Administrative server, PON system, and switching method

Abstract

To shorten a recovery time when a failure occurs in a PON system.SOLUTION: An administrative server includes: a storage part that stores setting information for generating a setting file of an ONU corresponding to a plurality of OLTs; an acquisition part that acquires abnormality information related to one of the OLTs; and a generation part that generates the setting file based on the setting information of another OLT so that switching from the OLT related to the abnormality information to the another OLT becomes possible.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a management server, a PON system, and a switching method.

Background Art

[0002] Conventionally, in services such as FTTH (Fiber to the Home), a PON (Passive Optical Network) system that branches an optical signal into a plurality and shares a single optical fiber among a plurality of users has been used (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, when a failure occurs in an OLT (Optical Line Terminal) included in a PON system, it is required to shorten the time until the failure is recovered.

[0005] An object of the present disclosure is to shorten the recovery time when a failure occurs in a PON system.

Means for Solving the Problems

[0006] A management server according to an embodiment includes a storage unit that stores setting information for generating setting files of ONUs corresponding to a plurality of OLTs, an acquisition unit that acquires abnormality information related to any one of the OLTs, and a generation unit that generates a setting file based on the setting information of another OLT so that switching from the OLT related to the abnormality information to the other OLT becomes possible.

Effects of the Invention

[0007] According to the present disclosure, the recovery time in the event of a failure in the PON system can be shortened.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] [Description of Embodiment of the Invention of the Present Application] First, the content of the embodiment of the present disclosure will be listed and described.

[0010] [1] The management server according to one embodiment includes a storage unit that stores setting information for generating setting files of ONUs corresponding to a plurality of OLTs, an acquisition unit that acquires abnormality information related to any one of the OLTs, and a generation unit that generates a setting file based on the setting information of another OLT so that switching from the OLT related to the abnormality information to another OLT becomes possible.

[0011] In the management server described in [1] above, setting information for generating ONU configuration files for each of a plurality of OLTs in advance is stored. For example, when abnormal information is acquired from an OLT during operation, a configuration file for switching to another (standby) OLT is generated based on the setting information of the other OLT. According to such a configuration, when a failure occurs in an OLT, a configuration file for automatically switching to another (standby) OLT can be generated using the abnormal information of the OLT as a trigger. Thereby, the recovery time at the time of a failure in the PON system can be shortened.

[0012] [2] In the management server described in [1] above, the setting information may be wiring information of an optical switch configured to be able to switch the output destination OLT by switching an output port provided between the ONU and the plurality of OLTs. In this way, by setting the wiring information (optical wiring information) of the optical switch configured to be able to switch the output destination OLT by switching the output port as the setting information, the configuration file of the OLT after switching can be generated easily and appropriately. Thereby, the recovery time at the time of a failure can be made shorter.

[0013] [3] In the management server described in [2] above, the acquisition unit may acquire, as abnormal information, a signal notifying an abnormal state from the OLT in which a failure has occurred, or a signal from an optical switch that has detected a decrease in the optical level of the OLT in which a failure has occurred. According to such a configuration, abnormal information from the OLT in which a failure has occurred can be acquired appropriately and easily.

[0014] [4] In the management server described in [1] or [2] above, the acquisition unit may periodically acquire information from each OLT, compare the acquired information with a predetermined determination condition list, identify the OLT in which a failure has occurred based on the comparison result, and acquire the information related to the identified OLT as abnormal information. According to such a configuration, abnormal information can be derived (acquired) appropriately and easily based on the predetermined determination condition list prepared in advance. Also, since the determination is made based on the determination condition list, a uniform determination can be made regardless of the skill of the operator.

[0015] [5] In the management server according to [4] above, the determination condition list may include various information in a plurality of failure scenarios. According to such a configuration, abnormal information can be appropriately and easily derived (acquired) by comparing with the conditions at the time of an actual failure occurrence.

[0016] [6] The management server according to any one of [1] to [5] above may further include a switching control unit that switches the output port so that the output destination of the optical switch becomes another OLT when a setting file of another OLT is generated by the generation unit. According to such a configuration, it is possible to automatically perform up to the switching of the output port of the optical switch, and the recovery time at the time of a failure occurrence can be made shorter.

[0017] [7] A PON system according to an embodiment is a PON system including a plurality of OLTs and a management server that manages the plurality of OLTs, and the management server includes a storage unit that stores setting information for generating setting files of corresponding ONUs for the plurality of OLTs, an acquisition unit that acquires abnormal information related to any one of the OLTs, and a generation unit that generates a setting file based on the setting information of another OLT so that switching from the OLT related to the abnormal information to another OLT becomes possible.

[0018] [8] In the PON system according to [7] above, the OLT related to the abnormal information and another OLT may be OLTs of different models from each other. Thus, when the models of the OLTs before and after switching are different from each other, a process of converting the setting file (a process of newly generating a setting file) is required, and conventionally, it has taken time for the switching. In this regard, in the PON system according to this embodiment, when abnormal information is acquired, the setting file after switching is automatically generated as described above, so that even when OLTs of different models from each other are used before and after switching, the switching can be performed quickly.

[0019] [9]The switching method according to an embodiment is a switching method executed by a management server that manages a plurality of OLTs, and includes obtaining abnormal information related to any one of the OLTs, and generating a setting file for the corresponding ONU for each OLT stored in advance so that switching from the OLT related to the abnormal information to another OLT becomes possible, based on the setting information of the other OLT among the setting information for generating the setting file.

[0020] [Details of Embodiments of the Present Disclosure] Specific examples of embodiments of the present disclosure will be described below with reference to the drawings. The present invention is not limited to these examples, and is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

[0021] FIG. 1 is a configuration diagram of a PON system 1 according to the present embodiment. The PON system 1 is a system operated by an operator such as a CATV (Community Antenna TeleVision) operator. The PON system 1 is a network system that branches an optical signal into a plurality of signals and shares a single optical fiber among a plurality of users in providing an FTTH (Fiber to the Home) service. As shown in FIG. 1, the PON system 1 includes a plurality of ONUs 20 which are home-side devices, an OLT 30 which is a station-side device, an optical switch 40, and a management server 50. In FIG. 1, as the OLT 30, an operating OLT 30A and a standby OLT 30B are exemplified. The operating OLT 30A and the standby OLT 30B may be different models from each other or the same model as each other. Hereinafter, it will be described on the assumption that the OLTs 30A and 30B are different models from each other. The plurality of ONUs 20 are normally connected to the OLT 30A via an FTTH network, and the connection destination is switched to the OLT 30B when a failure occurs (details will be described later).

[0022] OLT 30A, OLT 30B, optical switch 40, and management server 50 may be provided in centers with different locations from each other (for example, within a center of a CATV operator), or at least some of them may be provided in the same center. Also, a plurality of ONUs 20 are respectively provided, for example, in each subscriber's home. Terminals such as telephones and PCs can be connected under the ONU 20 via an HGW (Home Gateway).

[0023] The optical switch 40 is provided between a plurality of ONUs 20 and OLTs 30A and 30B, and is a redundant optical switch configured to be able to switch the output destination OLTs 30A and 30B by switching the output ports. FIG. 2 is a diagram showing an example of the optical wiring related to the optical switch 40. As shown in FIG. 2, in the optical switch 40, normally, for example, the first output port 41 and the second output port 42 are respectively connected to the operation OLT 30A via optical cables. Also, in the optical switch 40, for example, the standby output port 45 can be connected to the standby OLT 30B via an optical cable, and the standby output port 46 can be connected to the standby OLT 30C via an optical cable. Here, the standby OLTs 30B and 30C are small-scale OLTs in a different housing from the operation OLT 30A. Thus, the operation OLT and the standby OLT do not necessarily have a one-to-one correspondence, and two standby OLTs 30B and 30C may correspond to one operation OLT 30A. For example, when using a small-scale OLT that has been used in the past as a standby for a new large-scale OLT, a configuration such as providing a plurality of standby OLTs for one operation OLT as described above may be adopted. According to such a configuration, when a failure occurs in the operation OLT 30A, it can be quickly switched to the standby OLT 30B or the like. Note that the optical switch 40 may have a function of automatically switching the output port to the standby system when, for example, detecting a decrease in the optical level of the operation OLT 30A.

[0024] Returning to FIG. 1, the functions of the management server 50 will be described. The management server 50 includes a database 51 (storage unit), a main processing unit 52, a setting file generation unit 53 (generation unit), and a switching control unit 54. The management server 50 is a server that realizes switching between, for example, OLTs 30A and 30B to be managed, even if they are of different models (details will be described later).

[0025] The database 51 stores setting information for generating setting files (details will be described later) of the corresponding ONUs 20 for a plurality of OLTs 30 (for example, operation OLT 30A and standby OLT 30B). The setting information here may include, for example, the wiring information of the optical switch 40. The database 51 stores the setting information for generating the setting files of the ONUs 20 for each of the OLTs 30A and 30B.

[0026] The main processing unit 52 has a batch processing unit 52a (acquisition unit) and a WebGUI application group 52b. The batch processing unit 52a is a function for performing various batch processes. For example, it acquires the abnormal information related to any one of the OLTs 30 (here, the operation OLT 30A). The batch processing unit 52a attempts to acquire the abnormal information, for example, at a predetermined time interval. The batch processing unit 52a may acquire, as the abnormal information, a signal (abnormal Trap) notifying the abnormal state from the OLT 30A where a failure has occurred, or a signal from the optical switch 40 that has detected a decrease in the optical level of the OLT 30A where a failure has occurred. Note that the signal from the optical switch 40 may be a signal (switching Trap) notifying that the output port has been automatically switched to the standby system upon detecting a decrease in the optical level. Also, the batch processing unit 52a may acquire the abnormal information from components other than the OLT 30A and the optical switch 40, for example, from the ONU 20.

[0027] The configuration file generation unit 53 generates the ONU 20 configuration file 100 based on the configuration information of the other (backup) OLT 30B so that switching from the OLT 30A related to the abnormal information to the other OLT 30B becomes possible. When the batch processing unit 52a acquires the abnormal information of the OLT 30A, the configuration file generation unit 53 refers to the database 51, acquires the configuration information of the backup OLT 30B, and generates the ONU 20 configuration file 100 for the OLT 30B based on the configuration information.

[0028] FIG. 3 is a diagram for explaining the generation of the ONU 20 configuration file. Now, assume that the configuration file for the operating OLT 30A has been originally generated as shown in the left diagram of FIG. 3. In the said configuration file, the communication service method (L3 service), the VLAN ID used for communication (100), the ONU firmware version (Ver. 2.0), the communication speed (1 Gbps), the OLT information of the ONU connection destination (OLT-A), and the ONU connection destination port No (first port) are defined. Among these, for example, the OLT information of the ONU connection destination and the like are information that can be set from the wiring information of the optical switch 40 stored in the database 51. When newly generating the ONU 20 configuration file for the backup OLT 30B (right diagram of FIG. 3), conversion processing is performed on the content of the above-mentioned configuration file for the operating OLT 30A. Such conversion processing is necessary because the OLTs 30A and 30B are different models from each other. Specifically, based on the information in the database 51, the ONU 20 configuration file 100 for the OLT 30B is generated in which the communication service method (L2 service), the VLAN ID used for communication (200), the ONU firmware version (Ver. 1.0), the communication speed (100 Mbps), the OLT information of the ONU connection destination (OLT-B), and the ONU connection destination port No (second port) are defined. Note that the set content is only an example.

[0029] The configuration file 100 for the ONU 20 for the OLT 30B generated by the configuration file generation unit 53 is stored in the management server 50 (for example, the database 51). Then, after the switching process of the optical switch 40 described later, the ONU 20 obtains the configuration file 100 and operates based on the configuration file 100.

[0030] When a configuration file for the standby OLT 30B is generated by the configuration file generation unit 53, the switching control unit 54 switches the output port so that the output destination of the optical switch 40 becomes the standby OLT 30B. Specifically, when the configuration file generation unit 53 generates a configuration file for the OLT 30B, the switching control unit 54 may switch the output port to the output port 45 shown in FIG. 2 so that the output destination of the optical switch 40 becomes the OLT 30B. Note that the switching control unit 54 may perform output port switching control only when the output port is not automatically switched by the optical switch 40.

[0031] Next, with reference to FIG. 4, a switching method (switching process) executed by the management server 50 will be described. FIG. 4 is a flowchart showing the switching process in the PON system 1.

[0032] As shown in FIG. 4, in normal operation, each ONU 20 is initially activated with the operation system being the OLT 30A (step S1), and the ONU 20 obtains a configuration file for the ONU 20 for the OLT 30A prepared in advance (step S2). The ONU 20 operates based on the configuration file.

[0033] Subsequently, the batch processing unit 52a of the main processing unit 52 of the management server 50 attempts to acquire abnormality information at a predetermined time interval. Specifically, in the batch processing unit 52a, for example, acquisition of abnormality information transmitted from the ONU 20 (step S3), acquisition of abnormality information transmitted from the OLT 30A (step S4), or acquisition of abnormality information transmitted from the optical switch 40 (step S5) is attempted.

[0034] When abnormal information is acquired, the setting file generation unit 53 of the management server 50 refers to the database 51, and based on the setting information of the OLT 30B, a setting file 100 for the ONU 20 for the OLT 30B is generated (step S6).

[0035] Subsequently, the switching control unit 54 of the management server 50 performs a switching operation of the output port so that the output destination of the optical switch 40 becomes the standby OLT 30B (step S7).

[0036] In this state, when the ONU 20 is restarted (step S8), the ONU 20 acquires a new setting file after switching (the setting file 100 for the ONU 20 for the OLT 30B) (step S9), and starts operating based on the setting file 100.

[0037] Next, the operation and effect of the management server 50 according to the present embodiment will be described.

[0038] First, referring to FIG. 5, the problems of the PON system 501 according to the comparative example will be described. FIG. 5 is a diagram for explaining the PON system 501 according to the comparative example. The PON system 501 according to the comparative example is generally the same as the above PON system 1 except that a management server 550 that does not have the switching function of the OLT described above is used as the management server.

[0039] The operation OLT 30A and the standby OLT 30B are each configured to include a housing, a control card for controlling each card, and a line card having ports connected to the ONUs 20. The ONUs 20 are connected to the OLT 30A or OLT 30B via optical cables and operate according to the configuration files stored in the management server 550. The ONUs 20 are connected in a one-to-many manner to one port of the line card by branching the optical cables. For this reason, if a failure occurs in the line card on the OLT 30A side, it becomes impossible to provide communication services with a large number of ONUs 20. The OLT 30B is a redundant configuration provided to avoid such a situation, and is configured to shorten the time until recovery by immediately switching to the normal system when a failure occurs.

[0040] The optical switch 40 monitors, for example, the optical level from the OLT 30A at the input port of the operation system, and has a function of automatically switching to the standby system, for example, when the optical level drops, and a function of manually switching to the standby system by an operation from the management server 550. However, such switching is possible only within the same housing. As shown in FIG. 5, between the OLTs 30A and 30B in different housings, the ONUs 20 do not start only by changing the path, and it is necessary to change the operation settings (configuration files) stored in the management server 550. And, looking at the entire failure, since there are many cases where switching is required between OLTs in different housings, a conventional management server such as the management server 550 according to the comparative example has not been able to sufficiently shorten the recovery time at the time of a failure.

[0041] As shown in FIG. 1, the management server 50 according to the present embodiment, which is configured to solve such problems, includes a database 51 that stores setting information for generating configuration files of the corresponding ONUs 20 for a plurality of OLTs 30A and 30B, a batch processing unit 52a that acquires abnormality information related to the operation OLT 30A, and a configuration file generation unit 53 that generates a configuration file based on the setting information of the standby OLT 30B so that switching from the OLT 30A related to the abnormality information to the standby OLT 30B becomes possible.

[0042] In such a management server 50, setting information for generating ONU configuration files for each of a plurality of OLTs 30A and 30B in advance is stored. For example, when abnormal information is acquired from the OLT 30A during operation, a configuration file for switching to another (backup) OLT 30B is generated based on the setting information of the other OLT 30B. According to such a configuration, when a failure occurs in the OLT 30A, a configuration file for automatically switching to another (backup) OLT 30B can be generated using the abnormal information of the OLT 30A as a trigger. Thereby, the recovery time in the PON system 1 at the time of a failure can be shortened.

[0043] In the management server 50, the setting information may be wiring information of an optical switch 40 configured to be able to switch the output destination OLT by switching an output port provided between the ONU 20 and the plurality of OLTs 30A and 30B. In this way, by using the wiring information (optical wiring information) of the optical switch 40 configured to be able to switch the output destination OLT by switching the output port as the setting information, the configuration file of the OLT after switching can be generated easily and appropriately. Thereby, the recovery time at the time of a failure can be made shorter.

[0044] In the management server 50, the batch processing unit 52a may acquire, as abnormal information, a signal notifying an abnormal state from the OLT 30A in which a failure has occurred, or a signal from the optical switch 40 that has detected a decrease in the optical level of the OLT 30A in which a failure has occurred. According to such a configuration, the abnormal information from the OLT 30A in which a failure has occurred can be acquired appropriately and easily.

[0045] The management server 50 may further include a switching control unit 54 that switches the output port so that the output destination of the optical switch 40 becomes another OLT 30B when a configuration file of another OLT 30B is generated by the configuration file generation unit 53. According to such a configuration, it is possible to automatically perform up to the switching of the output port of the optical switch 40, and the recovery time at the time of a failure can be made shorter.

[0046] Also, in the above PON system 1, the OLT 30A related to the abnormal information and another OLT 30B may be OLTs of different models from each other. In this way, when the models of the OLTs before and after the switching are different from each other, a process of converting the setting file (a process of newly generating the setting file) is required, so conventionally, it has taken time for the switching. In this regard, in the PON system 1 according to the present embodiment, when the abnormal information is acquired, the setting file after the switching is automatically generated as described above, so even when OLTs of different models from each other before and after the switching are used, the switching can be performed quickly.

[0047] As described above, the PON system according to the present embodiment has been described. However, the present invention is not limited to these, and various modifications can be applied. Also, the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above meaning but by the scope of claims, and it is intended that all changes within the meaning and scope equivalent to the scope of claims are included.

[0048] Hereinafter, the PON system and the management server according to the modification example will be described with reference to FIGS. 6 to 8. FIG. 6 is a configuration diagram of a PON system 1A according to the modification example. Note that for the PON system 1A according to the modification example, mainly the differences from the above-described PON system 1 will be described, and duplicate descriptions may be omitted.

[0049] As shown in FIG. 6, the management server 50A included in the PON system 1A further includes a failure determination unit 55 in addition to each function of the above-described management server 50. In the management server 50A, the batch processing unit 52a and the failure determination unit 55 function as an "acquisition unit".

[0050] The batch processing unit 52a periodically acquires information from each OLT (at least the operation-based OLT 30A). The information acquired here is not the above-mentioned abnormal information but information that can always be acquired. Specifically, it may be information indicating the operating state of the ONU 20, information indicating the upstream and downstream optical powers, a communication packet counter, etc. The batch processing unit 52a stores the acquired information in the database 51.

[0051] The failure determination unit 55 periodically compares the acquired information with a predetermined determination condition list, identifies the OLT 30A in which a failure has occurred based on the comparison result, and acquires the information related to the identified OLT 30A as abnormal information. The determination condition list may be various information in a plurality of failure scenarios.

[0052] FIG. 7 is a diagram for explaining the determination condition list. Note that the determination condition list shown in FIG. 7 is merely an example. In the example shown in FIG. 7, the determination condition list defines various conditions when a plurality of failure scenarios (failure scenario example 1, failure scenario example 2,...) are satisfied. For example, failure scenario example 1 assumes a failure in which the line card freezes. As conditions that are considered to be satisfied in that case, condition 1: the operating state of the ONU is normal, condition 2: the upstream and downstream optical powers are normal, condition 3: the communication packet counter is not incremented, etc. are defined. The failure determination unit 55 determines whether a failure has occurred by comparing the information acquired by the batch processing unit 52a with the conditions of each failure scenario included in the determination condition list. The processing after being acquired as abnormal information is common to the processing in the above-mentioned management server 50.

[0053] FIG. 8 is a flowchart showing the switching process in the PON system 1A according to the modification example. As shown in FIG. 8, in normal times, each ONU 20 is initially activated with the operation-based OLT 30A (step S101), and the ONU 20 acquires the setting file of the ONU 20 for the OLT 30A prepared in advance. The ONU 20 operates based on the setting file.

[0054] Subsequently, the batch processing unit 52a of the main processing unit 52 of the management server 50A periodically acquires information on the operation OLT 30A (step S102) and information on the standby OLT 30B (step S103). The acquired information is stored in the database 51 (step S104).

[0055] Then, the failure determination unit 55 refers to the database 51, and compares the acquired information with a predetermined determination condition list (step S105). Based on the comparison result, the failure determination unit 55 identifies the OLT 30A in which a failure has occurred, and acquires the information related to the identified OLT 30A as abnormal information. Then, the failure determination unit 55 performs a switching operation of the output port so that the output destination of the optical switch 40 becomes the standby OLT 30B (step S106). Further, based on the setting information of the OLT 30B, a setting file 100 for the ONU 20 for the OLT 30B is generated. In this state, the ONU 20 is restarted (step S107), and the ONU 20 acquires a new setting file after the switching (the setting file 100 for the ONU 20 for the OLT 30B), and starts operating based on the setting file 100.

[0056] According to such a configuration, abnormal information can be appropriately and easily derived (acquired) based on a previously prepared determination condition list. And since the determination condition list includes various information in a plurality of failure scenarios, abnormal information can be appropriately and easily derived (acquired) by comparing with the conditions at the time of an actual failure occurrence.

Description of Reference Numerals

[0057] 1, 1A... PON system 20... ONU 30A, 30B, 30C... OLT 40... Optical switch 41, 42, 45, 46... Output port 50, 50A... Management server 51... Database (storage unit) 52... Main processing unit 52a…Batch processing unit (acquisition unit) 52b…WrbGUI application group 53…Configuration file generation unit (generation unit) 54…Switching control unit 55…Fault determination unit (acquisition unit) 100…Configuration file 501…PON system 550…Management server.

Claims

1. A storage unit that stores setting information for generating a setting file of an ONU corresponding to a plurality of OLTs; An acquisition unit that acquires abnormality information related to any one of the OLTs; A management server comprising: a generation unit that generates the setting file based on the setting information of another OLT so as to be able to switch from the OLT related to the abnormality information to another OLT.

2. The management server according to claim 1, wherein the setting information is wiring information of an optical switch provided between an ONU and a plurality of OLTs and configured to be able to switch an output destination OLT by switching an output port.

3. The management server according to claim 2, wherein the acquisition unit acquires, as the abnormality information, a signal notifying an abnormal state from an OLT in which a failure has occurred, or a signal from the optical switch that has detected a decrease in the optical level of the OLT in which a failure has occurred.

4. The management server according to claim 2, wherein the acquisition unit periodically acquires information from each OLT, compares the acquired information with a predetermined determination condition list, identifies an OLT in which a failure has occurred based on a comparison result, and acquires information related to the identified OLT as the abnormality information.

5. The management server according to claim 4, wherein the determination condition list includes various types of information in a plurality of failure scenarios.

6. The management server according to claim 2, further comprising a switching control unit that switches the output port so that the output destination of the optical switch becomes the other OLT when the setting file of the other OLT is generated by the generation unit.

7. A PON system comprising: a plurality of OLTs; and A management server that manages the plurality of OLTs, wherein The management server A storage unit that stores setting information for generating a setting file of an ONU corresponding to the plurality of OLTs; An acquisition unit that acquires abnormality information related to any one of the OLTs; A PON system comprising: a generation unit that generates the setting file based on the setting information of another OLT so as to be able to switch from the OLT related to the abnormality information to another OLT.

8. The PON system according to claim 7, wherein the OLT related to the abnormality information and the other OLT are OLTs of different models from each other.

9. A switching method executed by a management server that manages a plurality of OLTs, comprising: Acquiring abnormality information related to any one of the OLTs; Based on the setting information of the other OLT among the setting information for generating the corresponding ONU setting file for each pre-stored OLT so that switching from the OLT related to the abnormal information to another OLT becomes possible, generating the setting file. A switching method including this.

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