JP2008244024A - Maintaining system of laser output break alarm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that when an optical network is constituted of a redundant structure and output disconnection caused by a failure of a laser occurs in an active system and switching to a standby system is carried out, a laser output disconnection alarm is masked in order to stop a laser output in the active system, therefore it becomes difficult to specify by what alarm the active system is switched to the standby system or a failed location. <P>SOLUTION: This maintenance system of a laser output disconnection alarm comprises a switching control circuit for carrying out output control in either the active system or the standby system according to an alarm factor including the laser output disconnection in the active system and the standby system lasers, an active system laser output disconnection detecting circuit for monitoring the output power of the active system laser and detecting the laser output disconnection, a standby system laser output disconnection detecting circuit for monitoring the output power of the standby system laser and detecting the laser output disconnection, an active system alarm maintaining circuit for maintaining the active system laser output disconnection alarm based on the active system laser output disconnection alarm and a system selection situation, and a standby system alarm maintaining circuit for maintaining the standby system laser output disconnection alarm based on the standby system laser output disconnection alarm and the system selection situation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical network, and more particularly, to a problem when an active / standby switch occurs due to a laser output interruption alarm when an optical network is built in a redundant configuration, and an improvement method thereof. is there.

  Conventionally, in an optical transmission device, if the laser output power drops significantly due to a laser failure, a laser output interruption alarm is generated. If the laser output is stopped by output stop control, the power of The secondary laser output cutoff alarm that occurs due to the drop is masked as an unnecessary alarm.

  Here, when an optical network is built in a redundant configuration, and an output interruption occurs due to a laser failure in the active system and the system is switched to the standby system, the laser output interruption alarm is masked to stop the laser output of the active system. End up. As a result, there is no history of what alarm was switched from the active system to the standby system, and as a result, it becomes difficult to identify the failure location.

  The following are proposed as prior arts of this type of optical network constructed in a redundant configuration.

  In JP-A-6-120967 cited as a first conventional example (Patent Document 1), a left loop is used as an active system, a right loop is used as a standby system, and is connected to the left loop. When the laser of the light transmitter becomes abnormal and the light output decreases, the automatic light output power controller that monitors the laser emission detects this abnormality and sends alarm information to the monitoring controller via the monitoring controller interface unit. Outputting is disclosed. However, it is not described that the alarm information is retained.

  Next, in the invention disclosed in Japanese Patent Laid-Open No. 11-177468, which is cited as a second conventional example (Patent Document 2), the standby transmitter / receiver is powered on by active / preliminary switching because the standby transmitter / receiver is powered off. In addition, if the failed transmitter / receiver is reset after an alarm is activated by power-on, the active / standby switching will occur and this transmitter / receiver will become a standby, which will delay the discovery of the failure. In order to achieve this purpose, the switching signal generator periodically powers all the transceivers by periodically switching the transceivers. When an alarm occurs, the status monitoring and control signal generator receives the status report signal from the transceiver and acknowledges the alarm content. And, if the alarm caused by the power-on without resetting is to hold the alarm.

However, a specific configuration or method is not disclosed. Moreover, this second conventional example is not a case where a failure occurs during operation of the active and standby transceivers, but tests whether or not the active and standby transceivers are operated normally by switching them regularly. Technology.
JP-A-6-120967 JP-A-11-177468

  The present invention has been made in order to solve the above-mentioned problems inherent in the prior art in view of the above-described actual situation. Therefore, the object of the present invention is to provide a backup bus for the working bus and a spare because a laser output interruption alarm has occurred. When the laser output of the bus that caused the alarm is stopped due to the switching of the bus, the alarm is kept valid even after the laser output disconnection alarm is not output, so that the switching factor at the time of switching is It is an object of the present invention to provide a laser output cutoff alarm holding means and a system thereof capable of appropriately determining that the laser output is cutoff.

  In order to achieve the above object, a laser output interruption alarm holding system according to the present invention includes a first bus and a second bus, a first laser connected to the first bus and transmitting an optical signal, A second laser connected to the second bus for transmitting an optical signal, an alarm factor including a laser output interruption of the first and second lasers, or manual selection of the first system and the second system A switching control circuit for controlling the output of one of the first system and the second system and controlling the output stop of the other, and a first laser for monitoring the output power of the first laser and detecting a laser output interruption From the output interruption detection circuit, the second laser output interruption detection circuit that monitors the output power of the second laser to detect the laser output interruption, the first laser output interruption alarm, and the system selection status, the first The laser output cutoff alarm that holds And a second alarm holding circuit for holding the second laser output cutoff alarm from the second laser output cutoff alarm and the system selection status, and the first and second alarm holdings The output of the circuit is achieved by a laser power off alarm retention system coupled to the switching control circuit.

  The present invention is configured and operates as described above. According to the present invention, the following effects can be obtained.

  That is, in the present invention, when the optical network is constructed in a redundant configuration, when the switching between the active system and the standby system occurs due to the occurrence of the laser output interruption alarm, the switching is realized by the laser output interruption alarm. It becomes possible to specify accurately.

  Next, the best mode for carrying out the present invention will be specifically described based on examples.

  FIG. 1 is a block diagram showing an embodiment of the present invention.

  In the present invention, by providing a circuit for holding a laser output cutoff alarm, the laser output cutoff alarm is held even after the active system and the standby system are switched.

  Referring to FIG. 1, the system according to the present invention outputs either the active system or the standby system depending on the active bus 1 and the standby system bus 2, alarm factors including the laser output disconnection, or manual selection of the active system and the standby system. Switch control circuit 3 for controlling and stopping the output of the other, lasers 4 and 5 for converting electrical signals to optical signals and transmitting optical signals, laser output for monitoring laser output power and detecting laser output interruption alarms The disconnection detection circuits 6 and 7 and the laser output disconnection alarm and the alarm holding circuits 8 and 9 for retaining the laser output disconnection alarm based on the system selection status are included. Reference numeral 13 denotes another switching factor or a manual switching control signal that is input to the switching control circuit 3 as necessary, for example, to perform a current or standby switching operation that is periodically executed.

  In the conventional configuration, when the laser 4 breaks down and the output power decreases while the active bus 1 is selected, the laser output disconnection detection circuit 6 notifies the laser output disconnection alarm directly to the switching control circuit 3 for notification. In response to this, the switching control circuit 3 controls the output of the laser 5 and controls the output of the laser 4 to stop the switching to the standby bus 2. In order to stop the output of the laser 4, the laser output cutoff detection circuit 6 masks the laser output cutoff alarm. Therefore, since the laser output disconnection alarm of the laser output disconnection detection circuit 6 disappears, it is impossible to know what alarm is generated and the switching control is performed.

  As a method for solving this problem, in the present invention, when the laser 4 fails and the output power decreases while the active bus 1 is selected, the laser output disconnection detection circuit 6 holds a laser output disconnection alarm as an alarm. The circuit 8 is notified, and the alarm holding circuit 8 notifies the switching control circuit 3. Upon receiving the notification, the switching control circuit 3 controls the output of the laser 5 and performs the output stop control of the laser 4 in order to perform switching control to the standby bus 2. At the same time, the switching control circuit 3 notifies the alarm holding circuits 8 and 9 that the active bus 1 has been deselected and the standby bus 2 has been selected. When the active bus 1 is deselected and the output of the laser 4 is controlled to be stopped, the laser output interruption alarm is masked as an unnecessary alarm. The alarm holding circuit 8 is not notified because the laser output cutoff alarm is masked, but determines that the laser output cutoff alarm is not notified because the laser 4 is controlled to stop the output, and holds the laser output cutoff alarm. With this configuration, it is possible to determine which alarm is used for switching control.

  Next, the operation of one example of the embodiment according to the present invention will be described.

  2 shows an input / output terminal diagram of the alarm holding circuits 8 and 9, FIG. 3 shows an operation flowchart of the alarm holding circuits 8 and 9, and FIGS. 4 and 5 show operation time charts of the alarm holding circuits 8 and 9, respectively.

  FIG. 2 is an input / output terminal diagram of the alarm holding circuits 8 and 9. Since the alarm holding circuits 8 and 9 have the same configuration, for convenience of explanation, the alarm holding circuits 8 and 9 are described in common in only one figure of FIG. The alarm holding circuits 8 and 9 have two outputs, a laser output interruption alarm 10 input to the input terminal 10a and a switching control 11 input to the input terminal 11a, and an alarm output output from the output terminal 12a. 12.

  FIG. 3 is an operation flowchart of the alarm holding circuits 8 and 9.

  Referring to FIG. 3, the laser output interruption alarm 10 is input to the input terminal 10a of the alarm holding circuit 8 or 9 in step S11. Next, in step S12, it is determined whether or not the input of the switching control 11 from the switching control circuit 3 has changed from “1” system selection to “0” system selection. If “YES” as a result of the determination in step S12, “1” is continuously output as the alarm output 12 from the output terminal 12a of the alarm holding circuit 8 or 9 to the switching control circuit 3 in step S13. If “NO” as a result of the determination in step S12, the alarm output 12 outputs the input value of the laser output cutoff alarm 10 as it is, as shown in step S15.

  As described above, when the input of the switching control 11 of the switching control circuit 3 is changed from “1” system selection to “1” system non-selection as a result of the determination in step S12, the alarm holding circuit 8 is displayed as shown in step S13. Alternatively, the alarm output 12 ("1") is continuously output from 9, but maintenance processing such as maintenance and inspection is executed in step S14 by holding this output. The alarm output “1” is erased, that is, reset after a lapse of a predetermined time after the maintenance process is completed. When the alarm output “1” is deleted in step S14, the process returns to step S11.

  In this way, whether or not the output of the alarm output 12 is maintained depending on whether or not the switching control 11 changes from “1” system selection to “0” system selection after “1” is input from the laser output interruption alarm 10. It is divided into whether the value of the laser output interruption alarm 10 is output as it is.

  4 shows that when “1” (alarm state) is input from the laser output cutoff alarm 10, the switching control 11 selects the “1” (or “0”) system (the “1” system selection in the figure). This is a time chart when changing from “0” (or “1”) to system selection. In this case, the alarm output 12 of the “1” system continues to hold the alarm state output from the laser output interruption alarm 10.

  FIG. 5 is a time chart when the switching control 11 does not change the selected system from the “1” system selection when “1” (alarm state) is input from the laser output interruption alarm 10. In this case, the “1” system alarm output 12 outputs the alarm signal of the laser output interruption alarm 10 as it is.

  The alarm output 12 outputs the value of the laser output interruption alarm 10 as it is. After that, when the switching control 11 becomes “0” system selection, “1” cannot be input from the laser output disconnection alarm 10.

  The present invention can be used for an optical network device and a device having a redundant configuration such as UPSR and BLSR.

It is a block block diagram which shows one Example of this invention. It is an input / output terminal diagram of an alarm holding circuit. It is an operation | movement flowchart of an alarm holding circuit. It is a time chart when the switching control changes from “1” system selection to “1” system non-selection after “1” is input from the laser output cutoff alarm. It is a time chart when the switching control does not change with the “1” system selected when “1” is input from the laser output cutoff alarm.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Current system bus 2 ... Backup system bus 3 ... Switching control circuit 4, 5 ... Laser 6, 7 ... Laser output disconnection detection circuit
8, 9 ... Alarm holding circuit 10 ... Laser output disconnection alarm 11 ... Switching control 12 ... Alarm output 13 ... Other switching factors or manual switching control

Claims (5)

A first bus and a second bus;
A first laser connected to the first bus for transmitting an optical signal and a second laser connected to the second bus for transmitting an optical signal;
The output control of one of the first system or the second system is controlled by an alarm factor including the laser output interruption of the first or second laser or by manually selecting the first system or the second system, and the other is controlled. A switching control circuit for controlling output stop;
A first laser output cutoff detection circuit that monitors output power of the first laser to detect laser output cutoff and a second laser output that detects laser output cutoff by monitoring the output power of the second laser. Disconnection detection circuit;
A first alarm holding circuit that holds the first laser output interruption alarm from the first laser output interruption alarm and the system selection situation, and the second laser output from the second laser output interruption alarm and the system selection situation. A second alarm holding circuit for holding a break alarm;
The outputs of the first and second alarm holding circuits are coupled to the switching control circuit,
Laser output disconnection alarm retention system characterized by that.   The first alarm holding circuit includes a first input terminal that receives the output of the first laser output break detection circuit, and a second input terminal that receives a switching control signal from the switching control circuit. The laser output disconnection alarm holding system according to claim 1, further comprising a first output terminal for outputting an alarm output to the switching control circuit.   The second alarm holding circuit includes a third input terminal that receives the output of the second laser output break detection circuit, a fourth input terminal that receives a switching control signal from the switching control circuit, and 2. The apparatus according to claim 1, further comprising: a second output terminal that outputs an alarm output to the switching control circuit, and further comprising a hardware configuration substantially similar to the first alarm holding circuit. Laser output cutoff alarm retention system.   In the first alarm holding circuit, a laser output interruption alarm is inputted from the first laser output interruption detection circuit to the first input terminal, and a switching control signal is inputted to the second input terminal. When the “1” system selection changes to “1” system non-selection, the alarm output continues to be output from the first output terminal, and the “1” system selection does not change to the “1” system non-selection. 3. The laser output interruption alarm holding system according to claim 2, wherein the laser output interruption alarm input value is inputted as it is from the first output terminal to the first input terminal as it is.   In the second alarm holding circuit, a laser output cutoff alarm is inputted from the second laser output cutoff detection circuit to the third input terminal, and a switching control signal is inputted to the fourth input terminal. When the “1” system selection is changed to “1” system non-selection, the alarm output is continuously output from the second output terminal, and the “1” system selection is not changed to “1” system non-selection. 4. The laser output interruption alarm holding system according to claim 3, further comprising outputting the laser output interruption alarm input value inputted from the second output terminal to the third input terminal as it is.

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