Signal transfer system, signal transfer control device, signal transfer control method, and program

Abstract

This signal transfer system comprises a first signal transfer control device associated with a first network and a second signal transfer control device associated with a second network connected to the first network via an intermediate node. The first signal transfer control device includes: a first communication unit that transmits first schedule information at a prescribed notification period; and a second communication unit that transmits a trigger signal on the basis of a change in the volume of traffic on the first network. The second signal transfer control device includes: an acquisition unit that acquires the first schedule information at the prescribed notification period; a third communication unit that acquires the trigger signal; a change volume determination unit that, if the trigger signal is acquired, determines whether or not the volume of change in the traffic on the first network is a threshold value or greater, on the basis of the first schedule information; an information updating unit that updates the second schedule information if the volume of change was determined to be the threshold value or greater; and a period specification unit that specifies the prescribed notification period if the volume of change was determined to be the threshold value or greater.

Description

Technical Field

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

Background Art

[0002] In 5G (the fifth-generation mobile communication system) and the like, a signal transfer system including MFH (Mobile Fronthaul), MMH (Mobile Midhaul), and MBH (Mobile Backhaul) and configured to control traffic is known.

[0003] For example, there is a signal transfer system in which a communication path between a plurality of DUs (Distributed units) each connected to a plurality of RUs (Radio units) and a plurality of CUs (Central units) is switched by an SW (Switch).

[0004] Also, in a signal transfer system that sequentially transfers signals, generally, packets are delayed when passing through a switch. Therefore, various technologies are applied to realize a low-latency network.

[0005] For example, as one of the technologies for reducing the delay of high-priority signals, the TAS (Time Aware Shaper) technology is known. In TAS, complete priority control is performed, and for signals of a priority level that are the target of priority control and are transmitted periodically, transmission time slots are reserved (the gate is opened and the gates of other priority levels are closed) in the signal transfer device. In the priority transmission period, signals of other priority levels cannot be transmitted (are waited for). Also, in complete priority control, after the signal transfer device receives a signal that is the target of priority control and the signal becomes transmissible, when the transmission of the currently transmitted signal ends, the corresponding time gate is opened (see Patent Document 1).

[0006] In addition, Non-Patent Document 1 defines bridges and LANs for networks that require low latency.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Non-Patent Documents

[0008]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] However, conventionally, for example, when transferring a signal from a network that transfers a signal by TAS to another network that transfers a signal by another TAS via an intermediate node, it has not been possible to synchronize scheduling information. Also, in such a network, the delay time at the intermediate node has not been considered.

[0010] For example, when reserving a time slot, it has been necessary to include a certain fixed time when setting the processing time at the intermediate node. This fixed time is an estimated value. Therefore, in order to have traffic arrive within the time slot, it has been necessary to add a margin to the reserved time, which may reduce the bandwidth utilization efficiency.

[0011] The present invention has been made in view of the above-described problems, and an object thereof is to provide a signal transfer system, a signal transfer control device, a signal transfer control method, and a program that can improve the bandwidth utilization efficiency even when transferring signals across a plurality of different networks for transferring signals.

Means for Solving the Problems

[0012] One aspect of the present invention is a signal transfer system including a first signal transfer control device associated with a first network and a second signal transfer control device associated with a second network connected to the first network via an intermediate node, wherein the first signal transfer control device includes a first communication unit that transmits first schedule information indicating a schedule for signal transfer in the first network at a predetermined notification period, and a second communication unit that transmits a trigger signal based on a change amount of traffic in the first network; the second signal transfer control device includes an acquisition unit that acquires the first schedule information at the predetermined notification period, a third communication unit that acquires the trigger signal from the second communication unit, a change amount determination unit that determines whether or not the change amount of traffic in the first network is equal to or greater than a threshold value based on the first schedule information when the trigger signal is acquired, an information update unit that updates second schedule information indicating a schedule for signal transfer in the second network when it is determined that the change amount is equal to or greater than the threshold value, and a period instruction unit that instructs the first signal transfer control device of the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value.

[0013] One aspect of the present invention is an acquisition unit that acquires, from another signal transfer control device associated with the first network, first schedule information indicating a schedule for signal transfer in the first network at a predetermined notification period, a communication unit that acquires a trigger signal based on a change amount of traffic in the first network from the other signal transfer control device, a change amount determination unit that determines, based on the first schedule information, whether or not the change amount of traffic in the first network is equal to or greater than a threshold value when the trigger signal is acquired, an information update unit that updates second schedule information indicating a schedule for signal transfer in a second network connected to the first network via an intermediate node when it is determined that the change amount is equal to or greater than the threshold value, and a period instruction unit that instructs the other signal transfer control device of the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value, which is a signal transfer control device.

[0014] One aspect of the present invention is a signal transfer control method executed by a signal transfer control device, which includes an acquisition step of acquiring, from another signal transfer control device associated with the first network, first schedule information indicating a schedule for signal transfer in the first network at a predetermined notification period, a communication step of acquiring a trigger signal based on a change amount of traffic in the first network from the other signal transfer control device, a change amount determination step of determining, based on the first schedule information, whether or not the change amount of traffic in the first network is equal to or greater than a threshold value when the trigger signal is acquired, an information update step of updating second schedule information indicating a schedule for signal transfer in a second network connected to the first network via an intermediate node when it is determined that the change amount is equal to or greater than the threshold value, and a period instruction step of instructing the other signal transfer control device of the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value, which is a signal transfer control method.

[0015] One aspect of the present invention is a program for causing a computer to function as the above signal transfer control device.

Advantages of the Invention

[0016] According to the present invention, even when transferring a signal across a plurality of different networks for transferring the signal, the bandwidth utilization efficiency can be improved.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Modes for Carrying Out the Invention

[0018] First, a signal transfer system of a comparative example with the signal transfer systems of each embodiment will be described. FIG. 9 is a diagram showing a configuration example of the signal transfer system 1 of the comparative example. In the signal transfer system 1, for example, a first network 2 and a second network 3 are connected via a central office 4. Then, the signal transfer system 1 transfers signals (traffic) so that the distributed stations (lower devices) 10-1 and 10-2 communicate bidirectionally with the upper device 12 via the first network 2, the central office 4, and the second network 3. The distributed stations 10-1 and 10-2 (or the upper device 12) are devices that generate traffic.

[0019] The first network 2 includes, for example, signal transfer devices 5-1 to 5-4 and a signal transfer control device 6-1. The signal transfer devices 5-1 to 5-4 constitute a plurality of paths for transferring signals between the distributed stations 10-1 and 10-2 and the central office 4.

[0020] Then, the signal transfer devices 5-1 to 5-4 transfer the signals transmitted by the distributed stations 10-1 and 10-2 to the central office 4 by TAS according to the control of the signal transfer control device 6-1. Also, the signal transfer devices 5-1 to 5-4 transfer the signals transmitted by the central office 4 to the distributed stations 10-1 and 10-2 by TAS according to the control of the signal transfer control device 6-1.

[0021] The signal transfer control device 6-1 determines a path for transferring signals between the distributed stations 10-1 and 10-2 and the central office 4, outputs an instruction so that the signals are transferred through the determined path, and controls the signal transfer devices 5-1 to 5-4.

[0022] The second network 3 includes, for example, signal transfer devices 5-5 to 5-8 and a signal transfer control device 6-2. The signal transfer devices 5-5 to 5-8 constitute a plurality of paths for transferring signals between the central office 4 and the upper device 12.

[0023] Then, the signal transfer devices 5-5 to 5-8 transfer the signals transmitted by the central office 4 to the upper device 12 by TAS according to the control of the signal transfer control device 6-2. Also, the signal transfer devices 5-5 to 5-8 transfer the signals transmitted by the upper device 12 to the central office 4 by TAS according to the control of the signal transfer control device 6-2.

[0024] The signal transfer control device 6-2 determines a path for transferring signals between the central office 4 and the upper device 12, outputs an instruction so that the signals are transferred through the determined path, and controls the signal transfer devices 5-5 to 5-8.

[0025] The central office 4 is, for example, a CU (Central unit: centralized base station), and is an intermediate node that transfers signals from the first network 2 to the second network 3 or from the second network 3 to the first network 2. That is, the central office 4 aggregates the upstream signals transferred via the first network 2 and transfers them to the second network 3, and distributes and transfers the downstream signals transferred via the second network 3 to the first network 2.

[0026] Hereinafter, when not specifying any one of a plurality of configurations such as the signal transfer devices 5-1 to 5-8, it is simply abbreviated as the signal transfer device 5 or the like.

[0027] FIG. 10 is a diagram showing a configuration example of the signal transfer device 5. As shown in FIG. 10, the signal transfer device 5 has, for example, a receiving unit 50, a signal distribution unit 51, a buffer unit 52, a time gate unit 53, a control unit 54, and a transmitting unit 55, and transfers the received signals by TAS.

[0028] The receiving unit 50 receives, for example, a plurality of signals including periodic signals with a higher priority than other signals, and outputs the received signals to the signal distribution unit 51 respectively. Further, the receiving unit 50 receives the instruction output by the signal transfer control device 6 and outputs it to the control unit 54.

[0029] The signal distribution unit 51 has a function of distributing each of the signals input from the receiving unit 50 according to the priority, and outputs the signals distributed according to the priority to the buffer unit 52 respectively.

[0030] The buffer unit 52 includes a plurality of buffers 520 that hold signals according to priority. The plurality of buffers 520 each hold the signals distributed by the signal distribution unit 51 according to priority. That is, the plurality of buffers 520 each hold the plurality of signals received by the receiving unit 50 according to priority.

[0031] The time gate unit 53 has a plurality of gates 530 corresponding to the plurality of buffers 520 respectively. The gate 530 transmits the signal held by the buffer 520 to the transmission unit 55 when it opens, and stops the transmission of the signal held by the buffer 520 to the transmission unit 55 when it closes.

[0032] The control unit 54 is a scheduler that controls the signal transmission for each buffer 520 by controlling the opening and closing of each of the plurality of gates 530 included in the time gate unit 53 according to, for example, an instruction (schedule information) notified from the signal transfer control device 6. The schedule information includes a gate opening period and a gate opening start time according to the priority of the signal by the TAS.

[0033] For example, the control unit 54 executes the TAS according to the schedule information notified from the signal transfer control device 6. At this time, the control unit 54 controls to open the gate 530 at a timing determined based on the period information, phase information, and data length of the signal included in the schedule information. For example, the control unit 54 preferentially controls to open the corresponding gate 530 for the buffer 520 that holds a signal with a higher priority.

[0034] The transmission unit 55 has a transfer function of transmitting the signal for which the gate 530 has been opened to a specified output destination. That is, the transmission unit 55 transmits the signals output by the plurality of buffers 520 according to the control of the control unit 54.

[0035] FIG. 11 is a diagram showing a configuration example of the signal transfer control device 6. As shown in FIG. 11, the signal transfer control device 6 has, for example, a path information storage unit 60, a distance information storage unit 61, an instruction determination unit 62, and an output unit 63.

[0036] The path information storage unit 60 stores path information indicating a plurality of paths constituted by, for example, a plurality of signal transfer devices 5, and outputs the path information to the instruction determination unit 62 upon access from the instruction determination unit 62.

[0037] The distance information storage unit 61 stores distance information indicating the distance of each path indicated by the path information stored in the path information storage unit 60, for example, and outputs the distance information to the instruction determination unit 62 upon access from the instruction determination unit 62.

[0038] The instruction determination unit 62 determines instructions (schedule information) for each of the plurality of signal transfer devices 5 based on the path information and the distance information, and outputs the determined instructions to the output unit 63.

[0039] The output unit 63 outputs (transmits) the instructions output by the instruction determination unit 62 to each of the plurality of signal transfer devices 5.

[0040] Next, an operation example of the signal transfer system 1 (FIG. 9) will be described. When transferring signals from the distributed stations 10-1 and 10-2 to the upper device 12, the first network 2 determines a path through a plurality of signal transfer devices 5 in accordance with the control of the signal transfer control device 6-1, and transfers the signals transmitted by the distributed stations 10-1 and 10-2 to the central station 4 by the TAS along the determined path.

[0041] The central station 4 processes the signals transferred by the first network 2 and transfers them to the second network 3. The second network 3 determines a path through a plurality of signal transfer devices 5 in accordance with the control of the signal transfer control device 6-2, and transfers the signals transferred by the central station 4 to the upper device 12 by the TAS along the determined path.

[0042] In this way, in the signal transfer across the central station 4 in the signal transfer system 1, the schedule information of the first network 2 and the schedule information of the second network 3 are not coordinated.

[0043] That is, when reserving time slots in the second network 3, it is necessary to include a certain fixed time when setting the processing time by the central office 4. This fixed time is an estimated value. Therefore, in order to make traffic arrive within the time slot, it is necessary to add a margin to the reserved time, which may reduce the bandwidth utilization efficiency.

[0044] Therefore, the signal transfer system according to an embodiment described below is configured to be able to improve the bandwidth utilization efficiency even when transferring signals across a plurality of different networks that transfer signals by TAS.

[0045] (First Embodiment) FIG. 1 is a diagram showing a configuration example of a signal transfer system 1a according to the first embodiment. In the signal transfer system 1a, for example, a first network 2a and a second network 3a are connected via a central office 4a. And the signal transfer system 1a transfers signals (traffic) so that the distributed stations (lower devices) 10-1 and 10-2 perform two-way communication with the upper device 12 via the first network 2a, the central office 4a, and the second network 3a.

[0046] Hereinafter, in the signal transfer system 1a shown in FIG. 1, the same reference numerals are given to the configurations that are substantially the same as the configuration of the signal transfer system 1 shown in FIG. 9.

[0047] The first network 2a has, for example, signal transfer devices 5-1 to 5-4 and a signal transfer control device 7-1. The signal transfer devices 5-1 to 5-4 constitute a plurality of paths for transferring signals between the distributed stations 10-1 and 10-2 and the central office 4a.

[0048] Then, the signal transfer devices 5-1 to 5-4 transfer the signals transmitted by the distributed stations 10-1 and 10-2 to the central office 4a by TAS according to the control of the signal transfer control device 7-1. Also, the signal transfer devices 5-1 to 5-4 transfer the signals transmitted by the central office 4a to the distributed stations 10-1 and 10-2 by TAS according to the control of the signal transfer control device 7-1.

[0049] The signal transfer control device 7-1 determines a path for transferring signals between the distributed stations 10-1 and 10-2 and the central station 4a, outputs an instruction so that the signals are transferred through the determined path, and controls the signal transfer devices 5-1 to 5-4. Further, the signal transfer control device 7-1 transmits schedule information in the first network 2a to the signal transfer control device 7-2. In addition, the signal transfer control device 7-1 has a function of acquiring processing time information (described later) from the central station 4a.

[0050] The second network 3a includes, for example, signal transfer devices 5-5 to 5-8 and a signal transfer control device 7-2. The signal transfer devices 5-5 to 5-8 constitute a plurality of paths for transferring signals between the central station 4a and the upper device 12.

[0051] Then, the signal transfer devices 5-5 to 5-8 transfer the signals transmitted by the central station 4a to the upper device 12 by TAS according to the control of the signal transfer control device 7-2. In addition, the signal transfer devices 5-5 to 5-8 transfer the signals transmitted by the upper device 12 to the central station 4a by TAS according to the control of the signal transfer control device 7-2.

[0052] The signal transfer control device 7-2 determines a path for transferring signals between the central station 4a and the upper device 12, outputs an instruction so that the signals are transferred through the determined path, and controls the signal transfer devices 5-5 to 5-8. Further, the signal transfer control device 7-2 transmits schedule information in the second network 3a to the signal transfer control device 7-1. In addition, the signal transfer control device 7-2 has a function of acquiring processing time information (described later) from the central station 4a.

[0053] The central station 4a is, for example, a CU (Central Unit: centralized base station), and is an intermediate node for transferring signals from the first network 2a to the second network 3a or from the second network 3a to the first network 2a. That is, the central station 4a aggregates the upstream signals transferred through the first network 2a and transfers them to the second network 3a, and distributes and transfers the downstream signals transferred through the second network 3a to the first network 2a.

[0054] In this way, the signal transfer system 1a transfers signals so that the distributed stations 10-1 and 10-2 can perform two-way communication with the host device 12. Here, the case where the signal transfer system 1a transfers an upstream signal will be described as an example.

[0055] FIG. 2 is a diagram showing a configuration example of the signal transfer control device 7-2 according to the second embodiment. As shown in FIG. 2, the signal transfer control device 7-2 includes, for example, a path information storage unit 70, a distance information storage unit 71, a first acquisition unit 72, an open period calculation unit 73, an acquisition time calculation unit 74, a second acquisition unit 75, a processing time storage unit 76, a time acquisition unit 77, a determination unit 78, and an output unit 79. For example, the signal transfer control device 7-2 controls a signal transfer schedule for transferring signals from the central station 4a to the second network 3a. Note that the signal transfer control device 7-1 has the same configuration as the signal transfer control device 7-2.

[0056] The path information storage unit 70 stores, for example, path information indicating a plurality of paths configured by a plurality of signal transfer devices 5, and outputs the path information to the determination unit 78 upon access from the determination unit 78.

[0057] The distance information storage unit 71 stores, for example, distance information indicating the distance of each path indicated by the path information stored in the path information storage unit 70, and outputs the distance information to the determination unit 78 upon access from the determination unit 78.

[0058] The first acquisition unit 72 acquires, for example, first schedule information indicating a schedule for the signal transfer device 5-2 that last transfers a signal to the central station 4a within the first network 2a to transfer the signal by the TAS from the signal transfer control device 7-1. Then, the first acquisition unit 72 outputs the acquired first schedule information to the open period calculation unit 73 and the acquisition time calculation unit 74.

[0059] Further, the first acquisition unit 72 may acquire the first schedule information at a predetermined periodic first timing.

[0060] The release period calculation unit 73 acquires split point information between the central office 4a and the upper device 12 within the second network 3a. Further, the release period calculation unit 73 acquires absolute time difference information indicating the difference between the time in the first network 2a and the time in the second network 3a. Further, the release period calculation unit 73 acquires arrival interval information indicating the time interval at which processing time information indicating the time required for the processing performed by the central office 4a to transfer a signal to the second network 3a arrives. Further, the release period calculation unit 73 acquires the first schedule information from the first acquisition unit 72.

[0061] Then, based on the acquired respective information, the release period calculation unit 73 calculates the available bandwidth in the second network 3a, calculates the gate release period of each signal transfer device 5, and outputs, for example, the acquired information and the calculated result to the acquisition time calculation unit 74 and the output unit 79.

[0062] The acquisition time calculation unit 74 calculates an offset value required to set schedule information (gate release period and gate release start time) for the signal transfer device 5-5 that first transfers a signal within the second network 3a, and outputs the offset value to the time acquisition unit 77 together with the arrival interval (acquisition timing) information at the absolute time.

[0063] The second acquisition unit 75 acquires processing time information tβ(t) indicating the time required for the processing performed by the central office 4a to transfer the signal transferred from the first network 2a to the second network 3a, from the central office 4a. Then, the second acquisition unit 75 outputs the acquired processing time information and information indicating the interval (transmission timing from the central office 4a) at which the processing time information arrives from the central office 4a, to the processing time storage unit 76.

[0064] Further, the second acquisition unit 75 may acquire the processing time information at a predetermined periodic second timing different from the first timing of the first acquisition unit 72.

[0065] The processing time storage unit 76 stores the processing time information tβ(t) input from the second acquisition unit 75 and the information indicating the transmission timing from the central office 4a, and outputs it in response to an access from the time acquisition unit 77.

[0066] The time acquisition unit 77 associates the information (offset value, acquisition timing) input from the acquisition time calculation unit 74 with the information (processing time information, information indicating the transmission timing from the central office 4a) acquired from the processing time storage unit 76, and outputs it to the determination unit 78.

[0067] Based on the respective information input from the route information storage unit 70, the distance information storage unit 71, and the time acquisition unit 77, the determination unit 78 determines the second schedule information indicating the schedule for the signal transfer device 5-5 to transfer the signal by TAS, which is the first device in the second network 3a to transfer the signal transferred by the central office 4a, and outputs it to the output unit 79.

[0068] For example, when the gate opening time in the signal transfer device 5-2 is T1, the determination unit 78 sets the gate opening time of the signal transfer device 5-5 to T1 + D + tβ(t). Here, D is the transmission time between the signal transfer device 5-2 and the signal transfer device 5-5. Also, the determination unit 78 determines the second schedule information based on the bandwidth capable of transferring signals in the second network 3a.

[0069] FIG. 3 is a diagram illustrating the second schedule information determined by the determination unit 78. As shown in FIG. 3, the determination unit 78 determines the gate opening period and the gate opening disclosure time as the second schedule information.

[0070] That is, the determination unit 78 determines the schedule (second schedule information) for the signal transfer device 5-5 to transfer the signal transferred by the central office 4a by TAS based on the first schedule information acquired by the first acquisition unit 72 and the processing time information acquired by the second acquisition unit 75. At this time, the determination unit 78 synchronizes the time between the first network 2a and the second network 3a to determine the second schedule information.

[0071] Further, the determination unit 78 may determine the second schedule information based on the result of determining whether the time between the time when the first acquisition unit 72 acquires the first schedule information and the time when the second acquisition unit 75 acquires the processing time information is longer than the time indicated by the processing time information acquired by the second acquisition unit 75.

[0072] FIG. 4 is a diagram schematically illustrating a process in which the signal transfer control device 7-2 determines the second schedule information. The signal transfer control device 7-2 outputs the second schedule information (gate opening start time, gate opening period) to the signal transfer device 5-5.

[0073] The signal transfer control device 7-2 sets an offset based on the difference in absolute time, path information, distance information, and the processing time of the central office 4a in order to synchronize the time between the first network 2a and the second network 3a.

[0074] At this time, the timing of acquiring the schedule information of the signal transfer device 5-2 is deviated from the timing at which the central office 4a transmits the processing time information. Therefore, the signal transfer control device 7-2 corrects the timing deviation in order to determine the gate opening start time. For example, the signal transfer control device 7-2 performs correction using the processing time of the nearest central office 4a, the average value of the processing times, and the like.

[0075] Further, the signal transfer control device 7-2 acquires the Split point information of MFH and MBH and determines the gate opening period.

[0076] For example, the signal transfer control device 7-2 determines the second schedule information using the processing time of the central office 4a closest to the schedule timing of the signal transfer device 5-5. For example, it is assumed that the signal transfer control device 7-2 has previously acquired the interval (transmission timing from the central office 4a) at which the processing time information arrives from the central office 4a.

[0077] When the signal transfer control device 7-2 uses the notified processing time as an offset, it sets the processing time as follows, for example.

[0078] When t_set - t2 > processing time: Set the notified processing time to t2. When t_set - t2 ≤ processing time: Set the notified processing time to t1.

[0079] Then, the output unit 79 (Fig. 2) outputs the second schedule information determined by the determination unit 78 to the signal transfer device 5-5 that first transfers the signal transferred by the central office 4a within the second network 3a.

[0080] For example, the output unit 79 notifies the gate opening period and the gate opening disclosure time surrounded by the broken line in Fig. 3 to the signal transfer device 5-5 that first transfers the signal transferred by the central office 4a within the second network 3a as an instruction.

[0081] As described above, in the signal transfer system 1a, the central office 4a notifies the signal transfer control device 7-2 of the processing time information tβ(t), the signal transfer control device 7-2 determines the second schedule information, and notifies the second schedule information to the control unit 54 of the signal transfer device 5.

[0082] Therefore, the signal transfer system 1a according to the first embodiment can improve the bandwidth utilization efficiency even when transferring signals across a plurality of different networks for transferring signals.

[0083] (Second Embodiment) In the second embodiment, the difference from the first embodiment is that the signal transfer control device includes a correlation calculation unit and a prediction unit. In the second embodiment, the difference from the first embodiment will be mainly described.

[0084] FIG. 5 is a diagram showing a configuration example of the signal transfer control device 7-2 according to the second embodiment. As shown in FIG. 5, the signal transfer control device 7-2 includes, for example, a path information storage unit 70, a distance information storage unit 71, a first acquisition unit 72, an open period calculation unit 73, an acquisition time calculation unit 74, a second acquisition unit 75, a processing time storage unit 76, a correlation calculation unit 770, a prediction unit 780, a determination unit 790, and an output unit 80.

[0085] Then, the signal transfer control device 7-2 controls a signal transfer schedule for transferring a signal from the central office 4a to the second network 3a. Note that the signal transfer control device 7-1 has the same configuration as the signal transfer control device 7-2.

[0086] The path information storage unit 70 stores, for example, path information indicating a plurality of paths constituted by a plurality of signal transfer devices 5, and outputs the path information to the determination unit 790 in response to an access from the determination unit 790.

[0087] The distance information storage unit 71 stores, for example, distance information indicating the distance of each path indicated by the path information stored in the path information storage unit 70, and outputs the distance information to the determination unit 790 in response to an access from the determination unit 790.

[0088] The first acquisition unit 72 acquires, for example, from the signal transfer control device 7-1, first schedule information indicating a schedule for the signal transfer device 5-2 that last transfers a signal to the central office 4a in the first network 2a to transfer the signal by the TAS. Then, the first acquisition unit 72 outputs the acquired first schedule information to the open period calculation unit 73 and the acquisition time calculation unit 74.

[0089] Also, the first acquisition unit 72 may acquire the first schedule information at a predetermined periodic first timing.

[0090] The open period calculation unit 73 acquires split point information between the central office 4a and the upper device 12 within the second network 3a. Further, the open period calculation unit 73 acquires absolute time difference information indicating the difference between the time in the first network 2a and the time in the second network 3a. Further, the open period calculation unit 73 acquires arrival interval information indicating the time interval at which processing time information indicating the time required for the processing performed by the central office 4a to transfer a signal to the second network 3a arrives. Further, the open period calculation unit 73 acquires the first schedule information from the first acquisition unit 72.

[0091] Then, based on the acquired pieces of information, the open period calculation unit 73 calculates the available bandwidth in the second network 3a, calculates the gate open period of each signal transfer device 5, and outputs, for example, the acquired information and the calculated result to the acquisition time calculation unit 74 and the output unit 80.

[0092] The acquisition time calculation unit 74 calculates an offset value required to set schedule information (gate open period and gate open start time) for the signal transfer device 5-5 that first transfers a signal within the second network 3a, and outputs the arrival interval (acquisition timing) information at absolute time, the first schedule information, and the offset value to the determination unit 790.

[0093] For each signal transferred from the first network 2a, the second acquisition unit 75 acquires processing time information tβ(t) indicating the time required for the processing performed by the central office 4a to transfer the signal to the second network 3a from the central office 4a. Then, the second acquisition unit 75 outputs the acquired processing time information and information indicating the interval (transmission timing from the central office 4a) during which the processing time information arrives from the central office 4a to the processing time storage unit 76 and the correlation calculation unit 770.

[0094] Further, the second acquisition unit 75 may acquire the processing time information at a predetermined periodic second timing different from the first timing of the first acquisition unit 72.

[0095] The processing time storage unit 76 stores the processing time information tβ(t) input from the second acquisition unit 75 and the information indicating the transmission timing from the central office 4a, and outputs it in response to an access from the prediction unit 780.

[0096] Based on the first schedule information acquired by the first acquisition unit 72 and the plurality of processing time information tβ(t) acquired by the second acquisition unit 75 for each signal, the correlation calculation unit 770 calculates the correlation between the amount of traffic flowing into the central office 4a and the time required for signal transfer processing. Then, the correlation calculation unit 770 outputs information indicating the calculated correlation to the prediction unit 780.

[0097] Based on the correlation calculated by the correlation calculation unit 770 and the processing time information acquired by the second acquisition unit 75 for each signal, the prediction unit 780 predicts the time required for signal transfer (predicted processing time: predicted processing delay amount) according to the traffic volume by the central office 4a.

[0098] For example, the prediction unit 780 may be configured to linearly approximate the traffic volume d and the value indicated by the processing time information tβ(t) based on the first schedule information and the plurality of processing time information stored in the processing time storage unit 76 to predict the predicted processing time. This is because the processing time at the central office 4a increases according to the amount of traffic flowing into the central office 4a. Then, the prediction unit 780 outputs information indicating the predicted time to the determination unit 790.

[0099] Based on each information input from the route information storage unit 70, the distance information storage unit 71, the acquisition time calculation unit 74, and the prediction unit 780, the determination unit 790 determines the second schedule information indicating the schedule for the signal transfer device 5-5 that first transfers the signal transferred by the central office 4a within the second network 3a to transfer the signal by the TAS, and outputs it to the output unit 80.

[0100] For example, when the gate opening time in the signal transfer device 5-2 is T1, the decision unit 790 may set the gate opening time of the signal transfer device 5-5 to T1 + D + tβ(t). Note that D is the transmission time between the signal transfer device 5-2 and the signal transfer device 5-5. Further, the decision unit 790 determines the second schedule information based on the bandwidth capable of transferring signals within the second network 3a.

[0101] As described above, in the signal transfer system 1a, the central office 4a notifies the signal transfer control device 7-2 of the processing time information tβ(t), and the signal transfer control device 7-2 determines the second schedule information based on the first schedule information and the predicted processing time, and notifies the second schedule information to the control unit 54 of the signal transfer device 5.

[0102] Therefore, the signal transfer system 1a according to the second embodiment can improve the bandwidth utilization efficiency even when transferring signals across a plurality of different networks for transferring signals.

[0103] In addition, in the signal transfer system 1a, since the signal transfer control device 7-2 predicts the predicted processing time according to the traffic volume of the central office 4a and determines the second schedule information, the processing load of the signal transfer control device 7-2 is lighter than the case of obtaining the processing time in the central office 4a for each packet and determining the second schedule information.

[0104] (Third Embodiment) In the first and second embodiments, in the signal transfer system 1a in which the networks of the signal transfer devices 5 (for example, layer 2 switches) connected via the central office 4a cooperate, the schedule information of the signal transfer control device 7-1 ("N-1" ("N" is an integer of 2 or more) nodes) and the processing time of the central office 4a (intermediate node) may be notified to the scheduler of the signal transfer control device 7-2 (N nodes) "packet by packet".

[0105] In this case, for example, the processing load of the signal transfer control device 7-2 (the load of the reception process of the information transmitted from the signal transfer control device 7-1 to the signal transfer control device 7-2) and the load of the calculation process (derivation process) in the signal transfer control device 7-1 increase. Thus, since high-functional processing capabilities are required for each signal transfer control device 7, the cost of each signal transfer control device 7 may increase.

[0106] Therefore, in the third embodiment, a signal transfer control device capable of suppressing an increase in at least one of the reception process and the calculation process in the signal transfer control device 7 will be mainly described with reference to the differences from the first and second embodiments.

[0107] FIG. 6 is a diagram showing a configuration example of the signal transfer control device 7 according to the third embodiment. The signal transfer control device 7 includes a path information storage unit 70, a distance information storage unit 71, a first acquisition unit 72, an open period calculation unit 73, an acquisition time calculation unit 74, a second acquisition unit 75, a processing time storage unit 76, a correlation calculation unit 770, a prediction unit 780, a determination unit 790, an output unit 80, a change amount determination unit 81, an information update unit 82, a cycle instruction unit 83, and a communication unit 84.

[0108] The change amount determination unit 81 acquires the first schedule information as cooperation information from the first acquisition unit 72 or the communication unit 84. The cooperation information is information used for cooperation of the schedule information of each connected network.

[0109] The cooperation information may include information defined in at least one of, for example, "O-RAN (Open Radio Access Network) CTI (Cooperative transport interface)", "ITU-T G.989.3 Amd3.G.sul66", "3GPP (Third Generation Partnership Project) TS28.552", "3GPP TS38.300", "3GPP TS23.502 4.2.2", "3GPP TS38.401", and "3GPP TS23.401 5.3.2".

[0110] For example, the cooperation information includes, as information related to the traffic volume (bandwidth information), schedule information (O-RAN CTI) (ITU-T G.989.3 Amd3.G.sul66). The schedule information may be, for example, downlink control information (DCI: Downlink Control Information). For example, the cooperation information may include average throughput information as information related to the traffic volume.

[0111] For example, the cooperation information may include information "UE active number" (3GPP TS28.552) related to the number of connections of wireless terminals (not shown) in the cell. For example, the cooperation information may include "Registration information" (UE Registration) (3GPP TS23.502 4.2.2, TS38.401) as information related to the number of connections of wireless terminals (not shown) for each distributed station 10.

[0112] The change amount determination unit 81 of the signal transfer control device 7-1 derives the change amount of the traffic in the distributed station 10 based on the cooperation information acquired from the distributed station 10. The change amount determination unit 81 of the signal transfer control device 7-2 may derive the change amount of the traffic in the signal transfer device 5-2 based on the cooperation information acquired from the signal transfer control device 7-1.

[0113] The change amount determination unit 81 compares the change amount of the traffic with a predetermined threshold value "α". The change amount determination unit 81 outputs the comparison result to the period instruction unit 83.

[0114] When the information update unit 82 of the signal transfer control device 7-2 acquires a trigger signal by the communication unit 84, it updates the second schedule information based on the cooperation information. The information update unit 82 may transmit the second schedule information as the first schedule information to other signal transfer control devices 7 via the communication unit 84.

[0115] Note that the information update unit 82 may obtain the second schedule information from the determination unit 790. The information update unit 82 may transmit the second schedule information as the first schedule information to another signal transfer control device 7 via the communication unit 84. The information update unit 82 may output a trigger signal to the determination unit 790. When the trigger signal is input from the information update unit 82, the determination unit 790 may generate the second schedule information.

[0116] When the amount of change in traffic is less than a predetermined threshold “α”, the period instruction unit 83 transmits an instruction of a notification period indicating a predetermined first period (for example, 1 ms) to the communication unit 84. When the amount of change in traffic is greater than or equal to the predetermined threshold “α”, the period instruction unit 83 transmits an instruction of a notification period indicating a predetermined second period (for example, 125 μs) to the communication unit 84.

[0117] The communication unit 84 executes communication with another connected signal transfer control device 7. The communication unit 84 transmits an instruction of the notification period determined by the period instruction unit 83 to another signal transfer control device 7 connected to the communication unit 84. The instruction of the notification period is, for example, an instruction of the notification period of the first schedule information.

[0118] The communication unit 84 acquires cooperation information from another signal transfer control device 7 connected to the communication unit 84. The communication unit 84 acquires a trigger signal from another signal transfer control device 7 connected to the communication unit 84. The communication unit 84 may acquire cooperation information from the distributed station 10 connected to the communication unit 84. The communication unit 84 transmits the schedule information to another signal transfer control device 7 at the period indicated by the instruction of the notification period.

[0119] FIG. 7 is a sequence diagram showing an operation example of the signal transfer control device 7 according to the third embodiment. The distributed station 10 transmits the cooperation information in the distributed station 10 (hereinafter referred to as “distributed station cooperation information”) to the signal transfer control device 7-1 (step S101). The signal transfer control device 7-1 acquires the distributed station cooperation information (step S102).

[0120] The signal transfer control device 7-1 ("N-1" node) determines the change amount (fluctuation amount) of traffic. For example, the signal transfer control device 7-1 compares the change amount of the traffic of the distribution station 10 with the threshold value "α" (step S103). When the change amount of the traffic is equal to or greater than the threshold value "α", the signal transfer control device 7-1 updates the second schedule information in the "N-1" node. The signal transfer control device 7-1 may update the cooperation information in the "N-1" node (step S104).

[0121] For example, when the change amount of the traffic of the distribution station 10 is less than the threshold value "α", the signal transfer control device 7-1 transmits the updated second schedule information in the "N-1" node to the signal transfer control device 7-2 (N node) at a predetermined notification period (for example, a 1 ms period). The signal transfer control device 7-1 may transmit the updated cooperation information in the "N-1" node to the signal transfer control device 7-2 at the same notification period (step S105).

[0122] The signal transfer control device 7-2 acquires the updated second schedule information in the signal transfer control device 7-1 ("N-1" node) from the signal transfer control device 7-1 at a predetermined notification period (for example, a 1 ms period) as the first schedule information for the signal transfer control device 7-2. The signal transfer control device 7-2 may acquire the updated cooperation information in the "N-1" node from the signal transfer control device 7-1 at the same notification period (step S106).

[0123] For example, when the change amount of the traffic of the distribution station 10 is equal to or greater than the threshold value "α", the signal transfer control device 7-1 transmits a trigger signal to the signal transfer control device 7-2 (N node) (step S107).

[0124] When the signal transfer control device 7-2 acquires a trigger signal, it determines the amount of change in traffic. For example, the signal transfer control device 7-2 determines the amount of change in traffic of the signal transfer device 5-2 or the central office 4a (step S108). The signal transfer control device 7-2 updates the second schedule information in the signal transfer control device 7-2 (N node) (step S109).

[0125] For example, when the amount of change in traffic of the signal transfer device 5-2 or the central office 4a is equal to or greater than the threshold value "α", the signal transfer control device 7-2 transmits an instruction of a notification period indicating a period shorter than the notification period in step S105 (for example, a 125 μs period) to the signal transfer control device 7-1 (step S110).

[0126] Note that when the amount of change in traffic per unit time is equal to or greater than the threshold value "α", the signal transfer control device 7 may derive the future required bandwidth (prediction result) by multiplying the number of connections and the traffic volume of wireless terminals (not shown) for each distributed station 10. Based on the prediction result, the signal transfer control device 7

[0127] The signal transfer control device 7-1 updates the period for notifying the signal transfer control device 7-2 of the second schedule information in the "N-1" node as the first schedule information to the instructed notification period (step S111). The signal transfer control device 7-1 transmits the second schedule information in the "N-1" node as the first schedule information to the signal transfer control device 7-2 at the updated notification period (for example, a 125 μs period) (step S112).

[0128] The signal transfer control device 7-2 acquires from the signal transfer control device 7-1 the second schedule information in the "N-1" node as the first schedule information at the updated notification period (for example, a 125 μs period) (step S113). The signal transfer control device 7-2 determines the amount of change in traffic (step S114). The signal transfer control device 7-2 updates the second schedule information in the N node (step S115).

[0129] As described above, the signal transfer system 1a includes a signal transfer control device 7-1 (first signal transfer control device) associated with the first network, and a signal transfer control device 7-2 (second signal transfer control device) associated with the second network connected to the first network via the central office 4a (intermediate node). The signal transfer control device 7-1 has a communication unit 84 (first communication unit) (second communication unit) of the signal transfer control device 7-1. The communication unit 84 of the signal transfer control device 7-1 transmits first schedule information indicating the schedule of signal transfer in the first network at a predetermined notification period. The communication unit 84 of the signal transfer control device 7-1 transmits a trigger signal based on the amount of change in the traffic of the first network. The signal transfer control device 7-2 includes a first acquisition unit 72 (acquisition unit), a communication unit 84 (third communication unit) of the signal transfer control device 7-2, a change amount determination unit 81, an information update unit 82, and a period instruction unit 83. The first acquisition unit 72 (acquisition unit) acquires the first schedule information at a predetermined notification period. The communication unit 84 (third communication unit) of the signal transfer control device 7-2 acquires the trigger signal from the communication unit 84 of the signal transfer control device 7-1. When the trigger signal is acquired, the change amount determination unit 81 determines whether the amount of change in the traffic of the first network is equal to or greater than the threshold "α" based on the first schedule information. When it is determined that the change amount is equal to or greater than the threshold, the information update unit 82 updates the second schedule information indicating the schedule of signal transfer in the second network. When it is determined that the change amount is equal to or greater than the threshold, the period instruction unit 83 instructs the signal transfer control device 7-1 of the predetermined notification period.

[0130] For example, in the signal transfer control device 7-2, the first acquisition unit 72 acquires the first schedule information from the signal transfer control device 7-1 at a predetermined notification period. The communication unit 84 acquires a trigger signal based on the change amount of the traffic of the first network from the signal transfer control device 7-1. When the trigger signal is acquired, the change amount determination unit 81 determines whether the change amount of the traffic of the first network is equal to or greater than a threshold value based on the first schedule information. When it is determined that the change amount is equal to or greater than the threshold value, the information update unit 82 updates the second schedule information. When it is determined that the change amount is equal to or greater than the threshold value, the period instruction unit 83 instructs the signal transfer control device 7-1 of a predetermined notification period.

[0131] In this way, in the third embodiment, it is possible to suppress an increase in the load of at least one of the reception process and the calculation process in the signal transfer control device 7.

[0132] Moreover, each function included in each of the signal transfer control devices 7-1 and 7-2, the central office 4a, and the signal transfer device 5 may be configured in part or in whole by hardware such as a PLD (Programmable Logic Device) or an FPGA (Field Programmable Gate Array), or may be configured as a program executed by a processor such as a CPU.

[0133] For example, the signal transfer control device 7 according to an embodiment can be realized using a computer and a program, and it is also possible to record the program on a storage medium or provide it through a network.

[0134] FIG. 8 is a diagram showing a hardware configuration example of the signal transfer control device 7 according to each embodiment. As shown in FIG. 8, for example, the signal transfer control device 7 includes an input unit 800, an output unit 810, a communication unit 820, a CPU 830, a memory 840, and an HDD 850 connected via a bus 860, and has functions as a computer. Further, the signal transfer control device 7 is enabled to input and output data to and from a computer-readable storage medium 870.

[0135] The input unit 800 is, for example, a keyboard and a mouse. The output unit 810 is a display device such as a display. The communication unit 820 is, for example, a network interface.

[0136] The CPU 830 controls each part constituting the signal transfer control device 7 and performs predetermined processing and the like. The memory 840 and the HDD 850 are storage units for storing data and the like.

[0137] The storage medium 870 can store a program and the like for causing the signal transfer control device 7 to execute its functions. Note that the architecture constituting the signal transfer control device 7 is not limited to the example shown in FIG. 8.

[0138] Regarding the signal transfer control device shown in the above first embodiment, the following supplementary notes are disclosed. (Supplementary Note A1) In a signal transfer control device that controls a signal transfer schedule of a signal transfer system that transfers a signal from a first network in which a plurality of signal transfer devices transfer signals to a second network in which a plurality of signal transfer devices transfer signals via an intermediate node, a first acquisition unit that acquires first schedule information indicating a schedule for a signal transfer device that finally transfers a signal to the intermediate node in the first network to transfer the signal; a second acquisition unit that acquires processing time information indicating the time required for processing performed by the intermediate node to transfer a signal transferred from the first network to the second network; a determination unit that determines second schedule information indicating a schedule for a signal transfer device that first transfers a signal transferred by the intermediate node in the second network to transfer the signal based on the first schedule information acquired by the first acquisition unit and the processing time information acquired by the second acquisition unit; and an output unit that outputs the second schedule information determined by the determination unit to a signal transfer device that first transfers a signal transferred by the intermediate node in the second network. A signal transfer control device characterized by comprising the above. (Appendix A2) The determination unit synchronizes the time between the first network and the second network to determine the second schedule information The signal transfer control device according to Appendix A1, characterized in that (Appendix A3) The first acquisition unit acquires the first schedule information at a predetermined periodic first timing, The second acquisition unit acquires the processing time information at a predetermined periodic second timing different from the first timing, The determination unit determines the second schedule information based on the result of determining whether the time between the time when the first acquisition unit acquires the first schedule information and the time when the second acquisition unit acquires the processing time information is longer than the time indicated by the processing time information acquired by the second acquisition unit The signal transfer control device according to Appendix A2, characterized in that (Appendix A4) The determination unit determines the second schedule information based on the bandwidth capable of transferring signals in the second network The signal transfer control device according to any one of Appendices A1 to A3, characterized in that (Appendix A5) In a signal transfer control method for controlling a signal transfer schedule of a signal transfer system that transfers a signal from a first network in which a plurality of signal transfer devices transfer signals to a second network in which a plurality of signal transfer devices transfer signals via an intermediate node, a first acquisition step of acquiring first schedule information indicating a schedule for a signal transfer device that transfers a signal to the intermediate node last in the first network; a second acquisition step of acquiring processing time information indicating the time required for processing performed by the intermediate node to transfer a signal transferred from the first network to the second network; A determination step of determining second schedule information indicating a schedule for a signal transfer device that first transfers in the second network the signal transferred by the intermediate node, based on the first schedule information and the processing time information; An output step of outputting the determined second schedule information to the signal transfer device that first transfers in the second network the signal transferred by the intermediate node; A signal transfer control method, characterized by including the above. (Appendix A6) A signal transfer control program for causing a computer to function as each part of the signal transfer control device according to any one of Appendices A1 to A4. (Appendix A7) A first network in which a plurality of signal transfer devices transfer signals; A second network in which a plurality of signal transfer devices transfer signals; An intermediate node that transfers a signal from the first network to the second network; A signal transfer control device that controls a signal transfer schedule for transferring a signal from the intermediate node to the second network; In a signal transfer system including: The signal transfer control device includes: A first acquisition unit that acquires first schedule information indicating a schedule for a signal transfer device that last transfers a signal to the intermediate node in the first network; A second acquisition unit that acquires processing time information indicating the time required for processing performed by the intermediate node to transfer the signal transferred from the first network to the second network; A determination unit that determines second schedule information indicating a schedule for a signal transfer device that first transfers in the second network the signal transferred by the intermediate node, based on the first schedule information acquired by the first acquisition unit and the processing time information acquired by the second acquisition unit; An output unit that outputs the second schedule information determined by the determination unit to the signal transfer device that first transfers in the second network the signal transferred by the intermediate node. A signal transfer system characterized by having (Appendix A8) The determination unit synchronizes the time between the first network and the second network to determine second schedule information The signal transfer system according to Appendix A7, characterized by

[0139] Regarding the signal transfer control device shown in the above second embodiment, the following appendices are disclosed. (Appendix B1) In a signal transfer control device that controls the signal transfer schedule of a signal transfer system that transfers signals from a first network where a plurality of signal transfer devices transfer signals to a second network where a plurality of signal transfer devices transfer signals via an intermediate node, a first acquisition unit that acquires first schedule information indicating a schedule for a signal transfer device that finally transfers a signal to the intermediate node within the first network to transfer the signal; a second acquisition unit that acquires processing time information indicating the time required for processing performed by the intermediate node to transfer a signal to the second network for each signal transferred from the first network; a correlation relationship calculation unit that calculates a correlation relationship between the amount of incoming traffic at the intermediate node and the time required for signal transfer processing based on the first schedule information acquired by the first acquisition unit and the plurality of pieces of processing time information acquired by the second acquisition unit for each signal; a prediction unit that predicts the time required for signal transfer according to the traffic volume by the intermediate node based on the correlation relationship calculated by the correlation relationship calculation unit and the processing time information acquired by the second acquisition unit for each signal; a determination unit that determines second schedule information indicating a schedule for a signal transfer device that first transfers a signal transferred by the intermediate node within the second network to transfer the signal based on the first schedule information acquired by the first acquisition unit and the time predicted by the prediction unit; An output unit that outputs the second schedule information determined by the determination unit to a signal transfer device that first transfers the signal transferred by the intermediate node within the second network, and A signal transfer control device characterized by comprising: (Appendix B2) The determination unit determines the second schedule information by synchronizing the time between the first network and the second network. The signal transfer control device according to Appendix B1, characterized by the above. (Appendix B3) The first acquisition unit acquires the first schedule information at a predetermined periodic first timing, The second acquisition unit acquires the processing time information at a predetermined periodic second timing different from the first timing, The determination unit determines the second schedule information based on the result of determining whether the time between the time when the first acquisition unit acquires the first schedule information and the time when the second acquisition unit acquires the processing time information is longer than the time indicated by the processing time information acquired by the second acquisition unit. The signal transfer control device according to Appendix B2, characterized by the above. (Appendix B4) The determination unit determines the second schedule information based on the bandwidth capable of transferring signals within the second network. The signal transfer control device according to any one of Appendices B1 to B3, characterized by the above. (Appendix B5) In a signal transfer control method for controlling a signal transfer schedule of a signal transfer system that transfers a signal from a first network in which a plurality of signal transfer devices transfer signals to a second network in which a plurality of signal transfer devices transfer signals via an intermediate node, a first acquisition step of acquiring first schedule information indicating a schedule for a signal transfer device that last transfers a signal to the intermediate node within the first network; A second acquisition step of acquiring processing time information indicating the time required for processing performed by the intermediate node to transfer a signal to the second network for each signal transferred from the first network; Based on the first schedule information acquired in the first acquisition step and the plurality of pieces of processing time information acquired for each signal in the second acquisition step, a correlation calculation step of calculating a correlation between the amount of incoming traffic at the intermediate node and the time required for signal transfer processing; A prediction step of predicting the time required for signal transfer according to the traffic volume by the intermediate node based on the calculated correlation and the processing time information acquired for each signal; Based on the first schedule information acquired in the first acquisition step and the time predicted in the prediction step, a determination step of determining second schedule information indicating a schedule for a signal transfer device that first transfers the signal transferred by the intermediate node within the second network to transfer the signal; An output step of outputting the determined second schedule information to a signal transfer device that first transfers the signal transferred by the intermediate node within the second network; A signal transfer control method characterized by including the above. (Appendix B6) A signal transfer control program for causing a computer to function as each part of the signal transfer control device according to any one of Appendices B1 to B4. (Appendix B7) A first network in which a plurality of signal transfer devices transfer signals; A second network in which a plurality of signal transfer devices transfer signals; An intermediate node that transfers a signal from the first network to the second network; A signal transfer control device that controls a signal transfer schedule for transferring a signal from the intermediate node to the second network; In a signal transfer system including the above, The signal transfer control device includes: A first acquisition unit that acquires first schedule information indicating a schedule for a signal transfer device that last transfers a signal to the intermediate node within the first network to transfer the signal; A second acquisition unit that acquires processing time information indicating the time required for processing performed by the intermediate node for each signal transferred from the first network for transfer to the second network; A correlation relationship calculation unit that calculates a correlation relationship between the amount of incoming traffic at the intermediate node and the time required for signal transfer processing based on the first schedule information acquired by the first acquisition unit and the plurality of pieces of processing time information acquired by the second acquisition unit for each signal; A prediction unit that predicts the time required for signal transfer according to the traffic volume by the intermediate node based on the correlation relationship calculated by the correlation relationship calculation unit and the processing time information acquired by the second acquisition unit for each signal; A determination unit that determines second schedule information indicating a schedule for a signal transfer device that first transfers the signal transferred by the intermediate node within the second network to transfer the signal based on the first schedule information acquired by the first acquisition unit and the time predicted by the prediction unit; An output unit that outputs the second schedule information determined by the determination unit to a signal transfer device that first transfers the signal transferred by the intermediate node within the second network A signal transfer system, characterized by comprising the above. (Appendix B8) The determination unit Synchronizes the time between the first network and the second network To determine the second schedule information The signal transfer system according to Appendix B7, characterized by the above.

Industrial Applicability

[0140] The present invention is applicable to an optical communication system such as an optical access system.

Explanation of Signs

[0141] 1, 1a... signal transfer system, 2, 2a... first network, 3, 3a... second network, 4, 4a... central office, 5-1 to 5-8... signal transfer device, 6-1, 6-2... signal transfer control device, 7-1, 7-2... signal transfer control device, 10-1, 10-2... distributed station, 12... upper device, 50... receiving unit, 51... signal oscillator unit, 52... buffer unit, 53... time gate unit, 54... control unit, 55... transmitting unit, 70... route information storage unit, 71... distance information storage unit, 72... first acquisition unit, 73... release period calculation unit, 74... acquisition time calculation unit, 75... second acquisition unit, 76... processing time storage unit, 77... time acquisition unit, 78... decision unit, 79... output unit, 80... output unit, 81... change amount determination unit, 82... information update unit, 83... cycle instruction unit, 84... communication unit, 520... buffer, 530... gate, 770... correlation relationship calculation unit, 780... prediction unit, 790... decision unit, 800... input unit, 810... output unit, 820... communication unit, 830... CPU, 840... memory, 850... HDD, 860... bus, 870... storage medium

Claims

1. A signal transfer control system comprising a first signal transfer control device associated with a first network and a second signal transfer control device associated with a second network connected to the first network via an intermediate node, wherein the first signal transfer control device, has a first communication unit that transmits first schedule information indicating a schedule for signal transfer in the first network at a predetermined notification period, and a second communication unit that transmits a trigger signal based on a change amount of traffic in the first network, wherein the second signal transfer control device, has an acquisition unit that acquires the first schedule information at the predetermined notification period, a third communication unit that acquires the trigger signal from the second communication unit, a change amount determination unit that determines, based on the first schedule information, whether or not the change amount of traffic in the first network is equal to or greater than a threshold value when the trigger signal is acquired, an information update unit that updates second schedule information indicating a schedule for signal transfer in the second network when it is determined that the change amount is equal to or greater than the threshold value, and a period instruction unit that instructs the first signal transfer control device of the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value, a signal transfer control system.

2. An acquisition unit that acquires first schedule information indicating a schedule for signal transfer in the first network from another signal transfer control device associated with the first network at a predetermined notification period, a communication unit that acquires a trigger signal based on a change amount of traffic in the first network from the other signal transfer control device, a change amount determination unit that determines, based on the first schedule information, whether or not the change amount of traffic in the first network is equal to or greater than a threshold value when the trigger signal is acquired, an information update unit that updates second schedule information indicating a schedule for signal transfer in a second network connected to the first network via an intermediate node when it is determined that the change amount is equal to or greater than the threshold value, and a period instruction unit that instructs the other signal transfer control device of the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value, a signal transfer control device comprising the above.

3. A signal transfer control method executed by a signal transfer control device, An acquisition step of acquiring, from another signal transfer control device associated with the first network, first schedule information indicating a schedule for signal transfer in the first network at a predetermined notification period; A communication step of acquiring, from the other signal transfer control device, a trigger signal based on a change amount of traffic in the first network; A change amount determination step of determining, based on the first schedule information, whether or not the change amount of traffic in the first network is equal to or greater than a threshold value when the trigger signal is acquired; An information update step of updating second schedule information indicating a schedule for signal transfer in a second network connected to the first network via an intermediate node when it is determined that the change amount is equal to or greater than the threshold value; A period instruction step of instructing the other signal transfer control device to perform the predetermined notification period when it is determined that the change amount is equal to or greater than the threshold value A signal transfer control method including the above steps.

4. A program for causing a computer to function as the signal transfer control device according to Claim 2.

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