the transfer device 13 or optical transfer device 14k that would not be used for signal transfer after the optical path was switched. In contrast, in the second embodiment, the management control device 20 determines whether there are any optical transceivers in the transfer device 13 or optical transfer device 14k that will not be used for signal transfer after the optical path is switched.

[0178] The control unit 20 determines that any optical transceivers that are not used for signal transmission after the optical path has been switched are subject to sleep control. The control unit 20 then sends a sleep instruction to the transfer device 13 or the optical transfer device 14k that has the unused optical transceivers. The control unit 20 does not determine that any optical transceivers are subject to sleep control if there are no optical transceivers that are not used for signal transmission after the optical path has been switched.

[0179] Furthermore, during optical path control processing, the management control device 20 determines whether or not there is an optical transceiver in a sleep state that will be used for signal transfer after the optical path is switched. In the first embodiment, the management control device 20 determined whether or not there was an optical transceiver in a sleep state provided by the transfer device 13 used for signal transfer after the optical path was switched, or an optical transfer device 14k in a sleep state. In contrast, in the second embodiment, the management control device 20 determines whether or not there is an optical transceiver in a sleep state provided by the transfer device 13 used for signal transfer after the optical path is switched, or an optical transceiver in a sleep state provided by the optical transfer device 14k. Thus, in the second embodiment, the management control device 20 determines whether or not there is an optical transceiver in a sleep state that will be used for signal transfer after the optical path is switched.

[0180] If there are optical transceivers in a sleep state in the transfer device 13 or optical transfer device 14k that are used for signal transfer after switching the optical path, the management control device 20 determines that the optical transceivers in a sleep state in the transfer device 13 or optical transfer device 14k that are used for signal transfer are targets for sleep control. The management control device 20 then sends a sleep release instruction to the transfer device 13 or optical transfer device 14k that have the optical transceivers in a sleep state that are used for signal transfer. If there are no optical transceivers in a sleep state in the transfer device 13 or optical transfer device 14k that are used for signal transfer after switching the optical path, the management control device 20 does not determine that the optical transceivers in a sleep state in the transfer device 13 or optical transfer device 14k are targets for sleep control.

[0181] Next, an overview of the processing of the mobile network system in the second embodiment will be described. The upper part of Figure 15 shows the connection status of the mobile network system before optical path switching, and the lower part of Figure 15 shows the connection status of the mobile network system after optical path switching. In the upper part of Figure 15, it is assumed that radio station 12-1 is connected to distributed station 15-1, and radio station 12-2 is connected to distributed station 15-2.

[0182] The management control device 20 determines, based on the coordination information collected from each distributed station 15, that sleep control is possible if one distributed station 15 can accommodate the traffic of the other distributed stations 15. In other words, based on the coordination information collected from each distributed station 15, the management control device 20 performs optical path control processing and sleep control processing if one distributed station 15 can accommodate the traffic of the other distributed stations 15. In this way, by accommodating the traffic of the other distributed stations 15 to one distributed station 15, the other distributed stations 15 whose traffic has ceased can be put into sleep mode.

[0183] When the management control device 20 performs optical path control processing, it instructs the transfer device 13 and the optical transfer device 14k to switch optical paths. The management control device 20 determines the route after the optical path switch during the optical path control processing. Therefore, the management control device 20 can identify optical transceivers that will not be used after the optical path switch in the section between the radio station 12 and the distributed station 15.

[0184] For example, as shown in the lower diagram of Figure 15, the management control device 20 determines that distributed station 15-1 can be put into sleep mode if distributed station 15-2 can accommodate all of the traffic from distributed station 15-1. Then, in the optical path control processing, the management control device 20 transmits optical path control information to the transfer device 13 instructing it to switch the path from the transfer device 13 to distributed station 15-1 via the optical transfer device 14k to the path from the transfer device 13 to distributed station 15-2 via the optical transfer device 14k.

[0185] As a result, in the path after the optical path is switched, the optical transceiver connected to the distributed station 15-1 among the multiple optical transceivers provided by the optical transfer device 14k, and the optical transceiver of the transfer device 13 connected to the optical transceiver connected to the distributed station 15-1, will not be used. Therefore, the management control device 20 determines that in the path after the optical path is switched, the optical transceiver connected to the distributed station 15-1 among the multiple optical transceivers provided by the optical transfer device 14k, and the optical transceiver of the transfer device 13 connected to the optical transceiver connected to the distributed station 15-1, will not be used. The management control device 20 then determines that sleep control is also possible for the optical transceiver connected to the distributed station 15-1 among the multiple optical transceivers provided by the optical transfer device 14k, and the optical transceiver of the transfer device 13 connected to the optical transceiver connected to the distributed station 15-1.

[0186] The transfer device 13 switches the optical path between the radio station 12 and the optical transfer device 14k in accordance with the optical path switching instruction from the management control device 20. For example, the transfer device 13 switches the optical path of the optical transceiver connected to the radio station 12-1 so that it connects to the optical transceiver connected to the distributed station 15-2 among the multiple optical transceivers provided by the optical transfer device 14k. As a result, the transfer device 13 can transfer the uplink signal transmitted from the radio station 12-1 to the distributed station 15-2 via the optical transfer device 14k.

[0187] The optical transmission device 14k switches the optical path between the transmission device 13 and the distributed station 15 in accordance with the optical path switching instruction from the management control device 20. For example, the optical transmission device 14k switches the optical path so that it connects the optical transceiver connected to the radio station 12-1 among the multiple optical transceivers provided by the transmission device 13 to the optical transceiver connected to the distributed station 15-2 among the multiple optical transceivers provided by the device itself. As a result, the optical transmission device 14k can transmit the uplink signal transmitted from the transmission device 13 to the distributed station 15-2.

[0188] The transfer device 13 and the optical transfer device 14k notify the management control device 20 of the completion of the optical path switching after the optical path switching is complete. Since the connection destination of terminal 11 changes due to the optical path switching, the management control device 20 may instruct the distributed station 15, which is the target of the optical path switching, to change its connection.

[0189] When the management control device 20 receives notification of completion of optical path switching from a device subject to optical path switching (for example, the transfer device 13 or the optical transfer device 14k), it sends a sleep permission notification to devices that can transition to sleep mode. In the example shown in the lower part of Figure 15, the management control device 20 determines that the distributed station 15-1, the optical transceiver of the optical transfer device 14k connected to the distributed station 15-1, and the optical transceiver of the transfer device 13 connected to the optical transceiver of the optical transfer device 14k connected to the distributed station 15-1 are devices that can transition to sleep mode. Therefore, the management control device 20 sends a sleep permission notification to the transfer device 13, the optical transfer device 14k, and the distributed station 15-1.

[0190] In the second embodiment, the sleep permission notification transmitted by the management control device 20 to the transfer device 13 and the optical transfer device 14k includes information indicating the optical transceiver to be put into sleep mode. As a result, the device to be controlled for sleep mode transitions to sleep mode.

[0191] The lower diagram of Figure 15 shows an example in which radio stations 12-1 to 12-2 are connected to distributed station 15-2, and distributed station 15-1, the optical transceiver of the optical transfer device 14k connected to distributed station 15-1, and the optical transceiver of the transfer device 13 connected to the optical transceiver of the optical transfer device 14k connected to distributed station 15-1 are all in a sleep state. Based on the cooperation information collected from each distributed station 15, the management control device 20 causes devices that are capable of entering a sleep state to enter a sleep state by connecting terminals 11 connected to distributed stations 15 that are capable of entering a sleep state to other distributed stations 15.

[0192] (Details of the second embodiment) Figure 16 shows an example of the configuration of the mobile NW system 100k in the second embodiment. The mobile NW system 100k in the second embodiment includes a radio station 12, a transmission device 13, an optical transmission device 14k, a distributed station 15, an aggregation station 16, a core device 17, a server 18, and a management control device 20. The radio station 12, distributed station 15, aggregation station 16, core device 17, and server 18 were explained in Figure 15, so their explanation is omitted here.

[0193] The transfer device 13 comprises first optical transceivers 131-1 to 131-2 and second optical transceivers 132-1 to 132-2. In Figure 16, for the sake of simplicity, the transfer device 13 is shown to have a configuration comprising two first optical transceivers 131 and two second optical transceivers 132, but the number of first optical transceivers 131 and second optical transceivers 132 is not particularly limited.

[0194] The first optical transceiver 131 transmits and receives signals with the radio station 12. The first optical transceiver 131 forwards the uplink signal transmitted from the radio station 12 to the second optical transceiver 132, which is the forwarding destination. The first optical transceiver 131 also forwards the downlink signal transmitted from the second optical transceiver 132 to the destination radio station 12.

[0195] The second optical transceiver 132 transmits and receives signals with the optical transfer device 14k. The second optical transceiver 132 converts the uplink signal transmitted from the first optical transceiver 131 into an optical signal and transfers it to the destination optical transfer device 14k. The second optical transceiver 132 also converts the optical signal transmitted from the optical transfer device 14k into a downlink signal (electrical signal) and transfers it to the destination first optical transceiver 131.

[0196] The optical transmission device 14k includes a first optical transceiver 142 and a second optical transceiver 143. In Figure 16, for the sake of simplicity, the optical transmission device 14k is shown to have a configuration comprising two first optical transceivers 142-1 to 142-2 and two second optical transceivers 143-1 to 143-2, but the number of first optical transceivers 142 and second optical transceivers 143 is not particularly limited.

[0197] The first optical transceiver 142 transmits and receives signals with the second optical transceiver 132 provided in the transfer device 13. The first optical transceiver 142 transfers the optical signal transmitted from the second optical transceiver 132 to the second optical transceiver 143, which is the transfer destination. The first optical transceiver 142 also transfers the optical signal transmitted from the second optical transceiver 143 to the connected second optical transceiver 132.

[0198] The second optical transceiver 143 transmits and receives signals with the distributed station 15. The second optical transceiver 143 forwards the optical signal transferred from the first optical transceiver 142 to the connected distributed station 15. The second optical transceiver 143 also forwards the optical signal transmitted from the connected distributed station 15 to the first optical transceiver 142, which is the transfer destination.

[0199] In the transfer device 13 shown in Figure 16, the first optical transceiver 131-1 and the second optical transceiver 132-1 are connected, and the first optical transceiver 131-2 and the second optical transceiver 132-2 are connected. Based on optical path control information transmitted from the management control device 20, the transfer device 13 switches the connection between the first optical transceiver 131 and the second optical transceiver 132. For example, as shown in Figure 15, when switching the optical path to transfer the uplink signal transmitted from the radio station 12-1 to the distributed station 15-2 via the optical transfer device 14k, the transfer device 13 switches to connect the first optical transceiver 131-1 and the second optical transceiver 132-2. As a result, the uplink signal transmitted from the radio station 12-1 is transferred to the first optical transceiver 142-2 in the optical transfer device 14k via the first optical transceiver 131-1 and the second optical transceiver 132-2.

[0200] In the optical transmission device 14k shown in Figure 16, the first optical transceiver 142-1 and the second optical transceiver 143-1 are connected, and the first optical transceiver 142-2 and the second optical transceiver 143-2 are connected. Based on optical path control information transmitted from the management control device 20, the optical transmission device 14k switches the connection between the first optical transceiver 142 and the second optical transceiver 143. For example, as shown in Figure 15, when switching the optical path to transfer the uplink signal transmitted from the radio station 12-1 to the distributed station 15-2, the optical transmission device 14k forms an optical path between the first optical transceiver 142-1 and the second optical transceiver 143-1, and between the first optical transceiver 142-2 and the second optical transceiver 143-2. ​​This allows the optical signal input to the first optical transceiver 142-2 to be output from the second optical transceiver 143-2.

[0201] [Configuration of the Management Control Device 20] Next, the configuration of the management control device 20 in the second embodiment will be described. The management control device 20 includes a collection unit 21, an analysis unit 22, and a control unit 23. The management control device 20 in the second embodiment differs from the first embodiment in the process of determining the sleep control target. The differences from the first embodiment will be described below.

[0202] The information analysis unit 222 identifies the first optical transceiver 131 and second optical transceiver 132 in the transfer device 13, or the first optical transceiver 142 and second optical transceiver 143 in the optical transfer device 14k, which will no longer be used after the optical path is switched in the determined optical path control section. In this way, the information analysis unit 222 in the second embodiment identifies the optical transceiver in at least one of the transfer device 13 or the optical transfer device 14k that will no longer be used after the optical path is switched.

[0203] If there are any first optical transceivers 131, second optical transceivers 132 in the transfer device 13 or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k that will no longer be used after the optical path is switched, the information analysis unit 222 decides to put one of the first optical transceivers 131, second optical transceivers 132 in the transfer device 13 or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k that will no longer be used into sleep mode. If there are no first optical transceivers 131, second optical transceivers 132 in the transfer device 13 or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k that will no longer be used after the optical path is switched, the information analysis unit 222 does not perform any special processing.

[0204] Furthermore, the information analysis unit 222 identifies the first optical transceiver 131 and second optical transceiver 132 in the sleep-state transfer device 13 used after switching the optical path in the optical path control section, or the first optical transceiver 142 and second optical transceiver 143 in the optical transfer device 14k. In this way, the information analysis unit 222 in the second embodiment identifies the sleep-state optical transceiver used after switching the optical path in at least one of the transfer device 13 or the optical transfer device 14k.

[0205] If there are any first optical transceivers 131, second optical transceivers 132 in the sleep-state transfer device 13 to be used after the optical path switching, or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k, the information analysis unit 222 determines which of the first optical transceivers 131, second optical transceivers 132 in the sleep-state transfer device 13 to be used, or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k to be woken from sleep. If there are no first optical transceivers 131, second optical transceivers 132 in the sleep-state transfer device 13 to be used after the optical path switching, or first optical transceivers 142, second optical transceivers 143 in the optical transfer device 14k, the information analysis unit 222 does not perform any special processing.

[0206] The control unit 23 includes an optical path control unit 231 and a sleep control unit 232. The optical path control unit 231 determines the source distributed station and the destination distributed station based on the results of the analysis by the information analysis unit 222. For example, the optical path control unit 231 determines the source distributed station based on information indicating the source distributed station included in the control information notified by the information analysis unit 222. For example, the optical path control unit 231 determines the destination distributed station based on information indicating the destination distributed station included in the control information notified by the information analysis unit 222. The optical path control unit 231 holds information on the radio station 12 connected to the distributed station 15.

[0207] [Sleep Processing] Figure 17 is a flowchart showing an example of the sleep processing flow performed by the management control device 20 in the second embodiment. Here, we will explain using the example of two distributed stations 15 (for example, distributed stations 15-1 to 15-2) and using traffic information as the cooperation information. Furthermore, for the sake of simplicity, we will assume that the connection configuration of each device is as shown in Figure 16. In Figure 17, processes similar to those in Figure 3 are denoted by the same reference numerals as in Figure 3 and their explanations will be omitted.

[0208] After the processes from step S101 to step S108 are executed, in the process of step S109, the information analysis unit 222 determines the sections connecting the transfer device 13 and each of the distributed stations 15-1 to 15-2 as the optical path control sections.

[0209] In the example shown in Figure 16, the section connecting the transfer device 13 and the distributed station 15-1 consists of the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-1 of the transfer device 13, the first optical transceiver 142-1 of the optical transfer device 14k, the second optical transceiver 143-1 of the optical transfer device 14k, and the distributed station 15-1. Also in the example shown in Figure 16, the section connecting the transfer device 13 and the distributed station 15-2 consists of the first optical transceiver 131-2 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 of the optical transfer device 14k, the second optical transceiver 143-2 of the optical transfer device 14k, and the distributed station 15-2.

[0210] The information analysis unit 222 then identifies the optical transceivers that will no longer be used after the optical path is switched in the determined optical path control section. Specifically, the information analysis unit 222 identifies the optical transceivers that will no longer be used after the optical path is switched from among the first optical transceiver 131 and second optical transceiver 132 of the transfer device 13, and the first optical transceiver 142 and second optical transceiver 143 of the optical transfer device 14k.

[0211] In the above example, all traffic accommodated at distributed station 15-1 will be aggregated at distributed station 15-2. In this case, the optical path will be switched from the route of the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-1 of the transfer device 13, the first optical transceiver 142-1 of the optical transfer device 14k, the second optical transceiver 143-1 of the optical transfer device 14k and distributed station 15-1 to the route of the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 of the optical transfer device 14k, the second optical transceiver 143-2 of the optical transfer device 14k and distributed station 15-2.

[0212] Therefore, the second optical transceiver 132-1 of the transfer device 13 and the first optical transceiver 142-1 and second optical transceiver 143-1 of the optical transfer device 14k will not be used. Accordingly, the information analysis unit 222 also decides that the second optical transceiver 132-1 of the transfer device 13 and the first optical transceiver 142-1 and second optical transceiver 143-1 of the optical transfer device 14k will also be put into sleep mode (step S301).

[0213] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep instruction. The information analysis unit 222 includes in the optical path control instruction information, for example, information indicating the source distributed station (e.g., distributed station 15-1), information indicating the destination distributed station (e.g., distributed station 15-2), and information indicating the radio station 12 to which the destination distributed station will be connected. Furthermore, the information analysis unit 222 includes in the sleep instruction information indicating, for example, the devices to be put into sleep mode (e.g., distributed station 15-1, the first optical transceiver 142-1 and second optical transceiver 143-1 of the optical transfer device 14k, and the second optical transceiver 132-1 of the transfer device 13).

[0214] The optical path control unit 231 identifies the source distributed station and the destination distributed station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines distributed station 15-2 as the destination distributed station and distributed station 15-1 as the source distributed station. The optical path control unit 231 transmits optical path control information, which includes information indicating the determined source and destination distributed stations, to the transfer device 13 and the optical transfer device 14k (step S302).

[0215] As a result, the transfer device 13 and the optical transfer device 14k switch the optical path from one directed towards distributed station 15-1 to one directed towards distributed station 15-2. For example, the transfer device 13 connects the first optical transceiver 131-1 and the second optical transceiver 132-2 so that the uplink signal transmitted from radio station 12-1 is directed towards distributed station 15-2. The optical transfer device 14k connects the first optical transceiver 142-1 and the second optical transceiver 143-2 so that the uplink signal transmitted from radio station 12-1 is directed towards distributed station 15-2. At this point, the optical path control unit 231 may transmit optical path control instructions to the determined source distributed station and the radio station 12 connected to the source distributed station.

[0216] The sleep control unit 232 identifies the devices to be put into sleep mode based on the sleep instructions included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the distributed station 15-1, the first optical transceiver 142-1 and the second optical transceiver 143-1 of the optical transfer device 14k, and the second optical transceiver 132-1 of the transfer device 13 as devices to be put into sleep mode. The sleep control unit 232 sends sleep permission notifications to the identified distributed station 15-1, the optical transfer device 14k, and the transfer device 13 (step S303).

[0217] As a result, distributed station 15-1 enters sleep mode. Furthermore, optical transmission device 14k enters sleep mode for the first optical transceiver 142-1 and the second optical transceiver 143-1, which are identified by the information indicating the optical transceivers to be put into sleep mode included in the sleep permission notice. Furthermore, transmission device 13 enters sleep mode for the second optical transceiver 132-1, which is identified by the information indicating the optical transceivers to be put into sleep mode included in the sleep permission notice.

[0218] In Figure 17, a configuration is shown in which sleep control is performed after optical path switching control is performed, but optical path switching control may also be performed after sleep control. Furthermore, in Figure 17, a configuration is shown in which the sleep control unit 232 puts the second optical transceiver 132 of the transfer device 13, the first optical transceiver 142, the second optical transceiver 143 and the distributed station 15 of the optical transfer device 14k into sleep mode, but the sleep control unit 232 may put both the distributed station 15 to be put into sleep mode and the radio station 12 connected to the distributed station 15 to be put into sleep mode via the transfer device 13 and the optical transfer device 14k, or it may put only the radio station 12 into sleep mode.

[0219] [Sleep Wake-Up Process] Figure 18 is a flowchart showing an example of the sleep wake-up process performed by the management control device 20 in the second embodiment. Here, we will explain using the example of two distributed stations 15 (for example, distributed stations 15-1 to 15-2) and using traffic information as the cooperation information. For further simplification of the explanation, in the configuration shown in Figure 16, we will assume that radio stations 12-1 and 12-2 are connected to distributed station 15-1 via the transfer device 13 and the optical transfer device 14k. We will also assume that the second optical transceiver 132-2 provided in distributed station 15-2 and the transfer device 13, and the first optical transceiver 142-2 and second optical transceiver 143-2 provided in the optical transfer device 14k are in a sleep state. In Figure 18, processes similar to those in Figure 4 are denoted by the same reference numerals as in Figure 4 and their explanation will be omitted.

[0220] After the processes from step S201 to step S204 are executed, in the process of step S205, the information analysis unit 222 determines the section connecting the transfer device 13 and each of the distributed stations 15-1 to 15-2 as the optical path control section. The information analysis unit 222 then identifies either the first optical transceiver 131 or the second optical transceiver 132 of the sleep-state transfer device 13 that will be used after the optical path switching in the determined optical path control section, or the first optical transceiver 142 or the second optical transceiver 143 of the sleep-state optical transfer device 14k.

[0221] In the above example, a portion of the traffic aggregated by distributed station 15-1 (for example, traffic transmitted from radio station 12-2) will be distributed to distributed station 15-2. In this way, the optical paths that need to be newly generated when disabling distributed station 15-2 are the paths between radio station 12-2, the first optical transceiver 131-2 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 of the optical transfer device 14k, the second optical transceiver 143-2 of the optical transfer device 14k, and distributed station 15-2.

[0222] Therefore, the first optical transceiver 142-2 and the second optical transceiver 143-2, both in sleep mode, provided by the optical transfer device 14k, and the second optical transceiver 132-2, both in sleep mode, provided by the transfer device 13, will be used. Accordingly, the information analysis unit 222 decides that the first optical transceiver 142-2 and the second optical transceiver 143-2, both in sleep mode, provided by the optical transfer device 14k, and the second optical transceiver 132-2, both in sleep mode, provided by the transfer device 13, will also be subject to being woken from sleep mode (step S401). In this way, the information analysis unit 222 decides that not only the distributed station 15 in sleep mode, but also any optical transceiver in sleep mode provided by the transfer device 13 or the optical transfer device 14k will also be subject to being woken from sleep mode.

[0223] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep wake-up instruction. The information analysis unit 222 includes, for example, information indicating the destination distributed station (e.g., distributed station 15-2) and information indicating the radio station 12 to which the destination distributed station will connect, in the optical path control instruction. Here, let's assume that the radio station 12 to which the destination distributed station will connect is radio station 12-2. Furthermore, the information analysis unit 222 includes, for example, information indicating the devices to be woken from sleep mode (e.g., distributed station 15-2, the first optical transceiver 142-2 and second optical transceiver 143-2 of the optical transfer device 14k, and the second optical transceiver 132-2 of the transfer device 13), in the sleep instruction.

[0224] The optical path control unit 231 identifies the target distributed station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines distributed station 15-2 as the target distributed station. The optical path control unit 231 transmits optical path control information, which includes information indicating the determined target distributed station and information indicating the radio station 12 (for example, radio station 12-2) to which the target distributed station will be connected, to the transfer device 13 and the optical transfer device 14k (step S402).

[0225] As a result, the transfer device 13 and the optical transfer device 14k switch the optical path from radio station 12-2 to distributed station 15-1 so that it goes from radio station 12-2 to distributed station 15-2. For example, the transfer device 13 connects the first optical transceiver 131-2 and the second optical transceiver 132-2 so that the uplink signal transmitted from radio station 12-2 goes to distributed station 15-2. The optical transfer device 14k connects the first optical transceiver 142-2 and the second optical transceiver 143-2 so that the uplink signal transmitted from radio station 12-2 goes to distributed station 15-2. At this point, the optical path control unit 231 may transmit optical path control instructions to the determined destination distributed station and the radio station 12 connected to the destination distributed station.

[0226] The sleep control unit 232 identifies the devices to be woken from sleep based on the sleep wake-up instructions included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the distributed station 15-2, the first optical transceiver 142-2 and the second optical transceiver 143-2 of the optical transfer device 14k, and the second optical transceiver 132-2 of the transfer device 13 as devices to be woken from sleep. The sleep control unit 232 transmits sleep wake-up instructions to the identified distributed station 15-2, the optical transfer device 14k, and the transfer device 13 (step S403).

[0227] As a result, the distributed station 15-2 wakes up from sleep mode. Furthermore, the optical transfer device 14k wakes up the sleep mode of the first optical transceiver 142-2 and the second optical transceiver 143-2, which are identified by the information indicating the optical transceiver to be woken up in the sleep wake-up instruction. Furthermore, the transfer device 13 wakes up the sleep mode of the second optical transceiver 132-2, which is identified by the information indicating the optical transceiver to be woken up in the sleep wake-up instruction. As a result, the distributed station 15-2, the optical transceiver in the transfer device 13, and the optical transceiver in the optical transfer device 44k can be woken up from sleep mode.

[0228] In Figure 18, the sleep control unit 232 is shown to release the sleep state of the optical transceiver in the transfer device 13, the optical transceiver in the optical transfer device 14k, and the distributed station 15. However, the sleep control unit 232 may release the sleep state of both the distributed station 15 to be released from sleep and the radio station 12 connected to the distributed station 15 via the transfer device 13 and the optical transfer device 14k, or it may release the sleep state of the radio station 12.

[0229] In the mobile network system 100k configured as described above, the management control device 20 includes a collection unit 21 that acquires cooperation information from a plurality of distributed stations 15, an analysis unit 22 that determines which distributed stations 15 to put into sleep mode from among the plurality of distributed stations 15 based on the cooperation information, and, based on the determined distributed stations 15, causes at least one of the optical transceivers provided in the transfer device 13 or the optical transceiver provided in the optical transfer device 14k to execute sleep control on the distributed stations 15 to be put into sleep mode.

[0230] This allows not only the distributed station 15, but also at least one of the optical transceivers in the transfer device 13 or the optical transceiver in the optical transfer device 14k to be put into sleep mode. As a result, it becomes possible to improve the power saving effect of the entire system compared to conventional methods.

[0231] (Modification 1 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 is shown to perform optical path control processing and sleep control processing. In contrast, the transfer device may be configured to perform optical path control processing and sleep control processing. In this configuration, the mobile NW system 100k is equipped with a transfer device 13a shown in Figure 5 instead of the transfer device 13, and a management control device 20a shown in Figure 5 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 5.

[0232] (Modification 2 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical transfer device may be configured to perform optical path control processing and sleep control processing. In this configuration, the mobile NW system 100k is equipped with an optical transfer device 14b shown in Figure 6 instead of the optical transfer device 14k, and a management control device 20b shown in Figure 6 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 6.

[0233] (Modification 3 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the transfer device may be configured to perform sleep control processing and the optical transfer device may perform optical path control processing. In this configuration, the mobile NW system 100k is equipped with a transfer device 13c shown in Figure 7 instead of a transfer device 13, an optical transfer device 14c shown in Figure 7 instead of an optical transfer device 14k, and a management control device 20c shown in Figure 7 instead of a management control device 20. The sleep control processing can be the same as the processing described in Figure 16, and the other processing is the same as in Figure 7.

[0234] (Modification 4 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the transfer device to perform optical path control processing. In this configuration, the mobile NW system 100k is equipped with a transfer device 13d shown in Figure 8 instead of the transfer device 13, and a management control device 20d shown in Figure 8 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 8.

[0235] (Modification 5 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the optical transfer device to perform optical path control processing. In this configuration, the mobile NW system 100k is equipped with an optical transfer device 14e shown in Figure 9 instead of the optical transfer device 14k, and a management control device 20e shown in Figure 9 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 9.

[0236] (Modification 6 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. In this configuration, the mobile NW system 100k includes an optical transmission management control device 65 and a wireless transmission management control device 70 as shown in Figure 10 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 10.

[0237] (Modification 7 in the second embodiment) In the configuration shown in Figure 16, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. In this configuration, the mobile NW system 100k includes an optical transmission management control device 65 and a wireless transmission management control device 70 as shown in Figure 11 instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 11.

[0238] (Modification 8 in the second embodiment) The mobile NW system 100k may be configured as shown in Figure 12. In this configuration, the mobile NW system 100k includes an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75 as shown in Figure 12, instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 12.

[0239] (Modification 9 in the second embodiment) The mobile NW system 100k may be configured as shown in Figure 13. In this configuration, the mobile NW system 100k includes an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75 as shown in Figure 13, instead of the management control device 20. The sleep control processing can be performed as described in Figure 16, and the other processing is the same as in Figure 13.

[0240] (Modification 10 in the second embodiment) The mobile NW system 100k may be configured as shown in Figure 14. In this configuration, the mobile NW system 100k includes an optical transmission management control device 65 and a wireless transmission management control device 70 as shown in Figure 14, instead of the management control device 20. The sleep control process can be performed as described in Figure 16, and the other processes are the same as in Figure 14.

[0241] (Modification 11 in the second embodiment) The cooperation information may include, for example, information regarding the number of terminals that can be accommodated. The cooperation information may include, for example, processing load information. The cooperation information may include communication quality information.

[0242] If the linked information includes information about the number of connected terminals, the information analysis unit 222 may use the information about the number of connected terminals to select devices to be controlled for sleep (for example, devices to be controlled for sleep or devices to be disabled for sleep). In this configuration, the information analysis unit 222 can select devices to be controlled for sleep (for example, the distributed station 15, the first optical transceiver 131 and second optical transceiver 132 of the transfer device 13, or the first optical transceiver 142 and second optical transceiver 143 of the optical transfer device 14k) in the same way as when using traffic information.

[0243] First, the information analysis unit 222 sorts each distributed station 15 in descending order of the number of connected terminals identified by the information regarding the number of connected terminals. Then, the information analysis unit 222 adds up the number of connected terminals in ascending order to the distributed station 15 with the fewest connected terminals. The information analysis unit 222 compares the summed total with a threshold and continues adding up the number of connected terminals in ascending order until it exceeds the threshold or until there are no more connected terminals that have not been added. Based on the number of connected terminals added up until it exceeds the threshold or until there are no more connected terminals that have not been added, the information analysis unit 222 selects a target for sleep from among the multiple distributed stations 15 related to the summed number of connected terminals. Next, the information analysis unit 222 determines the destination distributed station 15 for aggregation from among the multiple distributed stations 15 related to the summed number of connected terminals. For example, the information analysis unit 222 determines the destination distributed station 15 to be aggregated as the distributed station 15 that has the most connected terminals among the distributed stations 15 that have been aggregated within the range that does not exceed the threshold. Subsequently, the information analysis unit 222 determines, from among the multiple distributed stations 15 related to the total number of connected terminals, to be put into sleep mode, except for the distribution station 15 that is the aggregation destination. Furthermore, the information analysis unit 222 determines, to be put into sleep mode, one of the first optical transceiver 131 or second optical transceiver 132 of the transfer device 13 that will not be used after the optical path switching, or the first optical transceiver 142 or second optical transceiver 143 of the optical transfer device 14k.

[0244] If the linked information includes processing load information or communication quality information, the information analysis unit 222 may select sleep control targets (e.g., sleep targets or sleep wake targets) using the processing load information or communication quality information in addition to the traffic information. For example, when selecting sleep control targets using communication quality information in addition to traffic information, the information analysis unit 222 determines to perform sleep control if the conditions based on the traffic information and the conditions based on the communication quality information are met. The conditions based on the communication quality information may be, for example, conditions based on whether the route after sleep is feasible (e.g., whether quality degradation occurs). In this case, even if the distributed stations 15 that are sleep targets and optical path control targets are determined by the information analysis unit 222 based on the conditions based on the traffic information, it is possible that quality may degrade after the route is switched. Therefore, even if the distributed stations 15 that are sleep targets and optical path control targets are determined by the conditions based on the traffic information, the information analysis unit 222 may choose not to perform sleep if quality degrades in the route after optical path control.

[0245] (Third Embodiment) In the third embodiment, a configuration comprising a base station in which a radio station, a distributed station, and an aggregated station are integrated will be described.

[0246] (Outline of the Third Embodiment) Figure 19 is a diagram illustrating the overall configuration and processing overview of the mobile network system in the third embodiment. First, the overall configuration of the mobile network system in the third embodiment will be described. The mobile network system in the third embodiment is an example of a communication system. The mobile network system in the third embodiment is, for example, 5G. The mobile network system in the third embodiment comprises a transmission device 13, an optical transmission device 14k, a core device 17, a server 18, a base station 19, and a management control device 20.

[0247] The transfer device 13 and the optical transfer device 14k, the optical transfer device 14k and the core device 17, and the core device 17 and the server 18 are connected by optical fibers that transmit optical signals. The base station 19 and the transfer device 13, the transfer device 13 and the management control device 20, the optical transfer device 14k and the management control device 20, and the base station 19 and the management control device 20 may be connected by control lines (e.g., electric wires) or optical fibers to transmit control signals.

[0248] The example shown in Figure 19 illustrates a mobile network system comprising two base stations 19-1 to 19-2, one transmission device 13, and one optical transmission device 14k. The number of transmission devices 13, optical transmission devices 14k, core device 17, server 18, and base stations 19 in the mobile network system is not particularly limited.

[0249] In Figure 19, the transfer device 13 and optical transfer device 14k are arranged in the order of transfer device 13 and optical transfer device 14k from the radio station 12 towards the server 18 (upstream direction), but the arrangement of the transfer device 13 and optical transfer device 14k is not limited to this. For example, they may be arranged in the order of transfer device 13, optical transfer device 14k, and transfer device 13 from the radio station 12 towards the server 18 (upstream direction), or in the order of optical transfer device 14k and transfer device 13, or only optical transfer device 14k may be arranged, or multiple optical transfer devices 14k may be arranged in a series (for example, in the order of optical transfer device 14k-1, optical transfer device 14k-2, ...).

[0250] The base station 19 is a device that integrates a radio station, a distributed station, and an aggregation station. The base station 19 is equipped with one or more antennas and performs wireless communication with one or more terminals 11 located within the communication area. For example, each base station 19 transmits uplink signals transmitted from one or more terminals 11 to the core device 17 via the transfer device 13 and the optical transfer device 14k. The base station 19 transmits downlink signals received via the transfer device 13 and the optical transfer device 14k to one or more terminals 11. The base station 19 transmits coordination information to the management control device 20. The coordination information in the third embodiment is information about each base station 19, for example, information indicating the communication status between each base station 19 and the terminal 11. The coordination information in the third embodiment includes, for example, traffic information of each base station 19. The traffic information is the same as in the first embodiment.

[0251] If the base station 19 is equipped with multiple antennas, the base station 19 may perform wireless communication with one or more terminals 11 by beamforming. The base station 19 enters a sleep state in accordance with a sleep instruction transmitted from the management control device 20. The base station 19 exits the sleep state in accordance with a sleep wake instruction transmitted from the management control device 20.

[0252] In the third embodiment, the transfer device 13 is provided between the base station 19 and the optical transfer device 14k. The transfer device 13 is, for example, a router or L2 switch that has the function of transferring optical signals. The transfer device 13 includes a plurality of optical transceivers (not shown in Figure 19). The transfer device 13 in the third embodiment performs the same processing as in the first embodiment, except that the base station 19 is connected instead of the radio station 12, and the optical transfer device 14k is connected instead of the optical transfer device 14.

[0253] In the third embodiment, the optical transfer device 14k is provided between the transfer device 13 and the core device 17. The optical transfer device 14k is, for example, an optical switch or ROADM. The optical transfer device 14k includes a plurality of optical transceivers (not shown in Figure 19). The optical transfer device 14k in the third embodiment performs the same processing as in the second embodiment, except that the core device 17 is connected instead of the distributed station 15.

[0254] In the third embodiment, the management control device 20 is a device that manages the entire mobile network system. The management control device 20 acquires cooperation information from each base station 19. When acquiring cooperation information from each base station 19, the management control device 20 uses a cooperation interface. Based on the acquired cooperation information, the management control device 20 determines whether or not optical path control and sleep control are necessary.

[0255] For example, the management control device 20 may determine that optical path control is necessary when it determines that sleep control is possible. The management control device 20 performs optical path control processing and sleep control processing when it determines that sleep control is necessary. The optical path control processing in the third embodiment is the process of causing the transfer device 13 and the optical transfer device 14k to switch optical paths or generate optical paths between the base station 19 and the optical transfer device 14k. The sleep control processing in the third embodiment is the process of causing the device to be subject to sleep control to perform sleep or to release the sleep state. In the third embodiment, the devices subject to sleep control are the multiple optical transceivers provided in the transfer device 13, the multiple optical transceivers provided in the optical transfer device 14k, and the base station 19.

[0256] Next, an overview of the processing of the mobile network system in the third embodiment will be described. The upper part of Figure 19 shows the connection state of the mobile network system before optical path switching, and the lower part of Figure 19 shows the connection state of the mobile network system after optical path switching. In the upper part of Figure 19, two terminals 11 are connected to base station 19-1, base station 19-1 is connected to core device 17 via transfer device 13 and optical transfer device 14k, and two terminals 11 are connected to base station 19-2, base station 19-2 is connected to core device 17 via transfer device 13 and optical transfer device 14k.

[0257] The management control device 20 determines, based on the coordination information collected from each base station 19, that sleep control is possible if one base station 19 can accommodate the traffic of the other base stations 19. In other words, the management control device 20 performs optical path control processing and sleep control processing if one base station 19 can accommodate the traffic of the other base stations 19 based on the coordination information collected from each base station 19. In this way, by accommodating the traffic of the other base stations 19 to one base station 19, the other base stations 19 whose traffic has ceased can be put into sleep mode.

[0258] When the management control device 20 performs optical path control processing, it instructs the transfer device 13 and the optical transfer device 14k to switch optical paths. The management control device 20 determines the route after the optical path switch during the optical path control processing. Therefore, the management control device 20 can identify the optical transceivers that will not be used after the optical path switch in the section between the base station 19 and the optical transfer device 14k. The optical transceivers that will not be used after the optical path switch are any of the optical transceivers provided by the transfer device 13 or any of the optical transceivers provided by the optical transfer device 14k.

[0259] For example, as shown in the lower diagram of Figure 19, the management control device 20 determines that base station 19-1 can be put into sleep mode if base station 19-2 can accommodate all of the traffic from base station 19-1. Then, in the optical path control processing, the management control device 20 transmits optical path control information to the transfer device 13 instructing it to switch the path from base station 19-1 to optical transfer device 14k to a path from base station 19-2 to optical transfer device 14k.

[0260] As a result, in the route after the optical path is switched, the optical transceiver connected to the base station 19-1 among the multiple optical transceivers of the transfer device 13, and some of the optical transceivers of the multiple optical transceivers of the optical transfer device 14k will not be used. Therefore, the management control device 20 determines that in the route after the optical path is switched, the optical transceiver connected to the base station 19-1 among the multiple optical transceivers of the transfer device 13, and some of the optical transceivers of the multiple optical transceivers of the optical transfer device 14k will not be used. The management control device 20 then determines that sleep control is also possible for the optical transceiver connected to the base station 19-1 among the multiple optical transceivers of the transfer device 13, and some of the optical transceivers of the multiple optical transceivers of the optical transfer device 14k.

[0261] The transfer device 13 switches the optical path between the base station 19 and the optical transfer device 14k in accordance with the optical path switching instruction from the management control device 20. The optical transfer device 14k switches the optical path between the transfer device 13 and the core device 17 in accordance with the optical path switching instruction from the management control device 20.

[0262] The transfer device 13 and the optical transfer device 14k notify the management control device 20 of the completion of the optical path switching after the optical path switching is complete. Since the connection destination of the terminal 11 changes due to the optical path switching, the management control device 20 may instruct the base station 19 that is subject to the optical path switching to change its connection.

[0263] When the management control device 20 receives notification of completion of optical path switching from the device to be switched (for example, the transfer device 13 or the optical transfer device 14k), it sends a sleep permission notification to the devices that can enter sleep mode. In the example shown in the lower part of Figure 19, the management control device 20 determines that the base station 19-1, the optical transceivers of the transfer device 13 connected to the base station 19-1, and some of the optical transceivers of the optical transfer device 14k are devices that can enter sleep mode. Therefore, the management control device 20 sends a sleep permission notification to the transfer device 13, the optical transfer device 14k, and the base station 19-1.

[0264] In the third embodiment, the sleep permission notification transmitted by the management control device 20 to the transfer device 13 and the optical transfer device 14k includes information indicating the optical transceiver to be put into sleep mode. As a result, the device to be controlled for sleep mode transitions to sleep mode.

[0265] The lower diagram of Figure 19 shows an example in which four terminals 11 are connected to base station 19-2, and base station 19-1, some optical transceivers of the transfer device 13 that will not be used after the optical path switchover, and some optical transceivers of the optical transfer device 14k have entered a sleep state. Based on the cooperation information collected from each base station 19, the management control device 20 moves the terminals 11 connected to a base station 19 that can enter a sleep state to another base station 19, thereby putting the devices that can enter a sleep state into a sleep state. Hereinafter, the base station 19 that is the source of the optical path switchover will be referred to as the source base station, and the base station 19 that is the destination of the optical path switchover will be referred to as the destination base station.

[0266] (Details of the Third Embodiment) Figure 20 shows an example of the configuration of the mobile network system 200 in the third embodiment. The mobile network system 200 in the third embodiment includes a transmission device 13, an optical transmission device 14k, a core device 17, a server 18, a base station 19, and a management control device 20. The core device 17, server 18, and base station 19 have been explained in Figure 19, so their explanation is omitted here.

[0267] The transfer device 13 comprises first optical transceivers 131-1 to 131-2 and second optical transceivers 132-1 to 132-2. In Figure 20, for the sake of simplicity, the transfer device 13 is shown to have a configuration comprising two first optical transceivers 131 and two second optical transceivers 132, but the number of first optical transceivers 131 and second optical transceivers 132 is not particularly limited.

[0268] The first optical transceiver 131 transmits and receives signals with the base station 19. The first optical transceiver 131 forwards the uplink signal transmitted from the base station 19 to the second optical transceiver 132, which is the forwarding destination. The first optical transceiver 131 also forwards the downlink signal transmitted from the second optical transceiver 132 to the base station 19, which is the destination.

[0269] The second optical transceiver 132 transmits and receives signals with the optical transfer device 14k. The second optical transceiver 132 converts the uplink signal transmitted from the first optical transceiver 131 into an optical signal and transfers it to the destination optical transfer device 14k. The second optical transceiver 132 also converts the optical signal transmitted from the optical transfer device 14k into a downlink signal (electrical signal) and transfers it to the destination first optical transceiver 131.

[0270] The optical transmission device 14k includes a first optical transceiver 142 and a second optical transceiver 143. In Figure 20, for the sake of simplicity, the optical transmission device 14k is shown to have a configuration comprising two first optical transceivers 142-1 to 142-2 and two second optical transceivers 143-1 to 143-2, but the number of first optical transceivers 142 and second optical transceivers 143 is not particularly limited.

[0271] The first optical transceiver 142 transmits and receives signals with the second optical transceiver 132 provided in the transfer device 13. The first optical transceiver 142 transfers the optical signal transmitted from the second optical transceiver 132 to the second optical transceiver 143, which is the transfer destination. The first optical transceiver 142 also transfers the optical signal transmitted from the second optical transceiver 143 to the connected second optical transceiver 132.

[0272] The second optical transceiver 143 transmits and receives signals with the core device 17. The second optical transceiver 143 forwards the optical signals transferred from the first optical transceiver 142 to the core device 17. The second optical transceiver 143 also forwards the optical signals transmitted from the core device 17 to the first optical transceiver 142, which is the transfer destination.

[0273] [Configuration of the Management Control Device 20] The management control device 20 comprises a collection unit 21, an analysis unit 22, and a control unit 23. The collection unit 21 comprises an acquisition unit 211. The acquisition unit 211 acquires various types of information. For example, the acquisition unit 211 collects cooperation information from base stations 19 at predetermined intervals or at arbitrary timings. The acquisition unit 211 collects traffic information from each base station 19 as cooperation information.

[0274] The analysis unit 22 comprises an information storage unit 221 and an information analysis unit 222. The information storage unit 221 records the cooperation information collected by the acquisition unit 211 in a predetermined storage device. The information analysis unit 222 analyzes the communication status between each base station 19 and the terminal 11 based on the cooperation information. Specifically, the information analysis unit 222 determines whether optical path control and sleep control are necessary based on the cooperation information.

[0275] For example, the information analysis unit 222 determines that it will perform optical path control processing and sleep control processing if all terminals 11 accommodated by one base station 19 can be accommodated by any of the base stations 19. In this case, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep instruction. The optical path control instruction in the third embodiment is an instruction to request switching of the optical path, and includes, for example, information indicating the source base station and information indicating the destination base station. The sleep instruction in the third embodiment is an instruction to send a sleep permission notification, and includes, for example, information indicating the device to be put into sleep mode. The method for determining the optical path control interval and the method for selecting the device to be put into sleep mode in the information analysis unit 222 is the same as in the second embodiment.

[0276] Furthermore, the information analysis unit 222 determines that if the traffic volume of a certain base station 19 exceeds a threshold, it will perform optical path control processing and sleep control processing. In this case, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep release instruction. The sleep release instruction in the third embodiment is an instruction to release the sleep state, and includes information indicating, for example, the base station 19 to be released from sleep, the optical transceiver provided in the optical transfer device 14k, and the optical transceiver provided in the transfer device 13. The method for selecting the target for sleep release in the information analysis unit 222 is the same as in the second embodiment.

[0277] The control unit 23 includes an optical path control unit 231 and a sleep control unit 232. The optical path control unit 231 determines the source base station and the destination base station based on the results of the analysis by the information analysis unit 222. For example, the optical path control unit 231 determines the source base station based on information indicating the source base station included in the control information notified by the information analysis unit 222. For example, the optical path control unit 231 determines the destination base station based on information indicating the destination base station included in the control information notified by the information analysis unit 222.

[0278] The optical path control unit 231 transmits optical path control information, including information indicating the determined switching destination base station, to the transfer device 13 and the optical transfer device 14k. This instructs the transfer device 13 and the optical transfer device 14k to switch the optical path.

[0279] Based on the results of the analysis by the information analysis unit 222, the sleep control unit 232 causes the device subject to sleep control to either enter sleep mode or exit sleep mode.

[0280] [Sleep Processing] Figure 21 is a flowchart showing an example of the sleep processing flow performed by the management control device 20 in the third embodiment. Here, we will explain using the example of two base stations 19 (for example, base stations 19-1 to 19-2) and using traffic information as the cooperation information. Furthermore, for the sake of simplicity, we will assume that the connection configuration of each device is as shown in Figure 20.

[0281] The information analysis unit 222 acquires the latest cooperation information for each base station 19 stored in the information storage unit 221 (step S501). In the management control device 20, cooperation information is collected at predetermined intervals or at arbitrary timings until the process shown in Figure 21 is executed. Therefore, the information storage unit 221 stores cooperation information for each base station 19 at predetermined intervals or at arbitrary timings. When the process shown in Figure 21 is started, the information analysis unit 222 acquires the latest cooperation information for each base station 19 at the start of the process shown in Figure 21.

[0282] The information analysis unit 222 calculates the traffic volume of each of the base stations 19-1 to 19-2 based on the latest cooperation information obtained for each base station 19. Then, the information analysis unit 222 rearranges the base stations 19-1 to 19-2 in ascending order of the calculated traffic volume (step S502).

[0283] The information analysis unit 222 determines the addition target A for the traffic volume (step S503). The addition target A in the third embodiment is, for example, the base station 19 with the least traffic volume. As an example, here, the base station 19 with the least traffic volume is set as the base station 19-1. Next, the information analysis unit 222 determines the addition target B for the traffic volume (step S404). The addition target B in the third embodiment is, for example, the base station 19 with the second least traffic volume. As an example, here, the base station 19 with the second least traffic volume is set as the base station 19-2. The information analysis unit 222 calculates the traffic volume addition value T ｔｏｔａｌ by adding the traffic volume of the addition target A and the traffic volume of the addition target B (step S505).

[0284] The information analysis unit 222 compares the calculated traffic volume addition value T ｔｏｔａｌ with a threshold value. Here, the threshold value is a value for control judgment and may be the same value for each base station 19 or different values for each base station 19. The threshold value may be calculated by the information analysis unit 222 based on the cooperation information and recorded in the information storage unit 221, or may be held by the information analysis unit 222 in advance for each base station 19. When the threshold value of each base station 19 is recorded in the information storage unit 221, the information analysis unit 222 may read and use the threshold value recorded in the information storage unit 221. The information analysis unit 222 compares the calculated traffic volume addition value T ｔｏｔａｌ with the threshold value of the base station 19 corresponding to the addition target A.

[0285] The information analysis unit 222 determines whether the traffic volume addition value T ｔｏｔａｌ is greater than the threshold value (step S506). When the information analysis unit 222 determines that the traffic volume addition value T ｔｏｔａｌHowever, if it is determined that the amount is not greater than the threshold (step S506-NO), the information analysis unit 222 adds the smallest traffic amount among the traffic amounts that have not been added, thereby creating a new traffic amount addition value T ｔｏｔａｌ Calculate (step S507).

[0286] Subsequently, the information analysis unit 222 executes the process in step S506 again. In this case, the information analysis unit 222 calculates the newly calculated traffic volume sum value T. ｔｏｔａｌ However, it is determined whether or not it is greater than the threshold (step S506). Note that there may be cases where there is no traffic volume that has not been added. If there is no traffic volume that has not been added, the information analysis unit 222 may execute the process in step S508.

[0287] The information analysis unit 222 calculates the traffic volume sum value T. ｔｏｔａｌ If it is determined that the traffic volume is greater than the threshold (step S506 - YES), or if there is no traffic volume that has not been added, the information analysis unit 222 determines the base station 19 to be aggregated. Specifically, the information analysis unit 222 may determine the base station 19 with the largest traffic volume from among the base stations 19 that have each traffic volume added up to before the processing in step S508 is executed (for example, before the threshold is exceeded, or before there is no more traffic volume that has not been added), as the base station 19 to be aggregated.

[0288] For example, if the base stations 19 with the summed traffic amounts before executing the process in step S508 are base stations 19-1 to 19-2, the information analysis unit 222 may decide that the base station 19 with the largest traffic amount among base stations 19-1 to 19-2 is the base station 19 to be aggregated. Note that the method for determining the base station 19 to be aggregated is not limited to the above method, and other methods may be used (for example, determining the base station 19 with the second largest traffic amount as the base station 19 to be aggregated). Here, let's assume that base station 19-2 is determined to be the aggregation destination.

[0289] Furthermore, the information analysis unit 222 determines which base stations 19 will be put into sleep mode (step S508). For example, the information analysis unit 222 determines which base stations 19 will be put into sleep mode from among the base stations 19 with the respective traffic amounts added up to the time before the processing in step S508, excluding the base station 19 that became the aggregation destination. In the above example, the base stations 19 with the respective traffic amounts added up to the time before the processing in step S508 are base stations 19-1 to 19-2, and the base station 19 that became the aggregation destination is base station 19-2. Therefore, the information analysis unit 222 determines base station 19-1 to be put into sleep mode. Base station 19-1, which has been determined to be put into sleep mode, is the source base station, and base station 19-2, which has been determined to be the aggregation destination, is the destination base station.

[0290] Subsequently, the information analysis unit 222 determines the optical path control section based on the determined source base station (e.g., base station 19-1) and destination base station (e.g., base station 19-2) (step S509). For example, the information analysis unit 222 determines the section connecting each of the base stations 19-1 to 19-2 to the optical transmission device 14k as the optical path control section.

[0291] In the example shown in Figure 20, the section connecting base station 19-1 and optical transmission device 14k consists of base station 19-1, the first optical transceiver 131-1 of transmission device 13, the second optical transceiver 132-1 of transmission device 13, the first optical transceiver 142-1 of optical transmission device 14k, and the second optical transceiver 143-1 of optical transmission device 14k. Also in the example shown in Figure 20, the section connecting base station 19-2 and optical transmission device 14k consists of base station 19-2, the first optical transceiver 131-2 of transmission device 13, the second optical transceiver 132-2 of transmission device 13, the first optical transceiver 142-2 of optical transmission device 14k, and the second optical transceiver 143-2 of optical transmission device 14k.

[0292] The information analysis unit 222 then identifies the optical transceivers that will no longer be used after the optical path is switched in the determined optical path control section. Specifically, the information analysis unit 222 identifies the optical transceivers that will no longer be used after the optical path is switched from among the first optical transceiver 131 and second optical transceiver 132 of the transfer device 13, and the first optical transceiver 142 and second optical transceiver 143 of the optical transfer device 14k.

[0293] In the above example, all traffic received by base station 19-1 will be aggregated at base station 19-2. In this case, the optical path will be switched from the route of base station 19-1, the first optical transceiver 131-1 of the transfer device 13, the second optical transceiver 132-1 of the transfer device 13, the first optical transceiver 142-1 of the optical transfer device 14k, the second optical transceiver 143-1 of the optical transfer device 14k and the core device 17 to the route of base station 19-2, the first optical transceiver 131-2 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 of the optical transfer device 14k, the second optical transceiver 143-2 of the optical transfer device 14k and the core device 17.

[0294] Therefore, the first optical transceiver 131-1 and the second optical transceiver 132-1 of the transfer device 13, and the first optical transceiver 142-1 and the second optical transceiver 143-1 of the optical transfer device 14k will not be used. Accordingly, the information analysis unit 222 also decides that the first optical transceiver 131-1 and the second optical transceiver 132-1 of the transfer device 13, and the first optical transceiver 142-1 and the second optical transceiver 143-1 of the optical transfer device 14k will also be put into sleep mode (step S510).

[0295] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep instruction. The information analysis unit 222 includes, for example, information indicating the source base station (e.g., base station 19-1) and information indicating the destination base station (e.g., base station 19-2) in the optical path control instruction. Furthermore, the information analysis unit 222 includes, for example, information indicating the devices to be put into sleep mode (e.g., base station 19-1, the first optical transceiver 131-1 and second optical transceiver 132-1 of the transfer device 13, and the first optical transceiver 142-1 and second optical transceiver 143-1 of the optical transfer device 14k) in the sleep instruction.

[0296] The optical path control unit 231 identifies the source base station and the destination base station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines base station 19-2 as the destination base station and base station 19-1 as the source base station. The optical path control unit 231 transmits optical path control information, including information indicating the determined source base station and destination base station, to the transfer device 13 and the optical transfer device 14k (step S511).

[0297] As a result, the transfer device 13 and the optical transfer device 14k switch the optical path that was formed between the base station 19-1, the first optical transceiver 131-1 and the second optical transceiver 132-1 of the transfer device 13, the first optical transceiver 142-1 and the second optical transceiver 143-1 of the optical transfer device 14k, and the core device 17, so that the optical path becomes a path that goes through the base station 19-2, the first optical transceiver 131-2 and the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 and the second optical transceiver 143-2 of the optical transfer device 14k, and the core device 17. At this point, the optical path control unit 231 may transmit an optical path control instruction to the base station that initiated the switching of the determined optical path.

[0298] The sleep control unit 232 identifies the devices to be put into sleep mode based on the sleep instructions included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the base station 19-1, the first optical transceiver 131-1 and the second optical transceiver 132-1 of the transfer device 13, and the first optical transceiver 142-1 and the second optical transceiver 143-1 of the optical transfer device 14k as devices to be put into sleep mode. The sleep control unit 232 sends sleep permission notifications to the identified base station 19-1, the optical transfer device 14k, and the transfer device 13 (step S511).

[0299] As a result, base station 19-1 enters sleep mode. Furthermore, optical transmission device 14k enters sleep mode for the first optical transceiver 142-1 and the second optical transceiver 143-1, which are identified by the information indicating the optical transceivers to be put into sleep mode included in the sleep permission notice. Furthermore, transmission device 13 enters sleep mode for the first optical transceiver 131-1 and the second optical transceiver 132-1, which are identified by the information indicating the optical transceivers to be put into sleep mode included in the sleep permission notice.

[0300] Although Figure 21 shows a configuration in which sleep control is performed after the optical path switching control is performed, the optical path switching control may also be performed after the sleep control is performed.

[0301] [Sleep Wake-up Process] Figure 22 is a flowchart showing an example of the sleep wake-up process performed by the management control device 20 in the third embodiment. Here, we will explain using the example of two base stations 19 (for example, base stations 19-1 to 19-2) and using traffic information as cooperation information. For further simplification of the explanation, in the configuration shown in Figure 20, we will assume that the first optical transceiver 131-2 and second optical transceiver 132-2 of base station 19-2 and transfer device 13, and the first optical transceiver 142-2 and second optical transceiver 143-2 of optical transfer device 14k are in a sleep state.

[0302] The information analysis unit 222 acquires the latest cooperation information for each base station 19 stored in the information storage unit 221 (step S601). In the management control device 20, cooperation information is collected at predetermined intervals or at arbitrary timings until the process shown in Figure 22 is executed. Therefore, the information storage unit 221 stores cooperation information for each base station 19 at predetermined intervals or at arbitrary timings. When the process shown in Figure 22 is started, the information analysis unit 222 acquires the latest cooperation information for each base station 19 at the start of the process shown in Figure 22.

[0303] The information analysis unit 222 calculates the traffic volume for each of the base stations 19-1 to 19-2 based on the latest acquired cooperation information for each base station 19 (step S602). The information analysis unit 222 compares the traffic volume for each of the base stations 19-1 to 19-2 with a threshold. The threshold used here may be the same as or different from the threshold used in Figure 21.

[0304] The information analysis unit 222 determines whether or not there are any base stations 19 whose traffic volume exceeds the threshold (step S603). If the information analysis unit 222 determines that there are no base stations 19 whose traffic volume exceeds the threshold (step S603-NO), the management control device 20 terminates the process shown in Figure 22.

[0305] On the other hand, if the information analysis unit 222 determines that there is a base station 19 whose traffic volume exceeds a threshold (step S603-YES), the information analysis unit 222 determines the base station 19 to be woken from sleep mode (step S604). Here, let's assume that the base station 19 whose traffic volume exceeds the threshold is base station 19-1. The information analysis unit 222 identifies the other base station 19 with the largest traffic volume among the traffic volume aggregated to base station 19-1 from among the sleeping base stations 19. The identification method is either (identification method 1) or (identification method 2) as shown in the first embodiment.

[0306] Assume that base station 19-2 is identified as the other base station 19 with the highest traffic volume by one of the identification methods described above. The information analysis unit 222 determines that the identified base station 19-2 is the base station 19 to be woken from sleep mode. Base station 19-1, whose traffic volume exceeds the threshold, is the source base station, and base station 19-2, which has been determined to be woken from sleep mode, is the destination base station.

[0307] Subsequently, the information analysis unit 222 determines the optical path control section based on the determined source base station (e.g., base station 19-1) and destination base station (e.g., base station 19-2) (step S605). For example, the information analysis unit 222 determines the section connecting each of the base stations 19-1 to 19-2 to the optical transmission device 14k as the optical path control section. Then, the information analysis unit 222 identifies either the sleep-state first optical transceiver 131 or sleep-state second optical transceiver 132 of the transmission device 13 to be used after the optical path switching in the determined optical path control section, or the sleep-state first optical transceiver 142 or sleep-state second optical transceiver 143 of the optical transmission device 14k.

[0308] In the above example, a portion of the traffic aggregated by base station 19-1 will be distributed to base station 19-2. When base station 19-2 is woken from sleep mode in this way, the optical paths that need to be newly generated are the paths from base station 19-2, the first optical transceiver 131-2 of the transfer device 13, the second optical transceiver 132-2 of the transfer device 13, the first optical transceiver 142-2 of the optical transfer device 14k, and the second optical transceiver 143-2 of the optical transfer device 14k.

[0309] Therefore, the sleep-state first optical transceiver 131-2 and sleep-state second optical transceiver 132-2 of the transfer device 13, and the sleep-state first optical transceiver 142-2 and sleep-state second optical transceiver 143-2 of the optical transfer device 14k will be used. Accordingly, the information analysis unit 222 also decides that the sleep-state first optical transceiver 131-2 and sleep-state second optical transceiver 132-2 of the transfer device 13, and the sleep-state first optical transceiver 142-2 and sleep-state second optical transceiver 143-2 of the optical transfer device 14k will also be subject to sleep mode activation (step S606). In this way, the information analysis unit 222 decides that not only the sleep-state base station 19, but also any of the sleep-state optical transceivers of the transfer device 13 or the optical transfer device 14k will also be subject to sleep mode activation.

[0310] Subsequently, the information analysis unit 222 notifies the control unit 23 of control information including an optical path control instruction and a sleep wake-up instruction. The information analysis unit 222 includes, for example, information indicating the switching destination base station (e.g., base station 19-2) in the optical path control instruction. Furthermore, the information analysis unit 222 includes, for example, information indicating the devices to be woken from sleep mode (e.g., base station 19-2, the sleep-state first optical transceiver 131-2 and sleep-state second optical transceiver 132-2 of the transfer device 13, and the sleep-state first optical transceiver 142-2 and sleep-state second optical transceiver 143-2 of the optical transfer device 14k) in the sleep wake-up instruction.

[0311] The optical path control unit 231 identifies the switching destination base station based on the optical path control instructions included in the control information notified by the information analysis unit 222. Here, the optical path control unit 231 determines base station 19-2 as the switching destination base station. The optical path control unit 231 transmits optical path control information, which includes information indicating the determined switching destination base station, to the transfer device 13 and the optical transfer device 14k (step S607).

[0312] As a result, the transfer device 13 and the optical transfer device 14k switch the optical path route so that it goes from the base station 19-2 to the core device 17. The sleep control unit 232 identifies the devices to be woken from sleep based on the sleep wake-up instruction included in the control information notified by the information analysis unit 222. For example, the sleep control unit 232 identifies the base station 19-2, the sleep-state first optical transceiver 131-2 and sleep-state second optical transceiver 132-2 of the transfer device 13, and the sleep-state first optical transceiver 142-2 and sleep-state second optical transceiver 143-2 of the optical transfer device 14k as devices to be woken from sleep. The sleep control unit 232 transmits sleep wake-up instructions to the identified base station 19-2, the optical transfer device 14k, and the transfer device 13 (step S608).

[0313] As a result, base station 19-2 wakes up from sleep mode. Furthermore, optical transmission device 14k wakes up the sleep mode of the first optical transceiver 142-2 and the second optical transceiver 143-2, which are identified by the information indicating the optical transceiver to be woken up in the sleep wake instruction. Furthermore, transmission device 13 wakes up the sleep mode of the first optical transceiver 131-2 and the second optical transceiver 132-2, which are identified by the information indicating the optical transceiver to be woken up in the sleep wake instruction. As a result, base station 19-2, the optical transceiver in transmission device 13, and the optical transceiver in optical transmission device 14k can be woken up from sleep mode.

[0314] According to the mobile NW system 100 in the third embodiment configured as described above, the management control device 20 includes a collection unit 21 that acquires cooperation information from a plurality of base stations 19, an analysis unit 22 that determines which base station 19 to put into sleep mode from among the plurality of base stations 19 based on the cooperation information, and, based on the determined base station 19, causes at least one of the optical transceivers provided in the transfer device 13 or the optical transceiver provided in the optical transfer device 14k to execute sleep control on the base station 19 to be put into sleep mode.

[0315] This allows not only the base station 19 but also at least one of the optical transceivers in the transmission device 13 or the optical transceiver in the optical transmission device 14k to be put into sleep mode. As a result, it becomes possible to improve the power saving effect of the entire system compared to conventional methods.

[0316] (Modification 1 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 is shown to perform optical path control processing and sleep control processing. In contrast, the transfer device may be configured to perform optical path control processing and sleep control processing. In this configuration, the mobile NW system 200 is equipped with a transfer device 13a shown in Figure 5 instead of the transfer device 13, and a management control device 20a shown in Figure 5 instead of the management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0317] (Modification 2 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical transmission device may be configured to perform optical path control processing and sleep control processing. In this configuration, the mobile NW system 200 includes the optical transmission device 14b shown in Figure 6 instead of the optical transmission device 14k, and the management control device 20b shown in Figure 6 instead of the management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0318] (Modification 3 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the transmission device may be configured to perform sleep control processing and the optical transmission device may perform optical path control processing. In this configuration, the mobile NW system 200 includes a transmission device 13c shown in Figure 7 instead of a transmission device 13, an optical transmission device 14c shown in Figure 7 instead of an optical transmission device 14k, and a management control device 20c shown in Figure 7 instead of a management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0319] (Modification 4 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the transfer device to perform optical path control processing. In this configuration, the mobile NW system 200 includes a transfer device 13d shown in Figure 8 instead of the transfer device 13, and a management control device 20d shown in Figure 8 instead of the management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0320] (Modification 5 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the management control device may be configured to perform sleep control processing and the optical transmission device to perform optical path control processing. In this configuration, the mobile NW system 200 is equipped with an optical transmission device 14e shown in Figure 9 instead of the optical transmission device 14k, and a management control device 20e shown in Figure 9 instead of the management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0321] (Modification 6 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. In this configuration, the mobile NW system 200 includes an optical transmission management control device 65 and a wireless transmission management control device 70 as shown in Figure 10 instead of the management control device 20. For specific processing, the wireless station 12 and distributed station 15 can be read as base station 19.

[0322] (Modification 7 in the third embodiment) In the configuration shown in Figure 20, the management control device 20 performs optical path control processing and sleep control processing. In contrast, the optical path control processing and sleep control processing may be performed by different devices. In this configuration, the mobile NW system 200 includes an optical transmission management control device 65 and a wireless transmission management control device 70 as shown in Figure 11 instead of the management control device 20. For specific processing, the wireless station 12 and distributed station 15 can be read as base station 19.

[0323] (Modification 8 in the third embodiment) The mobile NW system 200 may be configured as shown in Figure 12. In this configuration, the mobile NW system 200 includes an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75 as shown in Figure 12, instead of the management control device 20. For specific processing, the wireless station 12 and distributed station 15 can be read as base station 19.

[0324] (Modification 9 in the third embodiment) The mobile NW system 200 may be configured as shown in Figure 13. In this configuration, the mobile NW system 200 includes an optical transmission management control device 65, a wireless transmission management control device 70, and an orchestrator 75 as shown in Figure 13, instead of the management control device 20. For specific processing, the wireless station 12 and distributed station 15 can be read as base station 19.

[0325] (Modification 10 in the third embodiment) The mobile NW system 200 may be configured as shown in Figure 14. In this configuration, the mobile NW system 200 includes an optical transmission management control device 65 and a wireless transmission management control device as shown in Figure 14, instead of the management control device 20. For specific processing, the radio station 12 and distributed station 15 can be read as base station 19.

[0326] (Modification 11 in the third embodiment) The cooperation information may include, for example, information on the number of terminals accommodated by each base station 19. The cooperation information may include, for example, processing load information of the base station 19. The processing load information in the third embodiment may be, for example, information on the memory usage rate or CPU usage rate of the base station 19. The cooperation information may include communication quality information of the terminals 11 connected to each base station 19.

[0327] If the linked information includes information about the number of connected terminals, the information analysis unit 222 may use the information about the number of connected terminals to select the base stations to be controlled to sleep (for example, those to be controlled to sleep or those to be woken up). In this configuration, the information analysis unit 222 can select the base stations to be controlled to sleep in the same way as when using traffic information.

[0328] First, the information analysis unit 222 sorts each base station 19 in descending order of the number of connected terminals identified by the information regarding the number of connected terminals. Then, the information analysis unit 222 adds up the number of connected terminals in ascending order to the base station 19 with the fewest connected terminals. The information analysis unit 222 compares the summed total with a threshold and continues adding up the number of connected terminals in ascending order until it exceeds the threshold. Based on the number of connected terminals added up to the point before exceeding the threshold, the information analysis unit 222 selects a base station to be put into sleep mode from among the multiple base stations 19 related to the summed number of connected terminals. Next, the information analysis unit 222 determines the base station to be aggregated from among the multiple base stations 19 related to the summed number of connected terminals. For example, the information analysis unit 222 determines the base station with the most connected terminals among the summed number of connected terminals within the range that does not exceed the threshold as the base station 19 to be aggregated. Then, the information analysis unit 222 determines the base stations 19 other than the aggregation target to be put into sleep mode from among the multiple base stations 19 related to the summed number of connected terminals.

[0329] If the linked information includes processing load information or communication quality information, the information analysis unit 222 may select sleep control targets (e.g., sleep targets or sleep wake targets) using the processing load information or communication quality information in addition to the traffic information. For example, when selecting sleep control targets using communication quality information in addition to traffic information, the information analysis unit 222 determines to perform sleep control if the conditions based on the traffic information and the conditions based on the communication quality information are met. The conditions based on the communication quality information may be, for example, conditions based on whether the route after sleep is feasible (e.g., whether quality degradation occurs). In this case, even if the information analysis unit 222 determines the base stations 19 that are sleep targets and optical path control targets based on the conditions based on the traffic information, it is possible that quality may degrade after the route is switched. Therefore, even if the information analysis unit 222 determines the base stations 19 that are sleep targets and optical path control targets based on the conditions based on the traffic information, it may choose not to perform sleep if quality degrades in the route after optical path control.

[0330] (Fourth Embodiment) The first to third embodiments described above used a mobile network system as an example. The fourth embodiment uses a wired network system as an example.

[0331] (Overall Configuration and Processing Overview of Wired Network System) Figure 23 is a diagram illustrating the overall configuration and processing overview of the wired network system in the fourth embodiment. First, the overall configuration of the wired network system will be described. A wired network system is an example of a communication system. A wired network system is, for example, a PON (Passive Optical Network). In the following description, the case where the wired network system is a PON will be described, but the wired network system may have other configurations as long as the terminals are connected by wires. For example, the wired network system may have a configuration in which the terminals are connected point-to-point. The wired network system comprises an ONU 42, an optical transmission device 44, an OLT 45, a concentrator 46, a core device 47, a server 48, and a management control device 50.

[0332] Each ONU 42 is connected to the optical transfer device 44, the optical transfer device 44 to the OLT 45, the OLT 45 to the concentrator 46, the concentrator 46 to the core device 47, and the core device 47 to the server 48 by optical fiber for transmitting optical signals. The optical transfer device 44 is connected to the management control device 50, and each OLT 45 is connected to the management control device 50 by either a control line (e.g., an electric wire) or an optical fiber for transmitting control signals.

[0333] The example shown in Figure 23 illustrates a wired network system comprising one optical transmission device 44 and two OLTs 45-1 to 45-2. The number of ONUs 42, optical transmission devices 44, OLTs 45, concentrators 46, core devices 47, and servers 48 in the wired network system is not particularly limited.

[0334] In Figure 23, one optical transfer device 44 is positioned in the direction from the ONU 42 towards the server 48 (upstream direction), but multiple optical transfer devices 44 may be arranged in a series (for example, optical transfer device 44-1, optical transfer device 44-2, ...).

[0335] The ONU 42 is an optical subscriber line termination device installed in the user's home that terminates optical signals. One or more terminals 41 are connected to each ONU 42 by wires such as electrical lines. Each ONU 42 communicates with the terminals 41 via wires. For example, each ONU 42 receives an uplink signal transmitted from the terminal 41 and converts the received uplink signal into an optical signal. The ONU 42 transmits the converted optical signal to the destination OLT 45 via the optical transfer device 44. The ONU 42 receives an optical signal via the optical transfer device 44. The ONU 42 converts the received optical signal into an electrical signal and transmits it to the destination terminal 41.

[0336] The optical transfer device 44 is provided between the ONU 42 and the OLT 45. The optical transfer device 44 is, for example, an optical switch or a ROADM. The optical transfer device 44 transfers optical signals transferred from the ONU 42 to the destination OLT 45, or transfers optical signals transmitted from the OLT 45 to the destination ONU 42.

[0337] The optical transfer device 44 controls the optical path according to the optical path control information transmitted from the management control device 50. For example, the optical path control performed by the optical transfer device 44 includes switching optical paths and forming new optical paths. By controlling the optical path, the optical transfer device 44 controls the connection between the ONU 42 and the OLT 45. For example, when the optical transfer device 44 receives optical path control information transmitted from the management control device 50, it performs a switch so that the optical path is connected between the ONU 42 and the OLT 45, which are the destinations of the optical path switch.

[0338] Furthermore, the optical transmission device 44 transitions the optical transceiver specified by the sleep instruction to a sleep state in accordance with the sleep instruction transmitted from the management control device 50. The optical transceiver specified by the sleep instruction is, for example, an optical transceiver that will no longer be used due to the switching of an optical path. An optical transceiver that will no longer be used is an optical transceiver that does not need to be made usable and is therefore an optical transceiver that is subject to sleep mode.

[0339] Furthermore, the optical transmission device 44 wakes the optical transceiver specified by the sleep wake instruction in accordance with the sleep wake instruction transmitted from the management control device 50. The optical transceiver specified by the sleep wake instruction is, for example, an optical transceiver used by switching optical paths. The optical transceiver used is an optical transceiver that needs to be made usable and is the optical transceiver to be woken from sleep. The optical transmission device 44 is one embodiment of other devices and relay devices.

[0340] As described above, the optical transfer device 44 is a device that controls the optical path for connecting the ONU 42 and the OLT 45.

[0341] OLT 45 is an optical subscriber line terminal device installed on the electric utility side that terminates optical signals. OLT 45 receives uplink signals transmitted by one or more ONUs 42 via the optical transfer device 44. OLT 45 transmits downlink signals to one or more ONUs 42 connected via the optical transfer device 44. The uplink signals transmitted by one or more ONUs 42 are signals converted from signals transmitted by terminal 41 into optical signals, and the downlink signals are optical signals destined for terminal 41. OLT 45 transitions to a sleep state in accordance with a sleep instruction transmitted from the management control device 50. The information acquired by the management control device 50 from OLT 45 is called cooperation information. In the fourth embodiment, the cooperation information is information indicating the communication status between each OLT 45 and terminal 41.

[0342] The collaborative information in the fourth embodiment includes, for example, information on the traffic volume of each OLT 45. The traffic information is the same as in the first embodiment.

[0343] The OLT 45 comprises at least a transmitting unit, a receiving unit, and a sleep processing unit. The transmitting unit transmits cooperation information to the management control device 50 at the request of the management control device 50 or voluntarily. The receiving unit receives a sleep permission notification from the management control device 50. In response to receiving the sleep permission notification, the sleep processing unit puts the OLT 45 (itself) into a sleep state.

[0344] The concentrator 46 aggregates the uplink signals transmitted by each OLT 45. The concentrator 46 distributes the downlink signals.

[0345] The core device 47 performs signal processing on the uplink signals aggregated by the concentrator 46. The core device 47 transmits the signal obtained as a result of performing signal processing on the uplink signals to the server 48. The core device 17 performs predetermined signal processing on the signals received from the server 48. The core device 47 transmits the signal obtained as a result of performing signal processing on the signals received from the server 48 to the concentrator 46 as a downlink signal.

[0346] Server 48 transmits signals sent from core device 47 to the external network. Server 48 transmits signals received from the external network to core device 47.

[0347] The management control device 50 is a device that manages the entire wired network system. The management control device 50 acquires coordination information from each OLT 45. When acquiring coordination information from each OLT 45, the management control device 50 uses a coordination interface. Based on the acquired coordination information, the management control device 50 determines whether or not optical path control and sleep control are necessary.

[0348] For example, the management control device 50 may determine that control of the optical path is necessary when it determines that sleep control is possible. The management control device 50 performs optical path control processing and sleep control processing when it determines that sleep control is necessary. The optical path control processing in the fourth embodiment is the process of switching the optical path between the ONU 42 and the OLT 45 or generating an optical path. The sleep control processing in the fourth embodiment is the process of executing sleep or releasing the sleep state for the device to be controlled for sleep. In the fourth embodiment, the device to be controlled for sleep is the optical transceiver of the optical transfer device 44 and the OLT 45.

[0349] During optical path control processing, the management control device 50 determines whether or not there are optical transceivers in the optical transfer device 44 that will not be used for signal transfer after the optical path is switched. If there are optical transceivers in the optical transfer device 44 that will not be used for signal transfer after the optical path is switched, the management control device 50 determines that one of the optical transceivers in the unused optical transfer device 44 is a target for sleep control. The management control device 50 then sends a sleep instruction to the optical transfer device 44 that has the unused optical transceiver. If there are no optical transceivers in the optical transfer device 44 that will not be used for signal transfer after the optical path is switched, the management control device 50 does not determine that the optical transfer device 44 is a target for sleep control.

[0350] Furthermore, during optical path control processing, the management control device 50 determines whether or not there are optical transceivers in the sleep-state optical transfer device 44 that will be used for signal transfer after the optical path is switched. If there are optical transceivers in the sleep-state optical transfer device 44 that will be used for signal transfer after the optical path is switched, the management control device 50 determines that one of the optical transceivers in the sleep-state optical transfer device 44 that will be used is subject to sleep control. The management control device 50 then sends a sleep-release instruction to the optical transfer device 44 that has the optical transceiver in sleep state that will be used. If there are no optical transceivers in the sleep-state optical transfer device 44 that will be used for signal transfer after the optical path is switched, the management control device 50 does not determine that the sleep-state optical transfer device 44 is subject to sleep control. The management control device 50 is one embodiment of the control device.

[0351] Next, we will explain the overview of the wired network system's processing. The upper diagram of Figure 23 shows the connection status of the wired network system before optical path switching, and the lower diagram of Figure 23 shows the connection status of the wired network system after optical path switching. In the upper diagram of Figure 23, it is assumed that ONU 42-1 is connected to OLT 45-1 and ONU 42-2 is connected to OLT 45-2.

[0352] The management control device 50 determines, based on the coordination information collected from each OLT 45, that sleep control is possible if one OLT 45 can accommodate the traffic of the other OLT 45s. In other words, the management control device 50 performs optical path control processing and sleep control processing if, based on the coordination information collected from each OLT 45, one OLT 45 can accommodate the traffic of the other OLT 45s. In this way, by accommodating the traffic of the other OLT 45s to one OLT 45, the other OLT 45s that have no traffic can be put into sleep mode.

[0353] When the management control device 50 performs optical path control processing, it instructs the optical transfer device 44 to switch the optical path. The management control device 50 determines the path after the optical path switch during the optical path control processing. Therefore, the management control device 50 can identify the optical transceivers of the optical transfer device 44 that will not be used after the optical path switch in the section between the ONU 42 and the OLT 45.

[0354] For example, as shown in the lower diagram of Figure 23, the management control device 50 determines that OLT 45-1 can be put into sleep mode if OLT 45-2 can accommodate all the traffic from OLT 45-1. Then, in the optical path control processing, the management control device 50 transmits optical path control information to the optical transfer device 44 instructing it to switch the path from ONU 42-1 to OLT 45-1 to the path from ONU 42-1 to OLT 45-2. OLT 45-1 and OLT 45-2 are connected to different optical transceivers provided by the optical transfer device 44. Therefore, the management control device 50 transmits optical path control information to the optical transfer device 44 instructing it to switch the connection so that the destination of ONU 42-1 is the optical transceiver provided by the optical transfer device 44 that is connected to OLT 45-2.

[0355] As a result, the optical transceiver of the optical transmission device 44 connected to OLT 45-1 is not used in the path after the optical path is switched. Therefore, the management control device 50 determines that the optical transceiver of the optical transmission device 44 connected to OLT 45-1 is not used in the path after the optical path is switched. The management control device 50 then determines that the optical transceiver of the optical transmission device 44 connected to OLT 45-1 is also capable of sleep control.

[0356] In addition, the optical transmission device 44 may need to switch optical paths. In such cases, the management control device 50 will also send an instruction to the optical transmission device 44 to switch optical paths. After the optical path switch is complete, the optical transmission device 44 will notify the management control device 50 that the optical path switch has been completed. Since the connection destination of the terminal 41 will change due to the optical path switch, the management control device 50 may also instruct the OLT 45, which is the target of the optical path switch, to change its connection.

[0357] When the management control device 50 receives notification of completion of optical path switching from the device to be switched (for example, the optical transceiver of the optical transfer device 44), it sends a sleep permission notification to the devices that can enter sleep mode. In the example shown in the lower part of Figure 23, the management control device 50 determines that the OLT 45-1 and the optical transceiver of the optical transfer device 44 are devices that can enter sleep mode. Therefore, the management control device 50 sends a sleep permission notification to the optical transceiver of the optical transfer device 44 and the OLT 45-1.

[0358] The lower diagram in Figure 23 shows an example where ONUs 42-1 to 42-2 are connected to OLT 45-2, and OLT 45-1 and the optical transceiver of the optical transmission device 44 connected to OLT 45-1 have entered a sleep state. Based on the cooperation information collected from each OLT 45, the management control device 50 moves devices that can enter a sleep state into a sleep state by connecting terminals 41 connected to OLT 45s that can enter a sleep state to other OLT 45s.

[0359] By putting OLT45 into sleep mode, the optical path directed to OLT45 is switched. For example, if terminal 41 connected to OLT45-1, which can enter sleep mode, is to be connected to OLT45-2, the optical path directed to OLT45-1 will be switched to be directed to OLT45-2. In this way, by putting OLT45 into sleep mode, the optical path directed to OLT45 is switched. Hereafter, OLT45 that can enter sleep mode will be referred to as the source OLT, and OLT45 that becomes the new connection destination for terminal 41 connected to the source OLT will be referred to as the destination OLT.

[0360] (Details of the fourth embodiment) Figure 24 shows an example of the configuration of the wired network system 300 in the fourth embodiment. The wired network system 300 in the fourth embodiment includes an ONU 42, an optical transmission device 44, an OLT 45, a concentrator 46, a core device 47, a server 48, and a management control device 50. The ONU 42, OLT 45, concentrator 46, core device 47, and server 48 were explained in Figure 23, so their explanation is omitted here.

[0361] The optical transmission device 44 includes a first optical transceiver 441 and a second optical transceiver 442. In Figure 24, for the sake of simplicity, the optical transmission device 44 is shown to have a configuration comprising two first optical transceivers 441-1 to 441-2 and two second optical transceivers 442-1 to 442-2, but the number of first optical transceivers 441 and second optical transceivers 442 is not particularly limited.

[0362] The first optical transceiver 441 transmits and receives signals with the ONU 42. The first optical transceiver 441 forwards the optical signal transmitted from the ONU 42 to the second optical transceiver 442, which is the transfer destination. The first optical transceiver 441 also forwards the optical signal transmitted from the second optical transceiver 442 to the connected ONU 42.

[0363] The second optical transceiver 442 transmits and receives signals with the OLT 45. The second optical transceiver 442 forwards the optical signal transmitted from the first optical transceiver 441 to the connected OLT 45. The second optical transceiver 442 also forwards the optical signal transmitted from the connected OLT 45 to the first optical transceiver 441, which is the forwarding destination.

[0364] [Configuration of the Management Control Device 50] Next, the configuration of the management control device 50 in the fourth embodiment will be described. The management control device 50 includes a collection unit 51, an analysis unit 52, and a control unit 53. The collection unit 51, the analysis unit 52, and the control unit 53 perform the same processing as the collection unit 21, the analysis unit 22, and the control unit 23 in the first embodiment, except that the target is different.

[0365] [Sleep Processing] Figure 25 is a flowchart showing an example of the sleep processing flow performed by the management control device 50 in the fourth embodiment. Here, we will explain using the example of two OLTs 45 (for example, OLTs 45-1 to 45-2) and using traffic information as the coordination information. Furthermore, for the sake of simplicity, we will assume that the connection configuration of each device is as shown in Figure 24.

[0366] The information analysis unit 522 acquires the latest linkage information for each OLT 45 stored in the information storage unit 521 (step S701). In the management control device 50, linkage information is collected at predetermined intervals or at arbitrary timings until the process in Figure 25 is executed. Therefore, the information storage unit 521 stores linkage information for each OLT 45 at predetermined intervals or at arbitrary timings. Thus, when the process in Figure 25 is started, the information analysis unit 522 acquires the latest linkage information for each OLT 45 at the start of the process in Figure 25.

[0367] The information analysis unit 522 calculates the traffic volume for each of the OLTs 45-1 to 45-2 based on the latest acquired linkage information for each OLT 45. Then, the information analysis unit 522 sorts the OLTs 45-1 to 45-2 in ascending order of their calculated traffic volumes (step S702).

[0368] The information analysis unit 522 determines the traffic volume to be added to A (step S703). In the fourth embodiment, the traffic volume to be added to A is, for example, OLT45 with the least traffic volume. For example, here we will call the OLT45 with the least traffic volume OLT45-1. Next, the information analysis unit 522 determines the traffic volume to be added to B (step S704). In the fourth embodiment, the traffic volume to be added to B is, for example, OLT45 with the second least traffic volume OLT45. For example, here we will call the OLT45 with the second least traffic volume OLT45-2. The information analysis unit 522 adds the traffic volume of the traffic volume to be added to A and the traffic volume of the traffic volume of B to obtain the traffic volume addition value T ｔｏｔａｌ Calculate (step S705).

[0369] The information analysis unit 522 calculates the traffic volume sum value T. ｔｏｔａｌ The calculated traffic volume sum T is compared with the threshold value. Here, the threshold value is a value for control decision, and may be the same value for each OLT 45, or it may be a different value for each OLT 45. The threshold value may be calculated by the information analysis unit 522 based on the linked information and recorded in the information storage unit 521, or it may be stored in advance by the information analysis unit 522 for each OLT 45. If the threshold value for each OLT 45 is recorded in the information storage unit 521, the information analysis unit 522 may read and use the threshold value recorded in the information storage unit 521. The information analysis unit 522 calculates the traffic volume sum value T ｔｏｔａｌ Then, compare this with the threshold value of OLT45 corresponding to item A that needs to be added.

[0370] The information analysis unit 522 calculates the traffic volume sum value T. ｔｏｔａｌ However, it is determined whether or not it is greater than the threshold (step S706). The information analysis unit 522 determines whether the traffic volume sum value T ｔｏｔａｌ However, if it is determined that the amount is not greater than the threshold (step S706-NO), the information analysis unit 522 adds the smallest traffic amount among the traffic amounts that have not been added, thereby creating a new traffic amount addition value T ｔｏｔａｌ Calculate (step S707).

[0371] Subsequently, the information analysis unit 522 executes the process in step S706 again. In this case, the information analysis unit 522 calculates the newly calculated traffic volume sum value T. ｔｏｔａｌ However, it is determined whether or not it is greater than the threshold (step S706). Note that there may be cases where there is no traffic volume that has not been added. If there is no traffic volume that has not been added, the information analysis unit 522 may execute the process in step S708.

[0372] The information analysis unit 522 calculates the traffic volume sum value T. ｔｏｔａｌ If it is determined that the traffic volume is greater than the threshold (step S706 - YES), or if there is no traffic volume that has not been added, the information analysis unit 522 determines the OLT 45 to be aggregated. Specifically, the information analysis unit 522 may determine the OLT 45 with the largest traffic volume from among the OLT 45s that have each traffic volume that has been added up to the time before the processing in step S708 is executed (for example, before the threshold is exceeded, or before there is no more traffic volume that has not been added), and select the OLT 45 with the largest traffic volume as the OLT 45 to be aggregated.

[0373] For example, if each OLT 45 with the summed traffic volume before executing the process in step S708 is OLT 45-1 to 45-2, the information analysis unit 522 may decide that the OLT 45 with the largest traffic volume among OLT 45-1 to 45-2 is the OLT 45 to be aggregated. Note that the method for determining the OLT 45 to be aggregated is not limited to the above method, and other methods may be used (for example, a method of deciding that the OLT 45 with the second largest traffic volume is the OLT 45 to be aggregated). Here, let's assume that OLT 45-2 is determined to be the aggregation destination.

[0374] Furthermore, the information analysis unit 522 determines which OLT 45 will be put to sleep (step S708). For example, the information analysis unit 522 determines that the OLT 45s other than the OLT 45 that became the aggregation destination will be put to sleep from among the OLT 45s with the respective traffic amounts added up to the time before the processing in step S708 is executed. In the above example, the OLT 45s with the respective traffic amounts added up to the time before the processing in step S108 are OLT 45-1 to 45-2, and the OLT 45 that became the aggregation destination is OLT 45-2. Therefore, the information analysis unit 522 determines that OLT 45-1 will be put to sleep. OLT 45-1, which has been determined to be put to sleep, is the source OLT, and OLT 45-2, which has been determined to be the aggregation destination, is the destination OLT.

[0375] Subsequently, the information analysis unit 522 determines the optical path control section based on the determined source OLT (e.g., OLT 45-1) and destination OLT (e.g., OLT 45-2) (step S709). For example, the information analysis unit 522 determines the optical path control section to connect ONU 42-1 to 42-2 and OLT 45-1 to 45-2, respectively.

[0376] In the example shown in Figure 24, the section connecting ONU 42-1 and OLT 45-1 consists of ONU 42-1, the first optical transceiver 441-1 of the optical transfer device 44, the second optical transceiver 442-1 of the optical transfer device 44, and OLT 45-1. Also in the example shown in Figure 24, the section connecting ONU 42-2 and OLT 45-2 consists of ONU 42-2, the first optical transceiver 441-2 of the optical transfer device 44, the second optical transceiver 442-2 of the optical transfer device 44, and OLT 45-2.

[0377] The information analysis unit 522 then identifies the optical transceiver that will no longer be used after the optical path is switched in the determined optical path control section. Specifically, the information analysis unit 522 identifies the optical transceiver that will no longer be used after the optical path is switched, among the first optical transceiver 441 and the second optical transceiver 442 provided in the optical transfer device 44.

[0378] In the above example, all the traffic aggregated by OLT45-1 will be aggregated to OLT45-2. In this case, the optical path will be switched from the path of the first optical transceiver 441-1 of the optical transfer device 44, the first optical transceiver 441-2 of the optical transfer device 44 and OLT45-1 to the path of the first optical transceiver 441-1 of the optical transfer device 44, the second optical transceiver 442-2 of the optical transfer device 44 and OLT45-2.

[0379] Therefore, the second optical transceiver 442-1 of the optical transfer device 44 will not be used. Accordingly, the information analysis unit 522 decides that the second optical transceiver 442-1 of the optical transfer device 44 will also be put into sleep mode (step S710).

[0380] Subsequently, the information analysis unit 522 notifies the control unit 53 of control information including an optical path control instruction and a sleep instruction. The information analysis unit 522 includes in the optical path control instruction information, for example, information indicating the source OLT (e.g., OLT 45-1), information indicating the destination OLT (e.g., OLT 45-2), and information indicating the ONU 42 to which the destination OLT will be connected. Furthermore, the information analysis unit 522 includes in the sleep instruction information indicating, for example, the devices to be put into sleep mode (e.g., OLT 45-1 and the second optical transceiver 442-1 of the optical transfer device 44).

[0381] The optical path control unit 531 identifies the source OLT and the destination OLT based on the optical path control instructions included in the control information notified by the information analysis unit 522. Here, the optical path control unit 531 determines OLT 45-2 as the destination OLT and OLT 45-1 as the source OLT. The optical path control unit 531 transmits optical path control information, including information indicating the determined source OLT and destination OLT, to the optical transfer device 44 (step S711).

[0382] As a result, the optical transfer device 44 switches the optical path from one leading to OLT 45-1 to one leading to OLT 45-2. The optical transfer device 44 forms an optical path to transfer the uplink signal transmitted from ONU 42-1 to OLT 45-2. At this point, the optical path control unit 531 may transmit optical path control instructions to the determined source OLT and the ONU 2 connected to the source OLT.

[0383] The sleep control unit 532 identifies the devices to be put into sleep mode based on the sleep instruction included in the control information notified by the information analysis unit 522. For example, the sleep control unit 532 identifies the OLT 45-1 and the second optical transceiver 442-1 of the optical transfer device 44 as devices to be put into sleep mode. The sleep control unit 532 sends a sleep permission notification to the identified OLT 45-1 and the optical transfer device 44 (step S712).

[0384] As a result, OLT 45-1 enters sleep mode. Furthermore, the optical transmission device 44 enters sleep mode the second optical transceiver 442-1, which is identified by the information indicating the optical transceiver to be put into sleep mode included in the sleep permission notification.

[0385] In Figure 25, a configuration is shown in which sleep control is performed after the optical path switching control is performed, but the optical path switching control may also be performed after the sleep control is performed. Furthermore, in Figure 25, a configuration is shown in which the sleep control unit 532 puts the second optical transceiver 442-1 and the OLT 45 of the optical transfer device 44 to sleep, but the sleep control unit 532 may put both the OLT 45 to be put to sleep and the ONU 42 connected to the OLT 45 to be put to sleep via the optical transfer device 44, or it may put only the ONU 42 to sleep.

[0386] [Sleep Wake-Up Process] Figure 26 is a flowchart showing an example of the sleep wake-up process performed by the management control device 50 in the fourth embodiment. Here, we will explain using the example of two OLTs 45 (for example, OLTs 45-1 to 45-2) and using traffic information as the cooperation information. For further simplification of the explanation, in the configuration shown in Figure 24, we will assume that ONUs 42-1 and 42-2 are connected to OLT 45-1 via the optical transfer device 44. We will also assume that OLT 45-2 and the second optical transceiver 442-2 provided in the optical transfer device 44 are in a sleep state.

[0387] The information analysis unit 522 acquires the latest linkage information for each OLT 45 stored in the information storage unit 521 (step S801). In the management control device 50, linkage information is collected at predetermined intervals or at arbitrary timings until the process in Figure 25 is executed. Therefore, the information storage unit 521 stores linkage information for each OLT 45 at predetermined intervals or at arbitrary timings. When the process in Figure 25 is started, the information analysis unit 522 acquires the latest linkage information for each OLT 45 at the start of the process in Figure 25.

[0388] The information analysis unit 522 calculates the traffic volume for each of the OLTs 45-1 to 45-2 based on the latest acquired linkage information for each OLT 45 (step S802). The information analysis unit 522 compares the traffic volume for each of the OLTs 45-1 to 45-2 with a threshold. The threshold used here may be the same as or different from the threshold used in Figure 25.

[0389] The information analysis unit 522 determines whether or not there are any OLT 45s whose traffic volume exceeds a threshold (step S803). If the information analysis unit 522 determines that there are no OLT 45s whose traffic volume exceeds a threshold (step S803-NO), the management control device 50 terminates the process shown in Figure 26.

[0390] On the other hand, if the information analysis unit 522 determines that there is an OLT 45 whose traffic volume exceeds a threshold (step S803-YES), the information analysis unit 522 determines which OLT 45 is to be woken from sleep mode (step S804). Here, let's assume that the OLT 45 whose traffic volume exceeds the threshold is OLT 45-1. The information analysis unit 522 identifies the other OLT 45 with the highest traffic volume among the traffic volumes aggregated to OLT 45-1 from among the sleeping OLT 45s. The identification method used is either (identification method 1) or (identification method 2) as shown in the first embodiment.

[0391] Assume that OLT45-2 is identified as the other OLT45 with the highest traffic volume using one of the identification methods described above. The information analysis unit 522 determines that the identified OLT45-2 is the OLT45 to be woken from sleep mode. OLT45-1, whose traffic volume exceeds the threshold, is the source OLT, and OLT45-2, which has been determined to be woken from sleep mode, is the destination OLT.

[0392] Subsequently, the information analysis unit 522 determines the optical path control section based on the determined source OLT (e.g., OLT 45-1) and destination OLT (e.g., OLT 45-2) (step S805). For example, the information analysis unit 522 determines the section connecting the ONU 42 and OLTs 45-1 to 45-2 as the optical path control section. Then, the information analysis unit 522 identifies either the sleep-state first optical transceiver 441 or the sleep-state second optical transceiver 442 to be used after the optical path switching in the determined optical path control section.

[0393] In the example above, a portion of the traffic aggregated by OLT45-1 (for example, traffic transmitted from ONU42-2) will be distributed to OLT45-2. The optical paths that need to be newly generated when OLT45-2 is woken from sleep mode are the paths between ONU42-2, the second optical transceiver 442-1 of the optical transfer device 44, the second optical transceiver 442-2 of the optical transfer device 44, and OLT45-2.

[0394] Therefore, the second optical transceiver 442-2 of the optical transmission device 44, which is in sleep mode, will be used. Accordingly, the information analysis unit 522 decides that the second optical transceiver 442-2 of the optical transmission device 44, which is in sleep mode, should also be woken from sleep mode (step S806).

[0395] In this way, the information analysis unit 522 determines that not only the OLT 45 in sleep mode, but also the optical transceiver of the optical transfer device 44 in sleep mode should be woken from sleep mode.

[0396] Subsequently, the information analysis unit 522 notifies the control unit 53 of control information including an optical path control instruction and a sleep wake-up instruction. The information analysis unit 522 includes, for example, information indicating the destination OLT (e.g., OLT 45-2) and information indicating the ONU 42 to which the destination OLT will be connected in the optical path control instruction. Here, let's assume that the ONU 42 to which the destination OLT will be connected is ONU 42-2. Furthermore, the information analysis unit 522 includes, for example, information indicating the devices to be woken from sleep (e.g., OLT 45-2 and the second optical transceiver 442-2 of the optical transfer device 44) in the sleep wake-up instruction.

[0397] The optical path control unit 531 identifies the target OLT based on the optical path control instructions included in the control information notified by the information analysis unit 522. Here, the optical path control unit 531 determines OLT 45-2 as the target OLT. The optical path control unit 531 transmits optical path control information to the optical transfer device 44, which includes information indicating the determined target OLT and information indicating the ONU 42 (for example, ONU 42-2) to which the target OLT will be connected (step S807).

[0398] As a result, the optical transfer device 44 switches the optical path from ONU 42-2 to OLT 45-1 so that it goes from ONU 42-2 to OLT 45-2. The optical transfer device 44 forms an optical path to transfer the uplink signal transmitted from ONU 42-2 to OLT 45-2. Specifically, the optical transfer device 44 forms an optical path between the first optical transceiver 441-2 and the second optical transceiver 442-2 so that the uplink signal transmitted from ONU 42-2 goes to OLT 45-2. In this way, the optical transfer device 44 switches the optical path. At this point, the optical path control unit 531 may transmit optical path control instructions to the determined destination OLT and the ONU 42 connected to the destination OLT.

[0399] The sleep control unit 532 identifies the devices to be woken from sleep based on the sleep wake-up instruction included in the control information notified by the information analysis unit 522. For example, the sleep control unit 532 identifies the OLT 45-2 and the second optical transceiver 442-2 of the optical transfer device 44 as devices to be woken from sleep. The sleep control unit 532 sends a sleep wake-up instruction to the identified OLT 45-2 and the optical transfer device 44 (step S808).

[0400] As a result, OLT 45-2 wakes up from sleep mode. Furthermore, the optical transfer device 44 wakes up the sleep mode of the second optical transceiver 442-2, which is identified by the information indicating the optical transceiver to be woken up in the sleep wake-up instruction. This allows both OLT 45-2, which is the target of sleep wake-up, and the optical transceiver equipped in the optical transfer device 44 to be woken up from sleep mode.

[0401] In Figure 26, the sleep control unit 532 is shown to release the sleep state of the second optical transceiver 442-2 and the OLT 45 provided in the optical transfer device 44. However, the sleep control unit 532 may release the sleep state of both the OLT 45 to be released and the ONU 42 connected to the OLT 45 via the optical transfer device 44, or it may release the sleep state of the ONU 42.

[0402] In the wired network system 300 configured as described above, the management control device 50 includes a collection unit 51 that acquires cooperation information from a plurality of OLTs 45, an analysis unit 52 that determines which OLTs 45 to put into sleep mode from among the plurality of OLTs 45 based on the cooperation information, and, based on the determined OLTs 45, causes one of the optical transceivers provided in the optical transmission device 44 to execute sleep control on the OLTs 45 to be put into sleep mode.

[0403] This allows not only the OLT 45 but also any of the optical transceivers in the optical transmission device 44 to be put into sleep mode. As a result, it becomes possible to improve the overall power saving effect of the system compared to conventional methods.

[0404] (Modification 1 in the fourth embodiment) The cooperation information may include, for example, information regarding the number of terminals accommodated for each OLT 45. The cooperation information may include, for example, processing load information for the OLT 45. In the fourth embodiment, the processing load information may include, for example, information regarding the memory usage rate or CPU usage rate of the OLT 45. The cooperation information may include communication quality information for the terminals 41 connected to each OLT 45.

[0405] If the linked information includes information about the number of connected terminals, the information analysis unit 522 may use the information about the number of connected terminals to select devices to be controlled for sleep (for example, devices to be controlled for sleep or devices to be disabled from sleep). In this configuration, the information analysis unit 522 can select the devices to be controlled for sleep in the same way as when using traffic information.

[0406] First, the information analysis unit 522 sorts each OLT 45 in descending order of the number of terminals it houses, as identified by the information regarding the number of terminals it houses. Then, the information analysis unit 522 adds up the terminals in ascending order to the OLT 45 with the fewest terminals. The information analysis unit 522 compares the summed total with a threshold and continues adding up the terminals in ascending order until it exceeds the threshold. Based on the number of terminals added up to the point before exceeding the threshold, the information analysis unit 522 selects a sleep target from among the multiple OLTs 45 related to the summed number of terminals. Next, the information analysis unit 522 determines the OLT to be aggregated from among the multiple OLTs 45 related to the summed number of terminals. For example, the information analysis unit 522 determines the OLT with the most terminals among the terminals that are aggregated within the range that does not exceed the threshold as the OLT 45 to be aggregated. Subsequently, the information analysis unit 522 determines, from among the multiple OLTs 45 related to the total number of connected terminals, to be put into sleep mode, except for the OLT 45 that is the aggregation destination. Furthermore, the information analysis unit 522 determines, to be put into sleep mode, the first optical transceiver 441 and the second optical transceiver 442, which are equipped in the optical transfer device 44 that will not be used after the optical path switching.

[0407] If the linked information includes processing load information or communication quality information, the information analysis unit 522 may select sleep control targets (for example, sleep targets or sleep wake targets) using the processing load information or communication quality information in addition to the traffic information. For example, when selecting sleep control targets using communication quality information in addition to traffic information, the information analysis unit 522 determines to perform sleep control if the conditions based on the traffic information and the conditions based on the communication quality information are met. The conditions based on the communication quality information may be, for example, conditions based on whether the route after sleep is feasible (for example, whether or not quality degradation occurs). In this case, even if the information analysis unit 522 determines the OLT 45 sleep targets and optical path control targets based on the conditions based on the traffic information, it is possible that quality may degrade after the route is switched. Therefore, even if the information analysis unit 522 determines the OLT 45 sleep targets and optical path control targets based on the conditions based on the traffic information, it may choose not to perform sleep if quality degrades in the route after optical path control.

[0408] (Modification 2 in the fourth embodiment) In the configuration shown in Figure 24, a plurality of optical transfer devices 55 may be arranged after the optical transfer device 44 as shown in Figure 27. Figure 25 is a diagram showing another example of the configuration of the wired NW system 300 in the fourth embodiment. The wired NW system 300 in the fourth embodiment includes an ONU 42, an optical transfer device 44, an optical transfer device 55, an OLT 45, a concentrator 46, a core device 47, a server 48, and a management control device 50. The ONU 42, OLT 45, concentrator 46, core device 47, and server 48 have been explained in Figure 23, so their explanation is omitted here.

[0409] Figure 25 shows the case where there are two ONU 42s, two OLTs, and two optical transmission devices 55s, but the number of ONU 42s, two OLTs, and two optical transmission devices 55s is not particularly limited. In the example shown in Figure 25, optical transmission device 55-1 is provided between the second optical transceiver 442-1 of optical transmission device 44 and the OLT 45-1, and optical transmission device 55-2 is provided between the second optical transceiver 442-2 of optical transmission device 44 and the OLT 45-2. The specific operation of the wired NW system 300 shown in Figure 27 is the same as the mobile NW system 100 shown in Figure 2, except that the names of the devices are different.

[0410] The optical transfer device 55 has the same functions as the optical transfer device 14 shown in Figure 2. With this configuration, for example, if the OLT 45-1 can be put into sleep mode, it becomes possible to put the second optical transceiver 442-2 of the optical transfer device 44 and the optical transfer device 55-1 into sleep mode.

[0411] (In each embodiment) At least some or all of the functional units of the management control devices 20, 20a, 20b, 20c, 20d, 20e, 50, some or all of the functional units of the transfer devices 13, 13a, 13c, 13d, some or all of the functional units of the optical transfer devices 14, 14b, 14c, 14e, 14k, 44, or some or all of the functional units of the OLT 45 are realized as software by a processor such as a CPU executing a program stored in a storage device and a storage unit having a non-volatile recording medium (non-temporary recording medium). The program may be recorded on a computer-readable non-temporary recording medium. A computer-readable non-temporary recording medium is, for example, a portable medium such as a flexible disk, a magneto-optical disk, ROM (Read Only Memory), or CD-ROM (Compact Disc Read Only Memory), or a storage device such as a hard disk built into a computer system.

[0412] At least some or all of the functional units of the management control devices 20, 20a, 20b, 20c, 20d, 20e, 50, some or all of the functional units of the transfer devices 13, 13a, 13c, 13d, 43, some or all of the functional units of the optical transfer devices 14, 14b, 14c, 14e, 14k, or some or all of the functional units of the OLT 45 may be implemented using hardware including electronic circuits (or circuits) such as LSI (Large Scale Integrated Circuit), ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), or FPGA (Field Programmable Gate Array).

[0413] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs and the like that do not depart from the spirit of this invention.

[0414] This invention can be applied to optical communication systems such as optical access systems.

[0415] 11, 41... Terminals, 12, 12-1 to 12-2... Radio stations, 13, 13a, 13c, 13d... Transfer devices, 14, 14-1 to 14-2, 14b, 14b-1 to 14b-2, 14c, 14c-1 to 14c-2, 14e, 14e-1 to 14e-2, 14k, 44, 55-1, 55-2... Optical transfer devices, 15, 15-1 to 15-2... Distributed stations, 16... Aggregation stations, 17, 47... Core devices, 18, 48... Servers, 19, 19-1 to 19-2... Base stations, 20, 20a, 20b, 20c, 20d, 20e, 50... Management and control devices, 21, 51... Data collection units, 22, 52... Analysis units 23, 23d, 23e, 53, 66, 71, 133, 133d, 141, 141e... Control unit, 42, 42-1 to 42-2... ONU, 45, 45-1 to 45-2... OLT, 46... Concentrator, 65... Optical transmission management control device, 70... Wireless transmission management control device, 75... Orchestrator, 131, 131-1 to 131-2, 142, 142-1 to 142-2, 441, 441-1 to 441-2... First optical transceiver, 132, 132-1 to 132-2, 143, 143-1 to 143-2, 442, 442-1 to 442-2... Second optical transceiver, 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h, 100i, 100j, 100k, 200... Mobile NW system, 211, 511, 671, 721... Acquisition unit, 221, 521, 681, 731... Information storage unit, 222, 522, 682, 732... Information analysis unit, 231... Optical path control unit, 232... Sleep control unit, 300... Wired NW system, 751... Signal transfer unit

Claims

1. A control device comprising: a collection unit that acquires cooperation information from multiple communication stations accommodating one or more terminals; and an analysis unit that determines one or more communication stations to be put into sleep mode from among the multiple communication stations based on the cooperation information, and performs sleep control on the determined one or more communication stations using other devices or some functions provided by the other devices.

2. The control device according to claim 1, wherein the analysis unit determines the other device or some of the functions of the other device that are subject to the sleep control in accordance with the switching of the communication path that occurs when the determined one or more communication stations are put into sleep mode.

3. The control device according to claim 2, wherein the analysis unit determines that the other device or some functions of the other device that will become unused in accordance with the switching of the communication path will be the target of the sleep control.

4. The control device according to claim 3, wherein the other device is one or more relay devices equipped with a plurality of transceivers for transferring signals between the one or more terminals and the plurality of communication stations, and the analysis unit determines the one or more relay devices, or some of the transceivers provided by the one or more relay devices, as targets for the sleep control.

5. The control device according to claim 3, wherein the other device is one or more relay devices located above the plurality of communication stations and equipped with a plurality of transceivers that transfer signals between the plurality of communication stations and the higher-level device, and the analysis unit determines the one or more relay devices, or some of the transceivers provided by the one or more relay devices, as the target of the sleep control.

6. The control device according to any one of claims 1 to 5, wherein the analysis unit determines one or more communication stations from among the plurality of communication stations to be released from sleep state based on the linked information, and based on the determined one or more communication stations, it causes the other devices in sleep state or some of the functions of the sleep state provided by the other devices, and the determined one or more communication stations to release from sleep state.

7. A control method comprising: obtaining cooperation information from multiple communication stations accommodating one or more terminals; determining one or more communication stations to be put into sleep mode from among the multiple communication stations based on the cooperation information; and, based on the determined one or more communication stations, causing another device or some of the functions provided by the other device to execute sleep control for the determined one or more communication stations.

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