JP3824219B2 - Optical transmission apparatus, optical transmission fault management method and program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a technology related to optical transmission failure avoidance, and in particular, by coordinating failure avoidance information with a user side by notifying the transmission source device on the user side that makes an optical transmission request of the optical transmission failure avoidance information. The present invention relates to an optical transmission apparatus and an optical transmission fault management method.
[0002]
[Prior art]
Currently, in an optical fiber communication network based on SONET (Synchronous Optical Network) and SDH (Synchronous Digital Hierarchy), in order to cope with optical transmission failure occurring in each path of the optical transmission path and to avoid this, optical transmission is performed. Duplexing (Line Protection) for each link and complete duplexing (Path Protection) of paths between user side terminal devices are performed.
When an optical transmission failure is detected, the optical transmission link is switched to the other (standby) link in the duplex link optical transmission network. In an optical transmission network in which the path between user-side terminal devices is completely duplexed, the user-side terminal device is notified of an optical transmission failure using SONET OAM (Operation Administration and Maintenance) information. The path is switched on the user side device.
[0003]
Also, in an optical transmission network (transparent network) composed of nodes that transmit information as optical signals without performing optical / electrical conversion at each node, an optical transmission failure occurred at any point (or path). In this case, it is necessary to switch the optical path in the node device that performs optical / electrical conversion.
[0004]
Further, along with the intelligentization of optical transmission networks such as GMPLS (Generalized Multi-Protocol Label Switching), avoidance calculation of optical transmission faults is dynamically performed in a mesh topology. Using an LMP (Link Management Protocol) channel control function or link connectivity verification function for an optical transmission device that performs relaying in a transparent network, links can be generated and optical transmission faults can be identified and isolated. It can be done (IETF draft-ietf-ccamp-lmp).
[0005]
[Problems to be solved by the invention]
However, in these optical transmission networks, network services that provide an optical path from an optical transmission network to a user terminal device through a user-network interface (UNI) to avoid an optical transmission failure are communicated with the user side (optical transmission). There is a problem that it is impossible to cooperate with the optical transmission network side (including the apparatus) for avoiding optical transmission faults.
The conventional SONET OAM is premised on protection for securing resources in advance. In particular, the operation of recalculating and resetting the route in the optical transmission network (excluding the termination point of the path) is not considered. Not in. In the case of a transparent network, the optical transmission failure is detected by a LOL (Loss of Light) or the like in the user terminal device earlier than notified from the optical transmission network.
[0006]
At this time, the user side does not know whether or not recovery is possible in the optical transmission network, and whether the path in which the optical transmission failure has occurred should be considered as down, or should it be considered that recovery is already in progress I don't know.
[0007]
The present invention has been made in view of the above-described problems, and the object thereof is to notify the user side of the optical transmission failure avoidance information to the user side that makes the optical transmission request, so that the user side can avoid the failure. An object of the present invention is to provide an optical transmission apparatus and an optical transmission fault management method capable of cooperating.
[0008]
[Means for Solving the Problems]
(1) In order to achieve the above object, in the optical transmission device according to the present invention, the optical transmission device arranged in an optical transmission network and relaying the wavelength transmitted through the optical transmission network transmits the wavelength. Detection means for detecting an optical transmission fault in a path in the optical transmission network, extraction means for extracting a faulty wavelength suffering the optical transmission fault based on the detection, and a source of the extracted faulty wavelength A hold instructing unit for instructing a source apparatus to hold the avoidance of the optical transmission fault, a calculation unit for calculating a fault avoidance path that substitutes for a path transmitting the faulty wavelength, and a fault avoidance path based on the calculation And a notification means for notifying the transmission source device of avoidance information on whether or not an optical transmission failure has been detected.
[0009]
(2) Further, in the optical transmission device according to the present invention, in the optical transmission device according to (1), the calculation means is within a predetermined period preset by a user corresponding to the transmission source device or by default. In addition, the failure avoidance route is calculated a plurality of times.
[0010]
(3) Further, in the optical transmission device according to the present invention, in the optical transmission device according to (1) or (2), wavelength transmission by wavelength division multiplexing is performed in the optical transmission network, The detecting means detects an optical transmission failure in a route in the optical transmission network transmitting the wavelength.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
FIG. 1 is a block diagram for explaining a network configuration example in which an optical transmission apparatus according to the present invention is used. FIG. 2 is a block diagram for explaining the configuration of the optical transmission apparatus according to the present invention. FIG. 3 is a flowchart for explaining an optical transmission failure management operation executed by the optical transmission apparatus of FIG.
[0012]
First, a configuration example of a network in which the optical transmission apparatus according to the present invention is used will be described with reference to FIG.
[0013]
In this network 1, the optical transmission apparatuses 100-1 to 100-4 are connected by links 30 to 36 that are optical transmission paths to constitute an optical transmission network 10. User devices 40 and 42 of users who use the optical transmission network 10 are connected to the optical transmission network 10 via links 20 and 22 provided with UNIs for performing bandwidth efficiency processing and the like.
[0014]
Next, the configuration of the optical transmission apparatus according to the present invention will be described with reference to FIG. In FIG. 1, the optical transmission apparatuses according to the present invention are the optical transmission apparatuses 100-1 to 100-4 having the same function, but here, the optical transmission apparatus 100-1 is taken up and described. To do.
[0015]
The optical transmission device 100-1 is an optical cross-connect type relay device having an optical fiber amplification function, and includes a light receiving unit 102, an optical amplification unit 104, an optical output unit 106, and an optical transmission failure processing unit 110. Has been.
[0016]
The light receiving unit 102 receives an optical signal having a wavelength division multiplexed WDM (Wavelength Division Multiplexing) wavelength transmitted from a receiving link which is an optical transmission path.
The optical amplifying unit 104 directly amplifies the (attenuated) optical signal.
The optical output unit 106 transmits and outputs the amplified optical signal to the transmission link.
[0017]
The optical transmission failure processing unit 110 includes a failure detection unit 112, a wavelength extraction unit 114, a route calculation unit 116, a hold instruction unit 118, and a notification unit 120.
[0018]
The failure detection unit 112 detects an optical transmission failure in a connected link in the optical transmission network 10.
Based on the detection of the optical transmission fault by the fault detection unit 112, the wavelength extraction unit 114 extracts a faulty wavelength that suffers from the optical transmission fault.
The hold instruction unit 118 transmits a signal instructing to hold the avoidance of the optical transmission failure to the transmission source device that is the transmission source of the failed wavelength extracted by the wavelength extraction unit 114.
[0019]
The route calculation unit 116 calculates a failure avoidance route that substitutes for the route that has transmitted the failed wavelength at predetermined intervals within a predetermined period preset by a user corresponding to the transmission source device or by default.
The notification unit 120 notifies the transmission source device of the avoidance information of the optical transmission failure whether or not the failure avoidance route is detected by the calculation of the route calculation unit 116.
[0020]
Next, an optical transmission failure management operation executed by the optical transmission apparatuses 100-1 and 100-3 having the same function will be described using the flowchart of FIG.
[0021]
When the user device 40 (transmitting side) and the user device 42 (receiving side) are communicating via the optical transmission network 10, the optical transmission device 100-1 and the optical transmission device 100-4 in FIG. Assume that an optical transmission failure has occurred in the connected link 34.
For this reason, the light receiving unit 102 of the optical transmission device 100-1 cannot receive the confirmation signal from the user device 42 on the receiving side. The failure detection unit 112 thereby detects an optical transmission failure (step S301). The wavelength extraction unit 114 extracts a failed wavelength that is a target of the failure (step S302). The hold instructing unit 118 transmits a signal for instructing to hold an operation for avoiding an optical transmission failure to the user device 40 on the transmission side of the extracted failure wavelength (step S303).
[0022]
The path calculation unit 116 of the optical transmission device 100-3 sets the failed wavelength at predetermined intervals (for example, every second) within a predetermined predetermined period (for example, 10 seconds) corresponding to the user device 40. A failure avoidance route that substitutes for the transmitted route is calculated (step S304).
[0023]
The notification unit 120 of the optical transmission device 100-3 notifies the user device 40 of optical transmission failure avoidance information indicating whether or not a failure avoidance route has been detected by this calculation at predetermined intervals (step S305). . If it is notified by the notification of the avoidance information by the notification unit 120 that a new failure avoidance path has been detected, transmission of wavelengths from the user apparatus 40 is performed based on the calculated failure avoidance path thereafter. This is performed (step S307). On the other hand, when the failure avoidance route is not calculated within the predetermined period (step S306), the notification unit 120 notifies the avoidance information that it is detected that the path is down (step S308). On the device 40 side, failure avoidance work (path setting) by itself is required.
[0024]
By using such an optical transmission device of the present invention, it is possible to notify the optical transmission failure avoidance information to a user-side transmission source device that makes an optical transmission request, and to cooperate with the user side for failure avoidance. Can be taken.
[0025]
In the above-described embodiment, the description has been made assuming a transparent network. However, the present invention can also be applied to GMPLS that can handle channels such as λ and SONET as labels. In this case, with the detection of an optical transmission failure by SONET OAM, a hold instruction is issued to the source device based on the label path. By performing the same operations as in steps S305 to S308 described above during this suspension, it is possible to obtain the same effect as that achieved by the above-described embodiment.
[0026]
In addition, this invention is not limited to the example of above-mentioned embodiment demonstrated using FIGS. 1-3, A various change is possible in the range which does not deviate from the summary. For example, in the above-described example, the optical transmission apparatus having an optical fiber type amplification function for WDM wavelength division multiplexing has been described. However, in addition to the optical transmission apparatus as a semiconductor optical amplifier, the optical transmission fault processing unit 110 in FIG. May be provided, or may be applied to an optical transmission network such as time division multiplexing other than wavelength multiplexing.
[0027]
Further, in the above-described embodiment, a program having the functions in the above steps S301 to S308 and various modifications, which is the optical transmission failure management method executed by the optical transmission apparatus, is produced and installed in each optical transmission apparatus. It can also be used. Alternatively, this program can be stored as application software in a recording medium such as a hard disk, and the program can be installed by installing the recording medium in an arbitrary computer, or they can be downloaded from another computer via a network. May be installed and used. Further, by storing in the recording medium in this way, the program or the like can be stored in a portable recording medium such as a CD-ROM for sale or carrying.
[0028]
【The invention's effect】
By using the optical transmission device according to the present invention, the optical transmission failure avoidance information is notified to the user-side transmission source device that makes an optical transmission request, and the user can cooperate with the failure avoidance. become.
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining an example of a network configuration in which an optical transmission apparatus according to the present invention is used.
FIG. 2 is a block diagram for explaining a configuration of an optical transmission apparatus according to the present invention.
FIG. 3 is a flowchart for explaining an operation executed by the optical transmission apparatus in FIG. 2;
[Explanation of symbols]
1: Network 10: Optical transmission network 20, 22, 30, 32, 34, 36: Link 40, 42: User devices 100-1 to 100-4: Optical transmission device 102: Light receiving unit 104: Optical amplification unit 106: Light Output unit 110: optical transmission failure processing unit 112: failure detection unit 114: wavelength extraction unit 116: path calculation unit 118: hold instruction unit 120: notification unit

Claims (6)

In an optical transmission device arranged in an optical transmission network and relaying a wavelength transmitted through the optical transmission network,
Detecting means for detecting an optical transmission failure in a path in the optical transmission network for transmitting a wavelength;
An extraction means for extracting a faulty wavelength suffering the optical transmission fault based on the detection;
And hold instruction means to instruct the source to become the source device of the disorder wavelength the extracted, so as to hold the avoidance operation in the source device side with respect to the optical transmission fault,
A calculation means for calculating a failure avoidance route that substitutes for the route that was transmitting the failed wavelength;
If a failure avoidance route is not detected within a predetermined period set by the calculation, the source device is notified that a failure avoidance work on the source device side is necessary, and the calculation is performed. And a notification means for notifying the transmission source device of information for instructing transmission based on the calculated failure avoidance route if the failure avoidance route is detected within a predetermined period set in advance. An optical transmission device. The optical transmission device according to claim 1,
The optical transmission apparatus characterized in that the calculation means calculates a failure avoidance path a plurality of times within a predetermined period preset by a user corresponding to the transmission source apparatus or by default. The optical transmission device according to claim 1 or 2,
In the optical transmission network, wavelength transmission by wavelength division multiplexing is performed,
An optical transmission apparatus characterized in that the detection means detects an optical transmission failure in a path in the optical transmission network that transmits the wavelength. Detecting an optical transmission failure in a path in the optical transmission network transmitting a wavelength;
Based on the detected knowledge, extracting the disorder wavelengths suffer optical transmission fault,
A step of instructing the source to become the source device of the disorder wavelength the extracted, so as to hold the avoidance operation in the source device side with respect to the optical transmission fault,
Calculating a fault avoidance path that substitutes for the path that was transmitting the wavelength of the fault;
If a failure avoidance route is not detected within a predetermined period set by the calculation, the source device is notified that a failure avoidance work on the source device side is necessary, and the calculation is performed. And a step of notifying the transmission source device of information instructing transmission based on the calculated failure avoidance route if the failure avoidance route is detected within a predetermined period set in advance. Optical transmission fault management method. The optical transmission failure management method according to claim 4,
The step of calculating the failure avoidance path comprises calculating a failure avoidance path a plurality of times within a predetermined period preset by a user corresponding to the transmission source device or by default. .   A program for causing a computer to execute each step in the optical transmission fault management method according to claim 4 or 5.

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