Diagnosis system, diagnostic device and diagnosis method

Abstract

To efficiently execute diagnosis of a network of a mesh structure.SOLUTION: A diagnosis system is a network diagnosis system which includes transmission nodes, reception nodes, and a diagnostic device to transmit a frame from the transmission node to the reception node by using a plurality of paths which are respectively independent, the transmission node transmits a plurality of frames with the same reception node as a destination to the plurality of paths regardless of whether or not a failure occurs in a portion of the plurality of paths, the reception node respectively measures arrival time of the plurality of frames received from the same transmission node on the basis of a timer, and notifies the diagnostic device of a measurement result, and the diagnostic device executes processing for diagnosing time required to reconstruct a communication path of a network and the performance of the reconstructed network when a pseudo failure occurs on the basis of the measurement result.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a diagnostic system, a diagnostic device, and a diagnostic method. [Background technology]

[0002] Network paths are made redundant in preparation for network equipment failures, etc. For example, in Patent Document 1, two Ethernet switches are connected by two lines, and under normal circumstances, communication is carried out using one of the lines. When the line abnormality detection circuit of the Ethernet switch detects that an abnormality has occurred in the line in use, the line is changed to the other line and the path is switched.

[0003] In Patent Document 1, it takes a finite amount of time for the line abnormality detection circuit to detect an abnormality, and it also takes time to switch the path, which causes interruptions in information transmission.

[0004] For example, Non-Patent Document 1 addresses the issues of Patent Document 1 above. In Non-Patent Document 1, a redundant ring route is provided, making the communication route redundant. As a result, in Non-Patent Document 1, communication frames are sent to the destination from both sides of the ring, so that even if an abnormality occurs in the route on one side, the communication frame from the other side arrives at the destination without delay, preventing interruptions in information transmission. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-45399 [Non-patent literature]

[0006] [Non-Patent Document 1] Industrial Ethernet Rings: PROFINet MRP and MRPD [Retrieved February 1, 2024], Internet <URL:https: / / www.hms-networks.com / news-and-insights / blog / posts / iot-blog / 2018 / 06 / 11 / industrial-ethernet-rings-profinet-mrp-and-mrpd> Summary of the Invention [Problem to be solved by the invention]

[0007] In the ring topology described in Non-Patent Document 1, propagation delay time occurs at each node, making it difficult to apply to large-scale systems with a large number of nodes. Also, general Ethernet system topologies often use mesh structures, and ring topologies reduce the degree of freedom in system construction.

[0008] For this reason, even when a mesh topology is used, it is desirable to diagnose the network so that interruptions in information transmission do not occur.

[0009] Regarding network diagnosis, it is possible to check the route that a communication frame is traveling by obtaining information from multiple network switches, but this requires a complicated procedure and is not practical. Also, if a failure occurs somewhere in the network, the route of the communication frame in the mesh structure will be reconstructed and a different route will be taken, but it is extremely difficult to confirm whether the mesh topology has enough redundancy to enable the reconstruction, or to grasp the loss time required for the reconstruction, or the impact of communication congestion caused by the reconstruction.

[0010] In one aspect, an object of the present invention is to provide a diagnostic system, a diagnostic device, and a diagnostic method that can efficiently diagnose a mesh structure network. [Means for solving the problem]

[0011] One aspect of the diagnostic system is a network diagnostic system that has a transmitting node, a receiving node, and a diagnostic device, and transmits frames from the transmitting node to the receiving node using multiple independent routes, where the transmitting node transmits multiple frames addressed to the same receiving node over multiple routes regardless of whether a failure has occurred in some of the multiple routes, the receiving node measures the arrival time of each of the multiple frames received from the same transmitting node based on a timer and notifies the diagnostic device of the measurement results, and the diagnostic device performs processing based on the measurement results to diagnose the time required to reconstruct the network communication routes when a failure occurs and the performance of the network after reconstruction.

[0012] One aspect of the diagnostic device includes a collection unit that collects measurement results of arrival times from receiving nodes that receive multiple frames transmitted from the same transmitting node, regardless of whether a failure has occurred in some of the multiple independent paths included in the network, and a diagnostic processing unit that, based on the measurement results, diagnoses the time required to reconstruct the communication paths of the network when a failure has occurred and the performance of the network after the reconstruction.

[0013] One aspect of the diagnostic method is a method for diagnosing a network that has a transmitting node, a receiving node, and a diagnostic device, and that transmits frames from the transmitting node to the receiving node using multiple independent routes, in which the transmitting node transmits multiple frames addressed to the same receiving node over the multiple routes, regardless of whether a failure has occurred in some of the multiple routes, the receiving node measures the arrival time of each of the multiple frames received from the same transmitting node based on a timer and notifies the diagnostic device of the measurement results, and the diagnostic device diagnoses, based on the measurement results, the time required to reconstruct the communication routes of the network when a failure has occurred and the performance of the network after the reconstruction. Execute the process. [Effects of the Invention]

[0014] According to one embodiment, diagnosis of a mesh network can be efficiently performed. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram illustrating a network with a double tree structure. [Figure 2] FIG. 1 is a diagram illustrating a network having a mesh structure. [Figure 3] 1 is a diagram illustrating a diagnostic system according to an embodiment of the present invention. [Figure 4] FIG. 10 is a diagram for explaining processing by the diagnostic device. [Figure 5] FIG. 10 is a diagram showing an example of the data structure of a first measurement result table. [Figure 6] FIG. 10 is a diagram showing an example of the data structure of a second measurement result table. [Figure 7] FIG. 10 is a diagram illustrating an example of a data structure of a system vulnerability table. [Figure 8] 1 is a functional block diagram showing the configuration of a diagnostic device according to an embodiment of the present invention; [Figure 9] 3 is a flowchart showing a processing flow of the diagnostic device of the present embodiment. [Figure 10] FIG. 1 is a diagram illustrating an example of a plurality of logically independent networks. [Figure 11] FIG. 2 is a diagram illustrating an example of a hardware configuration. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the diagnostic system, diagnostic device, and diagnostic method disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments. Furthermore, the same elements are given the same reference numerals, redundant explanations are omitted as appropriate, and the respective embodiments can be combined as appropriate within a range that does not cause inconsistency.

[0017] (Embodiment) (Mesh structure network) Before describing this embodiment, an example of a network related to a mesh structure will be described. Fig. 1 is a diagram for explaining a network with a double tree structure. For example, a network N1 includes DCNs (Distributed Compute Nodes) 10a, 10b, 10c, 10d, and 10e, DPX adapters 11a, 11b, 11c, 11d, and 11e, HUBs 20 and 30, and a setting unit 40.

[0018] The DCNs 10a to 10e are connected to DPX adapters 11a to 11e, respectively. The DPX adapters 11a to 11e are connected to HUBs 20 and 30, respectively. The DCNs 10a to 10e are collectively referred to as "DCN 10" where appropriate. The DPX adapters 11a to 11e are collectively referred to as "DPX adapter 11" where appropriate.

[0019] The DCN 10 outputs data received from, for example, an input device, a control device, or the like to the DPX adapter 11.

[0020] When the DPX adapter 11 receives data from the DCN 10, it transmits communication frames to multiple routes. When the DPX adapter 11 receives communication frames from multiple routes, it selects one of the communication frames and outputs the data of the selected communication frame to the DCN 10.

[0021] HUB20 and 30 are network switches. Network N1 includes a communication path that passes through HUB20 and a communication path that passes through HUB30. A setting unit 40 is connected to HUB20. The setting unit 40 performs various settings on DCN10 and the like via HUB20. Unlike communication between DCNs 10, high reliability is not required for communication between the setting unit 40 and DCN10. For example, if HUB20 fails, the setting unit 40 can be connected to HUB30 instead of HUB20.

[0022] For example, when the DPX adapter 11b receives data from the DCN 10b, it generates two identical communication frames. The DPX adapter 11b transmits one communication frame to the DPX adapter 11c via the HUB 20, and transmits the other communication frame to the DPX adapter 11c via the HUB 30.

[0023] When the DPX adapter 11c receives two communication frames via multiple routes, it selects one of the communication frames and outputs the data of the selected communication frame to the DCN 10c.

[0024] The network N1 described in Figure 1 has advantages over a ring configuration. For example, the advantages include: (1) greater flexibility and intuitiveness in wiring than a ring configuration; (2) no disturbances when inserting or removing communication nodes; (3) no risk of problems caused by simultaneous disconnection of two points on the ring; and (4) no need for the ring master function required by MRP (Media Redundancy Protocol). Note that while Figure 1 describes the case where there are two communication paths (double tree), there can also be n paths (n is a natural number greater than or equal to 3). For example, with a triple tree, hubs can be replaced one by one without sacrificing reliability.

[0025] The HUBs 20 and 30 described in Fig. 1 may be a network in which a plurality of network switches are connected in a mesh pattern, as shown in Fig. 2. Fig. 2 is a diagram for explaining a mesh network.

[0026] 2, for example, network N2 includes DCNs 10a to 10e and DPX adapters 11a to 11e. Network N2 includes SWs 20-1, 20-2, 20-3, 20-4, 20-5, and 20-6. Network N2 includes SWs 30-1, 30-2, 30-3, 30-4, 30-5, and 30-6.

[0027] The explanation for DCNs 10a to 10e and DPX adapters 11a to 11e is the same as the explanation for DCNs 10a to 10e and DPX adapters 11a to 11e given in Figure 1. SW20-1 to 20-6 and SW30-1 to 30-6 are network switches (Ethernet switches) or the like. Although SW20-1 to SW20-6 and SW20-1 to SW20-6 are drawn completely symmetrically in Figure 2, this is not necessarily the case. The SW20 system may use more switches than the SW30 system, resulting in an asymmetric system in which information is transmitted via more stages.

[0028] For example, DPX adapters 11a and 11b are connected to SW20-1 and 30-1, and DPX adapters 11c, 11d, and 11e are connected to SW20-3 and 30-3.

[0029] SW20-1 to 20-6 perform data communication using a predetermined communication protocol and establish optimal path information in advance. SW20-1 to 20-6 transmit communication frames based on the established path information. For example, when SW20-1 receives a communication frame addressed to DPX adapter 11c from DPX adapter 11b, the communication frame reaches DPX adapter 11c via SW20-1, 20-2, and 20-3.

[0030] When a failure occurs in any of the switches, the switches 20-1 to 20-6 reconstruct the path information.

[0031] SW30-1 to 30-6 perform data communication using a predetermined communication protocol and establish optimal path information in advance. SW30-1 to 30-6 transmit communication frames based on the established path information. For example, when SW30-1 receives a communication frame addressed to DPX adapter 11c from DPX adapter 11b, the communication frame reaches DPX adapter 11c via SW30-1, 30-2, and 30-3.

[0032] When a failure occurs in any of the switches, the switches 30-1 to 30-6 reconstruct the path information.

[0033] In the example shown in FIG. 2, SW20-1 to 20-6 and SW30-1 to 30-6 are shown, but other SWs may also be included.

[0034] The double-tree structure network and the mesh structure network have been described above.

[0035] (Diagnostic System) Next, an example of a diagnostic system according to this embodiment will be described. Fig. 3 is a diagram showing the diagnostic system according to this embodiment. As shown in Fig. 3, the diagnostic system S1 includes DCNs 10a to 10e, DPX adapters 51a, 51b, 50c, 50d, and 51e, SWs 20-1 to 20-6, and 30-1 to 30-6, and a diagnostic device 100.

[0036] DCNs 10a to 10e are connected to DPX adapters 51a to 51e, respectively. For example, DPX adapters 51a and 51b are connected to SW20-1 and 30-1. DPX adapters 51c, 51d, and 51e are connected to SW20-3 and 30-3. Although the connection relationships are not shown in FIG. 3, diagnostic device 100 is connected to SW20 or SW30, or in some cases both (SW20 and SW30).

[0037] The network constructed by SW20-1 to 20-6 and the network constructed by SW30-1 to 30-6 described in Fig. 3 are depicted as physically independent networks. For example, the network of diagnostic system S1 is a double-tree network. Note that as long as the network constructed by SW20-1 to 20-6 and the network constructed by SW30-1 to 30-6 are independent, they may be physically independent or logically independent.

[0038] The DCNs 10a to 10e will be collectively referred to as "DCN 10" where appropriate. The DPX adapters 51a to 51e will be collectively referred to as "DPX adapter 51" where appropriate.

[0039] SW20-1 to 20-6 perform data communication using a predetermined communication protocol and establish optimal path information in advance. SW20-1 to 20-6 transmit communication frames based on the established path information. For example, when SW20-1 receives a communication frame addressed to DPX adapter 51c from DPX adapter 51b, the communication frame reaches DPX adapter 51c via SW20-1, 20-2, and 20-3.

[0040] When a failure occurs in any of the SWs 20-1 to 20-6, the SWs 20-1 to 20-6 execute data communication and reconstruct the path information.

[0041] SW30-1 to 30-6 perform data communication using a predetermined communication protocol and establish optimal path information in advance. SW30-1 to 30-6 transmit communication frames based on the established path information. For example, when SW30-1 receives a communication frame addressed to DPX adapter 51c from DPX adapter 51b, the communication frame reaches DPX adapter 51c via SW30-1, 30-2, and 30-3.

[0042] When a failure occurs in any of the switches SW30-1 to SW30-6, SW30-1 to SW30-6 execute data communication and reconstruct the path information.

[0043] The DCN 10 is a communication node that requires high reliability in data exchange. For example, it outputs data received from an input device, a control device, etc. to the DPX adapter 51.

[0044] When the DPX adapter 51 receives data from the DCN 10, it transmits the same communication frame to multiple routes. In the example shown in Fig. 3, the multiple routes include a route established by SW20-1 to 20-6 and a route established by SW30-1 to 30-6. When the DPX adapter 51 receives a communication frame from multiple routes, it selects one of the communication frames and outputs the data of the selected communication frame to the DCN 10.

[0045] In the following description, a communication frame that uses a route established by SW20-1 to 20-6 will be referred to as a "first communication frame." A communication frame that uses a route established by SW30-1 to 30-6 will be referred to as a "second communication frame." When there is no need to distinguish between the first communication frame and the second communication frame, they will be referred to as communication frames.

[0046] The DPX adapter 51 has a timer that measures the time difference between the arrival of communication frames received from multiple routes. The DPX adapter 51 discloses (transmits) to the diagnostic device 100 the measurement result measured by the timer.

[0047] Diagnostic device 100 is a device that executes network diagnosis for diagnostic system S1. Fig. 4 is a diagram for explaining the processing of the diagnostic device. Diagnostic device 100 selects SWs 20-1 to 20-6 and SWs 30-1 to 30-6 in which a pseudo-failure will occur and a port in each SW in which a failure will occur.

[0048] 4 shows a case where SW30-2 is selected as the SW in which a pseudo-failure is to be generated by diagnostic device 100. Also, as an example, a case where DPX adapter 51b transmits a communication frame to DPX adapter 51c is shown.

[0049] For example, diagnostic device 100 executes a process of generating a pseudo-failure and a process of collecting arrival time difference information.

[0050] The process of diagnostic device 100 causing a pseudo-failure will be described. For example, diagnostic device 100 transmits a control signal to SW30-2 to cause a pseudo-failure. Specifically, a specific port of SW30-2 is disabled. As a result, for example, the path between SW30-2 and SW30-3 is blocked. When SW30-1 to 30-6 detect the path blocking, they reconstruct the path information.

[0051] The following describes the process of collecting arrival time difference information by diagnostic device 100. Here, the description will be given taking as an example a case where DPX adapter 51b transmits a communication frame to DPX adapter 51c, and DPX adapter 51c discloses the measurement result to diagnostic device 100.

[0052] For example, DPX adapter 51b transmits communication frames to SW20-1 and SW30-1. The transmitting DPX adapter 51 is an example of a “transmitting node.” In the following description, the transmitting DPX adapter will be referred to as a transmitting node where appropriate.

[0053] The DPX adapter 51c receives the first communication frame and the second communication frame from the DPX adapter 51b, measures the time difference between the time when the first communication frame is received and the time when the second communication frame is received, and discloses the measurement result to the diagnostic device 100. In addition to the time difference information, the measurement result also includes information identifying the transmitting node that transmitted the communication frame and the receiving node (its own DPX adapter 51c). The receiving DPX adapter 51 is an example of a "receiving node." In the following description, the receiving DPX adapter will be referred to as the receiving node where appropriate. Note that if the DPX adapter 51c does not receive either the first communication frame or the second communication frame, it sets the measurement result to time-up.

[0054] Before generating a pseudo fault, diagnostic device 100 acquires a measurement result (pre-fault setting arrival time difference) from DPX adapter 51c, and registers the relationship between the transmitting node (for example, DPX adapter 51b), the receiving node (DPX adapter 51c), and the pre-fault setting arrival time difference in first measurement result table 141. Similarly, diagnostic device 100 repeatedly executes the process of registering the relationship between the transmitting node, receiving node, and pre-fault setting arrival time difference in first measurement result table 141 every time it acquires a measurement result from another receiving node.

[0055] 5 is a diagram showing an example of the data structure of the first measurement result table. As shown in Fig. 5, the first measurement result table 141 registers the arrival time difference before fault setting for a pair of a sending node and a receiving node. For example, it shows that the arrival time difference before fault setting for a pair of a sending node 51a (similar to the DPX adapter 51a) and a receiving node 51c (similar to the DPX adapter 51c) is "TDac0".

[0056] Next, after generating a pseudo-failure, diagnostic device 100 acquires a measurement result (alternative path construction time) from DPX adapter 51c and registers the relationship between the transmitting node (for example, DPX adapter 51b), the receiving node (DPX adapter 51c), and the alternative path construction time in second measurement result table 142. Similarly, diagnostic device 100 acquires measurement results from other receiving nodes and repeatedly executes the process of registering the relationship between the transmitting node, the receiving node, and the alternative path construction time in second measurement result table 142.

[0057] Furthermore, after generating the pseudo-fault and after the path information has been reconstructed, diagnostic device 100 acquires the measurement result (post-fault setting arrival time difference) from DPX adapter 51c, and further registers the relationship between the transmitting node (for example, DPX adapter 51b), the receiving node (DPX adapter 51c), and the post-fault setting arrival time difference in second measurement result table 142. Similarly, diagnostic device 100 acquires measurement results from other receiving nodes, and repeatedly executes the process of registering the relationship between the transmitting node, the receiving node, and the post-fault setting arrival time difference in second measurement result table 142.

[0058] 6 is a diagram showing an example of the data structure of the second measurement result table. As shown in FIG. 6, the second measurement result table 142 registers the post-fault setting arrival time difference and the alternative path construction time for a pair of a sending node and a receiving node. For example, it shows that the alternative path construction time for a pair of a sending node 51a (similar to the DPX adapter 51a) and a receiving node 51c (similar to the DPX adapter 51c) is "TRac" and the post-fault setting arrival time difference is "TDac1".

[0059] The diagnostic device 100 executes a diagnostic process based on the first measurement result table 141 and the second measurement result table 142, and registers the diagnostic results in the system vulnerability table 143. For example, when the alternative route construction time is long (longer than a predetermined time) and a failure occurs in the selected SW, the diagnostic device 100 diagnoses that "alternative route construction is impossible" or "alternative route construction time is too long." More specifically, when a time-out is set in the measurement result from the receiving node, the diagnostic device 100 diagnoses that an alternative route construction is impossible if the time-out continues, and diagnoses that an alternative route construction time is too long if the time-out continues for a long time (i.e., the alternative route construction time is long).

[0060] Furthermore, when the difference between the arrival time difference before the fault is set and the arrival time difference after the fault is set is large (larger than a preset threshold), the diagnostic device 100 diagnoses that there is an excessive change in performance after the establishment of the alternative path. The diagnostic device 100 associates the sending node, receiving node, and diagnostic result and registers them in the system vulnerability table 143. The diagnostic device 10 then cancels the pseudo-fault.

[0061] Diagnostic device 100 repeatedly executes the above process while changing the SW and port in which a pseudo-failure occurs.

[0062] 7 is a diagram showing an example of the data structure of the system vulnerability table. As shown in FIG. 7, the system vulnerability table 143 comprehensively sets the diagnosis results when a pseudo-failure is caused in each SW. For example, when a failure occurs in SW20-2 (Port 4), it is shown that the pair of the sending node 51a (similar to the DPX adapter 51a) and the receiving node 51d (similar to the DPX adapter 51d) is diagnosed as having an excessive time for establishing an alternative path. Furthermore, when a failure occurs in SW20-2 (Port 4), it is shown that the pair of the sending node 51a (similar to the DPX adapter 51a) and the receiving node 51d (similar to the DPX adapter 51d) is diagnosed as having an excessive change in performance after establishing an alternative path.

[0063] (Functional configuration of diagnostic device 100) Next, a configuration example of the diagnostic device 100 according to this embodiment will be described. FIG. 8 is a functional block diagram showing the configuration of the diagnostic device according to this embodiment. As shown in FIG. 8, the diagnostic device 100 has a communication unit 110, an input unit 120, a display unit 130, a storage unit 140, and a control unit 150. Note that the functional units of the diagnostic device 100 are not limited to those shown in the figure, and the diagnostic device 100 may have other functional units. Note that the diagnostic device 100 may be realized by multiple server computers.

[0064] The communication unit 110 executes data communication with the DPX adapters 51a to 51e, SWs 20-1 to 20-6, and 30-1 to 30-6.

[0065] The input unit 120 inputs various types of information to the control unit 150 of the diagnostic device 100. The input unit 120 is a keyboard, a mouse, a touch panel, or the like.

[0066] The display unit 130 displays information output from the control unit 150 of the diagnostic device 100 .

[0067] The storage unit 140 stores a first measurement result table 141, a second measurement result table 142, and a system vulnerability table 143. The storage unit 140 is realized by a memory, a hard disk, or the like.

[0068] The explanations regarding the first measurement result table 141, the second measurement result table 142, and the system vulnerability table 143 are the same as those given in FIGS.

[0069] The control unit 150 is a processing unit that controls the entire diagnostic device 100, and is realized by, for example, a processor. The control unit 150 includes a fault occurrence processing unit 151, a collection unit 152, and a diagnostic processing unit 153.

[0070] The failure occurrence processing unit 151 selects a SW (and a port) in which a failure is to be simulated, and transmits a control signal for causing a failure to the selected SW. After completing the diagnosis related to the SW in which the failure is simulated, the failure occurrence processing unit 151 cancels the simulated failure of the SW and switches the SW in which the failure is to be simulated.

[0071] The failure occurrence processing unit 151 may randomly select a SW in which to cause a pseudo-failure, or may select a SW according to priority. For example, it is assumed that the priority of each SW is set in advance.

[0072] Other processes executed by the failure occurrence processing unit 151 are similar to the process of pseudo-inducing a failure, which has been described with reference to FIG.

[0073] The collection unit 152 acquires measurement results (arrival time differences before fault setting) from each receiving node before a pseudo fault occurs in the SW, and registers the relationship between the transmitting node, the receiving node, and the arrival time differences before fault setting in the first measurement result table 141.

[0074] After a pseudo-failure occurs in the SW, the collection unit 152 acquires measurement results (alternative path construction time) from each receiving node, and registers the relationship between the sending node, the receiving node, and the alternative path construction time in the second measurement result table 142.

[0075] After the pseudo-failure is generated and the path information is reconstructed, the collection unit 152 acquires the measurement results (arrival time difference after fault setting) from each receiving node, and further registers the relationship between the transmitting node, the receiving node, and the arrival time difference after fault setting in the second measurement result table 142.

[0076] The diagnostic processing unit 153 executes diagnostic processing based on the first measurement result table 141 and the second measurement result table 142, and registers the diagnostic results in the system vulnerability table 143.

[0077] For example, the diagnostic processing unit 153 selects a pair of a sending node and a receiving node, and if the alternative path construction time for the selected pair is long (longer than a predetermined time) and a failure occurs in the SW (and port), it diagnoses that the alternative path construction is impossible or that the required time is excessive. For example, if a time-out is set in the measurement result, the diagnostic processing unit 153 diagnoses that the alternative path construction is impossible, and if the alternative path construction time is long, it diagnoses that the alternative path construction time is excessive.

[0078] If the difference between the arrival time difference before the fault is set and the arrival time difference after the fault is set is large (larger than a preset threshold), the diagnosis processing unit 153 diagnoses that there is an excessive change in performance after the establishment of the alternative path.

[0079] The collection unit 152 and the diagnostic processing unit 153 repeatedly execute the above process every time the SW (and port) in which the pseudo-failure occurs is switched. The diagnostic processing unit 153 may output the diagnostic results registered in the system vulnerability table 143 to the display unit 130 for display.

[0080] (Processing flow) Next, a description will be given of the processing flow of the diagnostic device 100 of this embodiment. Fig. 9 is a flowchart showing the processing flow of the diagnostic device of this embodiment. As shown in Fig. 9, the failure occurrence processing unit 151 of the diagnostic device 100 selects a SW in which to cause a pseudo failure from SWs included in the communication path (step S101).

[0081] The collection unit 152 of the diagnostic device 100 acquires the pre-fault setting arrival time difference before the pseudo-fault is generated, and registers it in the first measurement result table 141 (step S102). The fault generation unit 151 of the diagnostic device 100 transmits a control signal to the selected SW to generate a pseudo-fault (step S103).

[0082] The collection unit 152 acquires the alternative path construction time and registers it in the second measurement result table 142 (step S104). The collection unit 152 acquires the post-fault setting arrival time difference and registers it in the second measurement result table 142 (step S105).

[0083] The diagnostic processing unit 153 executes a diagnostic process based on the first measurement result table 141 and the second measurement result table 142, and registers the diagnostic result in the system vulnerability table 143 (step S106). The diagnostic process executed by the diagnostic processing unit 153 in step S106 is the same as that described above.

[0084] The failure occurrence processing unit 151 removes the failure of the SW that caused the pseudo failure (step S107), and the process proceeds to step S101.

[0085] (effect) Next, the effects of the diagnostic system S1 according to this embodiment will be described. In the diagnostic system S1, a transmitting node transmits multiple communication frames addressed to the same receiving node via multiple routes after a simulated failure occurs on one of the multiple routes. The receiving node measures the arrival time of each of the multiple frames received from the same transmitting node based on a timer, and notifies the diagnostic device 100 of the measurement results. Based on the measurement results, the diagnostic device 100 diagnoses the time required to reconstruct the communication routes of the network when a simulated failure occurs, and the performance of the network after the reconstruction. This allows for efficient diagnosis of mesh-structured networks.

[0086] Furthermore, according to the diagnostic system S1, the diagnostic device 100 selects some nodes included in multiple routes and further executes a process of generating pseudo-faults in the selected some nodes (SWs). This makes it possible to easily diagnose the impact of faults that occur in each node.

[0087] Furthermore, according to the diagnostic system S1, the receiving node notifies the diagnostic device 100 of the period during which some of the frames from the same transmitting node do not arrive after a pseudo-failure occurs on one of the multiple routes as the alternative route construction time. The diagnostic device 100 diagnoses the alternative route construction time as the time required to reconstruct the communication route of the network when the pseudo-failure occurs. This makes it easy to identify the time from the occurrence of the failure until the communication route is reconstructed.

[0088] The receiving node notifies the diagnostic device of the difference in arrival time of multiple frames received from the same transmitting node as the pre-fault setting arrival time difference before a pseudo-fault occurs on some of the multiple routes, and notifies the diagnostic device 100 of the difference in arrival time of multiple frames received from the same transmitting node after a pseudo-fault occurs on some of the multiple routes and the route information has been reconstructed as the post-fault setting time difference.The diagnostic device diagnoses the difference between the arrival time of a frame through the network before the reconstructed network and the arrival time of a frame through the network after the reconstructed network based on the pre-fault setting arrival time difference and the post-fault setting time difference.This makes it possible to identify the performance after the communication route has been reconstructed due to the occurrence of a fault.

[0089] Furthermore, according to the diagnostic system S1, if a receiving node does not receive frames from some of the multiple routes, it notifies the diagnostic device 100 of information that the frame is not being received from some of the routes. This makes it possible to identify routes that become unavailable due to the occurrence of a fault. Note that the pseudo-fault settings are performed comprehensively for the entire network system. In this case, the explanation up to this point has been about setting a pseudo-fault in one location at a time, and then canceling the setting before setting the next location. However, multiple faults may also be simulated. In other words, simultaneous settings in multiple locations are also acceptable. However, setting faults simultaneously across both independent networks (in the case of two independent systems) may prevent signals from being transmitted from the transmitting node to the receiving node, so such multiple settings should be avoided.

[0090] (Other network configurations) For example, in the example described in Figure 3 etc., the network constructed by SW20-1 to 20-6 and the network constructed by SW30-1 to 30-6 are described as physically independent networks, but as long as the network constructed by SW20-1 to 20-6 and the network constructed by SW30-1 to 30-6 are independent, they may be physically independent or logically independent.

[0091] Figure 10 is a diagram showing an example of multiple logically independent networks. The network shown in Figure 8 uses virtual LAN (VLAN) technology to configure multiple logically independent networks. For example, one VLAN connects DPX adapter 11b to SW20-1, and another VLAN connects DPX adapter 11b to SW30-1. One VLAN connects DPX adapter 11c to SW20-3, and another VLAN connects DPX adapter 11c to SW30-3. The topology shown in Figure 10 can be realized by using the Multiple Spanning Tree Protocol (MSTP) defined in IEC / IEEE 60802 and a network switch that supports it.

[0092] (Hardware) Next, an example of the hardware configuration of diagnostic device 100 will be described. Fig. 11 is a diagram illustrating an example of the hardware configuration. As shown in Fig. 11, diagnostic device 100 has a communication device 6a, an HDD (Hard Disk Drive) 6b, a memory 6c, and a processor 6d. Furthermore, the components shown in Fig. 11 are connected to each other via a bus or the like.

[0093] The communication device 6a communicates with the DPX adapter 11 of the diagnostic system S1, SW20-1 to 20-6, SW30-1 to 30-6, etc. The HDD 6b stores programs and DBs that operate the functions shown in FIG.

[0094] The processor 6d reads out a program that executes the same processes as those of the processing units shown in Fig. 8 from the HDD 6b or the like and loads it into the memory 6c, thereby operating a process that executes the functions described in Fig. 8 or the like. For example, this process executes the same functions as those of the processing units included in the diagnostic device 100. Specifically, the processor 6d executes a process that executes the same processes as those of the fault occurrence processing unit 151, the collection unit 152, the diagnostic processing unit 153, and the like.

[0095] In this way, the diagnostic device 100 operates as a diagnostic device that executes an information provision method by reading and executing a program. The diagnostic device 100 can also realize the same functions as those of the above-described embodiment by reading the program from a recording medium using a media reader and executing the read program. Note that the program in these other embodiments is not limited to being executed by the diagnostic device 100. For example, the present invention can also be applied in the same way to cases where another computer or server executes the program, or where these execute the program in cooperation with each other.

[0096] This program can be distributed via a network such as the Internet. In addition, this program can be recorded on a computer-readable recording medium such as a hard disk, a flexible disk (FD), a CD-ROM, a magneto-optical disk (MO), or a digital versatile disk (DVD), and can be executed by being read from the recording medium by a computer.

[0097] (others) Some examples of combinations of the disclosed technical features are set out below.

[0098] (1) A network diagnostic system including a transmitting node, a receiving node, and a diagnostic device, wherein frames are transmitted from the transmitting node to the receiving node using multiple paths that are independent of each other, the transmitting node transmits a plurality of frames destined for the same receiving node via the plurality of routes, regardless of whether a failure has occurred in some of the plurality of routes; the receiving node measures the arrival times of the frames received from the same transmitting node based on a timer, and notifies the diagnostic device of the measurement results; The diagnostic device diagnoses the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction based on the measurement results. The diagnostic system that performs the action.

[0099] (2) The diagnostic system described in (1), wherein the diagnostic device selects some of the nodes included in the multiple routes and further executes a process of generating a pseudo-failure in the selected some of the nodes.

[0100] (3) A diagnostic system described in (1) or (2), in which the receiving node notifies the diagnostic device of the period during which some of the frames from the same transmitting node do not arrive after a pseudo-failure occurs on one of the multiple routes as the alternative route construction time.

[0101] (4) The diagnostic system according to (3), wherein the diagnostic device diagnoses the alternative path construction time as the time required to reconstruct the communication path of the network when the pseudo-failure occurs.

[0102] (5) A diagnostic system described in any one of (1) to (4), wherein, if the receiving node does not receive the frame from some of the multiple routes, the receiving node further executes a process of notifying the diagnostic device of information that the frame is not received from some of the routes.

[0103] (6) The diagnostic system described in (3), wherein the receiving node notifies the diagnostic device of the difference in arrival time of multiple frames received from the same transmitting node as the arrival time difference before a pseudo-fault occurs on one of the multiple routes, and notifies the diagnostic device of the difference in arrival time of multiple frames received from the same transmitting node as the time difference after fault setting after a pseudo-fault occurs on one of the multiple routes and route information has been reconstructed.

[0104] (7) The diagnostic device diagnoses the difference between the arrival time of a frame through the network before the reconfiguration and the arrival time of a frame through the network after the reconfiguration based on the arrival time difference before the fault setting and the time difference after the fault setting.

[0105] (8) a collection unit that collects measurement results of arrival times from a receiving node that receives a plurality of frames transmitted from the same transmitting node, regardless of whether a failure occurs in some of a plurality of independent paths included in the network; a diagnostic processing unit that diagnoses the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction based on the measurement results; A diagnostic device having:

[0106] (9) A method for diagnosing a network having a transmitting node, a receiving node, and a diagnostic device, in which frames are transmitted from the transmitting node to the receiving node using multiple paths that are independent of each other, comprising: the transmitting node transmits a plurality of frames destined for the same receiving node via the plurality of routes, regardless of whether a failure has occurred in some of the plurality of routes; the receiving node measures the arrival times of the frames received from the same transmitting node based on a timer, and notifies the diagnostic device of the measurement results; the diagnostic device diagnoses, based on the measurement results, the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction. A diagnostic method to perform the action. [Explanation of symbols]

[0107] 100 Diagnostic equipment 110 Communications Department 120 Input section 130 Display section 140 Storage section 141 First measurement result table 142 Second measurement result table 150 control section 151 Fault occurrence processing unit 152 Collection Department 153 Diagnostic processing unit

Claims

1. A network diagnostic system including a transmitting node, a receiving node, and a diagnostic device, wherein frames are transmitted from the transmitting node to the receiving node using multiple paths that are independent of each other, the transmitting node transmits a plurality of frames destined for the same receiving node via the plurality of routes, regardless of whether a failure has occurred in some of the plurality of routes; the receiving node measures the arrival times of the frames received from the same transmitting node based on a timer, and notifies the diagnostic device of the measurement results; The diagnostic device diagnoses the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction based on the measurement results. The diagnostic system that performs the action.

2. The diagnostic system according to claim 1 , wherein the diagnostic device further selects some nodes included in the plurality of routes and executes a process of generating a pseudo-failure in the selected some nodes.

3. The diagnostic system described in claim 2, wherein the receiving node notifies the diagnostic device of the period during which some of the frames from the same transmitting node do not arrive after a pseudo-failure occurs in one of the multiple routes as the alternative route construction time.

4. The diagnostic system according to claim 3 , wherein the diagnostic device diagnoses the alternative path construction time as a time required to reconstruct the communication path of the network when the pseudo-failure occurs.

5. The diagnostic system according to claim 1 or 2, wherein, when the receiving node does not receive the frame from some of the multiple routes, the receiving node further executes a process of notifying the diagnostic device of information that the frame is not received from some of the routes.

6. 4. The diagnostic system according to claim 3, wherein the receiving node notifies the diagnostic device of the difference in arrival times of multiple frames received from the same transmitting node as a pre-fault setting arrival time difference before a pseudo-fault occurs on one of the multiple routes, and notifies the diagnostic device of the difference in arrival times of multiple frames received from the same transmitting node as a post-fault setting time difference after a pseudo-fault occurs on one of the multiple routes and after route information has been reconstructed.

7. The diagnostic system of claim 7, wherein the diagnostic device diagnoses the difference between the arrival time of a frame through the network before the reconfiguration and the arrival time of a frame through the network after the reconfiguration based on the arrival time difference before the fault is configured and the time difference after the fault is configured.

8. a collection unit that collects measurement results of arrival times from a receiving node that receives a plurality of frames transmitted from the same transmitting node, regardless of whether a failure has occurred in some of a plurality of independent paths included in the network; a diagnostic processing unit that diagnoses the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction based on the measurement results; A diagnostic device having:

9. A diagnostic method for a network having a transmitting node, a receiving node, and a diagnostic device, wherein frames are transmitted from the transmitting node to the receiving node using multiple paths that are independent of each other, the method comprising: the transmitting node transmits a plurality of frames destined for the same receiving node via the plurality of routes, regardless of whether a failure has occurred in some of the plurality of routes; the receiving node measures the arrival times of the frames received from the same transmitting node based on a timer, and notifies the diagnostic device of the measurement results; the diagnostic device diagnoses, based on the measurement results, the time required to reconstruct the communication path of the network when the failure occurs and the performance of the network after the reconstruction. A diagnostic method to perform the action.

Images