JP3885931B2 - Fault resource estimation method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a failure resource estimation method, and in particular, a communication network that does not have an optical-electric conversion unit in the middle of a communication path and that can perform quality monitoring of the communication path only at a receiving end, unlike an all-optical communication network. The present invention also relates to a failure resource estimation method that can estimate a failure resource.
[0002]
[Prior art]
When a failure such as a deterioration in communication path quality occurs in a communication network, it is required to quickly identify the cause of the failure in order to quickly take countermeasures and ensure communication. Conventionally, quality monitoring of a communication path in an optical communication network is performed in the middle of a communication path, for example, by providing an optical-electric conversion unit at a relay node and monitoring its electrical output, and is provided at a certain relay node. If the communication path quality degradation is detected due to a decrease in the electrical output of the optical-electrical converter, the cause of the degradation is identified as the failure resource from the preceding relay node to the relay node. Has been.
[0003]
[Problems to be solved by the invention]
The conventional fault resource identification method as described above needs to provide an optical-electric conversion unit in the middle of the communication path, but there is a part in which the optical-electrical conversion unit is provided in the middle of the communication path as in the all-optical communication network. In non-communication networks, such a method cannot be adopted. It is conceivable to monitor the quality of the communication path at the receiving end, but in that case, which of the resources used by the communication path has become a failure, causing the quality of the communication path to deteriorate. In particular, when the communication path is a long distance, it is difficult to specify the fault resource because the communication path includes many resources.
[0004]
The present invention estimates a fault resource even in a communication network that does not have an optical-electric conversion unit in the middle of the communication path and can only monitor the quality of the communication path at the receiving end of the communication path, unlike the all-optical network. It is an object of the present invention to provide a fault resource estimation method that can be used.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention uses at least a path from which failure path information is obtained using failure path information obtained at a receiving end and information on a path accommodated by each resource in a communication network. For each resource that is included, the ratio of the number of accommodated fault paths to the total number of accommodated paths is calculated. When this ratio is equal to or greater than a preset first threshold, the first feature is that the resource is estimated as a fault resource. is there.
[0006]
Further, the present invention uses at least the failure path information obtained at the receiving end and the information on the path accommodated by each resource in the communication network, for each resource including at least the path from which the failure path information is obtained. A second feature is that the ratio of the number of faulty paths accommodated to the number of faulty paths is calculated, and when the ratio is equal to or greater than a preset second threshold, the resource is estimated as a faulty resource.
[0007]
Furthermore, the present invention uses at least the failure path information obtained at the receiving end and the information on the paths accommodated by each resource in the communication network for each resource including at least the path from which the failure path information is obtained. The ratio of the number of accommodated failed paths to the number of accommodated paths is calculated, a resource having this ratio equal to or greater than a preset first threshold is estimated as a failed resource, and the number of accommodated failed paths relative to the total number of failed paths for each resource is further calculated. A third feature is that a ratio is calculated, and a resource whose ratio is equal to or higher than a preset second threshold is estimated as a failure resource.
[0008]
According to the first feature, a fault resource is estimated even in a communication network in which there is no optical-electric conversion unit in the middle of the communication path and the quality monitoring of the communication path can be performed only at the receiving end, as in the all-optical communication network. In particular, since the quality degradation of the communication path is determined based on the ratio of the number of accommodated failure paths to the total number of accommodated paths, it is possible to estimate a resource having a large degree of failure as a failure resource.
[0009]
In addition, according to the second feature, since the quality degradation of the communication path is determined based on the ratio of the number of accommodated failed paths to the total number of failed paths, the failed paths are distributed over a plurality of resources. In such a case, it is possible to estimate a resource having a relatively large influence on communication as viewed from the entire network as a failure resource because a large number of failure paths are particularly concentrated.
[0010]
Further, according to the third feature, the quality degradation of the communication path is determined based on both the ratio of the accommodated faulty path number to the total accommodated path number and the ratio of the accommodated faulty path number to the total faulty path number. Therefore, a large number of failure paths are concentrated with resources having a large degree of failure, and both resources having a relatively large influence on communication as viewed from the entire network can be estimated as failure resources.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of an all-optical communication network to which the present invention is applied. The all-optical communication network includes resources 1-1 to 1-8 such as optical fibers for transmitting wavelength-multiplexed optical information and optical cross-connect devices (hereinafter referred to as connect devices) A to E, 2-1 to 2-4 transmit and receive optical information using this network. In addition, a resource / failure management apparatus 3 is provided to estimate a failure resource in this network.
[0012]
The transmission / reception terminals 2-1 to 2-4 are configured to include an optical-electrical converter, and are connected to, for example, a user terminal to convert an electrical signal from the user terminal into optical information to connect devices A to D. The optical information from the connection devices A to D is converted into an electrical signal and sent to the user terminal. The transmission / reception terminals 2-1 to 2-4 include quality monitoring devices 2-1 to 2-4-1, respectively. The connecting devices A to E selectively output the optical information input by switching to the resources 1-1 to 1-8, and set the communication path between the transmitting and receiving ends.
[0013]
The quality monitoring device is provided at an end portion having a reception function in particular, and in the above embodiment, it is assumed that all the transmission / reception end portions A to D have a reception function. Although the quality monitoring device is provided, when there is an end portion having only a transmission function, the quality monitoring device at the end portion is not necessary. Also, a management device for switching the connection devices A to E and setting a communication path is necessary, but this management device is not required to be provided in particular, and the resource / failure management device 3 is provided with the function. Can be.
[0014]
The quality monitoring devices 2-1-1 to 2-4-1 provided at the transmission / reception terminals 2-1 to 2-4 monitor the quality of the communication path using electrical signals received through the opto-electric converters. When the quality degradation is detected, it is notified to the resource / failure management apparatus 3 as failure path information.
[0015]
In FIG. 1, there are three communication paths, that is, transmission / reception end 2-1 to connection device A to resource 1-1 to connection device D to transmission / reception end 2-2, transmission / reception end 2-1 to connection device A to resource 1-4. -Connect device B -Resource 1-3 -Connect device C -Resource 1-2 -Connect device D -Transmission / reception end 2-2 and Transmission / reception end 2-4 -Connect device B -Resource 1-3 -Connect device C -Transmission / reception end Although 2-3 communication paths are indicated by solid lines, in reality, more resources are attached to each of the connection devices A to E, and more resources are connected to each resource between the connection devices A to E. The communication path is set. In this state, for example, as shown in the figure, when a failure occurs in the resource 1-3, the quality monitoring device 2-2-1 of the transmission / reception end 2-2 is connected to the transmission / reception end 2-1 to the connection device A to the resource 1- 4 ~ connect device B ~ resource 1-3 ~ connect device C ~ resource 1-2 ~ connect device D ~ quality degradation of the communication path of the transmitting / receiving end 2-2 is detected, and the quality monitoring device 2- of the transmitting / receiving end 2-3 3-1 detects the quality degradation of the communication paths from the transmission / reception end 2-4 to the connection device B to the resource 1-3 to the connection device C to the transmission / reception end 2-3. To notify.
[0016]
The resource / failure management apparatus 3 identifies the failed resource using the notified failure path information and the resource management information stored in the internal resource management database. Here, the resource management information includes information on communication paths accommodated by each resource, for example, a path identifier (path number and the like). This information is stored in the resource management database as the communication path is set by switching the connection devices A to E.
[0017]
FIG. 2 is a flowchart showing the first embodiment of the present invention, and shows the processing contents in the resource / failure management apparatus 3. When the failure path information is notified from at least one of the quality management apparatuses 2-1 to 2-4, the resource / failure management apparatus 3 uses the failure path information and the resource management information, For each resource 1-1 to 1-8, the ratio of the number of accommodated fault paths to the total number of accommodated paths is calculated (S-1). Note that this calculation need not be performed for all the resources, but at least for each resource including the path from which the fault path information is obtained, in the case of FIG. 1, for each of the resources 1-2, 1-3, and 1-4. Good. Next, the calculated ratio is compared with a first threshold value, a resource equal to or higher than the threshold value is estimated as a failure resource (S-2), and the process ends. Here, for example, a value of about 80 to 90% is used as the first threshold value.
[0018]
The processes of S-1 and S-2 are processes for detecting whether or not a failure in a certain ratio or more of the paths accommodated by each resource is a failure. All the accommodated paths often fail, but the path accommodated by the resource is here considering that there may be a path that does not fail for some reason or is not detected as a fault. Whether or not the resource is a failure resource is detected based on whether or not a certain ratio or more is a failure.
[0019]
In FIG. 1, for simplification, only one path is shown for the resources 1-2 and 1-4. However, as described above, the resources 1-2 and 1-4 are actually used. Therefore, there are many paths that do not pass through the resource 1-3. Therefore, when a failure occurs in the resource 1-3, the ratio of the accommodated failure path number to the total accommodated path number for the resource 1-3 is the resource 1- Usually, the value is larger than the ratio of the number of accommodation failure paths to the total number of accommodation paths for 2 and 1-4.
[0020]
The fault resource can also be estimated by using the total number of fault paths instead of the total number of paths accommodated in the process of S-1. FIG. 3 is a flowchart showing the second embodiment of the present invention as described above. The resource / management apparatus 3 uses the failure path information and the resource management information from the quality management apparatus for each resource. The ratio of the number of accommodated failed paths to the total number of failed paths is calculated (S'-1). Note that this calculation need not be performed for all resources, and may be performed for each resource including at least a path from which fault path information is obtained. Next, the calculated ratio is compared with a second threshold value, a resource equal to or greater than the threshold value is estimated as a failure resource (S′-2), and the process is terminated. Here, for example, a value of about 70 to 80% is used as the second threshold.
[0021]
In the processing of S′-1 and S′-2, for each resource, whether or not a certain ratio or more of all the fault paths notified to the resource / fault management apparatus is a fault path in the resource. According to this process, when failure paths are distributed across multiple resources, many failure paths occur in a concentrated manner, and communication is seen from the entire network. A resource having a relatively large impact on the resource can be estimated as a fault resource.
[0022]
Moreover, a failure resource can also be estimated by combining the processes of FIGS. FIG. 4 is a flowchart showing the third embodiment of the present invention as described above. The resource / management apparatus 3 is configured such that the ratio of the number of accommodated fault paths to the total number of accommodated paths for each resource is greater than or equal to the first threshold value. When the ratio of the number of accommodated failure paths to the total number of failure paths satisfies any one of the second threshold and higher, the resource is estimated as a failure resource.
[0023]
In the present invention, the quality degradation of the communication path in the communication network is constantly monitored by the quality monitoring devices 2-1-1 to 2-4-1 provided at the transmission / reception ends 2-1 to 2-4, thereby communicating. When the path quality degradation is detected, the resource / fault management device 3 is immediately notified to that effect, so that the fault of the resource that has caused the quality degradation can be quickly identified, and the fault can be quickly detected. Measures can be taken to ensure communication.
[0024]
【The invention's effect】
As is apparent from the above description, according to the invention of claim 1, there is no optical-electrical converter in the middle of the communication path as in the all-optical communication network, and the quality monitoring of the communication path can be performed only at the receiving end. It is possible to estimate a failure resource even in a communication network that does not exist, and it is possible to estimate a resource having a particularly high degree of failure as a failure resource. According to the second aspect of the present invention, when a failure path is generated by being distributed over a plurality of resources, a large number of failure paths are generated in a concentrated manner. A resource having a relatively large impact on the resource can be estimated as a fault resource. Furthermore, according to the invention of claim 3, a large number of failure paths are concentrated with resources having a large degree of failure, and both of the resources having a relatively large influence on communication as viewed from the whole network are failed. It can be estimated as a resource.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an example of the configuration of an all-optical communication network to which the present invention is applied.
FIG. 2 is a flowchart showing a first embodiment of the present invention.
FIG. 3 is a flowchart showing a second embodiment of the present invention.
FIG. 4 is a flowchart showing a third embodiment of the present invention.
[Explanation of symbols]
1-1 to 1-8... Resource, 2-1 to 2-4 ... transmission / reception end, 2-1-1 to 2-4-1. Management device

Claims (3)

A communication network including a resource for transmitting optical information and an optical cross-connect device, wherein optical information input by switching of the optical cross-connect device is selectively output to a resource, and a communication path between transmission and reception ends is set In the fault resource estimation method in
Using the failure path information obtained at the receiving end and the information of the paths accommodated by each resource in the communication network, at least each resource including the path from which the failure path information is obtained is accommodated for the total number of accommodation paths. A fault resource estimation method for calculating a ratio of the number of fault paths and estimating the resource as a fault resource when the ratio is equal to or greater than a preset first threshold. A communication network including a resource for transmitting optical information and an optical cross-connect device, wherein optical information input by switching of the optical cross-connect device is selectively output to a resource, and a communication path between transmission and reception ends is set In the fault resource estimation method in
Using the fault path information obtained at the receiving end and the path information accommodated by each resource in the communication network, at least the faults containing the fault path information for each resource including the path for which fault path information has been obtained A failure resource estimation method for calculating a ratio of the number of paths and estimating the resource as a failure resource when the ratio is equal to or greater than a preset second threshold value. A communication network including a resource for transmitting optical information and an optical cross-connect device, in which a communication path between transmission and reception ends in which optical information input by switching of the optical cross-connect device is selectively output to the resource is set In the fault resource estimation method in
Using the failure path information obtained at the receiving end and the information of the paths accommodated by each resource in the communication network, at least each resource including the path from which the failure path information was obtained contains accommodation failures for the total number of accommodation paths. A ratio of the number of paths is calculated, a resource having a ratio equal to or higher than a first threshold set in advance is estimated as a failure resource, and a ratio of the number of accommodated failure paths to the total number of failed paths is calculated for each resource. A failure resource estimation method for estimating a resource having a ratio equal to or higher than a preset second threshold value as a failure resource.

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