JP2001326590A - Redundancy changeover system for optical transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a definite redundancy changeover system for an optical transmitter that has optical transmission panels for an active system and a standby system and has redundancy. SOLUTION: A setting circuit 9 that collects and sets states of the optical transmission panels 1, 2 and a timing circuit 10 that supplies a timing signal to activate setting information given by this setting circuit 9 in prescribed timing are added to the optical transmitter. The setting circuit 9 detects the state of the optical transmission panels 1, 2 and produces a changeover procedure signal (changeover code) for a prescribed operation to instruct the operation to each of the optical transmission panels 1, 2, alarm inhibit circuits 5, 6, alarm memory circuits 7, 8, a changeover control circuit 4 and a power supply circuit 11 for the changeover operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a redundant switching system, and more particularly, when a failure occurs in a plurality of redundantly configured optical transmission boards of an optical transmission apparatus, the working system is switched to a standby system to improve the reliability of the system. The present invention relates to a redundant switching system for an optical transmission device.

[0002]

2. Description of the Related Art A prior art of such a redundant switching system is disclosed in, for example, Japanese Patent Application Laid-Open No. 1-69126, entitled "Redundant Switching System for an Apparatus Taking a Cold Standby". FIG.
FIG. 2 is a block diagram showing a configuration of an optical transmission device having a redundant configuration. This optical transmission device includes a pair of optical transmission boards 1 and 2, an optical combiner 3, and a switching control circuit 4 for controlling switching of the pair of optical transmission boards 1 and 2. The outputs of the optical transmitter 1 and the optical transmitter 2 are connected to an optical multiplexer 3. The optical multiplexer 3 outputs an output signal when any one of the optical transmitters 1 and 2 receives an optical signal. The optical transmission boards 1 and 2 are in a cold standby state, and are controlled by the switching control circuit 4 so that the two optical transmission boards 1 and 2 do not operate at the same time. Switching between the optical transmission boards 1 and 2 is performed by outputting an optical output interruption alarm from the optical transmission boards 1 and 2 to the switching control circuit 4. Therefore, when the optical transmission board 1 is used as an active system and an optical output interruption alarm is issued from the optical transmission board 1, the switching control circuit 4 switches the working system to the optical transmission board 2. Here, the light output interruption alarm is output when the output is stopped, and is always output from the cold standby optical transmission panel due to its nature. Therefore, for example, in order to switch from the optical transmission board 1 to the optical transmission board 2, the optical output disconnection alarm output from the optical transmission board 2 which is in a cold standby state is ignored, and the optical transmission board 2 is normally operated. Treat it as a standby state. On the other hand, after switching from the optical transmission board 1 to the optical transmission board 2, an optical output interruption alarm is continuously output from the optical transmission board 1.

However, the optical output disconnection alarm output from the optical transmission board 1 is ignored because it cannot be distinguished whether it is an alarm output in the working state or an alarm generated because the standby state is set after switching. There was a problem that it was not possible. That is, automatic switching from the optical transmission board 1 to the optical transmission board 2 is possible, but after switching from the optical transmission board 1 to the optical transmission board 2, the optical output disconnection alarm is continuously output from the optical transmission board 1. Is done. For this reason, the automatic switching from the optical transmission board 2 to the optical transmission board 1 cannot be performed, and the optical transmission board 1 is dedicated to the current use and the optical transmission board 2 is dedicated to the spare.

[0004] Next, in order to solve the above-mentioned problems of the prior art, a technique shown in FIG. 13 has been proposed. That is, alarm prohibition circuits 5 and 6 and alarm memory circuits 7 and 8 are added between the optical transmitters 1 and 2 and the switching control circuit 4, respectively. These alarm prohibition circuits 5 and 6 prevent the active system and the standby system from taking in the cold standby side light output interruption alarm. Also, the alarm memory circuits 7 and 8
Stores the optical output disconnection alarm output during use. FIG.
In the circuit shown in FIG. 3, the optical transmission board 1 and the optical transmission board 2 take a cold standby with each other, and are controlled by the switching control circuit 4 so that only one of the optical transmission boards is turned on. The output is obtained. The redundant switching of the optical transmission boards 1 and 2 is performed using an optical output disconnection alarm output from the optical transmission boards.

When the optical transmission board 1 is on, the alarm prohibition circuit 5
The ban has been lifted. However, when an optical output interruption alarm is output from the optical transmitter 1, the alarm is stored in the alarm memory circuit 7. On the other hand, the optical output interruption alarm output from the optical transmission board 2 in the cold standby state is inhibited by the alarm inhibition circuit 6. The alarm memory circuit 8 does not store an optical output disconnection alarm. Therefore, when an optical output disconnection alarm is output from the optical transmitter 1, the switch to the optical transmitter 2 is performed. At this time, the optical output disconnection alarm of the optical transmitter 1 is stored in the alarm memory circuit 7. From this, it can be seen that the optical transmission board 1 has been switched to the optical transmission board 2 because of a failure.

Then, when the failure of the optical transmitter 1 is repaired,
The contents stored in the alarm memory circuit 7 are deleted. Then, the optical output disconnection alarm from the optical transmission board 1 is prohibited by the alarm prohibition circuit 5, and the optical transmission board 1 enters the cold standby state.
In this way, if the optical transmission board 2 subsequently has a failure, it is automatically switched to the optical transmission board 1 as described above. If the optical transmitter 1 is switched to the optical transmitter 2 by forced switching from the outside without outputting the optical output interruption alarm from the optical transmitter 1, the alarm is prohibited by the alarm prohibiting circuit 5, so that the alarm memory circuit 7 is not stored. Therefore, even when the optical transmission board 2 is turned on, the optical transmission board 1 is in a non-alarm state, so that the optical transmission board 1 is in a cold standby state.

[0007]

However, the problem with the prior art shown in FIG.
Can be automatically switched, but after switching from the optical transmission board 1 to the optical transmission board 2, the optical transmission board 1 continuously outputs an optical output disconnection alarm. For this reason, automatic switching and switching back from the optical transmission board 2 to the optical transmission board 1 cannot be performed, and the optical transmission board 1 is used exclusively for the current use.
The optical transmission board 2 was exclusively used for spare.

On the other hand, in the prior art shown in FIG. 13, in order to solve the above-mentioned problems of the prior art, the prohibition circuits 5 and 6 for not taking in the optical output cutoff alarm on the cold standby side and the output during active use are provided. And memory circuits 7 and 8 for storing the cut-off light output alarm. The switching control circuit 4 determines whether or not the optical transmitter 1 and the optical transmitter 2 output the optical output interruption alarm.
Switching is realized by performing control for taking in the data.
As a problem of the prior art shown in FIG. 13, control of an alarm prohibition circuit and an alarm memory circuit, taking in and canceling the presence or absence of an optical output cutoff alarm output from the optical transmitter 1 and the optical transmitter 2, switching timing of a switching control circuit, Descriptions of functional operations related to power supply / release and transition to the cold standby state are insufficient or missing, and circuit operations that cannot be supplemented only by the operations of the alarm inhibition circuit and the memory circuit are required.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to clarify the switching function and operation of an optical transmission apparatus having a function of performing redundant switching of an optical transmission board using an optical output interruption alarm output from the optical transmission board. It is an object of the present invention to provide a redundant switching system for an optical transmitting apparatus.

[0010]

According to the present invention, there is provided a redundant switching system for an optical transmitting apparatus, wherein an optical multiplexer for receiving optical outputs from a plurality of optical transmitting boards and the optical transmitting boards are selectively used as a working system or a standby system. A switching control circuit to be operated, an alarm inhibiting circuit and an alarm memory circuit connected between the switching control circuit and the optical transmission board, and a setting circuit for collecting and setting the state of the optical transmission board; And a timing circuit for supplying a timing signal for operating the switching control circuit, the alarm inhibition circuit, and the alarm memory circuit based on the setting information provided by the setting circuit.

According to a preferred embodiment of the redundant switching system of the optical transmission device according to the present invention, the setting circuit encodes a predetermined disconnection procedure signal based on the optical output disconnection information transmitted from the optical transmission board. The alarm prohibition circuit and the alarm memory circuit include a decoding unit for decoding the code sent from the setting circuit and a setting / cancellation unit for setting and canceling the state. Further, a forced switching signal for performing forced switching is input to the setting circuit irrespective of the optical output disconnection information output from the optical transmission board. Controlled by a switching control signal from a switching control circuit,
A power supply circuit for supplying an operating voltage to the plurality of optical transmission boards is provided.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration and operation of a preferred embodiment of a redundant switching system for an optical transmitter according to the present invention will be described below with reference to the accompanying drawings. Note that, for convenience, the same reference numerals are used for components corresponding to the above-described components.

FIG. 1 is a block diagram showing a configuration of a preferred embodiment of a redundant switching system of an optical transmitting apparatus according to the present invention. The redundant switching system of the optical transmitter includes first and second optical transmitters 1 and 2, first and second alarm prohibition circuits 5,
6, first and second alarm memory circuits 7, 8, switching control circuit 4, setting circuit 9, timing circuit 10, power supply circuit 11
And an optical multiplexer 3.

The first and second optical transmission boards 1 and 2 supply a power supply voltage and a current necessary for the operation of the two optical transmission boards 1 and 2 from the power supply circuit 11. The optical transmission boards 1 and 2 adopt a cold standby system, and one of the optical transmission boards 1 (or 2)
Is turned on, the optical output is output to the optical multiplexer 3. The redundant switching between the optical transmission boards 1 and 2 is performed using the optical output disconnection alarm output from each of the optical transmission boards 1 and 2.
The alarm prohibition circuits 5 and 6 are generated in the optical transmission boards 1 and 2 by a switching procedure signal (switching code) sent from the setting circuit 9 that receives the forced switching signal and a timing signal input from the timing circuit 10. Receive the optical output disconnection alarm,
The fetch operation (prohibition release) and the prohibition operation are performed. The alarm memory circuits 7 and 8 receive an alarm signal from the alarm prohibition circuits 5 and 6 based on a switching procedure signal (switching code) sent from the setting circuit 9 and a timing signal input from the timing circuit 10 and store, Retain, delete, and reset.

Next, the switching control circuit 4 receives the optical output interruption alarm via the alarm prohibition circuit 5 or 6 and the alarm memory circuit 7 or 8 by the setting circuit 9, and is sent out from the setting circuit 9. Switching procedure signal (switching code) and timing circuit 1
0 from the power supply circuit 1
1 and a switching signal to the optical transmitters 1 and 2. The setting circuit 9 sends a switching procedure signal (switching code) to the switching control circuit 4, the alarm inhibition circuits 5, 6 and the alarm memory circuits 7, 8,
It is transmitted by a timing signal input from the timing circuit 10 and controls the setting of the operation release related to switching. The setting circuit 9 also controls the switching control circuit 4 according to the received signal.
Encoding (encoding) for generating signals for causing the alarm prohibition circuits 5 and 6 and the alarm memory circuits 7 and 8 to take in (prohibition cancellation), prohibit, store, hold, erase, and reset operations. Has functions. The timing circuit 10 supplies a timing signal to the alarm inhibition circuits 5 and 6, the alarm memory circuits 7 and 8, the switching control circuit 4, and the setting circuit 9. The reference of the timing of a switching procedure signal (switching code) for taking in (prohibiting release), prohibiting, storing, holding, deleting and resetting the optical output disconnection alarm output from the optical transmitters 1 and 2 is generated.

On the other hand, the power supply circuit 11 supplies a power supply voltage and a current to the optical transmitters 1 and 2 according to the switching signal received from the switching control circuit 4. The optical multiplexer 3 inputs or outputs optical output signals of the optical transmitters 1 and 2. The switching control circuit 4, the alarm prohibiting circuits 5 and 6, and the alarm memory circuits 7 and 8 receive the switching procedure signal (switching code) sent from the setting circuit 9 and the timing signal input from the timing circuit 10. And a decoding (decoding) function for converting into a signal for performing each operation of fetching (removal of prohibition), prohibition, storage, holding, erasing, and resetting.

Next, the operation of the preferred embodiment of the redundant switching system of the optical transmitter according to the present invention shown in FIG. 1 will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 2 is a processing system diagram of a switching procedure signal (switching code) of the redundant switching method of the optical transmitter illustrated in FIG. FIGS. 3 to 10 are state transition flowcharts for explaining various operations of the redundant switching system of the optical transmission apparatus shown in FIG. As shown in FIG. 2, the optical transmitters 1 and 2 include alarm units 1a and 2a, setting / cancelling units 1b and 2
b, status notification units 1c and 2c. Switching control circuit 4
Has a decoding unit 4a and a setting / cancellation unit 4b. The alarm prohibition circuits 5 and 6 include the decoding units 5a and 6a and the setting /
It has release parts 5b and 6b. The alarm memory circuits 7 and 8
It has decoding units 7a and 8a and setting / cancelling units 7b and 8b. The setting circuit 9 has a receiving unit 9a, a setting / cancelling unit 9b, and an encoding unit 9c. The power supply circuit 11 has a setting / cancellation unit 11b and an output unit 11a.

Each output of the optical transmission boards 1 and 2 is supplied to an optical multiplexer 3, and the optical multiplexer 3 outputs if an optical signal of any one of the optical transmission boards 1 and 2 is input. . The optical transmission boards 1 and 2 employ a cold standby system that does not operate unless power is supplied from the power supply circuit 11. The setting circuit 9 and the switching control circuit 4 prevent the optical transmission boards 1 and 2 from operating simultaneously. Controlled. The switching of the optical transmitters 1 and 2 is performed by receiving the optical output disconnection alarm output from the optical transmitters 1 and 2 by the setting circuit 9 via the alarm prohibition circuits 5 and 6 and the alarm memory circuits 7 and 8. . Then, a switching procedure signal (switching code) is transmitted to the switching control circuit 4 to perform switching. The optical output interruption alarm is output when the optical output is stopped, and is always output from the optical transmitter 2 (or 1) in the cold standby state due to its nature. The optical transmission boards 1 and 2 are in cold standby with each other, and the switching control circuit 4 receives a switching procedure signal (switching code) for performing a predetermined operation from the setting circuit 9, and receives one of the lights. The transmission board 1 (or 2) is selected, and power is further received from the power supply circuit 11 to be turned on. Then, the optical output is transmitted, and the optical output interruption alarm is released. as a result,
The optical output is input or output to the optical multiplexer 3.

Next, the relationship between a specific procedure and a switching procedure signal (switching code) will be described. FIG. 11 shows the setting circuit 9
Switching code, setting state of optical transmitter 1 and optical transmitter 2
Indicates the setting state of. The switching code is “00”, “0”
1 "," 02 "," 03 "," 04 "," 05 "," 0 "
6 "and" 07 ". Each of these switching codes “0
The setting states of the optical transmission boards 1 and 2 at "0" to "07" are as shown in FIG. First, the operation when the switching code is "00" will be described with reference to the flowchart shown in FIG. The setting circuit 9 sends a switching procedure signal (switching code) “00” to the switching control circuit 4, the alarm prohibition circuit 5, the alarm memory circuit 7, the alarm prohibition circuit 6, and the alarm memory circuit 8. Therefore, the alarm prohibition circuit 5 receives this switching procedure signal (switching code), decodes (decodes) it in the decoding unit 5a, and releases (clears) the alarm prohibition operation (step A1). The alarm memory circuit 7 sets (sets) an alarm signal in the setting / cancellation section 7b so as to be writable (storable) (step A2). Alarm prohibition circuit 6
Sets the alarm prohibition operation in the setting / cancellation unit 6b (set)
(Step A3). Also, the alarm memory circuit 8 sets / prohibits the write prohibition (storage prohibition) of the alarm signal.
(Inhibit is set) (step A
4).

The switching control circuit 4 receives the switching procedure signal (switching code) “00”, decodes it by the decoding unit 4 a, and supplies a signal for supplying power to the optical transmission board 1. (Enable) is sent to the power supply circuit 11 (step A5). The power supply circuit 11 supplies the required power supply voltage and current to the optical transmission board 1, thereby
Releases the optical output interruption alarm, sends out the optical output, and selects the optical transmitter 1 (step A6). Then, a status notification signal (status) for notifying this status is transmitted to the setting circuit 9 (step A8). On the other hand, the optical transmitter 2 is not selected in the cold standby state (step A).
7) Therefore, no status notification signal (status) is sent.
Then, the optical transmitter 2 is in the off state, the optical output is not transmitted,
An optical output interruption alarm is output, and this state is sent to the setting circuit 9 (step A9). With this series of settings, the optical transmission board 1 is set to the active system, and the optical transmission board 2 is set to the standby system, and the process is terminated (step A10).

Next, when an optical output interruption alarm is generated in the optical transmission board 1, the alarm inhibition circuit 5 takes in the optical output interruption alarm, and the alarm memory circuit 7 stores and stores the alarm. Is sent to the setting circuit 9. This operation will be described with reference to the flowchart shown in FIG. The setting circuit 9 that has received the optical output disconnection alarm generated by the optical transmitter 1 sends the switching procedure signal (switching code) “01” to the switching control circuit 4, the alarm inhibition circuit 5, the alarm memory circuit 7, and the alarm inhibition circuit 6. And to the alarm memory circuit 8. The alarm prohibition circuit 5 receives the switching procedure signal (switch code), decodes (decodes) it in the decoding unit 5a, and sets (sets) the alarm prohibition operation in the setting / cancellation unit 5b (step B1). The alarm memory circuit 7 sets (inhibit is set) write / inhibit (memory inhibition) of the alarm signal in the setting / cancellation unit 7b (step B2). The alarm prohibition circuit 6 releases (clears) the alarm prohibition operation to the setting / release unit 6b (step B3). Further, the alarm memory circuit 8 sets (sets) the setting / cancellation unit 8b as to whether the alarm signal can be written (storable) (step B4).

Next, the switching control circuit 4 receives the switching procedure signal (switching code), decodes (decodes) the signal by the decoding unit 4a, and supplies a signal for supplying power to the optical transmission board 2. (Enable) to the power supply circuit 11 and a signal (disenable) for shutting off the power to the optical transmitter 1. The power supply circuit 11 supplies a necessary power supply voltage and current to the optical transmission board 2 and cuts off the supply of power to the optical transmission board 1. As a result, the optical transmission board 2 is selected, the optical output interruption alarm is released, the optical output is transmitted, and a state notification signal (status) for notifying this state is transmitted to the setting circuit 9 (steps B5 to B).
7). The optical transmission board 2 is turned on, transmits the optical output to the optical combiner 3, and does not output the optical output disconnection alarm to the setting circuit 9 (step B9). On the other hand, the optical transmitter 1 is released from the supply of the required power supply voltage from the power supply circuit 11, waits for the restoration and restoration of the failure, and does not send out the state notification signal (status) (step B8). With this set of settings,
The optical transmission board 2 becomes the working system, and the process ends (step B10).

Next, when the optical output disconnection alarm of the optical transmission board 1 is restored (failure recovery), the optical transmission board 1 should be remounted in the apparatus and used, and the status of the optical transmission board 1 is notified. A signal (status) is sent to the setting circuit 9 to make it into a failure recovery state. Therefore, as shown in FIG. 5, the setting circuit 9 outputs a status notification signal (status) indicating the failure recovery state of the optical transmission board 1.
Is received, and when a failure occurs in the optical transmission board 2, in order to switch to the optical transmission board 1, a state notification signal (status) of the optical transmission board 1 is held and a switching control signal is sent to the switching control circuit 4. (Switch code) “02” is transmitted. However, since the optical transmission board 2 is in operation, the setting conditions of the setting circuit 9 for the optical transmission board 2, the alarm prohibition circuit 5, the alarm memory circuit 7, the alarm prohibition circuit 6 and the alarm memory circuit 8 are not changed. (Steps C1 to C1)
7). When the switching procedure signal (switching code) “02” is transmitted from the setting circuit 9, the optical transmission board 1 becomes an optical transmission board in a cold standby state, and is used for the standby system (steps C8 to C10).

Next, when an optical output interruption alarm is generated in the optical transmission board 2, the alarm inhibition circuit 6 takes in the optical output interruption alarm, and the alarm memory circuit 8 stores it. The stored alarm is sent to the setting circuit 9. As shown in the flowchart of FIG. 6, the setting circuit 9 that has received the optical output disconnection alarm generated in the optical transmitter 2 sends the switching procedure signal (switching code) “03” to the switching control circuit 4, the alarm prohibition circuit 5, and the alarm. The data is sent to the memory circuit 7, the alarm prohibition circuit 6, and the alarm memory circuit 8. The alarm prohibition circuit 5 receives the switching procedure signal (switching code) “03”, decodes (decodes) it, and releases (clears) the alarm prohibition operation (step D1).
The alarm memory circuit 7 sets (sets) the alarm signal to be writable (storable) (step D2). The alarm prohibition circuit 6 sets (sets) an alarm prohibition operation (step D3). Further, the alarm memory circuit 8 sets the write inhibition (storage inhibition) of the alarm signal (sets the inhibit).
(Step D4).

The switching control circuit 4 receives the switching procedure signal (switching code) “03”, decodes (decodes) it, and supplies a signal (enable) for supplying power to the optical transmitter 1. It is sent to the circuit 11 (step D5). Further, a signal (dis-enable) for cutting off the power is sent to the optical transmission board 2, and the power supply circuit 11 supplies the power supply voltage and current required for the optical transmission board 1 (step D).
6) The power supply to the optical transmitter 2 is cut off (step D7). As a result, the optical transmitter 1 cancels the optical output interruption alarm, sends out the optical output, and sends out a status notification signal (status) for notifying this status to the setting circuit 9 (step D8). On the other hand, the optical transmission board 2 includes a power supply circuit 11
From the required power supply voltage, and waits for fault repair and recovery. The status notification signal (status)
No transmission is made (step D9). With this set of settings,
The optical transmission board 1 becomes the working system (return), and switches back,
The process ends (Step D10).

Next, as shown in the flowchart of FIG.
When the optical output disconnection alarm of the optical transmitter 2 is restored (failure recovery)
For the reason described above, a status notification signal (status) is sent to the setting circuit 9 in the same manner as in the optical transmission board 1 for the above-mentioned reason, and a failure recovery state is set. The setting circuit 9 receives a status notification signal (status) indicating a failure recovery state of the optical transmission board 2, and switches to the optical transmission board 1 when a failure occurs in the optical transmission board 1. 2 while holding the state notification signal (status), and instructing the switching control circuit 4 to switch the switching procedure signal (switching code) "0"
4 ". However, since the optical transmission board 1 is in operation, the setting conditions of the setting circuit 9 for the optical transmission board 1, the alarm prohibition circuit 5, the alarm memory circuit 7, the alarm prohibition circuit 6 and the alarm memory circuit 8 are not changed. The switching procedure is held (steps E1 to E7). The optical transmission board 2 includes a setting circuit 9
When the switching procedure signal (switching code) "04" is transmitted from the optical transmission board, the optical transmission board is in the cold standby state and is used for the standby system (steps E8 to E10).

Next, as shown in the flowchart of FIG.
If an optical output disconnection alarm is generated in both systems of the optical transmission panel 1 and the optical transmission panel 2, the optical transmission panel 1 is supposed to generate an optical output disconnection alarm beforehand (switching procedure signal (switching signal from setting circuit 9)) After the transmission of the code "01"), the optical output disconnection alarm is generated in the optical transmission board 2 so that the optical output disconnection alarm of both systems is made. The alarm prohibition circuit 5 has already received the switching procedure signal (switching code) from the setting circuit 9 in response to the optical output cutoff alarm of the optical transmitter 1, and sets (sets) the alarm prohibition operation by decoding (decoding) ( Step F1). The alarm memory circuit 7 sets the alarm write inhibition (storage inhibition) (sets the inhibit) (step F2). Next, the setting circuit 9
Since the switching procedure signal (switching code) is already “01”, the switching procedure signal (switching code) is set to “05” due to the occurrence of the optical output cutoff alarm of the optical transmitter 2. The switching control circuit 4, the alarm prohibition circuits 5, 6 and the alarm memory circuit 7,
8

The alarm inhibiting circuit 6 receives the switching procedure signal (switching code) and sets (sets) an alarm inhibiting operation by decoding (decoding) (step F3). The alarm memory circuit 8 sets the alarm write inhibition (storage inhibition) (sets the inhibit) (step F4). The switching control circuit 4 receives the switching procedure signal (switching code), and sends a signal (disenable) for shutting off the power to the optical transmission board 2 to the power supply circuit 11 by decoding (decoding) ( Step F5). The power supply circuit 11 includes the optical transmission board 2
The supply of power to is stopped (step F7). As a result, the supply of the necessary power supply voltage from the power supply circuit 11 to the optical transmission board 2 is released. As a result, the power supply of both systems is released. When the optical transmission board 2 generates an optical output disconnection alarm in advance and the optical transmission panel 1 generates an optical output disconnection alarm later, the reverse procedure is performed. (Switch code) is “05”.

When an optical output interruption alarm is generated in both systems of the optical transmission board, each optical transmission board is in a standby state for restoration, restoration, and failure recovery. The setting circuit 9 sets the switching procedure signal (switching code) to "01" or "03" based on the state notification signal (status) generated by the optical transmission board when any of the optical transmission boards is restored, restored, and recovered from the failure. appear.
Each of the alarm prohibition circuits 5, 6 and the alarm memory circuits 7, 8
A switching procedure signal (switching code) is received and decoded (decoded). Then, by performing a predetermined switching operation, recovery and recovery are performed. Switching procedure signal (switching code)
Is "00", only the device is restarted (steps F8 to F10).

Next, as shown in the flowchart of FIG.
When the optical transmission board 1 is operated and the optical transmission board 1 is switched to the optical transmission board 2 by forcible switching from the outside while the optical output disconnection alarm is not issued to the optical transmission board 1, the setting circuit 9 outputs the switching procedure signal. (Switch code) “06” is sent to the switch control circuit 4, the alarm prohibition circuit 5, the alarm memory circuit 7, the alarm prohibition circuit 6 and the alarm memory circuit 8. The alarm control circuit 5 receives the switching procedure signal (switching code) and sets (sets) an alarm prohibition operation by decoding (decoding) (step G).
1). The alarm memory circuit 7 sets writing inhibition (storage inhibition) of the alarm signal (sets inhibit) (step G2). The alarm prohibition circuit 6 releases (clears) the alarm prohibition operation (step G3). Alarm memory circuit 8
Sets (sets) the alarm signal as writable (storable) (step G4).

The switching control circuit 4 receives the switching procedure signal (switching code) “06” and decodes (decodes) a signal (enable) for supplying power to the optical transmission board 2. (Step G)
5). Further, a signal (disenable) for cutting off the power is sent to the optical transmitter 1 (step G6). The power supply circuit 11 supplies the necessary power supply voltage and current to the optical transmission board 2 and cuts off the power supply to the optical transmission board 1 (step G7). As a result, the optical transmission board 2 releases the optical output interruption alarm and sends out the optical output, and sends out a state notification signal (status) for notifying this state to the setting circuit 9 (step G9). On the other hand, the optical transmission board 1 is released from the required power supply voltage from the power supply circuit 11 and enters a cold standby state due to the power supply cutoff by forcible switching, and is a normal optical transmission board. Is generated (step G8). Also, no status notification signal (status) is sent. With this series of settings, the optical transmission board 2 becomes the active system by forced switching, and the optical transmission board 1 becomes the standby system in the cold standby state. In each circuit operation by the forced switching, the setting circuit 9 receives the forced switching signal. Since the setting operation is controlled by the setting circuit 9, the circuit operation itself is the same as the switching procedure signal (switching code) “01” (step G10).

Next, as shown in the flowchart of FIG. 10, when the optical transmission board 2 is in operation, no optical output interruption alarm is generated in the optical transmission board 2 and the optical transmission board 1 is switched to the optical transmission board 1 by forced switching from outside the apparatus. When switching is performed, the setting circuit 9 sends a switching procedure signal (switching code) “07” to the switching control circuit 4, the alarm prohibition circuit 5, the alarm memory circuit 7, the alarm prohibition circuit 6, and the alarm memory circuit 8. . The alarm prohibition circuit 5 receives the switching procedure signal (switching code) “07”, decodes (decodes) it, and releases (clears) the alarm prohibition operation (step H1). The alarm memory circuit 7 sets (sets) the alarm signal as writable (storable) (step H).
2). The alarm prohibition circuit 6 sets (sets) an alarm prohibition operation (step H3). The alarm memory circuit 8 sets writing inhibition (storage inhibition) of the alarm signal (sets the inhibit) (step H4).

The switching control circuit 4 receives the switching procedure signal (switching code) “07”, decodes it (decodes), and
A signal (enable) for supplying power to the optical transmitter 1 is sent to the power supply circuit 11 (step H5). Further, a signal (disenable) for cutting off the power to the optical transmitter 2 is transmitted (step H7). Power supply circuit 1
1 supplies the necessary power supply voltage and current to the optical transmitter 1 (step H6), and cuts off the supply of power to the optical transmitter 2. As a result, the optical transmitter 1 cancels the optical output interruption alarm and sends out the optical output, and also sends out a state notification signal (status) for notifying this state to the setting circuit 9 (step H8). On the other hand, the optical transmission board 2 includes a power supply circuit 11
The required power supply from the power supply is released, the power supply is cut off by forced switching, and the system enters a cold standby state, and although the optical transmission board is normal, an optical output interruption alarm is generated. Further, the status notification signal (status) is not transmitted (step H9). With this series of settings, the optical transmitter 1
Becomes the active system by forced switching, and the optical transmission board 2 becomes the standby system in the cold standby state. In each circuit operation for the forced switching, the forced switching signal is received by the setting circuit 9 (step H10). The circuit operation itself is the same as the switching procedure (switching code) signal “03” because it is controlled by the setting circuit 9 according to a predetermined operation.

The configuration and operation of the preferred embodiment of the redundant switching system of the optical transmitter according to the present invention have been described above in detail. However, it should be noted that such exemplary embodiments are merely examples of the present invention and do not limit the present invention in any way.

[0035]

As can be understood from the above description, the redundant switching system of the optical transmitter according to the present invention has the following practically significant effects. First, switching conditions for failure, recovery, cold standby, and the like of an optical transmission board constituting a redundant system are set by a switching procedure signal (switch code) and supplied to each circuit to clarify the redundant operation.

Secondly, by providing a plurality of optical transmission boards and optical transmission sections and controlling them by using a switching procedure signal (switching code) in a switching system based on failure and recovery of the integrated optical transmission section, it is simple. And it can be reliably realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a preferred embodiment of a redundant switching system of an optical transmission device according to the present invention.

2 is a switching system signal (switching code) processing system diagram of a redundant switching system of the optical transmitter illustrated in FIG. 1;

FIG. 3 is a state transition flowchart showing an operation when a switching code of a setting circuit is “00” in the embodiment of the present invention.

FIG. 4 is a state transition flowchart showing an operation when a switching code of a setting circuit is “01” in the embodiment of the present invention.

FIG. 5 is a state transition flowchart showing an operation when a switching code of a setting circuit is “02” in the embodiment of the present invention.

FIG. 6 is a state transition flowchart showing an operation when a switching code of a setting circuit is “03” in the embodiment of the present invention.

FIG. 7 is a state transition flowchart showing an operation when the switching code of the setting circuit is “04” in the embodiment of the present invention.

FIG. 8 is a state transition flowchart showing an operation when the switching code of the setting circuit is “05” in the embodiment of the present invention.

FIG. 9 is a state transition flowchart showing an operation when the switching circuit of the setting circuit is “06” in the embodiment of the present invention.

FIG. 10 is a state transition flowchart showing an operation when the switching code of the setting circuit is “07” in the embodiment of the present invention.

FIG. 11 is a table showing a relationship between a switching procedure signal (switching code) and an optical transmitter according to the present invention.

FIG. 12 is a block diagram of an optical transmission board using a conventional redundancy switching system (prior art 1).

FIG. 13 is a block diagram of an optical transmission board using a conventional redundancy switching system (prior art 2).

[Explanation of symbols]

 1, 2 optical transmitter 3 optical multiplexer 4 switching control circuit 5, 6 alarm prohibition circuit 7, 8 alarm memory circuit 9 setting circuit 10 timing circuit 11 power supply circuit 1a, 2a alarm section 4a-8a decoding section 1b-11b setting / Cancellation unit 9a Encoding unit (Reception unit)

Claims (5)

[Claims] A plurality of optical transmission boards; an optical multiplexer for receiving an optical output from the optical transmission boards; a switching control circuit for selectively operating the optical transmission boards as a working system or a standby system; In a redundant switching system for an optical transmission device including a control circuit and an alarm prohibition circuit and an alarm memory circuit connected between the optical transmission boards, a setting circuit for collecting and setting a state of the optical transmission board, and the setting circuit And a timing circuit that supplies a timing signal for operating the switching control circuit, the alarm prohibition circuit, and the alarm memory circuit based on the setting information given by (1). 2. The optical transmission apparatus according to claim 1, wherein said setting circuit encodes a predetermined switching procedure signal based on an optical output cutoff alarm sent from said optical transmission board. Redundant switching method. 3. The alarm prohibition circuit and the alarm memory circuit include a decoding unit for decoding a code sent from the setting circuit and a setting / cancellation unit for setting and canceling a state. Item 3. A redundancy switching method for an optical transmission device according to item 1 or 2. 4. The setting circuit according to claim 1, 2 or 3, wherein a forced switching signal for forcibly switching is input to the setting circuit regardless of the optical output interruption alarm output from the optical transmission board. Redundancy switching method for optical transmitters. 5. The power supply circuit according to claim 1, further comprising a power supply circuit controlled by a switching control signal from said switching control circuit to supply operating voltages to said plurality of optical transmission boards. Redundancy switching method for optical transmitters.