JP2765496B2 - Path route switching method for SDH transmission network - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route switching method for a transmission network, and more particularly to a path switching method for an SDH (synchronous digital hierarchy) transmission network.

[0002]

2. Description of the Related Art Conventionally, this type of path route switching system is:
In the SDH transmission network, a spare route is prepared in advance in preparation for a failure of the working path, and when a failure occurs in the working route, when the route connected to the path is switched to the protection route by the cross-connect device. Used.

The switching at the time of occurrence of a failure involves recovering the failed path as soon as possible and switching a normal path (in a bidirectional path, a path in the opposite direction to the failed path). Requires that the instantaneous interruption be as short as possible, and that the route can be surely switched using a part of the signal in the path.

FIGS. 5 and 6 are diagrams showing a path configuration of a conventional SDH transmission network.

Referring to FIGS. 5 and 6, a network monitoring and control device 51 monitors and controls the path terminating devices 11 and 12 and the cross-connect devices 21 and 22 in the transmission network.

The bidirectional higher-order (AU3 or AU4) paths 1a and 1b are terminated in path terminators 11 and 12.

The cross-connect switches 33 of the cross-connect devices 21 and 22 are set such that the normal paths 1a and 1b pass through the working route 101.

[0008] A backup route 201 is prepared for the working route 101. The path formed in the backup route 201 is terminated by the cross-connect devices 21 and 22.

The path trace IDs (PID1a, PID1b) unique to the J1 byte in the path overhead of the paths 1a and 1b are stored in the network by the path terminating devices 11 and 12.
Is transferred.

Further, like the path formed in the backup route 201, the J1 byte of the path terminated by the cross-connect devices 21 and 22 is also stored in the cross-connect device 2.
The path trace ID (PID 201a, PID
ID 201b) is transferred.

The path trace ID is transferred by a multi-frame of J1 bytes.

FIG. 4 shows a conventional cross-connect device 21,2.
2 is a block diagram showing a configuration of FIG.

The section adaptation unit 37 multiplexes higher-order path frames into section frames and separates the section frames into higher-order path frames. Further, it detects a path failure (P-AIS) and notifies the path monitoring unit management unit 31.

The path monitor 36 is assigned a unique (unique) device path ID in the apparatus, and the path monitor manager 31 manages each path monitor 36. In FIGS. 5 and 6, the path monitoring units 36 of the cross-connect devices 21 and 22 are provided on the path terminating devices 11 and 22 and on the network side (transmission / reception side), respectively. Section 36 is depicted as one element.

The path monitoring unit 36 monitors the path trace ID of the higher-order path received from the section adaptation unit 37 and transfers it to the path monitoring unit management unit 31.

The path monitoring section management section 31 holds the received path trace ID. The reception path trace ID is used to prepare for the case where monitoring cannot be performed due to a path failure or the like.
It is assumed that D is held.

The path monitoring unit 36 inserts the transmission path trace ID set in the path monitoring unit management unit 31 only for paths not connected by the cross-connect switch 33, such as backup paths, and performs section adaptation. To the unit 37.

The network monitoring and control device 51 includes an agent 34
Path trace ID of the path monitoring unit management unit 31 via the
, And setting of the transmission path trace ID, and setting of the cross-connect switch 33 via the cross-connect control unit 32.

The path monitoring section management section 31 notifies the network monitoring control apparatus 51 of a path failure (P-AIS).

Next, the switching operation in the conventional example will be described with reference to FIGS.

In the conventional example, the network monitoring controller 51 controls the cross connect switch 33 and compares the path trace ID.

When a path failure occurs in the working route 101b (indicated by a cross in the figure), the section adaptation unit 37 of the cross-connect device 21 detects a path failure (P-AIS) and sends it to the network monitoring controller 51. Notice.

As shown in FIG. 5A, the network monitoring and control device 51 instructs the cross-connect devices 21 and 22 to branch to the protection route 201 on the transmission side (step 1).

Next, as shown in FIG. 5B, the network monitoring controller 51 obtains the reception path trace monitor (ID) of the working route 101 and the protection route 201 from the cross-connect devices 21 and 22 (see FIG. 5B). Step 2).

The network monitoring controller 51 compares the received path trace monitors of the working route and the protection route and confirms that they match (in this example, the PID 1b and the cross connection device in the cross connection device 21 for both the working and protection routes). 22 becomes the PIDI 1a), the cross-connect device 2
The switching control of the receiving side path is performed so that the receiving sides 1 and 22 are changed from the working route 101 to the backup route 201 (step 3, see FIG. 6C).

Further, the network monitoring and control device 51 releases the branch on the transmitting side to the working route 201 for the cross-connect devices 21 and 22 (step 4, see FIG. 6 (D)).

[0027]

As described above, in the conventional path route switching system, the network monitoring and control device receives the notification of the path failure (P-AIS) of the working route and, at the same time, receives the crossover at both ends to be switched. Connect switch control,
It is necessary to perform a series of switching processes such as confirmation using the reception path trace ID, and the load on the network monitoring and control device in route switching is large.

Accordingly, an object of the present invention is to solve the above-mentioned problem, and in switching from the working route to the protection route due to a path failure, the switching process is performed between the cross-connect devices regardless of the control of the network monitoring and control device. An object of the present invention is to provide a path route switching method for an SDH transmission network that is performed autonomously.

[0029]

In order to achieve the above object, the present invention provides a cross-adaptation unit including a section adaptation unit for detecting a path failure and a path monitoring unit for monitoring and inserting a path trace ID of a path. A connecting device;
A working route and a protection route set between two opposing cross-connect devices, a path terminating device for terminating a path, and a setting between the two path terminating devices so as to pass through the working route or the protection route. In the path route switching method of the SDH transmission network including the two-way path, the cross-connect device sends the switching target device internal path I to the path monitoring unit management unit that manages the path monitoring unit.
D, and means for holding a path trace ID to be switched. The backup path monitoring unit management unit for the backup route sets the received path trace ID of the working route to the path trace to be switched. ID, an internal path ID of a path monitoring unit through which a working route passes is set as the internal path ID of the switching target, and the cross-connect device further includes a path trace ID of the switching target and the path monitoring unit. Means for detecting a match between the received path trace IDs of the backup routes monitored by the above-mentioned section, and further, when a path failure is detected in the section adaptation section of one cross-connect device, the path of the cross-connect device is detected. The monitoring unit management unit searches for a route in which the path ID within the device to be switched indicates the route in which the failure is detected, determines a backup route, and determines the active route on the transmission side. Means for branching the backup path to the backup route, and means for detecting a match of the reception path trace ID of the backup route in another cross-connect device opposite to the one cross-connect device that performed the branch. When a match is detected with the path trace ID to be switched, the switching start of the route of the one cross-connect device is recognized, the receiving side of the working route is switched to the backup route, and the transmitting side is branched to the backup route. Means and a means for detecting a match between the reception path trace ID of the backup route and the matching path detection ID in the one cross-connect device. Means for switching to a backup route. A path route switching method for an SDH transmission network is provided.

[0030] In the present invention, preferably, the working Lou
At the point in time when the backup route and the backup route are provided, the network monitoring control device causes the backup route path monitoring unit to change the reception path trace ID of the working route to the path trace ID of the switching target.
In addition, the internal path ID of the path monitoring unit through which the working route passes is set as the internal path ID of the switching target.

[0031] In the present invention, preferably, the cross-connect device, and a local control unit in the cross-connect control unit comprises a remote control unit, and as a means for detecting the coincidence of the received path trace ID, the path The monitoring unit management unit includes a path trace ID comparison unit, and the local control unit of the one cross-connect device that has detected the path failure stores, in the path monitoring unit management unit, an internal path I to be switched.
D searches the route indicating the route in which the failure is detected, determines a backup route, branches the transmitting side of the working route to the backup route, and, in another opposing cross-connect device, a path trace ID comparison unit of the backup route. Is the receive path trace I
The remote control unit detects the match between D and the path trace ID to be switched, recognizes the start of switching the route of the one cross-connect device, switches the receiving side of the working route to the backup route , and switches the transmission side to the backup route. branched, further, the even one cross-connect device, path trace ID comparing unit of the spare route detects coincidence of the received path trace ID and switching target path trace ID, the local control unit, the working Le
It is characterized in that the switching of the packet to the backup route on the receiving side and the release of the branch on the transmitting side are performed.

[0032]

According to the present invention, the path monitoring unit management unit of the backup route in the cross-connect devices at both ends of the switching route includes:
The switching target path trace ID and the switching target device path ID are held, and when a path failure is detected, switching control is performed between the cross-connect devices based on the switching target path trace ID and the switching target device path ID. With this configuration, it is possible to autonomously switch the path from the working route to the protection route without requiring control of the network monitoring and control device.

[0033]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a cross-connect device according to one embodiment of the present invention. In FIG. 1, elements having the same functions as those in FIG. 4 are denoted by the same reference numerals. With reference to FIG. 1, differences between the present embodiment and the configuration of the conventional example will be described below.

In this embodiment, the path monitoring unit management unit 3
In the case where the path monitoring unit 36 has become the backup route, 1 holds the switching target path trace ID and the switching target device internal path ID.

When the working route and the backup route are provided, the network monitoring and control device 51 causes the protection route path monitoring unit management unit 31 to set the reception path trace ID of the working route.
Is set to the switching target path trace ID, and the in-device path ID of the path monitoring unit through which the current route passes is set to the switching target device path ID.

Path trace ID comparing section 41 for backup route
Compares the received path trace ID received by the path monitoring unit 36 with the switching target path trace ID, and notifies the cross-connect control unit 32 of the coincidence when the two match.

The branch setting of the cross-connect is used only when the path route is switched, and the ID coincidence detection on the receiving side is used for the switching control.

The local controller 42 in the cross-connect controller 32 is for the cross-connect devices 21 and 22 that have detected a path failure (P-AIS) to perform switching control. Path failure (P-AI
S) and I from the path trace ID comparison unit 41
The control of the cross connect switch 33 is performed according to the D match notification.

The remote control unit 43 is used by a cross-connect device opposite to the cross-connect device that has detected a path failure to perform switching control.
The cross-connect switch 33 is controlled in accordance with the ID match notification from the comparing unit 41.

Next, the switching operation of this embodiment will be described with reference to FIGS.

When a path failure occurs in the working route 101b (indicated by a mark x in the figure), the section adaptation unit 37 of the cross-connect device 21 detects a path failure (P-AIS) and the path monitoring unit of the working route. The management unit 31 informs the cross-connect control unit 32 of a path failure (P-A
IS) (step 1, see FIG. 2A).

The local control unit 42 of the cross-connect device 21 searches the path monitoring unit management unit 31 for one whose path ID in the switching target device indicates a route in which a failure has been detected. The route managed by the corresponding path monitoring unit management unit 31 is the backup route.

The working route 101a on the transmitting side is changed to the protection route 201a via the cross-connect switch 33.
(Step 2, see FIG. 2B).

In the cross-connect device 22, the path trace ID comparison unit 41 of the backup route receives the received path trace ID.
And the switching target path trace ID (PIDia), and notifies the cross-connect control unit 32 of it.

The remote control unit 43 of the cross-connect control unit 32 recognizes that a path failure has been detected by the opposing cross-connect device 21 and that the route switching has been started. The corresponding working route is specified by referring to the path ID in the target device, and the receiving side of the working route 101a is set to the protection route 201a.
And the transmitting side branches to the backup route 201b (step 3, see FIG. 2C).

In the cross-connect device 21 as well, the path trace ID comparison unit 41 of the backup route matches the received path trace ID with the switching target path trace ID (PIDI).
b) is detected and notified to the cross-connect control unit 32.
The local control unit 42 of the cross-connect control unit 32 switches the receiving side in the opposing cross-connect device 22,
Recognizing that the branch on the transmitting side has been completed, the receiving side is switched from the working route 101b to the backup route 201b, and the branching to the working route 101a on the transmitting side is released (step 4, see FIG. 3D). .

In the cross-connect device 22, the reception path trace ID of the working route 101a changes (PIDI).
01a) Therefore, the remote control unit 43 recognizes that the switching of the route has been completed in the opposing cross-connect device 21, and releases the branch to the working route 201b on the transmitting side (step 5, see FIG. 3E). ).

As described above, according to the present embodiment, the path monitor ID of the switching target and the path ID of the switching target apparatus are held in the path monitoring unit manager 31 of the cross-connect devices 21 and 22 at both ends of the switching route, and the path failure is detected. At the time of detection, the switching control is executed between the cross-connect devices 21 and 22 based on the switching target path trace ID and the switching target device path ID.
, The path is automatically switched from the working route to the protection route.

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment but includes various embodiments according to the principle of the present invention.

[0051]

As described above, in the path route switching method according to the present invention (claim 1), the cross-connect devices at both ends of the switching route hold the path ID to be switched and the path ID in the device to be switched. When a failure is detected, the switching target path trace ID and the switching target device path I
Since the switching control is performed between the cross-connect devices based on D, there is an effect that the path from the working route to the protection route can be autonomously switched without requiring the control of the network monitoring control device. .

Further, according to the present invention (claim 2), the path trace I to be switched is stored in the path monitor manager of the backup route.
D and the path ID within the device to be switched are held, and when a path failure is detected, the path can be switched autonomously from the working route to the backup route, so that the load on the network monitoring and control device is particularly reduced. Have.

Further, according to the preferred embodiment of the present invention (claim 3), the control system can autonomously switch from the working route to the backup route without requiring control of the network monitoring and control device while suppressing an increase in the scale of the control system. This has the effect that path switching can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a cross-connect device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a switching operation in an embodiment of the present invention.

FIG. 3 is a diagram illustrating a switching operation in the embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a cross-connect device in a conventional example.

FIG. 5 is a diagram illustrating a switching operation in a conventional example.

FIG. 6 is a diagram illustrating a switching operation in a conventional example.

[Explanation of symbols]

 1a, 1b path 101a, 101b working route 201a, 201b backup route 11, 12 path terminating device 21, 22 cross-connect device 31 path monitoring unit management unit 32 cross-connect control unit 33 cross-connect switch 34 agent 35 section termination unit 36 path monitoring Unit 37 section adaptation unit 41 path trace ID comparison unit 42 local control unit 43 remote control unit 51 network monitoring and control device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification symbol FI H04M 3/00 H04Q 11/04 M H04Q 11/04 (58) Fields investigated (Int.Cl. ⁶ , DB name) H04J 3 / 00-3/26 H04L 1/22 H04L 12/24 H04L 12/26 H04Q 11/04 H04M 3/00

Claims (3)

(57) [Claims] 1. A cross-connect device including a section adaptation unit that detects a path failure, a path monitoring unit that monitors and inserts a path trace ID of a path, and a cross-connect device set between two opposing cross-connect devices. SDH transmission comprising: a working route and a protection route; a path terminating device that terminates a path; and a bidirectional path set between the two path terminating devices so as to pass through the working route or the protection route. In the network path route switching method, the cross-connect device stores, in a path monitoring unit management unit that manages the path monitoring unit, a device ID of a device to be switched and a device that stores a path trace ID of a device to be switched. In the backup route management unit , the received path trace ID of the working route is set to the path to be switched. Race I
D, the internal path ID of the path monitoring unit through which the working route passes is set as the internal path ID of the switching target, and the cross-connect device further includes the path trace ID of the switching target and the path monitoring unit. Means for detecting a match of the received path trace ID of the backup route monitored by the above. Further, when a path failure is detected in the section adaptation unit of one cross-connect device, the path of the cross-connect device is detected. Means for determining a backup route by searching the monitoring unit management unit for a route in which the path ID in the device to be switched indicates the failure detected route, and branching the working route on the transmission side to the backup route; In another cross-connect device that is opposite to the one cross-connect device that has performed, by means for detecting a match of the reception path trace ID of the backup route When a match between the received path trace ID and the path trace ID to be switched is detected, the start of switching the route of the one cross-connect device is recognized, the receiving side of the working route is switched to the backup route, and the transmission side is protected. Means for branching to a route, and means for detecting a match of the reception path trace ID of the backup route in the one cross-connect device,
Means for switching the receiving side of the working route to the backup route when a match between the received path trace ID and the switching target path trace ID is detected, comprising: a path switching method for an SDH transmission network. 2. When a working route and a backup route are provided
In the path monitoring unit of the backup route , the network monitoring control unit sets the received path trace ID of the working route to the path trace ID of the switching target, and sets the in-device path ID of the path monitoring unit through which the working route passes to the switching target. 2. The path route switching method for an SDH transmission network according to claim 1, wherein the path is set as an internal path ID. 3. The cross-connect device, further comprising: a local control unit and a remote control unit in a cross-connect control unit , wherein the path monitoring unit management unit is configured to detect a match between the reception path trace IDs. The local control unit of the one cross-connect device that has a trace ID comparison unit and detects a path failure searches the path monitoring unit management unit for a device whose switching target device path ID indicates a route in which a failure is detected. To determine the backup route and branch the transmitting side of the working route to the backup route. In the other cross-connect device, the path trace ID comparison unit of the backup route compares the reception path trace ID with the path trace ID to be switched. detecting a match, the remote control unit recognizes the switching start of route of the one cross-connect device, spare the recipient of the working route Branched transmission side switch to over preparative to the spare route, further wherein even in one of the cross-connect device, the spare route path trace I
D comparing section detects a match of the received path trace ID and switching target path trace ID, the local control unit, the working route
2. The path route switching method for an SDH transmission network according to claim 1, wherein the switching to the backup route on the receiving side and the release of the branch on the transmitting side are performed.