JP3956914B2 - Network switching method and network switching apparatus in wavelength division multiplexing communication network - Google Patents

Description

  The present invention relates to a network switching method and a network switching device in a wavelength division multiplexing communication network, and in particular, transmits an optical signal using a wavelength multiplexing technique, and switches a path for each wavelength at an intermediate node, and The wavelength is converted between nodes as necessary, and in the wavelength division multiplexing communication network to be transmitted, the path is replaced for each wavelength, the wavelength is converted between nodes as necessary, and the path and wavelength of the optical signal are switched. The present invention relates to a network switching method and a network switching device in a wavelength division multiplexing communication network having a network switching mechanism.

  FIG. 17 is a network diagram showing that in a conventional wavelength division multiplexing network, switching cannot be performed normally due to network switching of optical channels.

  As shown in the figure, two optical channels are set. The first optical channel (hereinafter referred to as the first optical channel) is set between the optical cross-connect device 1 and the optical cross-connect device 3 via the optical cross-connect device 2, and the second optical channel ( Hereinafter, the second optical channel) is set between the optical cross-connect device 4 and the optical cross-connect device 6 via the optical cross-connect device 5. In the figure, to simplify the explanation, only one-way connection of the same wavelength optical channel is shown between the optical channel termination points.

In order to perform switching for relieving user traffic between client devices against failure / degradation in a wavelength division multiplexing network, or switching based on a command from an operator, spare resources indicated by dotted lines in FIG. Reserved. Here, the reservation means that the setting of the optical switch is not actually set physically but only the setting is reserved. With this reservation, the wavelength between the optical cross-connect device 7 and the optical cross-connect device 8 in FIG. 17 can be shared by the spare for the first optical channel and the spare for the second optical channel. By appropriately assigning spare paths and wavelengths in this way, fewer spare resources (wavelengths) are required than optical channel switching (1 + 1 optical channel protection) that occupies a spare with a single optical channel, which is highly reliable and An economical wavelength division multiplexing network can be realized.

  As the switching, network switching is performed to change the optical switch setting of the switching destination and switch the optical channel (see, for example, Patent Document 1 and Non-Patent Document 1).

JP 2000-168877 A `` Demonstration of Fast Restoration for Distributed Control Plane on Photonic Network '', K. Shimono et al., 28th European conference on Optical Communication (ECOC), 7.4.2, Sep, 8-12, 2002

  When generating a normal optical channel, optical switches are set in order from the upstream, or optical switches are set in order from the downstream. Problems when this is adopted for switching in network switching of optical channels are shown below.

  A case where the optical channel is switched according to an instruction from the operator and the setting of the optical switch is changed from the downstream will be described with reference to FIG.

  The network switching management control unit 100 first changes the setting of the optical switch of the optical cross-connect device 3 and changes the setting of the optical switch of the optical cross-connect device 8. At this time, if the setting cannot be made due to the failure of the output port of the optical switch of the optical cross-connect device 8 or the failure of the switch setting control, the user traffic cannot be transferred even if it is switched to the switching destination. Even if the setting of the optical cross-connect device 3 is restored, the transfer of user traffic is stopped until the setting of the optical switch of the optical cross-connect device 3 is switched from the switching source to the original state. In addition, after the setting of the optical cross-connect device on the switching path is completed at the switching destination, an optical signal flows between the optical channel terminal portions at both ends. Therefore, if the switching setting is not completed, the user signal is defined by the optical channel by switching. I don't know if I can meet the quality

  In general, it is constantly monitored whether or not the optical channel satisfies the prescribed quality. Since the optical channel is in a disconnected state at the time of switching, an optical channel failure is detected at the optical channel termination unit and notified to the operation system.

  As described above, the conventional optical communication network has a problem that the normality of the switching destination cannot be confirmed when the optical channel network switching is provided.

  The present invention has been made in view of the above points, and confirms the normality of the switching destination. If the switching destination is abnormal, the optical node having the optical channel termination point is not switched, and the entire network is stable. It is an object of the present invention to provide a network switching method and a network switching device in a wavelength division multiplexing communication network having a switching mechanism.

  FIG. 1 is a diagram for explaining the principle of the present invention.

According to the present invention (claim 1) , an optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between the nodes, multiple optical channels are wavelength-multiplexed and transmitted to the transmission line using wavelength multiplexing technology,
In a node having an optical channel connection point, an optical channel is connected while switching paths for each wavelength,
At both ends of the optical channel, optical channels are connected with the same wavelength,
Wavelength multiplexing with a network switching mechanism that switches the optical channel to a different path by re-switching the path in units of optical channels, and switches the setting of the output wavelength as necessary at the optical channel termination points at both ends. In a network switching method in a communication network,
At the time of network switching,
Using one or more sets of switching destination confirmation optical channel termination circuits, perform node setting for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends.
Check if the quality specified in the optical channel is satisfied in the switching destination confirmation optical channel, and confirm that the quality is satisfied,
Perform path replacement setting in the node having the optical channel connection point of the optical channel switching destination (step 1),
After confirming that the path switching setting has been normally completed (step 2), the path switching in the node having the optical channel termination points at both ends is performed (step 3).

In the present invention (Claim 2) , when performing path replacement setting of a node having an optical channel termination point,
After stopping alarm detection or triggering alarm notification to the operation system, which is the trigger for network switching,
Set the path replacement in the node with the optical channel termination point,
Release the stop of alarm detection or alarm notification to the operation system.

In the present invention (Claim 3) , when performing path replacement setting of a node having an optical channel termination point,
After stopping the alarm detection of the alarm that is obvious that the alarm is detected and notified to the operation system by the route change setting or the alarm notification to the operation system is stopped,
Set the path replacement in the node with the optical channel termination point,
Releases the alarm detection set to stop or the alarm notification stop to the operation system.

According to the present invention (claim 4) , an optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between nodes, a plurality of optical channels are wavelength-multiplexed and transmitted to the transmission line by wavelength multiplexing technology,
In a node having an optical channel connection point, the optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary.
A network in a wavelength division multiplexing communication network having a network switching mechanism for switching the optical channel to a different path and, if necessary, a different wavelength by re-switching the path in units of optical channels and resetting the output wavelength as necessary. In the automatic switching method,
At the time of network switching,
Using one or more sets of switching destination confirmation optical channel termination circuits, perform node setting for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends.
Check if the quality specified in the optical channel is satisfied in the switching destination confirmation optical channel, and confirm that the quality is satisfied,
Change the path and set the output wavelength in the node that has the optical channel connection point of the optical channel switching destination,
After confirming that the path switching setting and the output wavelength setting have been normally completed in all the nodes having the optical channel connection point on the switching path, the path switching setting and the wavelength in the node having the optical channel termination points at both ends are confirmed. Set up.

In the present invention (Claim 5) , when performing the path switching of the node having the optical channel termination point and the output wavelength setting,
After stopping alarm detection or triggering alarm notification to the operation system, which is the trigger for network switching,
Change the path at the node with the optical channel termination point and set the output wavelength,
Stop the alarm detection at the end point of the optical channel that has been set to stop or stop the alarm notification to the operation system.

In the present invention (Claim 6) , when performing path switching and output wavelength setting of a node having an optical channel termination point,
Depending on the setting, an alarm is detected and the operation system is clearly notified. After stopping the alarm detection of the alarm or stopping the alarm notification to the operation system,
Change the path at the node with the optical channel termination point and set the output wavelength,
Stops detection of an alarm at an optical channel termination point that has been set to stop or stop alarm notification to the operation system.

  FIG. 2 is a principle configuration diagram of the present invention.

In the present invention (Claim 7) , an optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between the nodes, multiple optical channels are wavelength-multiplexed and transmitted to the transmission line using wavelength multiplexing technology,
In a node having an optical channel connection point, an optical channel is connected while switching paths for each wavelength,
At both ends of the optical channel, optical channels are connected with the same wavelength,
Wavelength multiplexing with network switching means for switching the optical channel to a different path by re-switching the path in units of optical channels, and switching the setting of the output wavelength as necessary at the optical channel termination points at both ends. A network switching device in a communication network,
At the time of network switching, use one or more sets of switching destination confirmation optical channel termination circuits to set the node for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends. Switching that confirms whether the quality is satisfied by the switching destination confirmation optical channel, confirms that the quality is satisfied, and performs path switching setting in the node having the optical channel connection point of the optical channel switching destination Setting means 110 ;
A setting confirmation means 120 for confirming that the route replacement setting has been normally completed;
The replacement setting means 110
After confirming that the operation was successful in setting confirmation means performs replacement of the path at a node having an optical channel termination point at both ends, a switching hands stage to perform network specific switch.

The present invention (Claim 8) is the replacement setting means,
When performing path switching settings for nodes with optical channel termination points,
After stopping alarm detection or triggering alarm notification to the operation system, which is the trigger for network switching,
Means for setting a path replacement in a node having an optical channel termination point and canceling the detection of a stopped alarm or the stop of alarm notification to the operation system.

Further, the present invention (claim 9) is the replacement setting means ,
When performing path switching settings for nodes with optical channel termination points,
By switching the path, the alarm is detected and an alarm is clearly notified to the operation system. After the alarm detection is stopped or the alarm notification to the operation system is stopped, the path is switched at the node having the optical channel termination point. Means for setting
It includes means for canceling the alarm detection set to stop or the alarm notification stop to the operation system.

In the present invention (claim 10 ), an optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between nodes, a plurality of optical channels are wavelength-multiplexed and transmitted to the transmission line by wavelength multiplexing technology,
In a node having an optical channel connection point, the optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary.
The network switching device includes network switching means for switching the optical channel to a different path and a different wavelength as necessary by re-switching the path in units of optical channels and resetting the output wavelength as necessary. And
During network switching, one or more sets of switching destination confirmation optical channel termination circuits are used to set the node for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends. Confirming that the quality is satisfied by the switching destination confirmation optical channel, confirming that the quality is satisfied , switching the path in the node having the optical channel connection point of the switching destination of the optical channel, and the output wavelength First setting means for setting;
Confirmation means for confirming that the path switching setting and the output wavelength setting are normally completed in all of the nodes having the optical channel connection point on the switching path;
A second setting means for performing path replacement setting and wavelength setting in nodes having optical channel termination points at both ends after the confirmation means confirming that the path replacement setting and output wavelength setting have been normally completed; Have

Further, the present invention (claim 11) is the second setting means ,
When changing the path of the node having the optical channel termination point and setting the output wavelength,
A means for switching the path in the node having the optical channel termination point and setting the output wavelength after performing alarm detection stop or alarm notification stop to the operation system, which is a trigger for network switching;
Means for canceling the alarm detection of the termination point of the optical channel set to stop or the stop of alarm notification to the operation system is included.

Further, the present invention (Claim 12), in the second setting means,
When performing path switching and output wavelength setting for nodes with optical channel termination points,
Depending on the setting, after stopping the alarm detection of the alarm that is obvious to be detected and notified to the operation system or stopping the alarm notification to the operation system, the path is switched and output at the node having the optical channel termination point. Means for setting the wavelength;
Means for canceling the alarm detection of the optical channel termination point set to stop or stopping the alarm notification to the operation system are included.

  According to the present invention, the optical cross-connect device having the optical channel connection point on the optical channel switching destination path is set in advance, and the optical channel between the nodes having the device setting and the optical channel termination point of the optical channel is set. Since the switching is performed only when the predetermined quality is satisfied, the quality of the optical channel when switching to the switching destination can be confirmed in advance. In other words, when the quality of the optical channel is not satisfied, switching as an optical channel can be prevented in advance, and a wavelength division multiplexing communication network having a stable network switching mechanism as a whole network can be provided.

  The present invention also provides the same effect when switching to a switching destination using a network switching mechanism according to an instruction from a network operator.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In the following first to third embodiments, an example is shown in which the optical channel is realized at the same frequency at the end and end (including cases where the end and end wavelengths are different between the switching source and the switching destination). In the sixth embodiment, an example in which the optical channel performs wavelength conversion as necessary for each node will be described.

[First Embodiment]
FIG. 3 shows a state before switching in the first embodiment of the present invention, FIG. 4 shows a state during switching confirmation, and FIG. 5 shows a state after completion of network switching.

Each of the optical cross-connect devices 1 to 8 is OR / OS (Optical Receiver / Optical Sender) for each optical signal between the duplexer and the optical switch and between the optical switch and the multiplexer. A regenerative relay unit consisting of For example, the optical cross connect apparatus 1 configuration, between the demultiplexer 11 ₁ and the optical switch 14, and between the optical switch 14 and the multiplexer 12 _1, regenerative relay unit 17 _1, regenerative relay unit 18 ₁ It has a regenerative repeater composed of Note that a regenerative repeater is connected to both ends of the optical switch of the optical cross-connect device, and the regenerative repeater is composed of, for example, an OR / OS.

  In addition, when there is an input signal to the OR, the regenerative repeater terminates or monitors a part of the optical channel monitoring byte defined in a part of the optical channel signal format as necessary, or both. Regenerate the signal and output it from the regenerative repeater.

  On the other hand, if there is no input signal to the OR, an optical channel quality monitoring byte defined in a part of the optical channel signal format is added as necessary and output as an output optical signal of the regenerative repeater.

  As shown in FIG. 3, two optical channels are set. The first optical channel (hereinafter referred to as the first optical channel) is set between the optical cross-connect device 1 and the optical cross-connect device 3 via the optical cross-connect device 2, and the second optical channel ( Hereinafter, the second optical channel) is set between the optical cross-connect device 4 and the optical cross-connect device 6 via the optical cross-connect device 5.

  In FIG. 3, in order to simplify the description, the optical channel is shown only in one direction of the same wavelength optical channel between the optical channel termination points.

  For the purpose of switching to relieve user traffic between client devices against failure / degradation in a wavelength division multiplexing network, or switching based on a command from an operator, spare resources indicated by dotted lines in FIG. Reserved. Here, the reservation means that the setting of the optical switch is not actually set physically but only the setting is reserved. Due to this reservation, the wavelength between the optical cross-connect device 7 and the optical cross-connect device 8 in FIG. 3 is shared by the spare for the first optical channel and the spare for the second optical channel.

  An example in which the network switching mechanism is performed on the first optical channel in response to a failure / degradation notification or an instruction from the operator will be described with reference to FIGS.

  The network switching management control unit 100-1 sends a route switching message 107-1 to the optical cross-connect device 7 so as to switch the route to the switching destination, and a route switching message so that the optical cross-connect device 8 switches the route to the switching destination. 108-1 is transmitted. The optical cross-connect device 7 and the optical cross-connect device 8 set the optical switch 74 and the optical switch 84, respectively, and perform desired path switching. If it is not possible, a response message of “impossible” is returned to the network switching management control unit 100-1.

  When the response message “impossible” is returned from at least one of the optical cross-connect device 7 and the optical cross-connect device 8, the network switching control unit 100-1 stops the network switching.

  When an “end” response message is returned from both the optical cross-connect device 7 and the optical cross-connect device 8, and at the regenerative repeater in the optical cross-connect device 3, the regenerative repeater in the optical cross-connect device 1 When the optical channel quality monitoring byte and other monitoring bytes are checked and the prescribed quality is satisfied, as shown in FIG. 5, the network switching management control unit 100 -1 transmits a path switching message 101-1 to the optical cross-connect apparatus 1 so as to switch the path to the switching destination, and transmits a path switching message 103-1 to the optical cross-connect apparatus 3 so as to switch the path to the switching destination. The optical cross-connect device 1 and the optical cross-connect device 3 set the optical switch 14 and the optical switch 34, respectively, and perform desired path switching, thereby completing the network switching for the first optical channel.

  The path switching messages 101-1 and 103-1 include wavelength switching information as necessary, and change the transmission wavelength at the optical channel termination unit of the optical cross-connect device 1 and the optical cross-connect device 3. The wavelength of the switching source optical channel and the wavelength of the switching destination optical channel may be different.

  In the present embodiment, the network switching management control unit 100-1 has been described as a single network. However, the network switching management control unit is distributed and deployed to each optical cross-connect device to perform path switching and the like. It is also possible to implement a message by exchanging and transferring messages between the network switching management control units.

[Second Embodiment]
FIG. 6 shows a state before switching in the second embodiment of the present invention, FIG. 7 shows a state during switching confirmation, and FIG. 8 shows a state after completion of network switching.

In this embodiment, the optical cross connect apparatus 1 and the optical cross-connect device 3, respectively, in terms of using the optical channel termination 13 _2, 33 ₂ for switching destination confirmation, different from the first embodiment.

  An example of an operation in which the network switching mechanism is performed on the first optical channel according to a failure / degradation notification or an instruction from the operator will be described with reference to FIGS.

  The network switching management control unit 100-2 sends a route switching message 107-2 to the optical cross-connect device 7 so as to switch the route to the switching destination, and a route switching message so that the optical cross-connect device 8 switches the route to the switching destination. 108-2 is transmitted. The optical cross-connect device 7 and the optical cross-connect device 8 set the optical switch 74 and the optical switch 84, respectively, and perform desired path switching. If the switching could not be performed, a response message of “impossible” is returned to the network switching management control unit 100-2.

  When the response message “impossible” is returned from at least one of the optical cross-connect device 7 and the optical cross-connect device 8, the network switching management control unit 100-2 stops the network switching. .

Also, network specific switching control unit 100-2, the optical cross-connect device path switch message 1 to switch the path to connect the optical channel terminating unit 13 ₁ for switching destination confirmation and regenerative relay unit 18 ₁ 111-2 Is transmitted to the optical cross-connect device 3 as a path switching message 113-2 for switching the path so as to connect the optical channel terminal for confirmation of the switching destination and the regenerative repeater.

  After this setting, the optical channel termination unit for confirming the switching destination of the optical cross-connect device 1 and the optical channel termination unit for confirming the switching destination of the optical cross-connect device 3 are logically connected. Check if the specified optical channel quality is met.

  As a result of the check, if the quality of the optical channel is not satisfied, the network switching is stopped.

  When the prescribed quality is satisfied, as shown in FIG. 8, a route switching message 101-2 is sent from the network switching management control unit 100-2 to the optical cross-connect device 1 so as to switch the route to the switching destination. Then, the path switching message 102-2 is transmitted to the optical cross-connect device 3 so as to switch the path to the switching destination. The optical cross-connect device 1 and the optical cross-connect device 3 set the optical switch 14 and the optical switch 34, respectively, and perform desired path switching, thereby completing the network switching for the first optical channel.

In this embodiment, the input unit and the switching destination in the optical cross connect apparatus 1 and the optical cross-connect device 3, the regenerative relay unit 18 ₂ of the optical switch output side of the switching destination playback relay unit having an optical channel termination point at both ends that it can output unit for confirming the operation of the regenerative repeater unit 37 ₂ of the optical switch input side of a regenerative relay unit of the Department is differs from the first embodiment.

  The optical cross-connect device used in the description of the present embodiment is similar to the first embodiment in that a regenerative repeater is provided between the duplexer and the optical switch, and the optical repeater is interposed between the optical switch and the multiplexer. Although the optical cross-connect device is provided with a regenerative repeater, the former or the latter regenerative repeater or both regenerative repeaters need not be provided.

  Note that the above-described path switching messages 101-2 and 104-2 include wavelength switching information as necessary, and change the transmission wavelengths at the optical channel termination units of the optical cross-connect device 1 and the optical cross-connect device 3. Also good.

  In the present embodiment, the network switching management control unit 100-2 has been described as a single unit in the network, but the network switching management control unit is distributed and deployed in each optical cross-connect device to perform path switching and the like. The message can also be realized by exchanging and transferring messages between the network switching management control units.

[Third Embodiment]
FIG. 9 is a diagram for explaining the operation in the third embodiment of the present invention.

  In the first embodiment and the second embodiment described above, the alarm detection stop of the optical channel termination points at both ends, which is the trigger for triggering the network switching of the first optical channel, or the alarm notification stop to the operation system, Alternatively, a node that has an optical channel termination point is configured to stop alarm detection of the optical channel connection point of the optical channel of the switching source that is assumed in advance by the switching or stop alarm notification to the operation system (step 101). (Step 102), the alarm detection stop cancellation of the optical channel termination points and the optical channel connection points at both ends of the stopped first optical channel or the alarm notification stop cancellation to the operation system is performed (step 102). Step 103).

  As a result, communication interruption between the optical channel termination points of the optical channel that occurs at the time of setting the switching of the path in the node having the optical channel termination point, particularly when performing network switching in response to a command from the network operator. Detection of unnecessary alarms associated with the system and unnecessary notifications to the operation system are suppressed.

  Note that the alarm detection stop or the alarm notification stop to the operation system in the flow indicates a relative procedure with the path replacement setting process in the node having the optical channel termination point. That is, for example, in the case of network switching based on a command from the network operator, the stop setting is from after the command from the network operator to the setting for switching the path of the optical switch in the node actually having the optical channel termination point. Any position may be used.

  Further, in the present embodiment, when the alarm at the optical channel end point triggers the network switching, the above-mentioned stop / stop cancellation is performed. Furthermore, although an alarm at an optical channel connection point is assumed as an alarm preliminarily assumed by the switching described above, other alarms may be included.

[Fourth Embodiment]
FIG. 10 shows a state before switching in the fourth embodiment of the present invention, FIG. 11 shows a state during switching confirmation, and FIG. 12 shows a state after completion of network switching. Each of the optical cross-connect devices 1 to 8 shown in the drawings has a wavelength conversion unit for each optical signal between the duplexer and the optical switch, and each optical signal between the optical switch and the multiplexer. On the other hand, it differs from the first embodiment described above in that a regeneration relay unit is provided.

Having for example, in the optical cross connect apparatus 1 of FIG. 10, the wavelength converter 15 ₁ between the demultiplexer 11 ₁ and the optical switch 14, a reproduction relay unit 16 ₁ between the optical switch 14 and the multiplexer 12 ₁ . Further, a wavelength converting unit 15 ₂ between the demultiplexer 11 ₂ and the optical switch 14, a reproduction relay unit 16 ₂ between the optical switch 14 demultiplexer 12 _2. The same applies to other optical cross-connect devices.

  In addition, when there is an input signal to the wavelength conversion unit, the wavelength conversion unit of each optical cross-connect device may include some optical channel monitoring bytes defined in a part of the optical channel signal format as necessary. Terminating or monitoring or both are performed, and output from the wavelength converter at a predetermined wavelength. On the other hand, when there is no input signal to the wavelength conversion unit, an optical channel quality management byte defined in a part of the optical channel signal format is added as necessary, and output as an output optical signal of the wavelength conversion unit. .

  As shown in FIG. 10, two optical channels are set. The first optical channel (hereinafter referred to as the first optical channel) is set between the optical cross-connect device 1 and the optical cross-connect device 3 via the optical cross-connect device 2, and the second optical cross-connect ( Hereinafter, the second optical channel) is set between the optical cross-connect device 4 and the optical cross-connect device 6 via the optical cross-connect device 5.

  Since the optical cross-connect device according to the present embodiment includes the above-described wavelength conversion unit, the optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary. In FIG. 10, only one-way connection of the same wavelength optical channel is shown between the optical channel termination points in order to simplify the description.

  A spare resource indicated by a dotted line in FIG. 10 in advance when generating an optical channel for switching to relieve user traffic between client devices against failure / degradation in a wavelength division multiplexing network or switching based on a command from an operator Is reserved. Here, the reservation means that the setting of the optical switch is not actually set physically but only the setting is reserved.

  Since the optical cross-connect device in the present embodiment includes the wavelength conversion unit described above, setting of a switching optical channel to which an optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary Is possible. By this reservation, the wavelength between the optical cross-connect device 7 and the optical cross-connect device 8 in FIG. 10 is shared by the spare for the first optical channel and the spare for the second optical channel.

  An example of an operation in which the network switching mechanism is performed on the first optical channel according to a failure / deterioration notification or an instruction from an operator will be described with reference to FIGS.

The network switching management control unit 100-3 outputs a path / wavelength switching message 107-3 to the optical cross-connect device 7 so as to switch the path and output wavelength to the switching destination, and outputs a path and output to the optical cross-connect device 8 as the switching destination. A route / wavelength switching message 108-3 is transmitted to switch the wavelength. Optical crossconnect unit 7 and the optical cross-connect device 8, respectively, the optical switch 74, the wavelength converting unit 75 ₁ and the optical switch 84, to set the wavelength converter 85 _2, when it can be switched each "end" Alternatively, when the switching cannot be performed, a response message having a content of “impossible” is returned to the network switching management control unit 100-3.

  The network switching management control unit 100-3 stops the network switching when a response message “impossible” is returned from at least one of the optical cross-connect device 7 and the optical cross-connect device 8. .

Of both the optical cross-connect device 7 and the optical cross-connect device 8, if the response message "End" is replied, and, in the wavelength conversion unit 35 ₂ in the optical cross-connect device 3, the reproduction of the optical cross connect apparatus 1 receives the optical signal from the relay unit 16 ₂ performs a check using the optical channel quality monitoring bytes and other monitoring bytes, if they meet a defined quality, network manner switched as shown in FIG. 12 From the management control unit 100-3, the path / wavelength switching message 101-3 is switched to the optical cross-connect device 1 so as to switch the path and wavelength to the switching destination, and the path / wavelength is switched to the optical cross-connect device 3 so that the path is switched to the switching destination. A switching message 103-3 is transmitted.

Each of the optical cross connect apparatus 1 and the optical cross-connect device 3, the optical switch 14, the wavelength converting unit 35 ₂ and the optical switch 34, by performing the switching of the wavelength conversion unit 35 _2, the network specifically switched for the first optical channel Complete. However, the optical channel terminating unit 13 _1, when the output wavelength is deployed a variable output, if necessary, shall change the output wavelength of the optical channel terminating unit 13 ₁ from switching source wavelength at this time.

  Note that the optical cross-connect device used in the description of the present embodiment is an optical cross-connect device having a wavelength converter between the duplexer and the optical switch. Instead, the optical cross-connect device and the optical switch are multiplexed. A wavelength conversion unit may be provided between the duplexer and the regenerative repeater between the duplexer and the optical switch. In this case, the function of the wavelength conversion unit converts an arbitrary input wavelength into a fixed output wavelength.

  In the present embodiment, the network switching management control unit 100-3 has been described as a single network, but the network switching management control unit is distributed and deployed in each optical cross-connect device to switch routes, etc. This message can also be realized by exchanging and transferring messages between the network switching management control units.

[Fifth Embodiment]
FIG. 13 shows a state before switching in the fifth embodiment of the present invention, FIG. 14 shows a state during switching confirmation, and FIG. 15 shows a state after completion of network switching.

  Further, the optical cross-connect device 1 and the optical cross-connect device 3 are different from the above-described fourth embodiment in that an optical channel terminal unit for switching destination confirmation is used.

  An operation example in which the network switching mechanism is performed on the first optical channel according to a failure / degradation notification or an instruction from the operator will be described with reference to FIGS.

The network switching management control unit 100-4 switches the path and wavelength to the optical cross-connect device 7 so as to switch the path and wavelength to the switching destination, and switches the path and wavelength to the optical cross-connect device 8 so as to switch to the switching destination. A route switching message 108-4 is transmitted. Each of the optical cross-connect device 7 and the optical cross-connect device 8 performs optical switch 74, the wavelength converting unit 85 _1, 85 ₂ and the optical switch 84, the setting of the wavelength conversion unit 85 ₁ performs switching of the desired path, wavelength In the case where the switching can be performed, a response message of “end” is returned to the network switching management control unit 100-4.

  When a response message “impossible” is returned from at least one of the optical cross-connect device 7 and the optical cross-connect device 8, the network switching management control unit 100-4 stops the network switching.

Also, network specific switching control unit 100-4, the route / wavelength switching for switching the path and wavelength so as to connect the optical cross connect apparatus 1 and the optical channel terminating unit 13 ₁ for switching destination confirmation and regenerative relay unit 16 ₁ the message 111-4, and sends the path / wavelength switching message 113-4 to switch the path and wavelength as the optical cross-connect device 3 and the optical channel end portion 33 ₁ for switching destination confirmation to connect the regenerative relay unit.

After this setting, the optical cross-connect device the optical channel terminating unit 13 ₁ of the switching destination confirmation of 1 and the optical channel end portion 33 ₁ of the switching destination confirmation of the optical cross-connect device 3 is logically connected, the two In step (1), it is checked whether or not the quality of the optical channel defined in advance is satisfied.

  As a result of the check, if the quality of the optical channel is not satisfied, the network switching is stopped.

  When the specified quality is satisfied, the path / wavelength switching is performed so that the path and wavelength are switched from the network switching management control unit 100-4 to the optical cross-connect device 1 as a switching destination as shown in FIG. The message 101-4 is transmitted to the optical cross-connect device 3 so as to switch the path and wavelength to the switching destination.

Optical cross connect apparatus 1 and the optical cross-connect device 3, respectively, the optical switch 14, optical switch 34, by performing the switching of the wavelength converter 33 _1, network specific switching to the first optical channel is completed. However, when the output wavelength of the optical channel termination unit 131 is variable, the output wavelength of the optical channel termination unit 131 is switched at this time and changed from the original wavelength as necessary.

In this embodiment, in the optical cross-connect device 1 and the optical cross-connect device 3 having the optical channel termination points 13 ₁ and 33 ₁ at both ends, the OR on the output side of the optical switch of the regenerative repeater at the switching destination, The point of being able to confirm the operation of the OS on the optical switch input side of the wavelength conversion unit is different from the fourth embodiment described above.

  The optical cross-connect device used in the description of the present embodiment is an optical cross-connect device in which a regenerative repeater is provided between the optical switch and the multiplexer, as in the fourth embodiment. A regenerative repeater may not be provided.

  The optical cross-connect device used in the description of the present embodiment is an optical cross-connect device including a wavelength converter between the duplexer and the optical switch. Instead, the optical switch and the multiplexer A wavelength conversion unit may be provided between the two. In this case, the function of the wavelength conversion unit converts an arbitrary input wavelength into a fixed output wavelength.

In the optical cross connect apparatus 1, and 3 with an optical channel termination point used in the description in the present embodiment, the optical channel end for switching destination confirmation of the own device from the wavelength converter 35 ₁ of the optical cross-connect device 3 When the optical switch sections 14 and 34 do not depend on the output wavelength depending on the input wavelength, the path / wavelength switching messages 111-4 and 113-4 do not include wavelength information or the path / wavelength switching. It is possible that the output wavelength of the wavelength converter is not physically converted by the messages 111-4 and 113-4.

  In the present embodiment, the network switching management control unit 100-4 has been described as a single unit in the network, but the network switching management control unit is distributed and deployed to each optical cross-connect device to perform path switching and the like. The message can also be realized by exchanging and transferring messages between the network switching management control units.

[Sixth Embodiment]
FIG. 16 is a diagram for explaining a sixth embodiment of the present invention.

  In the fourth embodiment and the fifth embodiment described above, the alarm detection stop of the optical channel termination points at both ends, which is the trigger for triggering the network switching of the first optical channel, or the alarm notification stop to the operation system, Alternatively, the alarm detection stop of the optical channel connection point of the optical channel of the switching source assumed in advance by the switching or the alarm notification stop to the operation system is performed (step 201), and the node having the optical channel termination point The path / wavelength switching is set (step 202), the optical channel termination points at both ends of the stopped first optical channel, the optical channel connection point alarm detection stop cancellation, or the alarm notification stop cancellation to the operation system, Perform (step 203).

  As a result, in particular, when performing network switching in response to a command from the network operator, it occurs between the optical channel termination points of the optical channel, which occurs when the path / wavelength switching setting is performed in the node having the optical channel termination point. Detection of unnecessary alarms due to communication disconnection and unnecessary notification to the operation system are suppressed.

  Stopping alarm detection at the optical channel termination points at both ends in this flow or stopping alarm notification to the operation system indicates a relative procedure with the path / wavelength switching setting processing at the node having the optical channel termination point. It is a thing. That is, for example, in the case of network switching based on a command from the network operator, the stop setting described above is performed after the network operator command, to switch the path / wavelength of the optical switch in the node that actually has the optical channel termination point. Any position up to the setting is acceptable.

  Further, in the present embodiment, an optical channel termination point alarm is an example of a network switching trigger, and an optical channel connection point alarm or the like is a network switching trigger. Target of stop / stop release. Furthermore, although an alarm at an optical channel connection point is assumed as an alarm preliminarily assumed by the switching, the other alarm may be included.

  The operation of the network switching management control unit 100 in each of the above embodiments is constructed as a program, installed in a computer used as the network switching management control unit, and executed by a control unit such as a CPU, or It is possible to distribute through a network.

  Further, the constructed program is stored in a hard disk device connected to a computer used as a network switching management control unit (device), a portable storage medium such as a flexible disk, a CD-ROM, etc. When implemented, it can also be installed and executed on the computer.

  The present invention is not limited to the above-described embodiment, and various modifications and applications can be made within the scope of the claims.

  The present invention relates to a wavelength division multiplexing communication network that performs transmission of an optical signal using wavelength multiplexing technology, converts a wavelength between nodes at an intermediate node, and converts the wavelength between nodes as necessary. Is available.

It is a figure for demonstrating the principle of this invention. It is a principle block diagram of this invention. It is a figure which shows the state before switching in the 1st Embodiment of this invention. It is a figure which shows the state in switching confirmation in the 1st Embodiment of this invention. It is a figure which shows the state after completion | finish of network switching in the 1st Embodiment of this invention. It is a figure which shows the state before the switch in the 2nd Embodiment of this invention. It is a figure which shows the state in switching confirmation in the 2nd Embodiment of this invention. It is a figure which shows the state after completion | finish of network switching in the 2nd Embodiment of this invention. It is a figure for demonstrating the operation | movement in the 3rd Embodiment of this invention. It is a figure which shows the state before the switch in the 4th Embodiment of this invention. It is a figure which shows the state in switching confirmation in the 4th Embodiment of this invention. It is a figure which shows the state after completion | finish of network switching in the 4th Embodiment of this invention. It is a figure which shows the state before the switch in the 5th Embodiment of this invention. It is a figure which shows the state in switching confirmation in the 5th Embodiment of this invention. It is a figure which shows the state after completion | finish of network switching in the 5th Embodiment of this invention. It is a figure for demonstrating the operation | movement in the 6th Embodiment of this invention. It is a figure which shows the conventional network.

Explanation of symbols

1-8 Optical cross-connect devices 10, 20, 30, 40, 50, 60 Client devices 11, 21, 31, 41, 51, 61, 71, 81 Demultiplexers 12, 22, 32, 42, 52, 62, 72, 82 multiplexers 13, 23, 33, 43, 53, 63 Optical channel terminators 14, 24, 34, 44, 54, 64, 74, 84 Optical switches 15, 25, 35, 45, 55, 65, 75, 85 Wavelength conversion unit 16, 26, 36, 46, 56, 66, 76, 86 Regenerative relay unit 100 Network switching management control unit 110 Replacement setting unit 120 Setting confirmation unit 130 Network switching unit 101, 102, 103, 104, 107, 108, 111, 113 Route switching message

Claims (12)

An optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between the nodes, multiple optical channels are wavelength-multiplexed and transmitted to the transmission line using wavelength multiplexing technology,
In a node having an optical channel connection point, an optical channel is connected while switching paths for each wavelength,
At both ends of the optical channel, optical channels are connected with the same wavelength,
Wavelength multiplexing with a network switching mechanism that switches the optical channel to a different path by re-switching the path in units of optical channels, and switches the setting of the output wavelength as necessary at the optical channel termination points at both ends. In a network switching method in a communication network,
At the time of network switching,
Using one or more sets of switching destination confirmation optical channel termination circuits, perform node setting for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends.
Check if the quality specified in the optical channel is satisfied in the switching destination confirmation optical channel, and confirm that the quality is satisfied,
Perform switching setting of the path in the node having the optical channel connection point of the optical channel switching destination,
A network switching method in a wavelength division multiplexing communication network, characterized in that, after confirming that the path switching setting has been normally completed, path switching is performed in nodes having optical channel termination points at both ends. When performing path replacement setting for a node having the optical channel termination point,
After performing the alarm detection stop or the alarm notification stop to the operation system that is the trigger for the network switching,
Set up the path replacement in the node having the optical channel termination point,
It stops the alarm detection or network specific switching method in a wavelength division multiplexing communication network of claim 1, wherein to release the alarm notification stop to the operation system. When performing path replacement setting for a node having the optical channel termination point,
After performing the alarm detection stop or alarm notification stop to the operation system, it is obvious that an alarm is detected and notified to the operation system by the route switching setting,
Set the path replacement in the node with the optical channel termination point,
The network switching method in the wavelength division multiplexing communication network according to claim 1 or 2 , wherein the alarm detection set to stop or the alarm notification stop to the operation system is canceled. An optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between nodes, a plurality of optical channels are wavelength-multiplexed and transmitted to the transmission line by wavelength multiplexing technology,
In a node having an optical channel connection point, the optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary.
A network in a wavelength division multiplexing communication network having a network switching mechanism for switching the optical channel to a different path and, if necessary, a different wavelength by re-switching the path in units of optical channels and resetting the output wavelength as necessary. In the automatic switching method,
At the time of network switching,
Using one or more sets of switching destination confirmation optical channel termination circuits, perform node setting for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends.
Check if the quality specified in the optical channel is satisfied in the switching destination confirmation optical channel, and confirm that the quality is satisfied,
Perform switching of the path and setting of the output wavelength in the node having the optical channel connection point of the optical channel switching destination,
After confirming that the path switching setting and the output wavelength setting have been normally completed in all the nodes having the optical channel connection point on the switching path, the path switching setting and the wavelength in the node having the optical channel termination points at both ends are confirmed. A network switching method in a wavelength division multiplexing communication network. When changing the path of the node having the optical channel termination point and setting the output wavelength,
After stopping alarm detection or triggering alarm notification to the operation system, which is the trigger for network switching,
Performs path switching and output wavelength setting in a node having the optical channel termination point,
5. The network switching method in a wavelength division multiplexing communication network according to claim 4, wherein the alarm detection at the termination point of the optical channel set to stop or the alarm notification stop to the operation system is canceled. When performing path switching and output wavelength setting of a node having the optical channel termination point,
According to the above settings, after performing an alarm detection stop of an alarm that is obvious that an alarm is detected and notified to the operation system or an alarm notification stop to the operation system is performed,
Performs path switching and output wavelength setting in a node having the optical channel termination point,
6. The network switching method in a wavelength division multiplexing communication network according to claim 4 or 5 , wherein the detection of the alarm at the stop point of the optical channel termination point or the stop of the alarm notification to the operation system is canceled. An optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between the nodes, multiple optical channels are wavelength-multiplexed and transmitted to the transmission line using wavelength multiplexing technology,
In a node having an optical channel connection point, an optical channel is connected while switching paths for each wavelength,
At both ends of the optical channel, optical channels are connected with the same wavelength,
Wavelength multiplexing with network switching means for switching the optical channel to a different path by re-switching the path in units of optical channels, and switching the setting of the output wavelength as necessary at both ends of the optical channel A network switching device in a communication network,
At the time of network switching, use one or more sets of switching destination confirmation optical channel termination circuits to set the node for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends. Confirming that the quality is satisfied by the switching destination confirmation optical channel, confirming that the quality is satisfied, and performing path switching setting in the node having the optical channel connection point of the switching destination of the optical channel Replacement setting means,
Setting confirmation means for confirming that the route replacement setting has been normally completed;
The replacement setting means includes:
A network switching device comprising: a means for switching a path in a node having optical channel termination points at both ends after the setting confirmation means confirms normal termination. The replacement setting means includes:
When performing path replacement setting for a node having the optical channel termination point,
After performing the alarm detection stop or the alarm notification stop to the operation system that is the trigger for the network switching,
The network switching device according to claim 7 , further comprising means for setting a path replacement in a node having the optical channel termination point and canceling a stop alarm detection or a stop of alarm notification to the operation system. The replacement setting means includes:
When performing path replacement setting for a node having the optical channel termination point,
After stopping the alarm detection of the alarm that is obvious that the alarm is detected and notified to the operation system by the path switching setting, or the alarm notification to the operation system is stopped, the path of the node having the optical channel termination point is stopped. Means for setting replacement,
9. The network switching device according to claim 7 , further comprising means for canceling the alarm detection set to stop or the alarm notification stop to the operation system. An optical channel is connected between optical channel termination points via a plurality of optical channel connection points,
Between nodes, a plurality of optical channels are wavelength-multiplexed and transmitted to the transmission line by wavelength multiplexing technology,
In a node having an optical channel connection point, the optical channel is connected while switching the path for each wavelength or changing the output wavelength as necessary.
The network switching device includes network switching means for switching the optical channel to a different path and a different wavelength as necessary by re-switching the path in units of optical channels and resetting the output wavelength as necessary. And
During network switching, one or more sets of switching destination confirmation optical channel termination circuits are used to set the node for conducting the switching confirmation optical channel between the switching destination confirmation optical channel termination circuits at both ends. The switching destination confirmation optical channel is satisfied, and if the quality is satisfied, the path switching and the output wavelength at the node having the optical channel connection point of the optical channel switching destination are confirmed. First setting means for setting
Confirmation means for confirming that the path switching setting and the output wavelength setting are normally completed in all of the nodes having the optical channel connection point on the switching path;
Second setting means for performing path replacement setting and wavelength setting in nodes having optical channel termination points at both ends after the confirmation means confirms that the path replacement setting and output wavelength setting have been normally completed. And a network switching device characterized by comprising: The second setting means includes
When changing the path of the node having the optical channel termination point and setting the output wavelength,
A means for switching the path in the node having the optical channel termination point and setting the output wavelength after performing alarm detection stop or alarm notification stop to the operation system, which is a trigger for network switching;
11. The network switching device according to claim 10 , further comprising means for canceling the alarm detection of the termination point of the optical channel set to stop or the stop of alarm notification to the operation system. The second setting means includes
When performing path switching and output wavelength setting of a node having the optical channel termination point,
With the above settings, after stopping the alarm detection of the alarm that is obvious that the alarm is detected and notified to the operation system or the alarm notification to the operation system is stopped, the path in the node having the optical channel termination point is switched. And means for setting the output wavelength;
12. The network switching device according to claim 10 , further comprising means for canceling the alarm detection of the optical channel termination point set to stop or the stop of alarm notification to the operation system.

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