JP2017229003A - Network test system and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the test of one system or both systems, depending on whether each system is fixed in each test section, to enable fault localization on each test section basis without functional addition on the node side.SOLUTION: A network test system, which includes a plurality of node devices 10, 20, 30 connected in cascade through #0 system transmission line and #1 system transmission line, tests the normality of the #0 system transmission line and the #1 system transmission line for each test section, and also tests the normality of each device using an in-device monitoring function for each system. The network test system includes: device status verification means which sets a test section and verifies whether or not each system, #0 system and #1 system, is fixed in the set test section; and test means which, for each test section, repeats a loopback test of a section layer and in-device continuous monitoring on the basis of each test section, respectively for both #0 system and #1 system if the system is not fixed, and for selected one system if the system is fixed.SELECTED DRAWING: Figure 1

Description

  The present invention is a first-come-first-served uninterruptible switching system that realizes low delay as a main signal protection technique in a network. In a network that relays multiple nodes, it isolates faults for each section and quickly identifies fault locations. The present invention relates to a network test system and method.

  In the 1 + 1 uninterruptible switching system, the same frame copied to the transmission lines of the 0-system and the 1-system is transmitted from the transmission side node, and one frame is selected at the reception side node and transmitted to the subsequent stage. Usually, in the TDM service, in order to avoid delay fluctuation at the time of uninterruptible switching, the signal of the short delay transmission line that arrives first at the receiving node among the transmission lines of the 0 system and the 1 system, and arrives later Since the signal of the long delay transmission line is waiting, the system delay is fixed to the long delay transmission line.

  On the other hand, in the case of uninterrupted switching of Ethernet (registered trademark), the condition for delay change due to switching of the frame selection path is relaxed rather than TDM, so that frame waiting becomes unnecessary. In other words, the receiving node performs first-come-first-served uninterruptible switching in which a frame having a normal sequence number that arrives early is selected and transmitted. Usually, since the frame of the short delay transmission line arrives first, as long as the sequence number of the frame of the short delay transmission line continues, the delay can be reduced by preferentially transmitting the first received frame.

FIG. 5 shows a configuration example of an uninterruptible switching system (Patent Document 1).
In FIG. 5, one terminal node 10 and the other terminal node 20 are connected via a 0-system transmission line and a 1-system transmission line. The uninterruptible transmitters 11 and 21 of the terminal nodes 10 and 20 transmit the same frame, which is duplicated by assigning a sequence number to the input frame, to the 0-system transmission path and the 1-system transmission path. The uninterruptible receiving units 12 and 22 of the terminal nodes 10 and 20 detect the sequence number of the arriving frame and send the first frame for each sequence number.

FIG. 6 shows a configuration example of an uninterruptible switching system including a relay node.
In FIG. 6, one terminal node 10 and the other terminal node 20 are connected to a 0-system transmission line and a 1-system transmission line via a relay node 30. The uninterruptible transmitters 11 and 21 and the uninterruptible receivers 12 and 22 of the terminal nodes 10 and 20 have the same configuration as that shown in FIG. 5, and the uninterruptible switching control using the frame sequence number is performed. . The relay node 30 passes the frame sequence number without changing it.

  In this configuration, when performing fault isolation for each section, a loopback test (Non-Patent Document 1) in which an OAM frame is inserted and folded back in a target section is common. In the loopback test, it is necessary to assign a sequence number to the OAM frame, but an example in which the loopback test is performed in the 0-system transmission path and the 1-system transmission path will be described with reference to FIG. Here, the sequence number assigned to the OAM frame is “2”.

  From the uninterruptible transmission unit 11 of the terminal node 10, the user frames, OAM frames, and user frames of sequence numbers 1, 2, and 3 are transmitted in this order. The relay node 30 loops back the OAM frame with the sequence number 2 through the frame selection units 31 and 32 and the OAM function unit 33 and passes the user frame with the sequence numbers 1 and 3. In the uninterruptible receiving unit 22 of the terminal node 20, since the user frames with the sequence numbers 1 and 3 arrive, there is a problem that the missing sequence number 2 is erroneously detected as a packet loss. When a packet loss is detected in the first-priority first-time uninterruptible switching, an unnecessary delay occurs because the packet arrives on the long path side, but here either the 0-system transmission path or the 1-system transmission path Therefore, the OAM frame of sequence number 2 does not arrive and waits for timeout.

  In addition, since the uninterruptible transmission unit 21 of the terminal node 20 cannot determine that the OAM frame is transmitted between the terminal node 10 and the relay node 30, the user frames having the sequence numbers 1 and 2 are transmitted. Therefore, the sequence number 2 of the folded OAM frame from the relay node 30 to the terminal node 10 and the sequence number 2 of the user frame relayed by the relay node 30 overlap. In this case, the uninterrupted reception unit 12 of the terminal node 10 receives a sequence number error because it receives the same sequence number.

JP 2012-178665 A

ITU-T G.8113.1 / Y.1372.1

  In a first-come-first-served uninterruptible switching system, when fault isolation is performed using an OAM frame, there is a problem of sequence number skipping and sequence number duplication as described in FIG.

In the first-come-first-served uninterruptible switching system including a relay node, the following three points need to be considered.
(1) Checking the state in the node The first-priority uninterruptible switching system has a 0-system transmission line and a 1-system transmission line as shown in FIGS. Normally, if either transmission line is communicable, the path layer is judged to be communicable, but it is fixed in a state where the system is fixed to one system in preparation for work or the like. If the system becomes incapable of communication, even if a non-fixed system is communicable, communication as a path layer is impossible. System fixing is a function that prevents unintended switching during construction such as relocation of troubles and prevents long-term service interruption, and is common in a system having a redundant system. Therefore, as a system fixed system, it is indispensable to confirm the state in each node with respect to the fixed system.

(2) Understanding the effects of failure location and main signal Normally, an EQP (Equipment) alarm is defined as an alarm to notify that a node has failed. In this EQP alarm, each detection point is monitored inside the node, and a fault location in the node can be specified by detecting this alarm. However, since the EQP alarm does not distinguish between the parts required for ensuring the normality of the main signal in the path layer and the faults of parts not related to the main signal such as supervisory control, the simple EQP alarm cannot be used. There is a possibility that the result of determining that the path layer is normal is erroneously erroneously detected as abnormal.

(3) Rapid failure location identification To confirm the normality of the path layer, the key points are (1) confirmation of the state in the node and (2) understanding the influence of the main signal at the failure location. However, when the confirmation is made after grasping the details as described above, depending on the method, a high level skill is required for the carving worker, and the work time may be prolonged. When performing fault isolation for each section, it is necessary to specify the suspected part in a short time, and it is necessary to specify the faulty part quickly.

  The present invention provides a network test system and method for performing one- or two-system tests depending on whether or not a system is fixed in each test section, and enabling fault isolation for each test section without adding a function to the node side. The purpose is to do.

  In the first invention, a plurality of node devices are connected in cascade via the 0-system transmission line and the 1-system transmission line, and the normality of the 0-system transmission line and the 1-system transmission line for each test section, and the devices for each system In the network test system for testing the normality of the apparatus using the internal monitoring function, the apparatus status confirmation means for setting the test section and confirming whether the 0 system and the 1 system are fixed in the set test section, For each test section, section layer loops for each test section for both system 0 and system 1 when system is not fixed and for one system selected when system is fixed And a test means for repeating the back test and the constant monitoring in the apparatus.

  In the network test system according to the first aspect of the present invention, when the system is not fixed, the test means makes a normal determination if at least one test result for both the 0 system and the 1 system is normal in all test sections. In the fixed case, if the test result for one selected system is normal in all test sections, normal determination is performed, and if it is abnormal in at least one test section, abnormality determination is performed.

  In the network test system according to the first aspect of the present invention, the test means adopts a monitoring result of a point that affects the main signal of the path layer when performing constant monitoring within the apparatus.

  In the second invention, a plurality of node devices are connected in cascade via the 0-system transmission line and the 1-system transmission line, the normality of the 0-system transmission line and the 1-system transmission line for each test section, and the devices for each system In the network test method for testing the normality of the apparatus using the internal monitoring function, a first step of setting a test section and confirming whether or not the 0 system and the 1 system are fixed in the set test section; For each test section, section layer loops for each test section for both system 0 and system 1 when system is not fixed and for one system selected when system is fixed A second step of repeating the back test and the constant monitoring in the apparatus.

  In the network test method of the second invention, in the second step, when the system is not fixed, if at least one test result for both the 0 system and the 1 system is normal in all test sections, a normal determination is performed. In the case where the system is fixed, if the test result for one selected system is normal in all test sections, a normal determination is made, and if it is abnormal in at least one test section, an abnormality is determined.

  In the network test method of the second invention, the second step employs a monitoring result of a point that affects the main signal of the path layer when performing constant monitoring within the apparatus.

  The present invention can autonomously communicate as a system test result by setting the test section and acquiring the results of section layer loopback test and continuous monitoring in the device depending on whether the system is fixed or not. Alternatively, it can be determined that communication is impossible.

It is a figure which shows the structural example of the network test system of this invention. It is a flowchart which shows the example of a process sequence of the network test system of this invention. It is a figure which shows the example of a determination of the continuous monitoring in the apparatus of the network test system (no system fixation) of this invention. It is a figure which shows the example of a determination of the continuous monitoring in a network test system (with system fixation) of this invention. It is a figure which shows the structural example of an uninterruptible switching system. It is a figure which shows the structural example of the uninterruptible switching system containing a relay node. It is a figure which shows the structural example of the conventional network test system.

FIG. 1 shows a configuration example of a network test system of the present invention.
In FIG. 1, one terminal node 10 and the other terminal node 20 are connected to a 0-system transmission line and a 1-system transmission line via a relay node 30. The terminal node 10 includes an uninterruptible transmission unit 11, an uninterruptible reception unit 12, an OAM function unit 13, a 0-system interface unit (IF # 0) 14, and a 1-system interface unit (IF # 1) having functions similar to those of the prior art. ) 15. The terminal node 20 includes an uninterruptible transmission unit 21, an uninterruptible reception unit 22, an OAM function unit 23, a 0-system interface unit (IF # 0) 24, and a 1-system interface unit (IF # 1) having functions similar to those of the conventional node. ) 25. The relay node 30 includes an OAM function unit 33, a 0-system interface unit (IF # 0) 34-1 and 34-2, and a 1-system interface unit (IF # 1) 35-1 and 35-2 having functions similar to those of the conventional one. In place of the frame selection units 31 and 32, section loopback (LB) units 36 and 37 corresponding to the 0-system and the 1-system are provided.

  A feature of the present invention resides in that the loopback test of the section layer and the constant monitoring in the apparatus are combined for the 0-system transmission line and the 1-system transmission line instead of the conventional path layer. Therefore, the OAM function unit 13 of the termination node 10, the OAM function unit 23 of the termination node 20, and the OAM function unit 33 of the relay node 30 separate the tests for the 0-system transmission path and the 1-system transmission path, respectively, and The back signal and the constant monitoring in the apparatus are performed. The section loopback (LB) units 36 and 37 of the relay node 30 are configured to loop back the OAM frame at the section layer instead of the path layer.

  In each OAM function unit 13, 23, 33, the loopback test of the section layer and the constant monitoring in the apparatus are performed separately for the 0 system and the 1 system for each test section under the control of the upper test control apparatus 40, or Perform for both 0 and 1 systems.

FIG. 2 shows a processing procedure example of the network test system of the present invention.
In FIG. 2, a test section is set, normality confirmation processing is entered for each set test section (S1), and the apparatus state is checked for each test section to determine whether the system is fixed or not (S2). If the system is not fixed, a section layer loopback test is performed on the 0-system transmission line and the 1-system transmission line to check the normality (S3). Here, when it is determined that the test result of either one of the systems is normal, the system 0 is constantly monitored for the 0 system and the 1 system, and the normality is confirmed (S4). On the other hand, if the system is fixed in the determination in step S2, a section layer loopback test is performed on the selected system, and normality is confirmed (S5). Here, when it is determined that the test result of the selected system is normal, the selected system is constantly monitored in the apparatus and the normality is confirmed (S6). When the test result of one of the systems is determined to be normal in step S4, or the test result of the selected system is determined to be normal in step S6, the normal check result of the set test section is stored. (S7), and the processing of steps S1 to S6 is repeated until there is no unexecuted test section (S8). When normal test results are obtained in all test sections, the system test results are recorded as being communicable (S9).

  On the other hand, if the result of the loopback test in step S3 or the constant monitoring in the apparatus in step S4 for system 0 and system 1 shows an abnormality in the set test section, the system test result cannot be communicated regardless of other test sections. (S9). Similarly, if the result of the loopback test in step S5 or the continuous monitoring in the apparatus in step S6 with respect to the selected system of system 0 or system 1 shows an abnormality in the set test section, the system is irrespective of other test sections. The test result is recorded as communication impossible (S9).

FIG. 3 shows an example of determination of continuous monitoring within the apparatus of the network test system (no system fixing) of the present invention.
In FIG. 3, the terminal nodes 10 and 20 and the relay node 30 perform continuous monitoring in the apparatus for each of the 0-system and the 1-system, dividing the points in the path layer that are affected / not affected, and the results are normal: ○, Abnormal: Indicated by ×.

  Without system fixing, system 0 and system 1 have redundant configurations, so even if one system fails, it is determined that communication is possible as the path layer. Here, the monitoring result of the point that does not affect the main signal of the path layer is ignored, and determination is made if at least one of the monitoring results is normal: ◯ at the point that affects the main signal of the path layer in the 0 system or 1 system. The result is normal: ○.

FIG. 4 shows a determination example of continuous monitoring in the apparatus of the network test system (with system fixing) of the present invention.
In FIG. 4, the selected transmission lines of the 0 system and the 1 system are indicated by solid lines, and are indicated by broken lines of non-selected transmission lines. If the point that has an influence on the main signal is normal in the selected system, the path layer is determined to be communicable even if a failure has occurred in the non-selected system section. As shown in Figs. 4 (1) and (2), even if the system that is determined to be abnormal by the constant monitoring in the device is the same, whether the system is a selected system or a non-selected system may further affect the main signal of the path layer. Judgment results differ depending on whether there is any effect.

10, 20 Termination node 11, 21 Uninterruptible transmission unit 12, 22 Uninterruptible reception unit 13, 23 OAM function unit 14, 240 System interface unit (IF # 0)
15, 25 1 system interface part (IF # 1)
30 Relay node 31, 32 Frame selection unit 33 OAM function unit 34 0 system interface unit (IF # 0)
35 1 system interface part (IF # 1)
36, 37 section loopback (LB) section

Claims (6)

A plurality of node devices are connected in cascade via the 0-system transmission line and the 1-system transmission line, and the normality of the 0-system transmission line and the 1-system transmission line for each test section and the function of constant monitoring in the equipment for each system are provided. In a network test system that uses equipment to test the normality of the device,
A device state confirmation means for setting the test section and confirming whether the system 0 and system 1 are fixed in the set test section;
For each of the test sections, the section layer of each of the test sections for each of the 0 system and the 1 system when the system is not fixed, and for one system selected when the system is fixed, respectively. A network test system comprising: a loopback test and a test means for repeating the constant monitoring in the apparatus. The network test system according to claim 1,
The test means performs a normal determination if at least one test result for both the 0 system and the 1 system is normal in all test sections when the system is not fixed, and is selected when the system is fixed. A network test system characterized in that, if the test result for one of the systems is normal in all test sections, it is judged as normal, and if it is abnormal in at least one test section, it is judged as abnormal. The network test system according to claim 1,
The network testing system, wherein the test means adopts a monitoring result of a point having an influence on a main signal of a path layer when the in-device continuous monitoring is performed. A plurality of node devices are connected in cascade via the 0-system transmission line and the 1-system transmission line, and the normality of the 0-system transmission line and the 1-system transmission line for each test section and the function of constant monitoring in the equipment for each system are provided. In a network test method for testing the normality of a device using:
A first step of setting the test interval and confirming whether or not system 0 and system 1 are fixed in the set test interval;
For each of the test sections, the section layer of each of the test sections for each of the 0 system and the 1 system when the system is not fixed, and for one system selected when the system is fixed, respectively. A network test method comprising: a loopback test and a second step of repeating the constant monitoring in the apparatus. The network test method according to claim 4, wherein
In the second step, when the system is not fixed, a normal determination is made if at least one test result for both the 0 system and the 1 system is normal in all test sections, and when the system is fixed. A network test method characterized in that if a test result for one selected system is normal in all test sections, a normal determination is made, and if an abnormality is found in at least one test section, an abnormality is determined. The network test method according to claim 4, wherein
The network testing method according to claim 2, wherein the second step employs a monitoring result of a point that affects the main signal of the path layer when the in-device continuous monitoring is performed.

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