Optical transmission control device, optical transmission system, method for optical transmission control device, and program

Abstract

To provide an optical transmission control device, an optical transmission system, and a method, and a program for the optical transmission control device, which change the transmission capacity of an optical transmission line on the basis of the amount of data to be transmitted.SOLUTION: In multiple optical transmission paths 14, an optical transmission control device 13 includes a selection unit 131 that selects a saturated optical transmission path 14s having an optical transmission utilization rate exceeding a first threshold value from among the multiple optical transmission paths connecting between a first optical transmission device 11 and a second optical transmission device 12, a determination unit 132 that determines an evacuation optical transmission path 14e from among the multiple optical transmission paths whose optical transmission direction is opposite to that of the saturated optical transmission path and whose optical transmission utilization rate is less than a second threshold value, a control unit 133 that transmits a movement control signal for moving data transmitted through a paired optical transmission path 14p that forms a pair with the saturated optical transmission path to the evacuation optical transmission path, and a path switching unit 134 that transmits a switching control signal for switching the optical transmission direction of the paired optical transmission path to the opposite direction after the movement of the data transmitted through the paired optical transmission paths is completed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an optical transmission control device, an optical transmission system, a method for an optical transmission control device, and a program, and in particular to an optical transmission control device, an optical transmission system, a method for an optical transmission control device, and a program that are capable of changing the transmission capacity of an optical transmission line based on the amount of data to be transmitted. [Background technology]

[0002] In core and metro networks of optical communications (optical transmission), upstream and downstream fibers are basically operated as one pair, with the communication capacity (transmission capacity) of each being fixed. In such cases, if traffic (data) increases and an imbalance occurs in the amount of data to be transmitted between the upstream and downstream, even if there is room in the overall capacity including the upstream and downstream, for example, when the amount of downstream data is so large that it reaches the capacity, a new fiber pair must be laid, which is an issue.

[0003] Patent Document 1 discloses that "an optical device having a bidirectional variable filter function is provided with one input / output terminal pair having a pair of input / output terminals and the other input / output terminal pair having a pair of input / output terminals, and is configured to output some optical signals from one input / output terminal constituting the input / output terminal pair to which no optical signal is input and output the remaining optical signals from the other input / output terminal constituting the input / output terminal pair to which no optical signal is input when a plurality of optical signals with different wavelengths are input from one input / output terminal constituting the input / output terminal pair of both input / output terminal pairs, and a first optical signal path switching unit is connected to the optical device and switches the input / output path of the optical signal between the optical device and the bidirectional optical signal transmission means by using an optical circulator. Patent Document 1 does not disclose that when an imbalance occurs between the amount of data to be transmitted in the upstream and downstream directions, the optical transmission direction is switched to flexibly change the transmission capacity of the upstream and downstream directions, or that the transmission capacity of the optical transmission line is changed based on the amount of data to be transmitted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-218729 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, when an imbalance occurs in the amount of data to be transmitted, there is a problem that new optical fiber pairs must be laid.

[0006] In order to solve the above-mentioned problems, an object of the present disclosure is to provide an optical transmission control device, an optical transmission system, an optical transmission control method, and a program capable of changing the transmission capacity of an optical transmission line based on the amount of data to be transmitted. [Means for solving the problem]

[0007] The optical transmission control device according to the present disclosure includes: a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the paired optical transmission paths is completed, for switching the optical transmission direction of the paired optical transmission paths to a reverse direction; Equipped with After the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction, the control unit transmits to the first optical transmission device and the second optical transmission device a distribution control signal for distributing a portion of the data transmitted through the saturated optical transmission path to the pair of optical transmission paths.

[0008] The optical transmission system according to the present disclosure comprises: a first optical transmission device, a second optical transmission device, a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device, and an optical transmission control device that controls the first optical transmission device and the second optical transmission device, the plurality of optical transmission paths include at least a first optical transmission path and a second optical transmission path, the first optical transmission line forms a pair with a downstream first optical transmission line from the first optical transmission device to the second optical transmission device and an upstream first optical transmission line from the second optical transmission device to the first optical transmission device; the second optical transmission path forms a pair with a downstream second optical transmission path from the first optical transmission device to the second optical transmission device and an upstream second optical transmission path from the second optical transmission device to the first optical transmission device; The optical transmission control device includes: a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold value from among the plurality of optical transmission paths; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the paired optical transmission paths is completed, for switching the optical transmission direction of the paired optical transmission paths to a reverse direction, the control unit transmits, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the paired optical transmission path after the optical transmission direction of the paired optical transmission path is switched to the opposite direction; The first optical transmission device is A first optical switching unit, a downstream first wavelength selection switching unit, and an upstream first wavelength selection switching unit, a first optical control unit that controls the first optical switching unit and the first downstream wavelength selection switching unit or the first upstream wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to be transmitted through the evacuation optical transmission line; a first optical transmit / receive switch that controls the first optical switch and the downstream first wavelength selection switch or the upstream first wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; the first optical control unit distributes a part of the data to be transmitted through the saturated optical transmission line to the paired optical transmission line based on the distribution control signal after the optical transmission direction of the paired optical transmission line is switched to the opposite direction; The second optical transmission device is A second optical switching unit, a downstream second wavelength selection switching unit, and an upstream second wavelength selection switching unit, a second optical control unit that controls the second optical switching unit and the downstream second wavelength selection switching unit or the upstream second wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to be transmitted through the evacuation optical transmission line; a second optical transmit / receive switch that controls the second optical switch and the downstream second wavelength selection switch or the upstream second wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; After the optical transmission direction of the paired optical transmission paths is switched to the opposite direction, the second optical control unit distributes a portion of the data to be transmitted through the saturated optical transmission path to the paired optical transmission path based on the distribution control signal.

[0009] The method for controlling an optical transmission according to the present disclosure includes: selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after the movement of the data transmitted through the paired optical transmission lines is completed; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; Equipped with.

[0010] The program according to the present disclosure is selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after the movement of the data transmitted through the paired optical transmission lines is completed; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; to be executed by the computer. Effect of the Invention

[0011] According to the present disclosure, it is possible to provide an optical transmission control device, an optical transmission system, an optical transmission control method, and a program capable of changing the transmission capacity of an optical transmission line based on the amount of data to be transmitted. [Brief description of the drawings]

[0012] [Figure 1] 1 is a block diagram illustrating an optical transmission control device according to the present disclosure. [Diagram 2] FIG. 1 is a block diagram illustrating an optical transmission system according to the present disclosure. [Diagram 3] FIG. 1 is a detailed block diagram illustrating an optical transmission system according to the present disclosure. [Figure 4] 4 is a flowchart illustrating an operation of a control device according to the present disclosure. [Diagram 5] FIG. 1 is a block diagram illustrating an optical transmission system according to the present disclosure. [Figure 6] FIG. 1 is a block diagram illustrating an optical transmission system according to the present disclosure. [Figure 7A] 7 is a block diagram illustrating a portion of the optical amplifier of FIG. 6. [Figure 7B] 7 is a block diagram illustrating a portion of the optical amplifier of FIG. 6. [Figure 8A] FIG. 1 is a block diagram illustrating an optical transmission system according to the present disclosure. [Figure 8B] 1 is a block diagram illustrating a Pump Combiner s / SW unit according to the present disclosure. [Figure 9] FIG. 1 is a block diagram illustrating a ROADM according to the present disclosure. [Figure 10]FIG. 1 is a block diagram illustrating a ROADM according to the present disclosure. [Figure 11] FIG. 1 is a block diagram illustrating a network using a node according to the present disclosure. [Figure 12] A block diagram illustrating Node 2 and Node 3 in accordance with the present disclosure. [Figure 13] A block diagram illustrating Node 2 and Node 3 in accordance with the present disclosure. [Figure 14] A block diagram illustrating Node 2 and Node 3 in accordance with the present disclosure. [Figure 15] A block diagram illustrating Node 2 and Node 3 in accordance with the present disclosure. [Figure 16] 11 is a sequence diagram illustrating the operation of Node 2 and Node 3 according to the present disclosure. [Figure 17] 11 is a sequence diagram illustrating the operation of Node 2 and Node 3 according to the present disclosure. [Figure 18] FIG. 1 is a block diagram illustrating a ROADM according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and duplicated descriptions will be omitted as necessary for clarity of description.

[0014] [Embodiment 1] <Configuration of optical transmission control device> FIG. 1 is a block diagram illustrating an optical transmission control device according to the present disclosure.

[0015] As shown in FIG. 1, the optical transmission control device 13 according to the present disclosure includes a selection unit 131, a specification unit 132, a control unit 133, and a route switching unit .

[0016] The selection unit 131 selects a saturated optical transmission line 14s having an optical transmission usage rate exceeding a first threshold value from among a plurality of optical transmission lines 14 connecting the first optical transmission device 11 and the second optical transmission device 12. The plurality of optical transmission lines 14 are composed of a first optical transmission line 141 to an n-th optical transmission line 14n. The n-th optical transmission line 14n is composed of a downstream n-th optical transmission line 14nd and an upstream n-th optical transmission line 14nu, where n is an integer equal to or greater than 1. The saturated optical transmission line 14s is, for example, the downstream first optical transmission line 141d. The optical transmission usage rate may also be referred to as a filling rate. The filling rate is the ratio of the wavelength band in use to the maximum wavelength band that can be transmitted through the optical transmission line.

[0017] The identifying unit 132 identifies the evacuation optical transmission path 14e from among the multiple optical transmission paths 14, the optical transmission direction of which is opposite to that of the saturated optical transmission path 14s and the optical transmission utilization rate of which is less than the second threshold. The reason for identifying the evacuation optical transmission path 14e from among the optical transmission paths having the opposite optical transmission direction is to change the transmission capacity of the upstream and downstream by switching the transmission direction when an imbalance occurs between the amounts of data to be transmitted in the upstream and downstream directions. In this case, by identifying an optical transmission path with a low utilization rate, the optical transmission utilization rate of which is less than the second threshold, more data can be evacuated to the evacuation optical transmission path 14e. Here, it is assumed that, for example, the upstream n-th optical transmission path 14nu is identified as the evacuation optical transmission path 14e. Note that the second threshold is lower than the first threshold.

[0018] The control unit 133 transmits a movement control signal to the first optical transmission device 11 and the second optical transmission device 12 to move data transmitted through the paired optical transmission path 14p, which is paired with the saturated optical transmission path 14s and has an optical transmission direction opposite to that of the saturated optical transmission path 14s, to the escape optical transmission path 14e. Since the saturated optical transmission path 14s is the downstream first optical transmission path 141d, the paired optical transmission path 14p which is paired with it is the upstream first optical transmission path 141u. By transmitting the movement control signal to the first optical transmission device 11 and the second optical transmission device 12 by the control unit 133, the first optical transmission device 11 and the second optical transmission device 12 operate to move data transmitted through the upstream first optical transmission path 141u (paired optical transmission path 14p) to the upstream n-th optical transmission path 14nu (escape optical transmission path 14e).

[0019] After completing the movement of the data transmitted through the paired optical transmission paths 14p to the evacuation optical transmission path 14e, the path switching unit 134 transmits a switching control signal for switching the optical transmission direction of the paired optical transmission paths 14p to the opposite direction to the first optical transmission device 11 and the second optical transmission device 12. When the path switching unit 134 transmits the switching control signal to the first optical transmission device 11 and the second optical transmission device 12, the first optical transmission device 11 and the second optical transmission device 12 operate to switch the optical transmission direction of the paired optical transmission path 14p to the opposite direction.

[0020] After the optical transmission direction of the paired optical transmission lines 14p is switched to the opposite direction, the control unit 133 transmits to the first optical transmission device 11 and the second optical transmission device 12 a distribution control signal for distributing a portion of the data transmitted through the saturated optical transmission line 14s to the paired optical transmission line 14p.

[0021] <Effects> As a result, even if an imbalance occurs in the amount of data to be transmitted, the optical transmission direction can be switched to flexibly change the upstream and downstream transmission capacities, making it possible to transmit data without laying a new optical transmission line.As a result, it is possible to provide an optical transmission control device, an optical transmission control method, and a program that can change the transmission capacity of the optical transmission line based on the amount of data to be transmitted.

[0022] Moreover, according to the first embodiment, since a paired optical transmission line that forms a pair with the saturated optical transmission line is used, the saturated optical transmission line and the paired optical transmission line are the same route. As a result, the saturated optical transmission line and the paired optical transmission line have the same transmission distance while passing through the same environment, and therefore have the same delay characteristics, etc., and can be easily received on the receiving side (for example, it is not necessary to perform delay compensation, etc., separately for the saturated optical transmission line and the paired optical transmission line).

[0023] <Optical transmission system configuration> FIG. 2 is a block diagram illustrating an optical transmission system according to the present disclosure. In Figure 2, the first optical transmit / receive switching unit and the first optical control unit of the first optical transmission device shown in Figure 3 are omitted for simplicity, and the second optical transmit / receive switching unit and the second optical control unit of the second optical transmission device are omitted for simplicity. FIG. 3 is a detailed block diagram illustrating an optical transmission system according to the present disclosure. In reality, the optical switching unit (SW) in Fig. 3 exists for each fiber pair as shown in Fig. 12, but for simplicity, they are collectively represented as one SW. The same applies to the wavelength selection switching unit (WSS) in Fig. 3.

[0024] As shown in Figures 2 and 3, the optical transmission system 10 according to the present disclosure includes a first optical transmission device 11, a second optical transmission device 12, a plurality of optical transmission paths 14 connecting between the first optical transmission device 11 and the second optical transmission device 12, and an optical transmission control device 13 that controls the first optical transmission device 11 and the second optical transmission device 12.

[0025] The multiple optical transmission paths 14 include at least a first optical transmission path 141 and a second optical transmission path 142. The first optical transmission path 141 forms a pair with a first downstream optical transmission path 141d from the first optical transmission device 11 to the second optical transmission device 12 and a first upstream optical transmission path 141u from the second optical transmission device 12 to the first optical transmission device 11. The second optical transmission path 142 forms a pair with a second downstream optical transmission path 142d from the first optical transmission device 11 to the second optical transmission device 12 and a second upstream optical transmission path 142u from the second optical transmission device 12 to the first optical transmission device 11.

[0026] The first optical transmission device 11 has a first optical switching unit 111, a downstream first wavelength selection switching unit 112d, an upstream first wavelength selection switching unit 112u, a first optical control unit 113, and a first optical transmit / receive switching unit 114. The first optical switching unit 111 is written as SW, which is an abbreviation for optical switch. The wavelength selection switching unit is written as WSS, which is an abbreviation for wavelength selective switch.

[0027] The first optical control unit 113 controls the first optical switching unit 111 and the downstream first wavelength selection switching unit 112d or the upstream first wavelength selection switching unit 112u to move the data transmitted through the paired optical transmission path 14p to be transmitted through the evacuation optical transmission path 14e based on the movement control signal.

[0028] After the movement of data transmitted through the paired optical transmission path 14p is completed, the first optical transmit / receive switching unit 114 controls the first optical switching unit 111 and the downstream first wavelength selection switching unit 112d or the upstream first wavelength selection switching unit 112u to switch the optical transmission direction of the paired optical transmission path 14p to the opposite direction based on the switching control signal.

[0029] After the optical transmission direction of the paired optical transmission line 14p is switched to the opposite direction, the first optical control unit 113 distributes a part of the data to be transmitted through the saturated optical transmission line 14s to the paired optical transmission line 14p based on the distribution control signal. The movement control signal, the switching control signal, and the distribution control signal are collectively referred to as the control signal.

[0030] The second optical transmission device 12 includes a second optical switching unit 121, a downstream second wavelength selection switching unit 122d, an upstream second wavelength selection switching unit 122u, a second optical control unit 123, and a second optical transmit / receive switching unit .

[0031] The second optical control unit 123 controls the second optical switching unit 121 and the downstream second wavelength selection switching unit 122d or the upstream second wavelength selection switching unit 122u to move the data transmitted through the pair optical transmission path 14p to be transmitted through the evacuation optical transmission path 14e based on the movement control signal.

[0032] After the movement of data transmitted through the paired optical transmission lines 14p is completed, the second optical transmit / receive switch 124 controls the second optical switch 121 and the downstream second wavelength selection switch 122d or the upstream second wavelength selection switch 122u to switch the optical transmission direction of the paired optical transmission lines 14p to the opposite direction based on the switching control signal. The downstream second wavelength selection switch 122d and the upstream second wavelength selection switch 122u may be wavelength selective switches (WSSs).

[0033] After the optical transmission direction of the optical transmission line pair 14p is switched to the opposite direction, the second optical control unit 123 distributes a part of the data to be transmitted through the saturated optical transmission line 14s to the optical transmission line pair 14p based on the distribution control signal.

[0034] The optical transmission device may also be called a node. The optical transmission control device 13 has already been described, so a description thereof will be omitted.

[0035] The first optical transmission device 11 may further include a wavelength conversion unit (not shown). When the evacuation optical wavelength of the optical carrier for carrying data transmitted through the evacuation optical transmission line 14e and the pair optical wavelength of the optical carrier for carrying data transmitted through the pair optical transmission line 14p are the same optical wavelength, they interfere with each other. In order to avoid such interference, the wavelength conversion unit converts the pair optical wavelength into an optical wavelength different from the evacuation optical wavelength.

[0036] <Operation of optical transmission control device> FIG. 4 is a flowchart illustrating the operation of the control device according to the present disclosure.

[0037] 4, the optical transmission control device 13 measures the optical transmission utilization rate of each optical transmission path between optical transmission devices (step S101). The optical transmission utilization rate may also be called a filling rate or a utilization rate.

[0038] The optical transmission control device 13 tallies up the optical transmission usage rates for each optical transmission path (step S102).

[0039] The optical transmission control device 13 checks whether the optical transmission utilization rate of any path exceeds the first threshold (step S103). That is, the optical transmission control device 13 selects an optical transmission path (saturated optical transmission path 14s) whose optical transmission utilization rate exceeds the first threshold from among the multiple optical transmission paths 14.

[0040] If step S103: YES, the optical transmission control device 13 checks whether the optical transmission utilization rate of the path that does not satisfy the condition of step S103 is less than the second threshold value (step S104). Specifically, the optical transmission control device 13 identifies an optical transmission path (rescue optical transmission path 14e) whose optical transmission direction is opposite to that of the saturated optical transmission path 14s and whose optical transmission utilization rate is less than the second threshold value from among the multiple optical transmission paths 14. If step S103: NO, the optical transmission control device 13 returns to step S101.

[0041] If step S104: YES, the optical transmission control device 13 aggregates data to be transmitted to a path (rescue optical transmission path 14e) whose optical transmission utilization rate is less than the second threshold (step S105). Specifically, the optical transmission control device 13 controls the first optical transmission device 11 and the second optical transmission device 12 so as to move data transmitted on the paired optical transmission path 14p, which is paired with the saturated optical transmission path 14s and has an optical transmission direction opposite to that of the saturated optical transmission path, to the rescue optical transmission path 14e. If step S104: NO, the optical transmission control device 13 returns to step S101. Data to be transmitted may also be called traffic.

[0042] In step S105, when aggregating data (traffic) transmitted through paths with optical transmission utilization rates less than the second threshold, if there are overlapping optical wavelengths in the evacuation optical transmission path 14e, the optical wavelength to be moved is dropped once, then wavelength converted and added. This makes it possible to avoid interference because the optical wavelength already in the evacuation optical transmission path 14e and the optical wavelength to be moved are no longer the same optical wavelength.

[0043] The optical transmission control device 13 confirms that there is no more data (step S106). Specifically, the optical transmission control device 13 confirms that the movement of the data transmitted through the paired optical transmission path 14p is completed and that there is no more data transmitted through the paired optical transmission path 14p.

[0044] The optical transmission control device 13 switches the transmission direction of the optical transmission line (the paired optical transmission line 14p) that no longer has data (step S107). Specifically, the optical transmission control device 13 switches the optical transmission direction of the paired optical transmission line 14p that no longer has data to transmit to the reverse direction.

[0045] The optical transmission control device 13 fills the data of the path (saturated optical transmission path 14s) that satisfies the first threshold value (step S108). Specifically, the optical transmission control device 13 controls the first optical transmission device 11 and the second optical transmission device 12 to distribute a part of the data transmitted through the saturated optical transmission path 14s to the paired optical transmission path 14p. As a result, the data transmitted through the saturated optical transmission path 14s is filled into the paired optical transmission path 14p.

[0046] <Effects> Since the optical transmission usage rate of data transmitted through the saturated optical transmission line 14s is reduced and data to be transmitted can be transmitted, there is no need to lay a new optical transmission line. As a result, it is possible to provide an optical transmission control device, a method for an optical transmission control device, and a program that can change the transmission capacity of the optical transmission line based on the amount of data to be transmitted.

[0047] [Variation 1] FIG. 5 is a block diagram illustrating an optical transmission system according to the present disclosure.

[0048] 5, the first optical transmission device 11c according to the first modification of the first embodiment differs from the first optical transmission device 11 (see FIG. 2) according to the first embodiment in that an optical circulator 111c is used instead of an optical switch as the first optical switching unit 111. Similarly, the second optical transmission device 12c differs from the second optical transmission device 12 in that an optical circulator 121c is used instead of an optical switch as the second optical switching unit 121.

[0049] An optical circulator is an optical device having directionality and can be used in place of an optical switch, that is, the first optical switching unit 111 and the second optical switching unit 121 may be an optical switch or an optical circulator.

[0050] [Variation 2] FIG. 6 is a block diagram illustrating an optical transmission system according to the present disclosure.

[0051] 6, a first optical transmission device 11p according to the second modification of the first embodiment includes a CoTX (Coherent Transmitter), a CoRX (Coherent Receiver), an optical circulator, and an optical amplifier. The optical amplifier includes a pump combiner and a pump LD (Laser Diode) connected thereto.

[0052] The Pump LD is used as pumping light when the optical amplifier operates. The Pump Combiner amplifies downstream data by using downstream data coming from the CoTX and pumping light pumped by the Pump LD. The system may further include optical amplifiers for amplifying data transmitted through a plurality of optical transmission paths. The Pump Combiner amplifies the upstream data by combining upstream data coming from the optical transmission path with pumping light pumped by the Pump LD.

[0053] The first optical transmission device 11p and the second optical transmission device 12 amplify downstream data and upstream data using a pump combiner and a pump LD. This makes it possible to transmit data over a longer distance than when an optical amplifier is not used.

[0054] <How to switch optical transmission direction> FIG. 7A is a block diagram illustrating a portion of the optical amplifier of FIG. FIG. 7A shows an optical transmission path before switching of the optical transmission direction. FIG. 7B is a block diagram illustrating a portion of the optical amplifier of FIG. FIG. 7B shows the optical transmission path after the optical transmission direction is switched.

[0055] When using an optical module amplifier such as an EDFA (Erbium Doped Fiber Amplifier) ​​as the optical amplifier, a 2x2 optical switch must be inserted in the input / output section, and control must be performed so that the input direction of the optical amplifier remains forward (input from the IN terminal and output from the OUT terminal) even when the path is switched. Optical amplifiers have an IN terminal and an OUT terminal, and data is always input from the IN terminal and output from the OUT terminal; reverse connection is not permitted. Therefore, when the optical transmission direction is switched, a switch or other device must be used to maintain the IN-OUT relationship of the optical amplifier. This relationship regarding the IN-OUT direction is called the forward direction.

[0056] Here, a specific method for making the input direction of the optical amplifier positive even when the path is switched will be described below.

[0057] As shown in Fig. 7A, the optical transmission path before the switching is "first terminal of the 2x2 optical switch → second terminal → IN terminal of the optical amplifier → OUT terminal → third terminal of the 2x2 optical switch → fourth terminal → second optical transmission device 12". On the other hand, as shown in Fig. 7B, the optical transmission path after the switching is "second optical transmission device 12 → fourth terminal of the 2x2 optical switch → second terminal → IN terminal of the optical amplifier → OUT terminal → third terminal of the 2x2 optical switch → first terminal".

[0058] By controlling the connection terminals of the 2x2 optical switch as shown in Figures 7A and 7B before and after switching the optical transmission direction, the optical transmission direction can be switched without swapping the IN and OUT terminals of the optical amplifier.

[0059] [Variation 3] FIG. 8A is a block diagram illustrating an optical transmission system in accordance with the present disclosure. FIG. 8B is a block diagram illustrating a Pump Combiner s / SW unit according to the present disclosure.

[0060] As shown in Fig. 8A, the first optical transmission device 11ps according to Modification Example 3 of Embodiment 1 is different from the first optical transmission device 11p (see Fig. 6) according to Modification Example 2 of Embodiment 1 in that a Pump Combiner w / SW, which is a combination of a Pump Combiner and a 1x2 optical switch, is provided instead of the Pump Combiner.

[0061] As shown in Fig. 8B, the optical transmission path before switching takes the path of "the first terminal of the 1x2 optical switch 11614 → the second terminal → the Pump Combiner 11611 → the second terminal of the 1x2 optical switch 11615 → the first terminal". At this time, the excitation light of the Pump LD takes the path of "the first terminal of the 1x2 optical switch 11613 → the second terminal → the Pump Combiner 11611" and is input to the Pump Combiner 11611.

[0062] On the other hand, the optical transmission path after switching takes the path of "the first terminal of the 1x2 optical switch 11615 → the third terminal → the Pump Combiner 11612 → the third terminal of the 1x2 optical switch 11614 → the first terminal". At this time, the excitation light of the Pump LD takes the path of "the first terminal of the 1x2 optical switch 11613 → the third terminal → the Pump Combiner 11612" and is input to the Pump Combiner 11612.

[0063] By controlling the connection terminals of the 1x2 optical switch as shown in Fig. 8B before and after switching the optical transmission direction, the optical transmission direction can be switched using the Pump Combiner s / SW1161.

[0064] [Embodiment 2] [Configuration 1 of ROADM] Fig. 9 is a block diagram illustrating a ROADM according to the present disclosure. Fig. 9 is a block diagram illustrating a normal two-way ROADM. That is, Fig. 9 is a block diagram illustrating a pair of ROADMs for the downstream and upstream optical fibers (optical transmission paths). The optical transmission path is, for example, an optical fiber. The optical fiber may also be referred to as a fiber.

[0065] In Embodiment 1, for the purpose of specializing the description for the features of the present disclosure, the configuration for branching / inserting an optical signal from the optical transmission device was omitted from the description. In Embodiment 2, a case where the technology of the present disclosure is applied to a ROADM (Reconfigurable Optical Add / Drop Multiplexer), which is one of the actual optical transmission devices, will be described. A ROADM may also be referred to as a Node or a node. Therefore, the first optical transmission device 11 and the second optical transmission device 12 may be composed of ROADM devices.

[0066] As shown in FIG. 9, a ROADM is a device capable of branching / inserting an optical signal and includes a WSS, a Boost, and a Pre. The WSS is a wavelength selective switch, the Boost is a transmission amplifier, and the Pre is a reception amplifier. TX Add is an input section to which data from the outside is input, and RX Drop is an output section for outputting data to the outside.

[0067] The optical signal (data) input to Pre2 is transmitted to WSS1 based on the wavelength selection of WSS3 and output to the outside via Boost1 based on the wavelength selection of WSS1. The optical signal (data) input to Pre1 is transmitted to WSS4 based on the wavelength selection of WSS2 and output to the outside via Boost2 based on the wavelength selection of WSS4.

[0068] <Configuration 2 of ROADM> FIG. 10 is a block diagram illustrating a ROADM according to the present disclosure. FIG. 10 is a block diagram illustrating a ROADM that processes one downlink fiber, one uplink fiber, and two bidirectional fibers.

[0069] As shown in FIG. 10, the upstream optical signal input to Pre4 is transmitted according to the direction of the arrow shown in FIG. 10. For example, the upstream optical signal input to Pre4 is amplified at Pre4, transmitted to WSS1 based on the wavelength selection of WSS7, amplified by Boost1 based on the wavelength selection of WSS1, and then output to the outside. Also, for example, the downstream optical signal input to Pre3 is amplified at Pre3, transmitted to WSS9 based on the wavelength selection of WSS6, amplified by Boost4 based on the wavelength selection of WSS9, and then output to the outside via Circulator3.

[0070] <Configuration of a network using <Node(ROADM)>> FIG. 11 is a block diagram illustrating a network using the Node according to the present disclosure.

[0071] As shown in FIG. 11, in this example, the network is configured by Node1 to Node8. This is just one example and is not limited thereto. Node2 is connected to Node1, Node3, and Node4, and Node3 is connected to Node2, Node7, and Node8. Here, in the fiber connected between Node2 and Node3, in addition to the normal fiber pair, there is a fiber pair that can be switched bidirectionally. Also, it is assumed that in the fiber connected between Node3 and Node8, in addition to the normal fiber pair, there is a fiber pair that can be switched bidirectionally. The following description will be made on the premise of these conditions.

[0072] <Operation of the Node> FIG. 12 is a block diagram illustrating Node2 and Node3 according to the present disclosure. FIG. 13 is a block diagram illustrating Node2 and Node3 according to the present disclosure. FIG. 14 is a block diagram illustrating Node2 and Node3 according to the present disclosure. FIG. 15 is a block diagram illustrating Node2 and Node3 according to the present disclosure. However, in Figs. 12 to 15, the optical transmission control device is omitted for simplicity.

[0073] FIG. 12 is a detailed block diagram illustrating Node 2 and Node 3 shown in FIG. FIG. 12 shows the connection state of the bidirectional fiber connected between Node 2 and Node 3 before switching from (Node 3-->Node 2) to (Node 2-->Node 3).

[0074] As shown in Fig. 12, Node 2 forms normal fiber pairs in three directions, i.e., with Node 1, Node 3, and Node 4, and forms a bidirectional fiber pair in one direction only, i.e., with Node 3. Node 3 forms normal fiber pairs in three directions, i.e., with Node 2, Node 7, and Node 8, and forms a bidirectional fiber pair in two directions only, i.e., with Node 2 and with Node 8.

[0075] 13 shows the connection state during switching of the bidirectional fiber from (Node3-->Node2) to (Node2-->Node3) when the fiber (Node2-->Node3) is selected as the saturated optical transmission path. In this connection state during switching, one of the connections of the bidirectional fiber pair between Node3 and Node2 (connection via Circulator4-->Circulator2) is being evacuated to the evacuation fiber (evacuation optical transmission path) between Node2 and Node3.

[0076] As shown in Fig. 13, during evacuation, among the multiple bidirectional fiber pairs to (Node 3 -> Node 2), for example, the fiber connected to Circulator 2 and Circulator 4 is selected as a saturated optical transmission line (connection shown by dashed lines in Fig. 13). Then, among the multiple bidirectional fiber pairs, the connection shown by solid lines in Fig. 13 is specified as the evacuation optical transmission line to Node 2. Then, the connection of the saturated optical transmission line is changed to the connection to the evacuation optical transmission line, and the traffic is evacuated.

[0077] Figure 14 shows the connection state between Node2 and Node3 when the evacuation movement of traffic is completed.

[0078] As shown in Figure 14, after the completion of the evacuation movement of traffic, in order to switch the bidirectional fiber from (Node3-->Node2) to (Node2-->Node3), the fiber connection is temporarily stopped. It can be understood that the forward path connection is not established at Node2 and Node3.

[0079] Figure 15 shows the connection state when both of the originally bidirectional fibers (Node2-->Node3) are switched to (Node2-->Node3). Note that for clarity, only the connections related to the corresponding bidirectional fibers are described for the connections between WSSs.

[0080] As shown in Figure 15, in order to allocate a part of the data transmitted on the saturated optical transmission path, (Node3-->Node2) is switched to the reverse direction, that is, (Node2-->Node3).

[0081] <Operation sequence of Node> Figure 16 is a sequence diagram illustrating the operations of Node2 and Node3 according to the present disclosure. Figure 16 shows the processing until the traffic in the (Node3-->Node2) direction in the bidirectional fiber stops. Figure 17 is a sequence diagram illustrating the operations of Node2 and Node3 according to the present disclosure. Figure 17 shows the processing until the traffic is filled after switching to the Node2-->Node3 direction.

[0082] 16, the optical transmission control device 13 requests measurement of the optical transmission utilization rate of each fiber between nodes (step S201). Node2 and Node3 each measure the optical transmission utilization rate (filling rate) (steps S202 and S203). The optical transmission control device 13 acquires the optical transmission utilization rates from Node2 and Node3, and tallies the optical transmission utilization rates by path (step S204).

[0083] The optical transmission control device 13 selects a saturated optical transmission path in which the optical transmission utilization rate (Node 2 → Node 3) exceeds a first threshold (step S205). The optical transmission control device 13 also identifies an evacuation optical transmission path in which the optical transmission utilization rate (Node 3 → Node 2) is less than a second threshold (step S206). The optical transmission control device 13 issues a switching instruction to Node 3 to switch from (Node 3 → Node 2) to (Node 2 → Node 3) (step S207). Note that amp and AMP refer to optical amplifiers or optical amplifiers.

[0084] Node 3 starts evacuating the traffic of the bidirectional fiber (saturated optical transmission path) from (Node 3 to Node 2) to another fiber (evacuation optical transmission path) (step S208). Therefore, Node 3 connects the traffic of the bidirectional fiber from (Node 3 to Node 2) to the other fiber and switches the fiber connection (step S209). Node 3 starts stopping control of the Boost AMP (step S210). Node 3 stops (turns off) the operation of the Boost AMP (step S211). Node 3 reports to the optical transmission control device that the bidirectional fiber from (Node 3 to Node 2) is ready to be switched (step S212).

[0085] 17, the optical transmission control device 13 issues a switching instruction for the bidirectional fiber of Node 2 (Node 2 → Node 3) to Node 2 and AMP SW (amplifier changeover switch) (step S301). The AMP SW stops (OFF) the connection to the amplifier.

[0086] Node 2 starts preparations for switching the bidirectional fiber of Node 2 (Node 2 → Node 3) (step S302). Node 2 stops (OFF) the Pre AMP (step S304). Node 2 reports to the optical transmission control device 13 that preparations for switching the bidirectional fiber of Node 2 (Node 2 → Node 3) are complete (step S305). The optical transmission control device 13 issues an instruction to switch the direction of the optical transmission path to Node 3 and the AMP SW (step S306).

[0087] Node 3 starts changing the transmission direction (step S308). Node 3 turns on the Pre AMP, switches the path, and turns on the Drop side (step S311). Node 3 reports the change in the transmission direction to the optical transmission control device 13 (step S312).

[0088] The AMP SW receives the direction switching instruction of the optical transmission line and switches the connection direction to the amplifier (step S307). The AMP SW starts (ON) the connection to the amplifier (step S309). The AMP SW sends an amplifier direction switching completion report to the optical transmission control device 13 (step S310).

[0089] The optical transmission control device 13 issues an instruction to Node 2 to start filling the bidirectional fiber (paired optical transmission path) whose direction is to be changed (step S313). That is, the optical transmission control device 13 issues an instruction to Node 2 to fill the paired optical transmission path with part of the data transmitted through the saturated optical transmission path. Node 2 starts filling the bidirectional fiber whose direction is to be changed with traffic (step S314). Node 2 fills the bidirectional fiber whose direction is to be changed with traffic (step S315). Node 2 reports to the optical transmission control device 13 that filling the bidirectional fiber whose direction is to be changed with traffic has been completed (step S316). The optical transmission control device 13 acquires that the direction change has been completed (step S317).

[0090] [Variations] FIG. 18 is a block diagram illustrating a ROADM according to the present disclosure. As shown in FIG. 18, the ROADM has a multi-core FIFO (Fan In / Fan Out) inserted on the input / output side, and can switch the communication direction between two directions in at least one core within one fiber.

[0091] In the above embodiment, the present disclosure has been described as a hardware configuration, but the present disclosure is not limited to this. The present disclosure can also be realized by having a CPU (Central Processing Unit) execute a computer program to process each component.

[0092] In the above embodiment, the program can be stored and supplied to the computer using various types of non-transitory computer readable media. The non-transitory computer readable media includes various types of tangible storage media. Examples of the non-transitory computer readable media include magnetic recording media (specifically, flexible disks, magnetic tapes, and hard disk drives), magneto-optical recording media (specifically, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, semiconductor memories (specifically, mask ROMs, PROMs (Programmable ROMs), and EPROMs (Erasable PROMs)), flash ROMs, and RAMs (Random Access Memory). The program may also be supplied to the computer by various types of transitory computer readable media. Examples of the transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer readable media can supply the program to the computer via wired communication paths such as electric wires and optical fibers, or wireless communication paths.

[0093] Additionally, although operations are depicted in a particular order, this should not be understood as requiring such operations to be performed in the particular order or sequential order depicted, or that all of the depicted operations be performed, to achieve desirable results. In certain situations, multitasking and parallel processing may be advantageous. Similarly, although details of several specific embodiments are included in the above discussion, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable combination.

[0094] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be appropriately combined with other embodiments.

[0095] Each drawing is merely an example for describing one or more embodiments. Each drawing may relate not only to one particular embodiment, but to one or more other embodiments. As can be understood by those skilled in the art, various features or steps described with reference to any one drawing may be combined with features or steps shown in one or more other drawings to create an embodiment not explicitly shown or described, for example. Not all features or steps shown in any one drawing are necessary to describe an exemplary embodiment, and some features or steps may be omitted. The order of steps described in any drawing may be changed as appropriate.

[0096] The present disclosure is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present disclosure.

[0097] A part or all of the above-described embodiments can be described as, but is not limited to, the following supplementary notes. (Appendix 1) a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the paired optical transmission paths is completed, for switching the optical transmission direction of the paired optical transmission paths to a reverse direction; Equipped with the control unit transmits, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of the data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction. Optical transmission control device. (Appendix 2) The second threshold is lower than the first threshold. 2. The optical transmission control device according to claim 1. (Appendix 3) The first optical transmission device and the second optical transmission device are configured as ROADM (Reconfigurable Optical Add / Drop Multiplexer) devices. 2. The optical transmission control device according to claim 1. (Appendix 4) further comprising an optical amplifier for amplifying each of the data transmitted through the plurality of optical transmission paths; 2. The optical transmission control device according to claim 1. (Appendix 5) a first optical transmission device, a second optical transmission device, a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device, and an optical transmission control device that controls the first optical transmission device and the second optical transmission device, the plurality of optical transmission paths include at least a first optical transmission path and a second optical transmission path, the first optical transmission line forms a pair with a downstream first optical transmission line from the first optical transmission device to the second optical transmission device and an upstream first optical transmission line from the second optical transmission device to the first optical transmission device; the second optical transmission path forms a pair with a downstream second optical transmission path from the first optical transmission device to the second optical transmission device and an upstream second optical transmission path from the second optical transmission device to the first optical transmission device; The optical transmission control device includes: a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold value from among the plurality of optical transmission paths; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the pair of optical transmission paths is completed, for switching the optical transmission direction of the pair of optical transmission paths to a reverse direction, the control unit transmits, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the paired optical transmission path after the optical transmission direction of the paired optical transmission path is switched to the opposite direction; The first optical transmission device is A first optical switching unit, a downstream first wavelength selection switching unit, and an upstream first wavelength selection switching unit, a first optical control unit that controls the first optical switching unit and the first downstream wavelength selection switching unit or the first upstream wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to be transmitted through the evacuation optical transmission line; a first optical transmit / receive switch that controls the first optical switch and the downstream first wavelength selection switch or the upstream first wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; the first optical control unit distributes a part of the data to be transmitted through the saturated optical transmission line to the paired optical transmission line based on the distribution control signal after the optical transmission direction of the paired optical transmission line is switched to the opposite direction; The second optical transmission device is A second optical switching unit, a downstream second wavelength selection switching unit, and an upstream second wavelength selection switching unit, a second optical control unit that controls the second optical switching unit and the downstream second wavelength selection switching unit or the upstream second wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to be transmitted through the evacuation optical transmission line; a second optical transmit / receive switch that controls the second optical switch and the downstream second wavelength selection switch or the upstream second wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; the second optical control unit distributes a part of the data to be transmitted through the saturated optical transmission line to the paired optical transmission line based on the distribution control signal after the optical transmission direction of the paired optical transmission line is switched to the opposite direction; Optical transmission system. (Appendix 6) The first optical transmission device is a wavelength conversion unit that converts the pair optical wavelength into an optical wavelength different from the evacuation optical wavelength when the evacuation optical wavelength of the optical carrier for carrying data transmitted through the evacuation optical transmission path and the pair optical wavelength of the optical carrier for carrying data transmitted through the pair optical transmission path are the same optical wavelength; 6. The optical transmission system according to claim 5. (Appendix 7) The first optical switching unit and the second optical switching unit are optical switches or optical circulators. 6. The optical transmission system according to claim 5. (Appendix 8) the downstream first wavelength selection switching unit, the upstream first wavelength selection switching unit, the downstream second wavelength selection switching unit, and the upstream second wavelength selection switching unit are wavelength selective switches (WSSs); 6. The optical transmission system according to claim 5. (Appendix 9) selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after the movement of the data transmitted through the paired optical transmission lines is completed; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; The optical transmission control device according to claim 1, (Appendix 10) selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after the movement of the data transmitted through the paired optical transmission lines is completed; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; A program that causes a computer to execute the following. [Explanation of symbols]

[0098] 10, 10c, 10p...Optical transmission system 11, 11c, 11p...first optical transmission device 111...First optical switching unit 111c...Optical circulator 112d... Downstream first wavelength selection switch unit 112u…Upstream first wavelength selection switch 113...first light control unit 114...first optical transmission / reception switching unit 12, 12c, 12p...Second optical transmission device 121...Second optical switching unit 121c…Optical circulator 122d... Downstream second wavelength selection switch unit 122u: upstream second wavelength selection switch 123...Second light control unit 124...Second optical transmission / reception switching unit 13...Optical transmission control device 131...Selection section 132…Specific part 133...Control unit 134…Route switching section 14...Multiple optical transmission paths 141...First optical transmission line 141d…Downstream first optical transmission line 141u…First upstream optical transmission line 14n...nth optical transmission line 14nd: Downstream nth optical transmission line 14nu…Upstream nth optical transmission line 14s…Saturated optical transmission line 14e...Evacuation optical transmission line 14p...Pair optical transmission line

Claims

1. a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the paired optical transmission paths is completed, for switching the optical transmission direction of the paired optical transmission paths to a reverse direction; Equipped with the control unit transmits, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction. Optical transmission control device.

2. The second threshold is lower than the first threshold.

2. The optical transmission control device according to claim 1.

3. The first optical transmission device and the second optical transmission device are configured as ROADM (Reconfigurable Optical Add / Drop Multiplexer) devices.

2. The optical transmission control device according to claim 1.

4. further comprising an optical amplifier for amplifying each of the data transmitted through the plurality of optical transmission paths; 2. The optical transmission control device according to claim 1.

5. a first optical transmission device, a second optical transmission device, a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device, and an optical transmission control device that controls the first optical transmission device and the second optical transmission device, the plurality of optical transmission paths include at least a first optical transmission path and a second optical transmission path, the first optical transmission line forms a pair with a downstream first optical transmission line from the first optical transmission device to the second optical transmission device and an upstream first optical transmission line from the second optical transmission device to the first optical transmission device; the second optical transmission path forms a pair with a downstream second optical transmission path from the first optical transmission device to the second optical transmission device and an upstream second optical transmission path from the second optical transmission device to the first optical transmission device; The optical transmission control device includes: a selection unit that selects a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold value from among the plurality of optical transmission paths; a specifying unit that specifies an escape optical transmission path from among the plurality of optical transmission paths, the escape optical transmission path having an optical transmission direction opposite to that of the saturated optical transmission path and an optical transmission utilization rate less than a second threshold; a control unit that transmits, to the first optical transmission device and the second optical transmission device, a movement control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path to the evacuation optical transmission path; a path switching unit that transmits a switching control signal to the first optical transmission device and the second optical transmission device after the movement of data transmitted through the pair of optical transmission paths is completed, for switching the optical transmission direction of the pair of optical transmission paths to a reverse direction, the control unit transmits, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the paired optical transmission path after the optical transmission direction of the paired optical transmission path is switched to the opposite direction; The first optical transmission device is A first optical switching unit, a downstream first wavelength selection switching unit, and an upstream first wavelength selection switching unit, a first optical control unit that controls the first optical switching unit and the first downstream wavelength selection switching unit or the first upstream wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to transmit the data through the evacuation optical transmission line; a first optical transmit / receive switch that controls the first optical switch and the downstream first wavelength selection switch or the upstream first wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; the first optical control unit distributes a part of the data to be transmitted through the saturated optical transmission line to the paired optical transmission line based on the distribution control signal after the optical transmission direction of the paired optical transmission line is switched to the opposite direction; The second optical transmission device is a second optical switching unit, a downstream second wavelength selection switching unit, and an upstream second wavelength selection switching unit; a second optical control unit that controls the second optical switching unit and the downstream second wavelength selection switching unit or the upstream second wavelength selection switching unit to move the data transmitted through the paired optical transmission lines based on the movement control signal so as to be transmitted through the evacuation optical transmission line; a second optical transmit / receive switch that controls the second optical switch and the downstream second wavelength selection switch or the upstream second wavelength selection switch to switch the optical transmission direction of the paired optical transmission lines to a reverse direction based on the switching control signal after the movement of data transmitted through the paired optical transmission lines is completed; the second optical control unit distributes a part of the data to be transmitted through the saturated optical transmission line to the paired optical transmission line based on the distribution control signal after the optical transmission direction of the paired optical transmission line is switched to the opposite direction; Optical transmission system.

6. The first optical transmission device is a wavelength conversion unit that converts the pair optical wavelength into an optical wavelength different from the evacuation optical wavelength when the evacuation optical wavelength of the optical carrier for carrying data transmitted through the evacuation optical transmission path and the pair optical wavelength of the optical carrier for carrying data transmitted through the pair optical transmission path are the same optical wavelength; 6. The optical transmission system according to claim 5.

7. The first optical switching unit and the second optical switching unit are optical switches or optical circulators.

6. The optical transmission system according to claim 5.

8. the downstream first wavelength selection switching unit, the upstream first wavelength selection switching unit, the downstream second wavelength selection switching unit, and the upstream second wavelength selection switching unit are wavelength selective switches (WSSs); 6. The optical transmission system according to claim 5.

9. selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after completion of the movement of the data transmitted through the paired optical transmission lines; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; The optical transmission control device according to claim 1,

10. selecting a saturated optical transmission path having an optical transmission utilization rate exceeding a first threshold from among a plurality of optical transmission paths connecting the first optical transmission device and the second optical transmission device; identifying an evacuation optical transmission path from among the plurality of optical transmission paths, the optical transmission direction of which is opposite to that of the saturated optical transmission path and the optical transmission utilization rate of which is less than a second threshold; transmitting, to the first optical transmission device and the second optical transmission device, a control signal for moving data transmitted on a paired optical transmission path that is paired with the saturated optical transmission path and has an optical transmission direction opposite to that of the saturated optical transmission path, to the evacuation optical transmission path; transmitting a switching control signal for switching an optical transmission direction of the paired optical transmission lines to a reverse direction to the first optical transmission device and the second optical transmission device after completion of the movement of the data transmitted through the paired optical transmission lines; transmitting, to the first optical transmission device and the second optical transmission device, a distribution control signal for distributing a part of data transmitted through the saturated optical transmission path to the pair of optical transmission paths after the optical transmission direction of the pair of optical transmission paths is switched to the opposite direction; A program that causes a computer to execute the following.

Images