JP2011147077A - Protection switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To confirm normal operation of a redundant path during ordinary operation. <P>SOLUTION: A protection switch includes: a transmitting switch section 3 having a redundant port for connecting with a transmitting side of an active path and an idle port; a receiving switch section 4, which has a redundant port for connecting with a receiving side of the active path and a monitor port for measuring an optical signal outputted by the receiving switch section itself, the receiving switch section receiving an optical signal from the transmitting switch; and a switch control/monitor supervisory section 6 for controlling a connection switching operation to the idle port of the transmitting switch section 3 and to the monitor port of the receiving switch section 4, monitoring the optical signal measured via the monitor port, and confirming normality of the transmitting switch section. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a protection switch that confirms its normality in a protection switch that functions as a redundant path for an operation path that transmits an optical signal, for example.

  The N + 1 protection switch is a protection technique in an optical transmission device using an optical fiber, and is a detour transmission path when an operation path failure occurs with respect to N optical transmission paths (operation paths) normally operated by the optical transmission apparatus. It functions as a (redundant path) (see, for example, Patent Document 1).

  The operation path transmits an optical signal through an optical fiber. The transmission side of this working path has a 1: 2 coupler, and the reception side has a 2: 1 coupler. The 1: 2 coupler demultiplexes the optical signal transmitted from the transmission path into two, transmits one optical signal to the 2: 1 coupler, and transmits the other optical signal to the transmission switch part of the protection switch. Yes. The 2: 1 coupler combines the optical signal transmitted from the 1: 2 coupler and the optical signal transmitted from the reception switch unit connected to the transmission switch unit, and transmits the resultant signal to the transmission path.

  The transmission switch unit is composed of a plurality of optical switches, and each optical switch has a redundant port for connection to the selected 1: 2 coupler. The reception switch unit is composed of a plurality of optical switches, and each optical switch has a redundant port for connection to the selected 2: 1 coupler. Note that the optical switch of the reception switch unit has an empty port for cutting the redundant path in addition to the redundant port.

  Here, when a failure occurs in one of the working paths, the transmission switch unit selects a redundant port corresponding to the working path in which the failure has occurred and connects it to the 1: 2 coupler of this working path. Further, the reception switch unit selects a redundant port corresponding to the active path where the failure has occurred and connects it to the 2: 1 coupler of this active path.

  Thus, when a failure occurs in one of the operation paths, the transmission switch unit and the reception switch unit are connected to the transmission side 1: 2 coupler and the reception side 2: 1 coupler of the operation path in which the failure has occurred. As a result, a transmission path can be secured and the optical signal can be transmitted by detouring with a redundant path. Thus, since one redundant path is shared by N operation paths, it is called an N + 1 protection switch.

  When the operation path is operating normally, the optical switch of the reception switch unit is connected to an empty port, the redundant path is cut off, and the optical signal is cut off. This is because, when the optical signal from the redundant path is transmitted to the operation path in a normal state, the signal deteriorates by overlapping with the signal of the operation path. Therefore, the optical switch of the reception switch unit is held in a state where the redundant path is disconnected until a failure occurs in the transmission path.

Japanese Patent No. 2853750 JP 2002-291002 A

  Here, in the conventional protection switch disclosed in Patent Document 1, when the optical switch of the transmission switch unit or the reception switch unit fails, the redundant path remains disconnected or the path cannot be switched. Become. However, this optical switch failure has a problem that it is not discovered until a failure occurs in the operation path and the redundant path is switched, and a method for confirming the normality of the redundant path is not provided.

  In addition, there is a technique for verifying the operation of an optical switch in a conventional protection switch (see, for example, Patent Document 2), but a method for confirming a redundant path without affecting the operation path during normal operation is not provided. There was a problem.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a protection switch capable of confirming normal operation of a redundant path during normal operation.

  The protection switch according to the present invention includes a redundant switch connected to the transmission side of the operation path, a transmission switch unit having an empty port, a redundancy port connected to the reception side of the operation path, and an optical signal output by itself. It has a monitor port for measurement, and controls the connection switching operation to the reception switch unit that receives the optical signal from the transmission switch, the empty port of the transmission switch unit and the monitor port of the reception switch unit, and for monitoring A switch control / monitor monitoring unit that monitors the optical signal measured through the port and confirms the normality of the transmission switch unit is provided.

  According to the present invention, since it is configured as described above, the redundancy path is connected to the measuring device, and the optical signal of the redundancy path is measured, so that the normality of the redundancy path can be improved before the operation path becomes abnormal. This can be confirmed, and it is possible to prevent a double failure that the protection does not operate normally when a failure occurs.

It is a figure which shows the structure of the protection switch which concerns on Embodiment 1 of this invention. It is a flowchart which shows operation | movement of the protection switch which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the protection switch which concerns on Embodiment 2 of this invention. It is a flowchart which shows operation | movement of the protection switch which concerns on Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a protection switch according to Embodiment 1 of the present invention.
The protection switch functions as a redundant path (transmission path) that forms a detour when a failure occurs in any of a plurality of operation paths (transmission paths) that are normally operated in the optical transmission apparatus. Here, the operation path includes a 1: 2 coupler 1 and a 2: 1 coupler 2. FIG. 1 shows a case where protection switches are provided for the six operation paths a to f.

  The 1: 2 coupler 1 demultiplexes the optical signal transmitted from the transmission side of the operation path into two, and is connected to the transmission side of each operation path. One optical signal demultiplexed by the 1: 2 coupler 1 is transmitted to a 2: 1 coupler 2 provided on the receiving side of the corresponding operation path, and the other optical signal is a transmission switch unit 3 described later of the protection switch. Is transmitted.

  The 2: 1 coupler 2 multiplexes the optical signal transmitted from the corresponding 1: 2 coupler 1 and the optical signal transmitted from the receiving switch unit 4 (to be described later) of the protection switch. Connected to the receiver. The optical signal combined by the 2: 1 coupler 2 is transmitted to the reception side of the operation path.

  As shown in FIG. 1, the protection switch connected to the operation path configured as described above and functioning as a redundant path includes a transmission switch unit 3, a reception switch unit 4, a power monitor (measuring instrument) 5, and switch control / The monitor monitoring unit 6 is configured.

The transmission switch unit 3 connects to the 1: 2 coupler 1 provided in the failed operation path when a failure occurs in any of the operation paths, and connects the 1: 2 coupler 1 from the transmission side of the operation path. The optical signal transmitted via the signal is transmitted to the reception switch unit 4.
The transmission switch unit 3 includes a plurality of optical switches 11 to 13 having redundant ports for connection with the 1: 2 coupler 1 selected by the switch control / monitor monitoring unit 6, and the switch control / monitor monitoring unit 6. And an optical switch 14 having a redundant port for connecting to the selected optical switches 11 to 13. Each of the optical switches 11 to 13 has one vacant port for cutting the redundant path in addition to the redundant port.

The reception switch unit 4 is connected to the 2: 1 coupler 2 provided in the failed operation path when a failure occurs in any of the operation paths, and the optical signal transmitted from the transmission switch unit 3 is 2 1: Transmitted to the receiving side of the operation path via the coupler 2.
The reception switch unit 4 includes a plurality of optical switches 16 to 18 having redundant ports for connection to the 2: 1 coupler 2 selected by the switch control / monitor monitoring unit 6, and the switch control / monitor monitoring unit 6. An optical switch 15 having a redundant port for connecting to the selected optical switches 16 to 18 is provided. Each of the optical switches 16 to 18 has one monitor port for connecting to the power monitor 5 in addition to the redundant port.

The power monitor 5 measures the optical signal transmitted from the reception switch unit 4.
The switch control / monitor monitoring unit 6 monitors the function of controlling the connection switching operation of the optical switches 11 to 18 of the transmission switch unit 3 and the reception switch unit 4 and the measured value of the optical signal measured by the power monitor 5. It has a function.

Next, the operation of the protection switch configured as described above will be described. FIG. 2 is a flowchart showing the operation of the protection switch according to Embodiment 1 of the present invention. Hereinafter, the normality confirmation operation of the redundant path corresponding to the working path a will be described.
In the normality confirmation operation by the protection switch, as shown in FIG. 2, first, the transmission switch unit 3 and the reception switch unit 4 connect the redundant path corresponding to the operation path a to the power monitor 5 (step ST21). That is, the transmission switch unit 3 connects the optical switch 11 to the redundant port (for connecting to the 1: 2 coupler 1 of the operation path a) according to the control by the switch control / monitor monitoring unit 6, and the optical switch 14 is connected to the redundant port (for connecting to the optical switch 11) in the upper stage. Further, the optical switch 15 of the reception switch unit 4 is connected to the upper redundant port (for connecting to the optical switch 16), and the optical switch 16 is connected to the lower monitoring port.

  By connecting the optical switches in this way, the optical signal demultiplexed by the 1: 2 coupler 1 of the operation path a passes through the optical switch 11, the optical switch 14, the optical switch 15, and the optical switch 16. A path to be input to the power monitor 5 is established. Here, when the optical signal from this path is normally measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the redundant path corresponding to the operation path a is normal (step ST22).

  Next, the connection switching of the transmission switch unit 3 is confirmed by switching the connection of the optical switches 11 to 14 of the transmission switch unit 3 (steps ST23 and ST24). First, when the optical switch 11 is connected to the lower empty port from the state in which the redundant path is connected to the power monitor 5, the path to the power monitor 5 is disconnected. Here, when the optical signal is not measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switch 11 has been switched normally.

  Next, the optical switch 11 is returned to the upper redundant port, the optical switch 12 is connected to the lower empty port, the optical switch 13 is connected to the lower empty port, and the optical switch 14 is connected to the intermediate or lower optical switch 12 or the optical switch 13. The path to the power monitor 5 is cut off even if each is connected to a redundant port. Here, when the optical signal is not measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switches 12 to 14 are normally connected and switched.

  Similarly, the connection switching operation of each of the optical switches 11 to 18 is controlled, and redundant signals corresponding to the remaining operation paths b to f are connected to the power monitor 5 to measure the optical signals. Therefore, the normality of the connection switching operation of the optical switches 11 to 14 of the transmission switch unit 3 can be confirmed.

  In addition, in this redundancy path normality confirmation operation, if the connection switching operation of each of the optical switches 11 to 18 is mistakenly controlled, an erroneous optical signal is transmitted to the operation path. In order to prevent this, control for the connection switching operation of the optical switches 11 to 18 is programmed in advance in the switch control / monitor monitoring unit 6 so that erroneous control is not performed during the normality confirmation operation.

  As described above, according to the first embodiment, the monitor switches are provided with empty ports in the optical switches 11 to 13 of the transmission switch unit 3 and connected to the power monitor 5 in the optical switches 16 to 18 of the reception switch unit 4. And the normality confirmation for each redundant path is performed, so that the normality of the redundant path can be confirmed before a failure occurs in the operation path, and the optical switches 11 to 11 of the transmission switch unit 3 can be confirmed. The normality of the 14 connection switching operations can be confirmed, and when a failure occurs in the operation path, a double failure that the protection does not operate normally can be prevented.

Embodiment 2. FIG.
In the first embodiment, the redundant path is connected to the power monitor 5 and the normality of the redundant path and the normality of the connection switching operation of the transmission switch unit 3 are confirmed. 2 confirms the normality of the connection switching operation of the reception switch unit 4 in addition to this.
FIG. 3 is a diagram showing a configuration of a protection switch according to Embodiment 2 of the present invention.
The protection switch according to Embodiment 2 shown in FIG. 3 is obtained by changing the optical switches 16 to 18 of the protection switch according to Embodiment 1 shown in FIG. 1 to optical switches 21 to 23, and the other configurations are the same. Therefore, the description thereof is omitted.

  As shown in FIG. 3, the optical switches 21 to 23 provide a redundant path in addition to a redundant port for connecting to the selected 2: 1 coupler 2 and a monitor port for connecting to the power monitor 5. One free port for disconnecting is provided.

Next, the operation of the protection switch configured as described above will be described. FIG. 4 is a flowchart showing the operation of the protection switch according to Embodiment 2 of the present invention. Hereinafter, the normal operation of the redundant path corresponding to the working path a will be described.
In the normality confirmation operation by the protection switch, as shown in FIG. 4, first, the transmission switch unit 3 and the reception switch unit 4 connect the redundant path corresponding to the operation path a to the power monitor 5 (step ST41). That is, the transmission switch unit 3 connects the optical switch 11 to the redundant port (for connecting to the 1: 2 coupler 1 of the operation path a) according to the control by the switch control / monitor monitoring unit 6, and the optical switch 12 and the optical switch 13 are connected to the lower empty port, and the optical switch 14 is connected to the upper redundant port (for connecting to the optical switch 11). Further, the optical switch 15 of the reception switch unit 4 is connected to the upper redundant port (for connection with the optical switch 21), the optical switch 21 is connected to the third monitoring port, and the optical switch 22 and the optical switch The switch 23 is connected to the fourth-stage empty port.

  By connecting the optical switches in this way, the optical signal demultiplexed by the 1: 2 coupler 1 of the operation path a passes through the optical switch 11, the optical switch 14, the optical switch 15, and the optical switch 21. A path to be input to the power monitor 5 is established. Here, when the optical signal from this path is normally measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the redundant path corresponding to the operation path a is normal (step ST42).

  Next, normality of the connection switching operation of the transmission switch unit 3 and the reception switch unit 4 is confirmed by performing connection switching of the optical switches 11, 14, 15, and 21 using this connection state as a basic state (steps ST43 to ST46). ).

  First, when the optical switch 11 is repeatedly switched from the basic state to the lower vacant port and the upper redundant port, the optical signal from the operation path a is repeatedly cut off and conducted. Here, when the presence / absence of an optical signal is repeatedly measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switch 11 is normally connected and switched.

  Next, when the optical switch 14 is repeatedly switched from the basic state to a redundant port other than the upper stage and the upper redundant port, the optical signal from the operation path a is repeatedly cut off and conducted. Here, when the presence / absence of an optical signal is repeatedly measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switch 14 is normally switched.

  Next, when the optical switch 15 is repeatedly switched from the basic state to a redundant port other than the upper stage and the upper redundant port, the optical signal from the operation path a is repeatedly cut off and conducted. Here, when the presence / absence of an optical signal is repeatedly measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switch 15 has been normally connected and switched.

  Next, when the optical switch 21 is repeatedly switched from the basic state to the fourth-stage empty port and the third-stage monitoring port, the optical signal from the operation path a is repeatedly cut off and conducted. Here, when the presence / absence of an optical signal is repeatedly measured by the power monitor 5, the switch control / monitor monitoring unit 6 determines that the optical switch 21 has been normally connected and switched.

  In the same manner, the connection switching operation of each of the optical switches 11 to 15 and 21 to 23 is controlled, and the redundant path corresponding to the remaining operation paths b to f is connected to the power monitor 5 to measure the optical signal. Therefore, the normality of all redundant paths can be confirmed, and the normality of the connection switching operation of all the optical switches 11 to 15 and 21 to 23 of the transmission switch unit 3 and the reception switch unit 4 can be confirmed. it can.

  In addition, in this redundancy path normality confirmation operation, if control of the connection switching operation of each of the optical switches 11 to 15 and 21 to 23 is mistaken, an erroneous signal is transmitted to the operation path. In order to prevent this, the control of the connection switching operation of the optical switches 11 to 15 and 21 to 23 is programmed in advance in the switch control / monitor monitoring unit 6 so that erroneous control is not performed during normality confirmation. To do.

  As described above, according to the second embodiment, since the optical switches 21 to 23 of the reception switch unit 4 are further provided with empty ports to check the normality for each redundant path, the first embodiment is provided. In addition to the effects in the above, the normality of the connection switching operation of all the optical switches 11 to 15 and 21 to 23 of the transmission switch unit 3 and the reception switch unit 4 can be confirmed, and when a failure occurs in the operation path A double failure that the protection does not work properly can be prevented.

Embodiment 3 FIG.
In the first and second embodiments, the power monitor 5 is provided inside the apparatus. However, the power monitor 5 may not be provided in the apparatus, and only the monitor port may be provided in the reception switch unit 4. In this case, a measuring instrument such as a power meter connected to the monitor port is installed outside to check the normality of the redundant path and the normality of the connection switching operation of each optical switch of the transmission switch 3 and the reception switch 4. That's fine. By configuring in this way, the power monitor 5 can be omitted, and parts can be reduced.

  1 1: 2 coupler, 2 2: 1 coupler, 3 transmission switch section, 4 reception switch section, 5 power monitor (measuring instrument), 6 switch control / monitor monitoring section, 11-18, 21-23 optical switch.

Claims (5)

In a protection switch that is connected to an operation path that transmits an optical signal between optical transmission devices and functions as a redundant path for the operation path,
A redundant switch connected to the transmission side of the operational path, and a transmission switch unit having an empty port;
A redundancy switch connected to the reception side of the operational path, and a monitor port for measuring an optical signal output by the reception path, and a reception switch unit for receiving an optical signal from the transmission switch;
Controls the connection switching operation to the empty port of the transmission switch unit and the monitor port of the reception switch unit, monitors the optical signal measured through the monitor port, and confirms the normality of the transmission switch unit A protection switch, comprising: a switch control / monitor monitoring unit for performing the protection. In a protection switch that is connected to an operation path that transmits an optical signal between optical transmission devices and functions as a redundant path for the operation path,
A redundant switch connected to the transmission side of the operational path, and a transmission switch unit having an empty port;
A redundancy switch connected to the reception side of the operational path, and a monitor port; a reception switch unit that receives an optical signal from the transmission switch;
A measuring instrument for measuring an optical signal from the reception switch unit via the monitoring port;
Switch control / monitor monitoring unit for controlling connection switching operation of the vacant port of the transmission switch unit and the monitoring port of the reception switch unit, monitoring the measurement result by the measuring instrument, and confirming the normality of the transmission switch unit And a protection switch. The protection switch according to claim 2, wherein the measuring device is a power monitor. The reception switch unit further includes an empty port,
The switch control / monitor monitoring unit controls connection switching operation to an empty port of the reception switch unit, and confirms normality of the transmission switch unit and the reception switch unit. 4. The protection switch according to any one of items 3. The protection switch according to any one of claims 1 to 4, wherein a connection switching operation of the transmission switch unit and the reception switch unit in the switch control / monitor monitoring unit is programmed in advance.

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