Network management device and method

Abstract

A network management device according to one embodiment includes: an extraction unit that, when a failure has occurred in a communication path of a communication network configuration, extracts, on the basis of the layer related to the communication path in which the failure has occurred, candidates for a detour path of a communication path related to provision of a service using the communication network configuration, within a range between the layer of one end of the communication path in which the failure has occurred and the layer of the other end; and an output unit that specifies, among the candidates extracted by the extraction unit, a communication path which is appropriate as the detour path, and outputs the communication path.

Description

Network management apparatus and method

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to a network management apparatus and method.

[0002] When a failure occurs in a large-scale system related to a communication network (sometimes simply referred to as a network (NW)), it is necessary to quickly identify the location of the failure and quickly understand the impact on services (see, for example, Patent Documents 1, 2, and 3).

[0003] Japanese Patent No. 6837022 Japanese Patent No. 7107158 Japanese Patent No. 6655524

[0004] With existing technologies, network resources are managed by layer, but it is difficult to grasp the impact at the service level. For example, impact assessment technology using NOIM (Network Operation Injected Model), a conventional network resource management technology, does not take into account communication path information (hereinafter sometimes referred to as route information) that indicates the order in which each service passes through the nodes on the constructed communication network as input information.

[0005] Furthermore, with conventional technology, it was necessary to acquire route information for all services in real time and handle a huge amount of route information, even in a network that changes every moment. Even if the relevant route information data was available, analyzing the data required a huge amount of time. This made it difficult to utilize route information in use cases involving large-scale system failures, where every second counts.

[0006] Because the above route information is treated as data on the same layer (plane), it cannot be used to detect failures that occur on different layers. For example, it was not possible to understand how the IP layer route for each service changes due to a physical failure and determine whether each service can be provided.

[0007] This invention was made in light of the above circumstances, and its purpose is to provide a network management device and method that can appropriately grasp the impact on services caused by communication failures.

[0008] A network management device according to one aspect of the present invention includes an extraction unit that, when a failure occurs in a communication path of a communication network configuration, extracts candidate detour routes for a communication path related to the provision of a service using the communication network configuration based on the hierarchical level of the communication path in which the failure occurred, within a range between the hierarchical level at one end of the communication path in which the failure occurred and the hierarchical level at the other end of the communication path in which the failure occurred, and an output unit that identifies and outputs a suitable communication path as the detour route from the candidates extracted by the extraction unit.

[0009] A network management method according to one aspect of the present invention is a method performed by a network management device, and includes the steps of: when a failure occurs in a communication path of a communication network configuration, an extraction unit of the network management device extracts candidate detour routes for a communication path related to the provision of a service using the communication network configuration based on the hierarchical level of the communication path where the failure occurred, within a range between the hierarchical level at one end of the communication path where the failure occurred and the hierarchical level at the other end; and an output unit of the network management device identifying and outputting a suitable communication path as the detour route from the candidates extracted by the extraction unit.

[0010] According to the present invention, it is possible to appropriately grasp the effect on services caused by the occurrence of a communication failure.

[0011] FIG. 1 is a diagram illustrating an example of an application of a network management device according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of processing executed by an embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a network configuration according to this embodiment. FIG. 4 is a diagram illustrating an example of creating route information according to this embodiment. FIG. 5 is a diagram illustrating an example of limiting targets for collecting route information according to this embodiment. FIG. 6 is a diagram illustrating an example of creating a detour route according to this embodiment. FIG. 7 is a diagram illustrating an example of limiting targets for collecting route information according to this embodiment. FIG. 8 is a flowchart illustrating an example of a processing procedure for route calculation under normal conditions by a network management device according to an embodiment of the present invention. FIG. 9 is a flowchart illustrating an example of a processing procedure for facility resource extraction by a network management device according to an embodiment of the present invention. FIG. 10 is a flowchart illustrating an example of a processing procedure for route recalculation by a network management device according to an embodiment of the present invention. FIG. 11 is a block diagram illustrating an example of the hardware configuration of a network management device according to an embodiment of the present invention.

[0012] An embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a diagram showing an application example of a network management device according to an embodiment of the present invention. As shown in Fig. 1, a network management device 100 according to an embodiment of the present invention includes a configuration information acquisition unit 10, a path information calculation unit 20, an influence range calculation unit 30, a resource extraction unit 40, and an output unit 50. Details of the processing performed by each unit will be described later.

[0013] FIG. 2 is a diagram illustrating an example of processing executed by an embodiment of the present invention. FIG. 2 shows a network extending from a GWR (gateway router) to an ER (edge ​​router) via a CR (core router). The edge router is a device that can be connected to a user terminal. The core router is a device that constitutes a relay network. The gateway router is a device that functions as a gateway to a service provider's server, etc.

[0014] In one embodiment of the present invention, the following processes (1) to (3) can be executed: (1) Creating route information in advance using network design information; (2) Limiting the targets for collecting route information based on the location of the failure and the extent of its ripple effect; and (3) Creating detour routes based on network design information and actual traffic information.

[0015] In (1) above, the normal route from the edge router to the gateway router is calculated based on the network system specifications, network design documents, configuration information, etc., and this route is then converted into a NOIM model in advance. By converting the normal route into a NOIM model in advance in this way, it becomes unnecessary to collect route information for normal locations, which makes it possible to significantly reduce the amount of data acquired in real time.

[0016] In the above (2), the area (marked b in Figure 2) where route information is redistributed and from which route information is collected is limited based on the failure location (marked a in Figure 2) and the impact range obtained by the impact assessment process in NOIM, which is the range affected by the failure. Network design information and actual traffic data such as mirror packets and traceroutes are acquired in this limited area. This limitation allows the data acquired in real time to be localized, significantly reducing the amount of acquired data. Furthermore, the above limitation can be applied universally, regardless of the network protocol.

[0017] In the above (3), route differences between before and after a failure are created based on the network design information and the acquired actual traffic data. As described above, by reducing the amount of acquired data, it is possible to improve the processing frequency and speed for creating route difference information. Therefore, since network route information can be updated frequently, it is possible to grasp the impact on each service provided on the network in real time, and the accuracy of impact assessment can be improved.

[0018] FIG. 3 is a diagram illustrating an example of a network configuration according to this embodiment. The example illustrated in FIG. 3 includes a first GWR (GWR1) and a second GWR (GWR2) in an upstream hierarchy, a first CR (CR1), a second CR (CR2), a third CR (CR3), and a fourth CR (CR4) in a hierarchy between the upstream and downstream, and a first ER (ER1), a second ER (ER2), a third ER (ER3), and a fourth ER (ER4) in a downstream hierarchy. The first and second GWRs are devices in an upstream hierarchy from the first and second GWRs and can communicate with a device that provides "Service A." The first CR is a device that provides "Service B." The first GWR can communicate with the second GWR and the first and third CRs. The second GWR is in communication with the first GWR and the second and fourth CRs.

[0019] The first CR can communicate with the first GWR, the second CR, and the first ER. The second CR can communicate with the second GWR, the first CR, and the second ER. The third CR can communicate with the first GWR, the fourth CR, and the third ER. The fourth CR can communicate with the second GWR, the third CR, and the fourth ER.

[0020] The first ER can communicate with the first CR and the second ER. The second ER can communicate with the second CR and the first ER. The third ER can communicate with the third CR and the fourth ER. The fourth ER can communicate with the fourth CR and the third ER.

[0021] The area indicated by the symbol a in Fig. 3, i.e., the area associated with the first and second CRs and the first and second ERs, is an area in which route information is redistributed using the same protocol, as is the area indicated by the symbol b in Fig. 3, i.e., the area associated with the third and fourth CRs and the third and fourth ERs.

[0022] In addition, in FIG. 3, the numbers "10," "30," and "100" shown on the routes of each GWR, CR, and ER indicate the cost level associated with setting each route, and in this embodiment, routes are selected so that the total cost is as low as possible.

[0023] Next, an example of "(1) Preliminary creation of route information using NW design information" in the network configuration shown in FIG. 3 will be described. Here, the creation of route information for downstream traffic will be described. FIG. 4 is a diagram illustrating an example of creation of route information according to this embodiment. The configuration information acquisition unit 10 of the network management device 100 acquires device configuration information including design parameters of the network configuration managed by the NOIM. The route information calculation unit 20 constructs a NW topology based on this acquired information.

[0024] The route information calculation unit 20 calculates a route under normal conditions, i.e., before a failure occurs, based on the costs associated with each route indicated in the device configuration information, such that the cost associated with each route from the start point to the end point is minimized.

[0025] The route information calculation unit 20 calculates the downstream traffic and the upstream traffic provided on the NW.

[0026] In the example shown in Fig. 4, it is assumed that the following first route (symbol a in Fig. 4), second route (symbol b in Fig. 4), third route (symbol c in Fig. 4), and fourth route (symbol d in Fig. 4) are calculated: First route: A route from a device that provides "Service A" to a first ER via a first GWR and a first CR Second route: A route from a device that provides "Service A" to a third ER via a first GWR and a third CR Third route: A route from a first CR that provides "Service B" to a first ER Fourth route: A route from a first CR that provides "Service B" to a third ER via a first GWR and a third CR The calculated routes are saved in the form of a NOIM model.

[0027] Next, an example of "(2) Limiting the collection targets of route information based on the location of the failure and the extent of the ripple effect" in the network configuration shown in Figure 3 will be described. Figure 5 is a diagram illustrating an example of limiting the collection targets of route information according to this embodiment. The impact extent calculation unit 30 specifies the extent of the ripple effect caused by the failure, which is specified by the NOIM impact assessment function. Here, as shown in Figure 5, it is assumed that a failure occurs on the path between the first GWR and the first CR (symbol e in Figure 5), and the extent consisting of each GWR, each CR, and each ER shown in Figure 5 is specified as the extent of the ripple effect.

[0028] The resource extraction unit 40 identifies the section affected by the ripple effect based on the Spec values ​​of the NOIM model, here the definition values ​​of the network tier, and narrows down the range of the ripple effect that corresponds to the tier of the path where the failure occurred. A tier with a relatively small Spec value indicates a tier that is relatively upstream in the network.

[0029] In the example shown in Figure 5, among the sections affected by the above-mentioned ripple effect, the range between the hierarchy of the first GWR and the hierarchy of the first CR related to the route where the failure occurred, i.e., the range consisting of the first and second GWRs and the first to fourth CRs (symbol f in Figure 5), is identified as the above-mentioned narrowed range.

[0030] The resource extraction unit 40 extracts basic paths that are within the narrowed-down range, that is, the Spec range, and are facility resources that can communicate. Here, it is assumed that the following paths are extracted as the basic paths: (1) the path between the first and second GWRs, (2) the path between the first GWR and the third CR, (3) the path between the second GWR and the second CR, (4) the path between the second GWR and the fourth CR, (5) the path between the first and second CRs, and (6) the path between the third and fourth CRs, among the paths in the range consisting of the first and second GWRs and the first to fourth CRs shown in Fig. 5 , excluding the path between the first GWR and the first CR where the failure occurred (symbol e in Fig. 5 ).

[0031] Next, an example of "(3) Creation of a detour route based on NW design information and actual traffic information" in the network configuration shown in Fig. 3 will be described. Fig. 6 is a diagram illustrating an example of creation of a detour route according to this embodiment. The route information calculation unit 20 calculates a detour route in the event of the failure from among the basic paths extracted within the range narrowed down in (2) above, based on the design information acquired in (1) above and the traffic calculated in (1) above.

[0032] In the example shown in Figure 6, a route (symbol a2 in Figure 6) from the first GWR via the second GWR and the second CR to the first CR is calculated as a route for "A service" that bypasses the route (symbol e in Figure 5) between the first GWR and the first CR where the failure has occurred in the narrowed range (symbol f in Figure 5), and a route (symbol d2 in Figure 6) from the first CR via the second CR, the second GWR, and the first GWR to the third CR is calculated as a route for "B service" that bypasses the route from the first CR via the first GWR to the third CR, which includes the route between the first GWR and the first CR (symbol e in Figure 5).

[0033] As described above, in this embodiment, a route that bypasses the route where the failure occurred is calculated from a range narrowed down according to the tier of the route where the failure occurred, so it is possible to determine the bypass route with a small amount of data and calculations.

[0034] When linking detour route data to the network configuration managed by NOIM, the detour route calculated from the narrowed down range can be targeted, thereby reducing the processing time required for linking.

[0035] Next, another example of "(2) Limiting the collection targets of route information based on the location of the failure and the range of the ripple effect" in the network configuration shown in Figure 3 will be described. Figure 7 is a diagram illustrating an example of limiting the collection targets of route information according to this embodiment. In the example shown in Figure 5, a failure occurs on the path between the first GWR and the first CR (symbol e in Figure 5), and the range consisting of each GWR, each CR, and each ER shown in Figure 5 is identified as the range affected by the ripple effect, and within this range, a narrowed range related to the tier of the path where the failure occurred is identified.

[0036] In contrast, in the example shown in FIG. 7 , the range (symbol f2 in FIG. 7 ) narrowed down to the range consisting of the first and second GWRs and the first and second CRs is identified as the range of extraction targets for the basic path related to the "A service" based on information about the range of redistribution of the route related to the provision of the "A service" (e.g., NW configuration information and NW routing table information) of the narrowed range (symbol f in FIG. 5 ) related to the hierarchical level of the route where the failure occurred in the example shown in FIG. 5 . The range (symbol f2 in FIG. 7 ) narrowed down to the range consisting of the first and second GWRs and the first and second CRs is identified as the range of extraction targets for the basic path related to the "A service." The range of extraction targets for the basic path related to the above-mentioned "B service" can also be identified in a similar manner. As described above, by narrowing down the range of extraction targets for the basic path according to the range of redistribution of the route from the service provider to the service destination, the amount of calculation required for subsequent processing can be further reduced.

[0037] 8 is a flowchart showing an example of a processing procedure for calculating a route under normal conditions by a network management device according to an embodiment of the present invention. The configuration information acquisition unit 10 of the network management device 100 acquires device configuration information including design parameters of the network configuration managed by the NOIM (S11).

[0038] The route information calculation unit 20 calculates the traffic of the network configuration based on the acquired results, calculates the routes for providing each service under normal conditions (S12), and outputs these calculation results as normal-condition route information (S13). This information is converted into a NOIM model and stored in the internal memory of the network management device 100.

[0039] 9 is a flowchart showing an example of a processing procedure for extracting facility resources by a network management device according to an embodiment of the present invention. When a failure occurs in the network configuration after the normal path information is output, the influence extent calculation unit 30 acquires information on the location of the failure (S21).

[0040] The impact range calculation unit 30 determines the range of impact caused by the above-mentioned failure in the network configuration (S22) using an existing method, for example, as described in Patent Document 2, and outputs this as impact range information (S23).

[0041] The resource extraction unit 40 receives the information on the failure location acquired in S21 and the information on the extent of influence grasped in S22 (S24). The resource extraction unit 40 acquires the calculation results of the traffic indicated by the normal route information output in S13, and calculates the extent of the recalculation of the route that bypasses the failure location based on the acquired results, the information on the failure location and the information on the extent of influence input in S24 (S25).

[0042] The resource extraction unit 40 extracts equipment resources within the range indicated by the calculation result in S25 (S26), and outputs them as acquisition target equipment resource information (S27).

[0043] 10 is a flowchart showing an example of a processing procedure for route recalculation by a network management device according to an embodiment of the present invention. The route information calculation unit 20 performs route recalculation (S31), which is calculation of a route that bypasses the failure point input in S24 within the range specified in S25.

[0044] If the route information calculation unit 20 can acquire traffic information for the current network configuration (Yes in S32), it acquires it as actual traffic information (S33). Based on the actual traffic information in S33, the route information calculation unit 20 performs transit section mapping to associate the NW devices through which packets actually flow (S34).

[0045] The route information calculation unit 20 calculates a route that connects the devices in the network through which the packet is flowing, which is the result of the passing section mapping in S34, and outputs route difference information that corrects the route recalculation result in S31 (S35).

[0046] The route information calculation unit 20 corrects the route recalculation result of S31 based on the route difference information output in S35 (S36), and creates a NOIM model from the corrected result. If the result of S32 is No, the route information calculation unit 20 creates a NOIM model from the route recalculation result of S31.

[0047] 11 is a block diagram showing an example of the hardware configuration of a network management device 100 according to an embodiment of the present invention. In the example shown in FIG. 11, the network management device 100 according to the embodiment is configured, for example, as a server computer or a personal computer, and has a hardware processor 111A such as a CPU. A program memory 111B, a data memory 112, an input / output interface 113, and a communication interface 114 are connected to this hardware processor 111A via a bus 115.

[0048] The communication interface 114 includes, for example, one or more wireless communication interface units, and enables transmission and reception of information to and from a communication network NW. As the wireless interface, for example, an interface that adopts a low-power wireless data communication standard such as a wireless LAN (Local Area Network) is used.

[0049] An input device 300 and an output device 400 attached to the network management device 100 and used by a user or the like are connected to the input / output interface 113. The input / output interface 113 receives operation data input by a user or the like via the input device 300, such as a keyboard, touch panel, touchpad, or mouse, and outputs output data to an output device 400, which may include a display device using a liquid crystal or organic electroluminescence (EL) display, for display. The input device 300 and the output device 400 may be devices built into the network management device 100, or may be input devices and output devices of other information terminals that can communicate with the network management device 100 via the network NW.

[0050] The program memory 111B is a non-transitory tangible storage medium that is a combination of a non-volatile memory that can be written to and read from at any time, such as a hard disk drive (HDD) or a solid state drive (SSD), and a non-volatile memory such as a read only memory (ROM), and stores programs necessary to execute various control processes, etc., according to one embodiment.

[0051] The data memory 112 is a tangible storage medium that is a combination of, for example, the above-mentioned nonvolatile memory and a volatile memory such as RAM (Random Access Memory), and is used to store various data acquired and created during various processing steps.

[0052] A network management device 100 according to an embodiment of the present invention may be configured as a data processing system or information processing device having a software-based processing function unit. A storage system used as a work memory or the like by the network management device 100 may be configured using the data memory 112 shown in FIG. 11 . However, these configured storage areas are not essential components within the network management device 100, and may be areas provided in a storage system such as an external storage medium such as a USB (Universal Serial Bus) memory, or a database server located in the cloud.

[0053] The processing function unit can be realized by having the hardware processor 111A read and execute a program stored in the program memory 111B, but the processing function unit may also be realized in various other forms, including an integrated circuit such as an application specific integrated circuit (ASIC) or a field-programmable gate array (FPGA).

[0054] The methods described in each embodiment may be stored as a program (software means) that can be executed by a computer on a recording medium such as a magnetic disk (e.g., a floppy disk, a hard disk, etc.), an optical disk (e.g., a CD-ROM, a DVD, an MO, etc.), or a semiconductor memory (e.g., a ROM, a RAM, a flash memory, etc.), or may be transmitted and distributed via a communication medium. The program stored on the medium also includes a configuration program that configures the software means (including not only executable programs but also tables and data structures) that the computer executes. The computer that realizes this device reads the program stored on the recording medium and, in some cases, configures the software means using the configuration program, and executes the above-described processing by having the operation controlled by this software means. The term "recording medium" as used herein is not limited to a storage medium for distribution, but also includes a storage medium such as a magnetic disk or semiconductor memory installed inside the computer or in a device connected via a network.

[0055] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

[0056] REFERENCE SIGNS LIST 100: Network management device 10: Configuration information acquisition unit 20: Path information calculation unit 30: Influence range calculation unit 40: Resource extraction unit 50: Output unit

Claims

1. A network management device comprising: an extraction unit that, when a failure occurs in a communication path of a communication network configuration, extracts candidates for detour routes of a communication path related to the provision of a service using the communication network configuration based on a hierarchical level related to the communication path where the failure occurred, within a range between a hierarchical level at one end and a hierarchical level at the other end of the communication path where the failure occurred; and an output unit that identifies and outputs a communication path suitable as the detour route from the candidates extracted by the extraction unit.

2. A network management device as described in claim 1, further comprising an identification unit that identifies a failure impact range in the communication network configuration due to the occurrence of a failure in the communication path, wherein the extraction unit extracts candidates for the detour route in the identified failure impact range within a range between a hierarchical level at one end and a hierarchical level at the other end of the communication path where the failure has occurred.

3. A network management device as described in claim 1, further comprising a calculation unit that calculates a communication path used to provide the service before the failure occurred, wherein the extraction unit extracts candidates for the detour route in the communication path indicated by the information calculated by the calculation unit when the failure occurs within a range between the hierarchical level at one end and the hierarchical level at the other end of the communication path where the failure occurred.

4. A method performed by a network management device, comprising: an extraction unit of the network management device extracts, when a failure occurs in a communication path of a communication network configuration, candidates for detour routes for a communication path related to the provision of a service using the communication network configuration, based on the hierarchical level of the communication path in which the failure occurred, within a range between the hierarchical level at one end and the hierarchical level at the other end of the communication path in which the failure occurred; and an output unit of the network management device identifies and outputs a communication path suitable as the detour route from among the candidates extracted by the extraction unit.

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