Signal transfer system, optical transmission device, control device, and signal transfer method

Abstract

A signal transfer system according to the present invention comprises: an information acquisition unit that acquires, for each traffic flow, information about the priority of each traffic flow; a control determination unit that carries out optical path generation control for instructing the generation of a dedicated optical path for each of one or more optical transmission devices if it is determined, on the basis of the priority information acquired for each traffic flow, that a dedicated optical path for transferring a specific traffic flow among a plurality of traffic flows included in a plurality of terminals is necessary; and a control unit that generates a dedicated optical path according to the optical path generation control.　

Description

Signal transfer system, optical transmission device, control device, and signal transfer method

[0001] The present invention relates to a signal transfer system, an optical transmission device, a control device, and a signal transfer method.

[0002] A signal transfer system shown in Fig. 17 has been proposed. Fig. 17 is a diagram showing an example of the configuration of a conventional signal transfer system 1000. The signal transfer system 1000 includes a server 1, a plurality of optical transmission devices 2-1 to 2-4, a core node 3, a central station 4, a remote station 5, a radio station 6, and an orchestrator 7.

[0003] The server 1 communicates with one or more wireless terminals 8 connected to a wireless station 6. Multiple optical transmission devices 2-1 to 2-4 transfer signals between the devices. The optical transmission device 2-1 transfers signals, for example, between the server 1 and a core node 3. The optical transmission device 2-2 transfers signals, for example, between the core node 3 and a central office 4. The optical transmission device 2-3 transfers signals, for example, between the central office 4 and a distributed office 5. The optical transmission device 2-4 transfers signals, for example, between a distributed office 5 and a wireless station 6.

[0004] The core node 3, central station 4, and distributed station 5 are base stations that relay signals exchanged between the server 1 and the wireless terminal 8. The wireless station 6 performs wireless communication with the wireless terminal 8. The wireless station 6 transmits signals transferred from the optical transmission device 2-4 to the wireless terminal 8 and transfers signals received from the wireless terminal 8 to the optical transmission device. The orchestrator 7 controls each device (e.g., the optical transmission devices 2-1 to 2-4, the core node 3, the central station 4, the distributed station 5, and the wireless station 6) provided between the server 1 and the wireless terminal 8. The orchestrator 7 generates optical paths between each device by performing optical path generation control, which is control for causing the optical transmission devices 2-1 to 2-4 to generate optical paths for traffic flows.

[0005] Yuta Tanaka et al., "5G Core Network Technology Overview for Realizing 5G SA," NTT DOCOMO Technical Journal, Vol. 30, No. 4, 2023. "3GPP TS23.502 V18.1.1," 3GPP (registered trademark), 2023. Kazuto Shimizu et al., "5G Core Network Technology Overview for Realizing Voice Calls with SA," NTT DOCOMO Technical Journal, Vol. 30, No. 4, 2023. "3GPP TS23.501 V18.1.0," 3GPP (registered trademark), 2023.

[0006] In the wired section of a mobile communication network, when a network consisting only of optical transmission devices 2-1 to 2-4 is used, the network of optical transmission devices 2-1 to 2-4 is divided into four sections: server 1 to core node 3, core node 3 to central office 4, central office 4 to distributed office 5, and distributed office 5 to wireless station 6, resulting in four terminations. Conventionally, optical paths for these four network sections are allocated independently, and multiple traffic flows with the same destination are transferred in a mixed manner on the optical paths of each network section. However, when a specific traffic flow must meet strict latency requirements, the traffic flow passes through an optical path that is mixed with other traffic flows, resulting in increased latency due to traffic congestion within the same optical path. This problem is not limited to mobile communication systems, but also occurs in wireless communication systems other than mobile communication systems.

[0007] In view of the above circumstances, the present invention aims to provide a technology that can reduce delay while satisfying delay requirements, even when there is a specific traffic flow that needs to satisfy strict delay requirements among multiple traffic flows of one or more wireless terminals.

[0008] One aspect of the present invention is a signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices that forward signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device and that determines a priority for each traffic flow between the one or more terminals; a higher-level device that communicates with the one or more terminals via the one or more optical transmission devices and the core node; and a control device that controls each device, wherein the signal transfer system comprises: an information acquisition unit that acquires priority information for each traffic flow; a control decision unit that, when it is determined based on the priority information acquired for each traffic flow that a dedicated optical path is necessary for transferring a specific traffic flow among a plurality of traffic flows possessed by the one or more terminals, performs optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path; and a control unit that generates the dedicated optical path in accordance with the optical path generation control.

[0009] One aspect of the present invention is an optical transmission device that includes a control unit that generates a dedicated optical path when it is determined that a dedicated optical path is required to transfer a specific traffic flow among multiple traffic flows held by one or more terminals, based on priority information obtained for each traffic flow that the one or more terminals exchange with a higher-level device.

[0010] One aspect of the present invention is a control device in a signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices that forward signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device and that determines a priority for each traffic flow between the one or more terminals; a higher-level device that communicates with the one or more terminals via the one or more optical transmission devices and the core node; and a control device that controls each device, wherein the control device comprises a control decision unit that performs optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path when it is determined, based on the priority information acquired for each traffic flow, that a dedicated optical path is required for forwarding a specific traffic flow among multiple traffic flows held by the one or more terminals.

[0011] One aspect of the present invention is a signal transfer method in a signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices that transfer signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device and that determines a priority for each traffic flow between the one or more terminals; a higher-level device that communicates with the one or more terminals via the one or more optical transmission devices and the core node; and a control device that controls each device, wherein the signal transfer method acquires priority information for each traffic flow, and when it is determined based on the priority information acquired for each traffic flow that a dedicated optical path is required for transferring a specific traffic flow among a plurality of traffic flows possessed by the one or more terminals, performs optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path, and generates the dedicated optical path in accordance with the optical path generation control.

[0012] The present invention makes it possible to meet delay requirements while reducing delay, even when there is a particular traffic flow that must meet strict delay requirements among multiple traffic flows of one or more wireless terminals.

[0013] FIG. 1 is a diagram illustrating an example of a configuration of a signal transfer system according to a first embodiment. FIG. 2 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the first embodiment. FIG. 3 is a diagram illustrating an example of a configuration of a signal transfer system according to a second embodiment. FIG. 4 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the second embodiment. FIG. 5 is a diagram illustrating an example of a configuration of a signal transfer system according to a third embodiment. FIG. 6 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the third embodiment. FIG. 7 is a diagram illustrating an example of a configuration of a signal transfer system according to a fifth embodiment. FIG. 8 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the fifth embodiment. FIG. 9 is a diagram illustrating an example of a configuration of a signal transfer system according to a sixth embodiment. FIG. 10 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the sixth embodiment. FIG. 11 is a diagram illustrating an example of a configuration of a signal transfer system according to a seventh embodiment. FIG. 12 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the seventh embodiment. FIG. 13 is a diagram illustrating an example of a configuration of a signal transfer system according to an eighth embodiment. FIG. 14 is a flowchart illustrating an example of a processing flow executed by the signal transfer system according to the eighth embodiment. FIG. 15 is a diagram illustrating an example of a configuration of a conventional signal transfer system.

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] First Embodiment Fig. 1 is a diagram illustrating an example of the configuration of a signal transfer system 100 according to a first embodiment. The signal transfer system 100 is a system that transfers signals from one communication device to another communication device. The signal transfer system 100 includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30, a central station 40, a remote station 50, a radio station 60, and an orchestrator 70. Although Fig. 1 illustrates a configuration in which the signal transfer system 100 includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0016] Optical transmission paths connect the server 10 and the optical transmission device 20-1, between the optical transmission device 20-1 and the core node 30, between the core node 30 and the optical transmission device 20-2, between the optical transmission device 20-2 and the central office 40, between the central office 40 and the optical transmission device 20-3, between the optical transmission device 20-3 and the distributed station 50, between the distributed station 50 and the optical transmission device 20-4, and between the optical transmission device 20-4 and the radio station 60. The optical transmission path is a path for transmitting an optical signal, and may be, for example, an optical fiber. The optical transmission path may include an optical amplifier that amplifies the optical signal. The orchestrator 70 is connected to the multiple optical transmission devices 20-1 to 20-4 and to the core node 30 by electric wires or the like.

[0017] The central station 40, the distributed stations 50, and the radio stations 60 are, for example, a CU (Central Unit), a DU (Distributed Unit), and an RU (Radio Unit) in a mobile communication system, respectively. In this case, the network between the server 10 and the core node 30 may be regarded as a data network (DN), the network between the core node 30 and the central station 40 as a mobile backhaul (MBH), the network between the central station 40 and the distributed stations 50 as a mobile midhaul (MMH), and the network between the distributed stations 50 and the radio stations 60 as a mobile fronthaul (MFH).

[0018] The server 10 communicates with one or more wireless terminals 80 wirelessly connected to the wireless station 60. For example, the server 10 receives an uplink signal transmitted from the wireless terminal 80 and transmits a downlink signal to the wireless terminal 80. The server 10 is one aspect of a higher-level device.

[0019] The optical transmission devices 20-1 to 20-4 transfer signals exchanged between the server 10 and one or more wireless terminals 80. The optical transmission device 20-1 transfers signals, for example, between the server 10 and the core node 30. The optical transmission device 20-2 transfers signals, for example, between the core node 30 and the central office 40. The optical transmission device 20-3 transfers signals, for example, between the central office 40 and the remote office 50. The optical transmission device 20-4 transfers signals, for example, between the remote office 50 and the wireless station 60.

[0020] Furthermore, the optical transmission devices 20-1 to 20-4 perform dedicated optical path generation processing in response to instructions from the orchestrator 70. The dedicated optical path generation processing is processing for generating dedicated optical paths in sections where the optical transmission devices 20 are provided. A dedicated optical path is an optical path with a different wavelength from the basic optical path used for transferring normal signals, and is, for example, an optical path set to transmit a specific traffic flow.

[0021] When communication is performed between the server 10 and the wireless terminal 80, the optical transmission devices 20-1 to 20-4 generate an optical path for transferring an optical signal in the section from the server 10 to the wireless station 60. This optical path is a basic optical path used for exchanging all signals transmitted and received by the wireless terminal 80 connected to the wireless station 60 with the server 10. In the basic optical path, multiple traffic flows belonging to one or more wireless terminals 80 connected to the wireless station 60 coexist. In contrast, a dedicated optical path is an optical path set to transmit a specific traffic flow among multiple traffic flows belonging to one or more wireless terminals 80, and therefore, other traffic flows are not mixed in.

[0022] In the example shown in FIG. 1, optical transmission device 20-1 generates a basic optical path and a dedicated optical path between server 10 and core node 30, optical transmission device 20-2 generates a basic optical path and a dedicated optical path between core node 30 and central station 40, optical transmission device 20-3 generates a basic optical path and a dedicated optical path between central station 40 and distributed station 50, and optical transmission device 20-4 generates a basic optical path and a dedicated optical path between distributed station 50 and radio station 60.

[0023] The core node 30 is a base station provided between the optical transmission device 20-1 and the optical transmission device 20-2, and relays signals exchanged between the server 10 and the wireless terminal 80. In the first embodiment, the core node 30 determines the priority of each traffic flow between the wireless terminal 80 and the core node 30 when the wireless terminal 80 starts communication. The exchange for determining the priority of each traffic flow is, for example, a PDU (Packet Data Unit) Session Establishment in a mobile communication system (see, for example, Non-Patent Documents 1 and 2). At this time, the core node 30 extracts priority information indicating the priority of each traffic flow of the wireless terminal 80 and transmits the extracted priority information to the orchestrator 70.

[0024] The priority information is, for example, Network Slice Selection Assistance Information (NSSAI), which is a slice ID determined for each PDU Session ID, or 5G QoS Indicator (5QI), which is determined for each Quality of Service Flow Indicator (QFI) (see, for example, Non-Patent Documents 3 and 4). In this way, in the first embodiment, the core node 30 acquires priority information for each traffic flow of the wireless terminal 80.

[0025] The central office 40 is a base station that is provided between the optical transmission device 20-2 and the optical transmission device 20-3 and that relays signals exchanged between the server 10 and the wireless terminal 80.

[0026] The remote station 50 is a base station provided between the optical transmission device 20-3 and the optical transmission device 20-4, and relays signals exchanged between the server 10 and the wireless terminal 80.

[0027] The wireless station 60 wirelessly communicates with one or more wireless terminals 80. For example, the wireless station 60 transmits signals transferred from the optical transmission device 20-4 to the wireless terminals 80, and transfers signals received from the wireless terminals 80 to the optical transmission device 20-4.

[0028] The orchestrator 70 controls each device (e.g., optical transmission devices 20-1 to 20-4, core node 30, central station 40, remote station 50, and wireless station 60) provided between the server 10 and the wireless terminal 80. The orchestrator 70, for example, acquires priority information for each traffic from the core node 30. Based on the acquired priority information for each traffic, the orchestrator 70 determines whether a dedicated optical path is required for a specific traffic flow of the wireless terminal 80.

[0029] When the orchestrator 70 determines that a dedicated optical path is necessary, it instructs each of the optical transmission devices 20-1 to 20-4 to generate a dedicated optical path. The orchestrator 70, for example, simultaneously performs optical path generation control on each of the optical transmission devices 20-1 to 20-4.

[0030] The wireless terminal 80 is a user terminal operated by a user. The wireless terminal 80 has one or more traffic flows. The wireless terminal 80 communicates wirelessly with the wireless station 60. For example, the wireless terminal 80 receives a downlink signal transmitted from the server 10 via the wireless station 60. For example, the wireless terminal 80 transmits an uplink signal addressed to the server 10 to the wireless station 60.

[0031] The optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the distributed station 50, the radio station 60, and the orchestrator 70 included in the signal transfer system 100 are configured using, for example, a processor such as a central processing unit (CPU), a memory, and a communication interface. Each of the optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the distributed station 50, the radio station 60, and the orchestrator 70 functions as a communication device equipped with a control unit by the processor executing a program.

[0032] The control unit provides functions for causing the communication device to function as each of the optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the distributed station 50, the radio station 60, or the orchestrator 70. Note that all or part of the functions of the control unit may be realized using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA).

[0033] The above program may be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs (Solid State Drives)), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0034] Next, the specific configuration of each device will be described. The core node 30 includes an information acquisition unit 31. The information acquisition unit 31 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. In the following description, as an example, the information acquisition unit 31 acquires priority information for each traffic flow from the wireless terminal 80 to the core node 30. The information acquisition unit 31 notifies the orchestrator 70 of the acquired priority information.

[0035] The optical transmission devices 20-1 to 20-4 include control units 21-1 to 21-4. The control units 21-1 to 21-4 generate basic optical paths in predetermined sections. Furthermore, the control units 21-1 to 21-4 generate dedicated optical paths in predetermined sections in accordance with the optical path generation control of the orchestrator 70. The control unit 21-1 included in the optical transmission device 20-1 generates a dedicated optical path in the section between the server 10 and the core node 30, for example. The control unit 21-2 included in the optical transmission device 20-2 generates a dedicated optical path in the section between the core node 30 and the central office 40, for example. The control unit 21-3 included in the optical transmission device 20-3 generates a dedicated optical path in the section between the central office 40 and the remote station 50, for example. The control unit 21-4 included in the optical transmission device 20-4 generates a dedicated optical path in the section between the remote station 50 and the radio station 60, for example.

[0036] Furthermore, when an optical signal is input after the generation of a dedicated optical path, the control units 21-1 to 21-4 determine whether to output the input optical signal to the basic optical path or the dedicated optical path in accordance with the optical path identifier notified by the orchestrator 70. If the input optical signal matches the optical path identifier, the control units 21-1 to 21-4 output the input optical signal to the dedicated optical path. If the input optical signal does not match the optical path identifier, the control units 21-1 to 21-4 output the input optical signal to the basic optical path.

[0037] In addition, if a network is not configured with the optical transmission devices 20-1 to 20-4 in some sections and low latency is guaranteed by another means, such as priority control in conventional packet transmission, the optical transmission devices 20-1 to 20-4 may not generate dedicated optical paths in those sections and may generate dedicated optical paths only in the other sections. A dedicated optical path may be deleted when the session for the traffic flow is terminated, or it may be retained even if the session is terminated and reused when another traffic flow requires a dedicated optical path.

[0038] The orchestrator 70 includes a control decision unit 71. Based on the priority information received from the core node 30, the control decision unit 71 determines whether a dedicated optical path is required for a specific traffic flow of the wireless terminal 80. Specifically, if a predetermined determination criterion is met based on the priority information, the control decision unit 71 determines that a dedicated optical path is required for the traffic flow from which the priority information was obtained. If the predetermined determination criterion is not met based on the priority information, the control decision unit 71 determines that a dedicated optical path is not required for the traffic flow from which the priority information was obtained.

[0039] The predetermined criterion is, for example, whether a priority ID such as a slice ID or 5QI is a specific numerical value, or whether a dedicated optical path generation request has been notified to the orchestrator 70 as priority information from a device (e.g., core node 30) that has acquired the priority information. If the predetermined criterion is met, the control decision unit 71 performs optical path generation control for the optical transmission devices 20-1 to 20-4 to generate dedicated optical paths. The optical path generation control for dedicated optical paths is control for causing the optical transmission devices 20-1 to 20-4 to generate optical paths for specific traffic flows. Hereinafter, the optical path generation control for dedicated optical paths will also be simply referred to as optical path generation control.

[0040] When performing optical path generation control, the control decision unit 71 notifies the optical transmission devices 20-1 to 20-4 of the optical path identifiers of the dedicated optical paths. The control decision unit 71 also notifies the optical transmission devices 20-1 to 20-4 of the optical path identifiers of the dedicated optical paths for devices connected to the optical transmission device 20 (for example, the server 10, the core node 30, the central station 40, the remote station 50, and the radio station 60). The optical path identifier is, for example, a destination IP address, a VLAN ID, a QFI, a PDU Session ID, etc. There may be multiple routes for generating dedicated optical paths.

[0041] Devices connected to the optical transmission device 20 (e.g., server 10, core node 30, central station 40, distributed station 50, and radio station 60) determine whether to output the input optical signal to the basic optical path or the dedicated optical path according to the optical path identifier notified by the orchestrator 70.

[0042] In the signal transfer system 100 according to the first embodiment, the control decision unit 71 is provided in the control unit of the orchestrator 70 , and the information acquisition unit 31 is provided in the control unit of the core node 30 .

[0043] Fig. 2 is a flowchart showing an example of the flow of processing executed by the signal transfer system 100 in the first embodiment. The signal transfer system 100 repeats the processing shown in Fig. 2. It is assumed that, at the start of the processing in Fig. 2, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60.

[0044] The core node 30 receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S101). The information acquisition unit 31 included in the core node 30 acquires priority information for each traffic flow based on the received signal (step S102). The information acquisition unit 31 transmits the acquired priority information to the orchestrator 70.

[0045] The control decision unit 71 included in the orchestrator 70 acquires the priority information transmitted from the information acquisition unit 31 (step S103). The control decision unit 71 determines whether a dedicated optical path is necessary based on the acquired priority information (step S104). If the control decision unit 71 determines that a dedicated optical path is necessary (step S104—YES), the control decision unit 71 performs optical path generation control for the optical transmission devices 20-1 to 20-4 (step S105). At this time, the control decision unit 71 also notifies the optical transmission device 20 and devices connected to the optical transmission device 20 (e.g., the server 10, the core node 30, the central station 40, the remote station 50, and the radio station 60) of the optical path identifier.

[0046] The control units 21-1 to 21-4 of the optical transmission devices 20-1 to 20-4 generate dedicated optical paths in predetermined sections in accordance with the optical path generation control of the orchestrator 70 (step S106). Thereafter, each device provided between the server 10 and the wireless terminal 80 performs a forwarding process for the input signal (step S107). Specifically, the wireless station 60 converts the signal transmitted from the wireless terminal 80 into an optical signal and outputs it to the optical transmission device 20-4. At this time, the wireless station 60 determines whether to output the optical signal to the basic optical path or the dedicated optical path based on the optical signal and the optical path identifier notified by the orchestrator 70. If the wireless station 60 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the wireless station 60 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0047] The optical transmission device 20-4 receives an optical signal output from the radio station 60 via either the basic optical path or the dedicated optical path. The control unit 21-4 of the optical transmission device 20-4 determines whether to output the received optical signal to the basic optical path or the dedicated optical path, based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the control unit 21-4 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the control unit 21-4 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0048] The distributed station 50 receives an optical signal output from the optical transmission device 20-4 via either the basic optical path or the dedicated optical path. The distributed station 50 determines whether to output the optical signal to the basic optical path or the dedicated optical path based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the distributed station 50 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the distributed station 50 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0049] The optical transmission device 20-3 receives an optical signal output from the remote station 50 via either the basic optical path or the dedicated optical path. The control unit 21-3 of the optical transmission device 20-3 determines whether to output the received optical signal to the basic optical path or the dedicated optical path, based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the control unit 21-3 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the control unit 21-3 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0050] The central office 40 receives an optical signal output from the optical transmission device 20-3 via either the basic optical path or the dedicated optical path. The central office 40 determines whether to output the optical signal to the basic optical path or the dedicated optical path based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the central office 40 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the central office 40 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0051] The optical transmission device 20-2 receives an optical signal output from the central office 40 via either the basic optical path or the dedicated optical path. The control unit 21-2 of the optical transmission device 20-2 determines whether to output the received optical signal to the basic optical path or the dedicated optical path based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the control unit 21-2 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the control unit 21-2 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0052] The core node 30 receives an optical signal output from the optical transmission device 20-2 via either the basic optical path or the dedicated optical path. The core node 30 determines whether to output the optical signal to the basic optical path or the dedicated optical path based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the core node 30 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the core node 30 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0053] The optical transmission device 20-1 receives an optical signal output from the core node 30 via either the basic optical path or the dedicated optical path. The control unit 21-1 of the optical transmission device 20-2 determines whether to output the received optical signal to the basic optical path or the dedicated optical path, based on the received optical signal and the optical path identifier notified by the orchestrator 70. If the control unit 21-1 determines to output the optical signal to the basic optical path, it outputs the optical signal to the basic optical path. On the other hand, if the control unit 21-1 determines to output the optical signal to the dedicated optical path, it outputs the optical signal to the dedicated optical path.

[0054] The server 10 receives an optical signal output from the optical transmission device 20-1 via either the basic optical path or the dedicated optical path. The server 10 performs signal processing on the received optical signal. If necessary, the server 10 transmits a response to the optical signal to the wireless terminal 80. In this way, the signal transfer system 100 can transfer a signal based on a specific traffic flow among multiple traffic flows of one or more wireless terminals 80 via a dedicated optical path.

[0055] If the control determination unit 71 determines in step S104 that a dedicated optical path is not required (step S104-NO), the control determination unit 71 does not perform optical path generation control for the optical transmission devices 20-1 to 20-4. As a result, forwarding processing using the basic optical path is performed in the wired section from the server 10 to the wireless station 60 (step S108).

[0056] According to the signal transfer system 100 configured as described above, when the wireless terminal 80 starts communication, the core node 30 notifies the orchestrator 70 of priority information for each traffic flow determined between the wireless terminal 80 and the core node 30. The orchestrator 70 determines whether a dedicated optical path is necessary for a specific traffic flow based on the priority information for each traffic flow, and simultaneously instructs the optical transmission devices 20-1 to 20-4 to generate dedicated optical paths for the network sections in each of the optical transmission devices 20-1 to 20-4. When each optical transmission device 20 determines that a dedicated optical path is necessary for transferring a specific traffic flow of a specific wireless terminal 80 based on the priority information acquired for each traffic flow, it generates a dedicated optical path in the section between the wireless station 60 and the server 10 and transfers the specific traffic flow of the specific wireless terminal 80 to the server 10 via the generated dedicated optical path.

[0057] With the above configuration, by passing a specific traffic flow that must meet strict delay requirements through a dedicated optical path, it is possible to reduce delays caused by congestion with other traffic, etc. In this way, with this embodiment, it is possible to reduce delays of a specific traffic flow of a specific wireless terminal 80 for which a dedicated optical path has been generated in end-to-end communication from the server 10 to the wireless terminal 80, compared to the conventional technology that uses only basic optical paths.

[0058] (Modification of the First Embodiment) The signal transfer system 100 does not necessarily have to be applied to a mobile communication system, but may be applied to a wireless communication system other than a mobile communication system. In this case, the signal transfer system 100 may not include, for example, the central station 40 and the remote stations 50, and the wireless stations 60 may be regarded as Wi-Fi (registered trademark) access points and the core nodes 30 as Wi-Fi controllers.

[0059] Second Embodiment In a second embodiment, a configuration will be described in which the central office, rather than the core node, notifies the orchestrator of priority information.

[0060] 3 is a diagram illustrating an example of the configuration of a signal transfer system 100a according to the second embodiment. The signal transfer system 100a is a system that transfers signals from one communication device to another. The signal transfer system 100a includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30a, a central station 40a, a remote station 50, a radio station 60, and an orchestrator 70. While FIG. 3 illustrates a configuration in which the signal transfer system 100a includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0061] The signal transfer system 100a is basically the same as the signal transfer system 100, except that the core node 30a corresponding to the core node 30 does not have an information acquisition unit 31, but the central station 40a corresponding to the central station 40 has an information acquisition unit 41, and the orchestrator 70 acquires priority information for each traffic flow from the information acquisition unit 41 of the central station 40a. The following mainly describes the differences from the signal transfer system 100.

[0062] The core node 30a and the central station 40a are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each device in the core node 30a and the central station 40a functions as a communication device equipped with a control unit by the processor executing a program.

[0063] The control units provided in the core node 30a and the central station 40a provide functions for causing the communication device to function as the core node 30a or the central station 40a. All or part of the functions of the control unit may be implemented using hardware such as an ASIC, PLD, or FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0064] The central station 40a includes an information acquisition unit 41. The information acquisition unit 41 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 41 notifies the orchestrator 70 of the acquired priority information.

[0065] In the signal transfer system 100a according to the second embodiment, the information acquisition unit 41 is provided in the control unit of the central office 40a.

[0066] Fig. 4 is a flowchart showing an example of the flow of processing executed by the signal transfer system 100a in the second embodiment. In the signal transfer system 100a, the processing shown in Fig. 4 is repeated. It is assumed that, at the start of the processing in Fig. 4, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60. In Fig. 4, processing that is the same as that in Fig. 2 is assigned the same reference numerals as in Fig. 2, and description thereof will be omitted.

[0067] The central station 40a receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S201). The information acquisition unit 41 included in the central station 40a acquires priority information for each traffic flow based on the received signal (step S202). The information acquisition unit 41 transmits the acquired priority information to the orchestrator 70. Thereafter, the processes from step S103 to step S108 are executed. Note that the core node 30 and the central station 40 in the processes from step S103 to step S108 can be read as the core node 30a and the central station 40a.

[0068] According to the signal transfer system 100a configured as described above, the central office 40a notifies the orchestrator 70 of priority information for each traffic flow. As a result, the signal transfer system 100a can obtain the same effects as those of the first embodiment.

[0069] Third Embodiment In a third embodiment, a configuration will be described in which a distributed station, rather than a core node, notifies an orchestrator of priority information.

[0070] 5 is a diagram illustrating an example of the configuration of a signal transfer system 100b according to the third embodiment. The signal transfer system 100b is a system that transfers signals from one communication device to another communication device. The signal transfer system 100b includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30b, a central station 40, a remote station 50b, a radio station 60, and an orchestrator 70. While FIG. 5 illustrates a configuration in which the signal transfer system 100b includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0071] The signal transfer system 100b is basically the same as the signal transfer system 100, except that the core node 30b corresponding to the core node 30 does not have an information acquisition unit 31, the distributed station 50b corresponding to the distributed station 50 has an information acquisition unit 51, and the orchestrator 70 acquires priority information for each traffic flow from the information acquisition unit 51 of the distributed station 50b. The following mainly describes the differences from the signal transfer system 100.

[0072] The core node 30b and the distributed station 50b are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each device of the core node 30b and the distributed station 50b functions as a communication device equipped with a control unit by the processor executing a program.

[0073] The control units included in the core node 30b and the distributed station 50b provide functions for causing the communication device to function as the core node 30b or the distributed station 50b. All or part of the functions of the control unit may be implemented using hardware such as an ASIC, PLD, or FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0074] The remote station 50b includes an information acquisition unit 51. The information acquisition unit 51 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 51 notifies the orchestrator 70 of the acquired priority information.

[0075] In the signal transfer system 100b according to the third embodiment, the information acquisition unit 51 is provided in the control unit of the remote station 50b.

[0076] Fig. 6 is a flowchart showing an example of the flow of processing executed by the signal transfer system 100b in the third embodiment. In the signal transfer system 100b, the processing shown in Fig. 6 is repeated. It is assumed that, at the start of the processing in Fig. 6, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60. In Fig. 6, processing that is the same as that in Fig. 2 is assigned the same reference numerals as in Fig. 2, and description thereof will be omitted.

[0077] The remote station 50b receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S301). The information acquisition unit 51 included in the remote station 50b acquires priority information for each traffic flow based on the received signal (step S302). The information acquisition unit 51 transmits the acquired priority information to the orchestrator 70. Thereafter, the processes from step S103 to step S108 are executed. Note that the core node 30 and the remote station 50 in the processes from step S103 to step S108 can be read as the core node 30b and the remote station 50b.

[0078] According to the signal transfer system 100b configured as described above, the remote station 50b notifies the orchestrator 70 of priority information for each traffic flow. As a result, the signal transfer system 100b can obtain the same effects as those of the first embodiment.

[0079] Fourth Embodiment In a fourth embodiment, a configuration will be described in which a radio station, rather than a core node, notifies an orchestrator of priority information.

[0080] 7 is a diagram illustrating an example of the configuration of a signal transfer system 100c according to the fourth embodiment. The signal transfer system 100c is a system that transfers signals from one communication device to another communication device. The signal transfer system 100c includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30c, a central station 40, a remote station 50, a radio station 60c, and an orchestrator 70. While FIG. 7 illustrates a configuration in which the signal transfer system 100c includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0081] The signal transfer system 100c is basically the same as the signal transfer system 100, except that the core node 30c corresponding to the core node 30 does not have the information acquisition unit 31, and the radio station 60c corresponding to the radio station 60 has the information acquisition unit 61, and the orchestrator 70 acquires priority information for each traffic flow from the information acquisition unit 61 of the radio station 60c. The following mainly describes the differences from the signal transfer system 100.

[0082] The core node 30c and the wireless station 60c are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each of the core node 30c and the wireless station 60c functions as a communication device equipped with a control unit by the processor executing a program.

[0083] The control units included in the core node 30c and the radio station 60c provide the functions for causing the communication device to function as the core node 30c or the radio station 60c. Note that all or part of the functions of the control unit may be realized using hardware such as an ASIC, a PLD, or an FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, and a semiconductor storage device (e.g., an SSD), as well as storage devices such as a hard disk or semiconductor storage device built into a computer system. The above program may be transmitted via a telecommunications line.

[0084] The wireless station 60c includes an information acquisition unit 61. The information acquisition unit 61 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 61 notifies the orchestrator 70 of the acquired priority information.

[0085] In the signal transfer system 100c according to the fourth embodiment, the information acquisition unit 61 is provided in the control unit of the wireless station 60c.

[0086] Fig. 8 is a flowchart showing an example of the flow of processing executed by the signal transfer system 100c in the fourth embodiment. In the signal transfer system 100c, the processing shown in Fig. 8 is repeated. It is assumed that, at the start of the processing in Fig. 8, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60c. In Fig. 8, processing that is the same as that in Fig. 2 is assigned the same reference numerals as in Fig. 2, and description thereof will be omitted.

[0087] The wireless station 60c receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S401). The information acquisition unit 61 included in the wireless station 60c acquires priority information for each traffic flow based on the received signal (step S402). The information acquisition unit 61 transmits the acquired priority information to the orchestrator 70. Thereafter, the processes from step S103 to step S108 are executed. Note that the core node 30 and the wireless station 60 in the processes from step S103 to step S108 can be read as the core node 30c and the wireless station 60.

[0088] According to the signal transfer system 100c configured as above, the radio station 60c notifies the orchestrator 70 of priority information for each traffic flow. As a result, the signal transfer system 100c can obtain the same effects as those of the first embodiment.

[0089] (Variation of the Fourth Embodiment) The signal transfer system 100c does not necessarily need to be applied to a mobile communication system, and may be applied to a wireless communication system other than a mobile communication system. In this case, the signal transfer system 100c may not include, for example, the central station 40 and the remote station 50, and the wireless station 60c may be regarded as a Wi-Fi (registered trademark) access point, and the core node 30 may be regarded as a Wi-Fi controller.

[0090] Fifth Embodiment In a fifth embodiment, a configuration will be described in which a core node includes an information acquisition unit, an orchestrator is divided into a base station controller and an optical transmission equipment controller, and the two controllers cooperate to perform control.

[0091] 9 is a diagram illustrating an example of the configuration of a signal transfer system 200 according to the fifth embodiment. The signal transfer system 200 is a system that transfers signals from one communication device to another communication device. The signal transfer system 200 includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30, a central station 40, a remote station 50, a radio station 60, a base station controller 85, and an optical transmission device controller 90. While FIG. 9 illustrates a configuration in which the signal transfer system 200 includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0092] The signal transfer system 200 is basically the same as the signal transfer system 100 except that it does not include the orchestrator 70, but includes a base station controller 85 and an optical transmission equipment controller 90. The following description will focus on the differences from the signal transfer system 100.

[0093] The base station controller 85 acquires priority information for each traffic flow from the core node 30. Based on the acquired priority information for each traffic flow, the base station controller 85 determines whether a dedicated optical path is necessary for a specific traffic flow of the wireless terminal 80. If the base station controller 85 determines that a dedicated optical path is necessary, it instructs the optical transmission equipment controller 90 to generate a dedicated optical path.

[0094] The optical transmission equipment controller 90 controls each device (e.g., optical transmission equipment 20-1 to 20-4, core node 30, central station 40, remote station 50, and radio station 60) provided between the server 10 and the radio terminal 80. In response to a dedicated optical path generation instruction from the base station controller 85, the optical transmission equipment controller 90 simultaneously performs optical path generation control for each of the optical transmission equipment 20-1 to 20-4.

[0095] As described above, in the fifth embodiment, the optical transmission device controller 90 simultaneously performs optical path generation control for each of the optical transmission devices 20-1 to 20-4, and therefore each of the optical transmission devices 20-1 to 20-4 performs dedicated optical path generation processing in response to instructions from the optical transmission device controller 90.

[0096] The optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the distributed station 50, the radio station 60, the base station controller 85, and the optical transmission device controller 90 included in the signal transfer system 200 are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each of the optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the distributed station 50, the radio station 60, the base station controller 85, and the optical transmission device controller 90 functions as a communication device equipped with a control unit by the processor executing a program.

[0097] The control unit provides each function for causing the communication device to function as the optical transmission devices 20-1 to 20-4, the core node 30, the central station 40, the remote station 50, the radio station 60, the base station controller 85, or the optical transmission device controller 90. Note that all or part of the functions of the control unit may be realized using hardware such as an ASIC, a PLD, or an FPGA.

[0098] The above program may be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs (Solid State Drives)), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0099] Next, the specific configuration of each device will be described. The base station controller 85 includes an information analyzer 86. The information analyzer 86 acquires priority information acquired by the information acquirer 31 of the core node 30. The information analyzer 86 determines whether a dedicated optical path is required for a specific traffic flow of the wireless terminal 80 based on the acquired priority information. Specifically, if a predetermined criterion is met based on the priority information, the information analyzer 86 determines that a dedicated optical path is required for the traffic flow from which the priority information was acquired. If the predetermined criterion is not met based on the priority information, the information analyzer 86 determines that a dedicated optical path is not required for the traffic flow from which the priority information was acquired.

[0100] If a predetermined criterion is met, the information analysis unit 86 transmits an optical path generation instruction to the optical transmission equipment controller 90. The optical path generation instruction is a control signal for notifying that a dedicated optical path needs to be generated. When transmitting the optical path generation instruction, the information analysis unit 86 notifies the optical transmission equipment controller 90 of the optical path identifier of the dedicated optical path.

[0101] The optical transmission device controller 90 includes a control decision unit 91. Upon receiving an optical path generation instruction from the base station controller 85, the control decision unit 91 performs optical path generation control of dedicated optical paths for the optical transmission devices 20-1 to 20-4. When performing optical path generation control, the control decision unit 91 notifies the optical transmission devices 20-1 to 20-4 of optical path identifiers of the dedicated optical paths. The control decision unit 91 also notifies the optical transmission devices 20-1 to 20-4 of optical path identifiers of the dedicated optical paths for devices connected to the optical transmission device 20 (e.g., the server 10, the core node 30, the central station 40, the remote station 50, and the radio station 60).

[0102] Devices connected to the optical transmission device 20 (e.g., server 10, core node 30, central station 40, distributed station 50, and radio station 60) determine whether to output the input optical signal to the basic optical path or the dedicated optical path according to the optical path identifier notified by the optical transmission device controller 90.

[0103] In the signal transfer system 200 of the fifth embodiment, the information acquisition unit 31 is provided in the control unit of the core node 30, the information analysis unit 86 is provided in the control unit of the base station controller 85, and the control decision unit 91 is provided in the control unit of the optical transmission device controller 90.

[0104] Fig. 10 is a flowchart showing an example of the flow of processing executed by the signal transfer system 200 in the fifth embodiment. The signal transfer system 200 repeats the processing shown in Fig. 10. It is assumed that, at the start of the processing in Fig. 10, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60.

[0105] The core node 30 receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S501). The information acquisition unit 31 included in the core node 30 acquires priority information for each traffic flow based on the received signal (step S502). The information acquisition unit 31 transmits the acquired priority information to the base station controller 85.

[0106] The information analysis unit 86 included in the base station controller 85 acquires the priority information transmitted from the information acquisition unit 31 (step S503). The information analysis unit 86 determines whether a dedicated optical path is necessary based on the acquired priority information (step S504). If the information analysis unit 86 determines that a dedicated optical path is necessary (step S504—YES), the information analysis unit 86 transmits an optical path creation instruction to the optical transmission equipment controller 90 (step S505).

[0107] The control decision unit 91 included in the optical transmission device controller 90 acquires the optical path creation instruction transmitted from the base station controller 85. Based on the acquired optical path creation instruction, the control decision unit 91 performs optical path creation control for the optical transmission devices 20-1 to 20-4 (step S506). At this time, the control decision unit 91 also notifies the devices connected to the optical transmission device 20 (for example, the server 10, the core node 30, the central station 40, the remote station 50, and the radio station 60) of the optical path identifier.

[0108] The control units 21-1 to 21-4 of the optical transmission devices 20-1 to 20-4 generate dedicated optical paths in predetermined sections in accordance with the optical path generation control of the optical transmission device controller 90 (step S507). Thereafter, each device provided between the server 10 and the wireless terminal 80 performs a forwarding process for the input signal (step S508). The forwarding process in step S508 is the same as step S107 in the first embodiment, except that each device provided between the server 10 and the wireless terminal 80 determines whether to output the optical signal to the basic optical path or the dedicated optical path based on the optical path identifier notified by the optical transmission device controller 90, and therefore a description thereof will be omitted.

[0109] If the control determination unit 91 determines in step S504 that a dedicated optical path is not required (step S504-NO), the control determination unit 91 does not perform optical path generation control for the optical transmission devices 20-1 to 20-4. As a result, forwarding processing using the basic optical path is executed in the wired section from the server 10 to the wireless station 60 (step S509).

[0110] According to the signal transfer system 200 configured as described above, when the wireless terminal 80 starts communication, the core node 30 notifies the base station controller 85 of priority information for each traffic flow determined between the wireless terminal 80 and the core node 30. The base station controller 85 determines whether a dedicated optical path is necessary for a specific traffic flow based on the priority information for each traffic flow, and if a specific traffic flow requires a dedicated optical path, instructs the optical transmission equipment controller 90 to generate a dedicated optical path. In response to the instruction from the base station controller 85, the optical transmission equipment controller 90 simultaneously instructs the optical transmission devices 20-1 to 20-4 to generate dedicated optical paths for the network sections in each of the optical transmission devices 20-1 to 20-4. When each optical transmission device 20 determines that a dedicated optical path is necessary for transferring a specific traffic flow of a specific wireless terminal 80 based on the priority information acquired for each traffic flow, it generates a dedicated optical path in the section between the wireless station 60 and the server 10 and transfers the specific traffic flow of the specific wireless terminal 80 to the server 10 via the generated dedicated optical path.

[0111] With the above configuration, by passing a specific traffic flow that must meet strict delay requirements through a dedicated optical path, it is possible to reduce delays caused by congestion with other traffic, etc. In this way, with this embodiment, it is possible to reduce delays of a specific traffic flow of a specific wireless terminal 80 for which a dedicated optical path has been generated in end-to-end communication from the server 10 to the wireless terminal 80, compared to the conventional technology that uses only basic optical paths.

[0112] (Variation of the Fifth Embodiment) The signal forwarding system 200 does not necessarily have to be applied to a mobile communication system, and may be applied to a wireless communication system other than a mobile communication system. In this case, the signal forwarding system 200 may not include, for example, the central station 40 and the remote stations 50, and the wireless stations 60 may be regarded as Wi-Fi (registered trademark) access points and the core nodes 30 as Wi-Fi controllers.

[0113] Sixth Embodiment In a sixth embodiment, a configuration will be described in which the central office, rather than the core node, notifies the base station controller of priority information.

[0114] FIG. 11 is a diagram illustrating an example of the configuration of a signal transfer system 200a according to the sixth embodiment. The signal transfer system 200a is a system that transfers signals from one communication device to another. The signal transfer system 200a includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30a, a central station 40a, a remote station 50, a radio station 60, a base station controller 85, and an optical transmission device controller 90. While FIG. 11 illustrates a configuration in which the signal transfer system 200a includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0115] The signal transfer system 200a is basically the same as the signal transfer system 200, except that the core node 30a corresponding to the core node 30 does not have an information acquisition unit 31, but the central station 40a corresponding to the central station 40 has an information acquisition unit 41, and the base station controller 85 acquires priority information for each traffic flow from the information acquisition unit 41 of the central station 40a. The following mainly describes the differences from the signal transfer system 200.

[0116] The core node 30a and the central station 40a are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each device in the core node 30a and the central station 40a functions as a communication device equipped with a control unit by the processor executing a program.

[0117] The control units provided in the core node 30a and the central station 40a provide functions for causing the communication device to function as the core node 30a or the central station 40a. All or part of the functions of the control unit may be implemented using hardware such as an ASIC, PLD, or FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0118] The central station 40a includes an information acquisition unit 41. The information acquisition unit 41 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 41 notifies the base station controller 85 of the acquired priority information.

[0119] In the signal transfer system 200a according to the sixth embodiment, the information acquisition unit 41 is provided in the control unit of the central office 40a.

[0120] Fig. 12 is a flowchart showing an example of the flow of processing executed by the signal transfer system 200a in the sixth embodiment. In the signal transfer system 200a, the processing shown in Fig. 12 is repeated. It is assumed that, at the start of the processing in Fig. 12, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60. In Fig. 12, processing that is the same as that in Fig. 10 is assigned the same reference numerals as in Fig. 10, and description thereof will be omitted.

[0121] The central station 40a receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S601). The information acquisition unit 41 included in the central station 40a acquires priority information for each traffic flow based on the received signal (step S602). The information acquisition unit 41 transmits the acquired priority information to the base station controller 85. Thereafter, the processes from step S503 to step S509 are executed. Note that the core node 30 and the central station 40 in the processes from step S503 to step S509 can be read as the core node 30a and the central station 40a.

[0122] According to the signal transfer system 200a configured as described above, the central office 40a notifies the base station controller 85 of priority information for each traffic flow. As a result, the signal transfer system 200a can obtain the same effects as those of the fifth embodiment.

[0123] Seventh Embodiment In the seventh embodiment, a configuration will be described in which the remote station, rather than the core node, notifies the base station controller of priority information.

[0124] FIG. 13 is a diagram illustrating an example of the configuration of a signal transfer system 200b according to the seventh embodiment. The signal transfer system 200b is a system that transfers signals from one communication device to another. The signal transfer system 200b includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30b, a central office 40, a remote office 50b, a radio station 60, a base station controller 85, and an optical transmission device controller 90. While FIG. 13 illustrates a configuration in which the signal transfer system 200b includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0125] The signal transfer system 200b is basically the same as the signal transfer system 200, except that the core node 30b corresponding to the core node 30 does not have an information acquisition unit 31, the remote station 50b corresponding to the remote station 50 has an information acquisition unit 51, and the base station controller 85 acquires priority information for each traffic flow from the information acquisition unit 51 of the remote station 50b. The following mainly describes the differences from the signal transfer system 200.

[0126] The core node 30b and the distributed station 50b are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each device of the core node 30b and the distributed station 50b functions as a communication device equipped with a control unit by the processor executing a program.

[0127] The control units included in the core node 30b and the distributed station 50b provide functions for causing the communication device to function as the core node 30b or the distributed station 50b. All or part of the functions of the control unit may be implemented using hardware such as an ASIC, PLD, or FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and semiconductor storage devices (e.g., SSDs), as well as storage devices such as hard disks and semiconductor storage devices built into computer systems. The above program may be transmitted via a telecommunications line.

[0128] The remote station 50b includes an information acquisition unit 51. The information acquisition unit 51 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 51 notifies the base station controller 85 of the acquired priority information.

[0129] In a signal transfer system 200b according to the seventh embodiment, the information acquisition unit 51 is provided in the control unit of the remote station 50b.

[0130] Fig. 14 is a flowchart showing an example of the flow of processing executed by the signal transfer system 200b in the seventh embodiment. In the signal transfer system 200b, the processing shown in Fig. 14 is repeated. It is assumed that, at the start of the processing in Fig. 6, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60. In Fig. 14, processing similar to that in Fig. 10 is assigned the same reference numerals as in Fig. 10, and description thereof will be omitted.

[0131] The remote station 50b receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S701). The information acquisition unit 51 included in the remote station 50b acquires priority information for each traffic flow based on the received signal (step S702). The information acquisition unit 51 transmits the acquired priority information to the base station controller 85. Thereafter, the processes from step S503 to step S509 are executed. Note that the core node 30 and the remote station 50 in the processes from step S503 to step S509 can be read as the core node 30b and the remote station 50b.

[0132] According to the signal transfer system 200b configured as above, the remote station 50b notifies the base station controller 85 of priority information for each traffic flow. As a result, the signal transfer system 200b can obtain the same effects as those of the fifth embodiment.

[0133] Eighth Embodiment In an eighth embodiment, a configuration will be described in which a wireless station, rather than a core node, notifies a base station controller of priority information.

[0134] FIG. 15 is a diagram illustrating an example configuration of a signal transfer system 200c according to the eighth embodiment. The signal transfer system 200c is a system that transfers signals from one communication device to another. The signal transfer system 200c includes, for example, a server 10, multiple optical transmission devices 20-1 to 20-4, a core node 30c, a central office 40, a remote office 50, a radio station 60c, a base station controller 85, and an optical transmission device controller 90. While FIG. 15 illustrates a configuration in which the signal transfer system 200c includes four optical transmission devices 20, the number of optical transmission devices 20 is not limited as long as there is more than one.

[0135] The signal transfer system 200c is basically the same as the signal transfer system 200, except that the core node 30c corresponding to the core node 30 does not have the information acquisition unit 31, and the radio station 60c corresponding to the radio station 60 has the information acquisition unit 61, and the base station controller 85 acquires priority information for each traffic flow from the information acquisition unit 61 of the radio station 60c. The following mainly describes the differences from the signal transfer system 200.

[0136] The core node 30c and the wireless station 60c are configured using, for example, a processor such as a CPU, a memory, and a communication interface. Each of the core node 30c and the wireless station 60c functions as a communication device equipped with a control unit by the processor executing a program.

[0137] The control units included in the core node 30c and the radio station 60c provide the functions for causing the communication device to function as the core node 30c or the radio station 60c. Note that all or part of the functions of the control unit may be realized using hardware such as an ASIC, a PLD, or an FPGA. The above program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, and a semiconductor storage device (e.g., an SSD), as well as storage devices such as a hard disk or semiconductor storage device built into a computer system. The above program may be transmitted via a telecommunications line.

[0138] The wireless station 60c includes an information acquisition unit 61. The information acquisition unit 61 acquires priority information for each traffic flow exchanged between the wireless terminal 80 and the core node 30. The information acquisition unit 61 notifies the base station controller 85 of the acquired priority information.

[0139] In a signal transfer system 200c according to the eighth embodiment, an information acquisition unit 61 is provided in a control unit of a wireless station 60c.

[0140] Fig. 16 is a flowchart showing an example of the flow of processing executed by the signal transfer system 200c in the eighth embodiment. In the signal transfer system 200c, the processing shown in Fig. 16 is repeated. It is assumed that, at the start of the processing in Fig. 16, a basic optical path has been generated in the wired section from the server 10 to the wireless station 60c. In Fig. 16, processing that is the same as that in Fig. 10 is assigned the same reference numerals as in Fig. 10, and description thereof will be omitted.

[0141] The wireless station 60c receives a signal for each traffic flow when the wireless terminal 80 starts communication (step S801). The information acquisition unit 61 included in the wireless station 60c acquires priority information for each traffic flow based on the received signal (step S802). The information acquisition unit 61 transmits the acquired priority information to the base station controller 85. Thereafter, the processes from step S503 to step S509 are executed. Note that the core node 30 and the wireless station 60 in the processes from step S503 to step S509 can be read as the core node 30c and the wireless station 60.

[0142] According to the signal transfer system 200c configured as above, the wireless station 60c notifies the base station controller 85 of priority information for each traffic flow. As a result, the signal transfer system 200c can obtain the same effects as those of the fifth embodiment.

[0143] (Variation of the Eighth Embodiment) The signal transfer system 200c does not necessarily need to be applied to a mobile communication system, and may be applied to a wireless communication system other than a mobile communication system. In this case, the signal transfer system 200c may not include, for example, the central station 40 and the remote station 50, and the wireless station 60c may be regarded as a Wi-Fi (registered trademark) access point, and the core node 30 may be regarded as a Wi-Fi controller.

[0144] (Variation 1 common to the first to eighth embodiments) In each of the above-described embodiments, a signal transfer system that includes a wireless terminal and a wireless station and performs wireless communication has been described as an example, but the signal transfer system in each embodiment may also be configured to include a terminal device and a terminal accommodating station and perform wired communication. The terminal device communicates with the terminal accommodating station via a wired connection. Like a wireless terminal, the terminal device has one or more traffic flows. The terminal accommodating station is a base station that accommodates the terminal device.

[0145] (Variation 2 common to the first to eighth embodiments) In the above-described embodiments, the processing during upstream communication has been described as an example. For example, the processing based on a traffic flow from the wireless terminal 80 to the server 10, which is a higher-level device, has been described as an example. In contrast, the above-described embodiments can also be applied to processing during downstream communication. For example, the processing can be similarly applied to processing based on a traffic flow from the server 10, which is a higher-level device, to the wireless terminal 80. Except for the fact that the source of the traffic flow is different, the specific processing is the same as in the above-described embodiments.

[0146] Although an embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs within the scope of the gist of the present invention.

[0147] The present invention can be applied to a communication system that accommodates wireless terminals and a communication control method.

[0148] 10...server, 20, 20-1 to 20-4...optical transmission device, 21, 21-1 to 21-4...control unit, 30, 30a, 30b, 30c...core node, 31, 41, 51, 61...information acquisition unit, 40, 40a...central station, 50, 50b...remote station, 60, 60c...radio station, 70...orchestrator, 71, 91...control decision unit, 80...radio terminal, 85...base station controller, 86...information analysis unit, 90...optical transmission device controller, 100, 100a, 100b, 100c, 100d, 200, 200a, 200b, 200c, 200d...signal transfer system

Claims

1. A signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices for transferring signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device and for determining a priority for each traffic flow between the one or more terminals; a higher-level device for communicating with the one or more terminals via the one or more optical transmission devices and the core node; and a control device for controlling each device, wherein the signal transfer system comprises: an information acquisition unit for acquiring priority information for each traffic flow; a control decision unit for performing optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path when it is determined that a dedicated optical path is necessary for transferring a specific traffic flow among a plurality of traffic flows possessed by the one or more terminals based on the priority information acquired for each traffic flow; and a control unit for generating the dedicated optical path in accordance with the optical path generation control.

2. The signal transfer system according to claim 1, wherein the control device comprises the control decision unit, the core node or the terminal accommodating station comprises the information acquisition unit, and the information acquisition unit notifies the acquired information on priority for each traffic flow.

3. The signal transfer system of claim 1, further comprising a distributed station and a central station which relay signals exchanged between the one or more terminals and a higher-level device between the terminal accommodating station and the core node, the control device comprising the control decision unit, the distributed station or the central station comprising the information acquisition unit, and the information acquisition unit notifying the control device of the acquired priority information for each traffic flow.

4. A signal transfer system as described in any one of claims 1 to 3, further comprising an information analysis unit that determines whether a dedicated optical path is necessary for transferring a specific traffic flow among multiple traffic flows held by the one or more terminals based on the priority information obtained for each of the traffic flows, and when the information analysis unit determines that the dedicated optical path is necessary, the control decision unit performs optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path.

5. The signal transfer system according to any one of claims 1 to 3, wherein the one or more optical transmission devices are a plurality of optical transmission devices, and the control decision unit performs the optical path generation control for each of the plurality of optical transmission devices at the same timing.

6. An optical transmission device comprising: a control unit that generates a dedicated optical path when it is determined that a dedicated optical path is necessary for transferring a specific traffic flow among multiple traffic flows held by one or more terminals based on priority information obtained for each traffic flow exchanged between the one or more terminals and a higher-level device.

7. A control device in a signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices for transferring signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device for determining a priority for each traffic flow between the one or more terminals; a higher-level device for communicating with the one or more terminals via the one or more optical transmission devices and the core node; and a control device for controlling each device, the control device comprising: a control decision unit that performs optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path when it is determined that a dedicated optical path is necessary for transferring a specific traffic flow among multiple traffic flows held by the one or more terminals based on the priority information acquired for each traffic flow.

8. A signal transfer method in a signal transfer system comprising: a terminal accommodating station accommodating one or more terminals; one or more optical transmission devices for transferring signals exchanged between the one or more terminals and a higher-level device; a core node provided between the one or more optical transmission devices and the higher-level device for determining a priority for each traffic flow between the one or more terminals; a higher-level device for communicating with the one or more terminals via the one or more optical transmission devices and the core node; and a control device for controlling each device, the signal transfer method comprising: acquiring priority information for each traffic flow; and when it is determined based on the priority information acquired for each traffic flow that a dedicated optical path is necessary for transferring a specific traffic flow among a plurality of traffic flows possessed by the one or more terminals, performing optical path generation control to instruct each of the one or more optical transmission devices to generate the dedicated optical path; and generating the dedicated optical path in accordance with the optical path generation control.

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