JP2022148132A - Network measurement apparatus and frame loss measuring method therefor - Google Patents

Abstract

To provide a network measurement apparatus that even when abnormality occurs at a measurement object, is capable of early making it possible to normally measure a frame loss.SOLUTION: A network measurement apparatus comprises: a data generation unit 2 comprising Frame generation units 21a, 21b, 21c, and 21d for generating measurement frames, SN addition units 22a, 22b, 22c, and 22d for setting consecutive serial numbers to the measurement frames, and a data transmission unit 25 for transmitting the measurement frames to a measurement object; and a measurement unit 3 comprising a data reception unit 31 for receiving the measurement frames from the measurement object, HighestSN/OldSN detection units 34a, 34b, 34c, and 34d that for each measurement section of a predetermined time, output the maximum value of serial numbers of measurement frames received in the measurement section as a HighestSN, and a FrameLoss calculation unit 35 for calculating the number of frame losses in a target measurement section from a HighestSN in the target measurement section, a HighestSN in the immediately previous measurement section, and the number of received frames.SELECTED DRAWING: Figure 1

Description

The present invention relates to a network measuring device for measuring the performance of a network or a transmission device that constitutes the network.

2. Description of the Related Art There is a network measurement device that measures the performance of a network or a transmission device that constitutes the network by transmitting and receiving a measurement frame to the network or the transmission device that constitutes the network.

Patent Document 1 describes counting the number of transmissions and receptions of measurement frames to measure frame loss.

There is also a device that sets a serial number in a measurement frame and measures frame loss based on the serial number of the received measurement frame.

In this way, in the method of setting the serial number in the measurement frame, there is a limit to the length of the serial number that can be set in the measurement frame. If overflow occurs, the frame loss measurement will not be accurate.

In order to deal with this overflow, some devices monitor the upper and lower bits of the serial number to detect the occurrence of overflow.

JP 2014-023032 A

In such a measurement device, if the measurement frame is lost due to a failure of the network equipment to be measured near the overflow, the overflow cannot be detected and the frame loss can be measured normally. It took me a long time to be able to do

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a network measurement apparatus capable of measuring frame loss normally even when an abnormality occurs in a measurement target.

A network measurement device according to the present invention includes a frame generation unit that generates a measurement frame, a serial number addition unit that sets a continuous serial number in the measurement frame, and a data transmission unit that transmits the measurement frame to a measurement target. a data generator that receives the measurement frame from the measurement target; and a serial number detector that outputs the maximum value of the serial numbers of the measurement frames received during each measurement interval of a predetermined time as HighestSN. and a frame loss calculator that calculates the number of frame losses in the target measurement interval from the HighestSN of the target measurement interval, the HighestSN of the immediately preceding measurement interval, and the number of received frames. It is.

With this configuration, the number of frame losses in the target measurement section is calculated from the Highest SN of the target measurement section, the Highest SN of the immediately preceding measurement section, and the number of received frames. Therefore, even if the measurement frame is lost due to a failure of the device to be measured, the correct HighestSN can be obtained early after the measurement data is restored, and the frame loss measurement can be performed normally. can.

Further, in the network measurement device of the present invention, the serial number detection unit outputs, as OldSN, the number of measurement frames in which a serial number smaller than the HighestSN of the immediately preceding measurement interval is set, and the frame loss calculation unit The number of frame losses in the target measurement interval is calculated from the HighestSN of the target measurement interval, the HighestSN of the immediately preceding measurement interval, the OldSN of the target measurement interval, the OldSN of the immediately following measurement interval, and the number of received frames.

With this configuration, the number of frame losses in the target measurement section is calculated from the HighestSN of the target measurement section, the HighestSN of the immediately preceding measurement section, the OldSN of the target measurement section, the OldSN of the immediately following measurement section, and the number of received frames. be. Therefore, even if there is a possibility that the serial numbers will be received out of order, if the measurement frame is lost due to a failure of the device being measured, etc., the correct HighestSN can be obtained as soon as the measurement data is restored. , the frame loss measurement can be performed normally.

Further, in the network measurement device of the present invention, the frame loss calculation unit uses a value obtained by subtracting the HighestSN of the immediately preceding measurement interval and the OldSN of the immediately following measurement interval from the HighestSN of the target measurement interval as the frame number expected value, A value obtained by subtracting the OldSN of the target measurement section from the number of received frames in the target measurement section is defined as the corrected number of received frames, and a value obtained by subtracting the corrected number of received frames from the expected number of frames is defined as the number of frame losses.

With this configuration, the value obtained by subtracting the Highest SN of the immediately preceding measurement interval and the Old SN of the immediately following measurement interval from the Highest SN of the target measurement interval is used as the expected number of frames. The value obtained by subtracting the OldSN is the corrected received frame number, and the frame loss number is obtained by subtracting the corrected received frame number from the frame number expected value. Therefore, even if there is a possibility that the serial numbers will be received out of order, if the measurement frame is lost due to a failure of the device being measured, etc., the correct HighestSN can be obtained as soon as the measurement data is restored. , the frame loss measurement can be performed normally.

Further, in the network measurement device of the present invention, the data generation unit includes a plurality of sequences each composed of the frame generation unit and the serial number addition unit, and includes identification information for identifying the sequence in the measurement frame of each sequence. and a data multiplexer for multiplexing the measurement frames of the sequence and outputting them to the data transmission unit, wherein the measurement unit divides the measurement frames received by the data reception unit into a plurality of measurement frames. a data demultiplexer for distribution, an identification information identification unit for distributing the measurement frame from the identification information of the measurement frame distributed by the data demultiplexer to the plurality of serial number detection units provided for each series; and the frame loss calculation unit sets the sum of the expected values of the number of frames of the plurality of sequences as the expected value of the total number of frames, and calculates the OldSN of the plurality of sequences from the number of all the measurement frames received in the target measurement interval is used as the number of corrected received frames, and the number obtained by subtracting the number of corrected received frames from the expected value of the total number of frames is used as the frame loss number.

With this configuration, multiple sequences of measurement frames are multiplexed and transmitted, the received measurement frames are distributed to the multiple sequences, and the sum of the expected values of the number of frames of the multiple sequences is the expected value of the total number of frames, The number obtained by subtracting the OldSN of multiple sequences from the number of all measurement frames received in the target measurement interval is the total number of corrected received frames, and the number obtained by subtracting the total number of corrected received frames from the expected value of the total number of frames is the number of frame losses. It is said that Therefore, even if the measurement frames of multiple sequences are multiplexed to speed up the process, if the measurement frames are lost due to a failure of the equipment to be measured, the correct HighestSN can be obtained as soon as the measurement data is restored. It is possible to enable frame loss measurement to be performed normally.

Further, in the frame loss measurement method of the present invention, a continuous serial number is set in a measurement frame and transmitted to the measurement target, and based on the serial number of the measurement frame received from the measurement target for each measurement interval of a predetermined time A frame loss measurement method for a network measurement device for calculating the number of frame losses, comprising the steps of: setting the maximum value of the serial numbers of the measurement frames received within the measurement interval to HighestSN; and calculating the number of frame losses in the target measurement section from the HighestSN of the measurement section and the number of received frames.

With this configuration, the number of frame losses in the target measurement section is calculated from the Highest SN of the target measurement section, the Highest SN of the immediately preceding measurement section, and the number of received frames. Therefore, even if the measurement frame is lost due to a failure of the device to be measured, the correct HighestSN can be obtained early after the measurement data is restored, and the frame loss measurement can be performed normally. can.

INDUSTRIAL APPLICABILITY The present invention can provide a network measurement apparatus capable of measuring frame loss normally even at an early stage even if an abnormality occurs in the measurement target.

FIG. 1 is a block diagram of a network measurement device according to one embodiment of the present invention. FIG. 2 is a diagram showing a method of calculating the number of frame losses of the network measuring device according to one embodiment of the present invention. FIG. 3 is a diagram showing a configuration example of the serial number and carry flag of the network measuring device according to one embodiment of the present invention. FIG. 4 is a diagram showing an overflow corresponding section of the serial number of the network measuring device according to the embodiment of the present invention. FIG. 5 is a time chart showing an example of loss of a measurement frame of the network measurement device according to one embodiment of the present invention. FIG. 6 is a diagram showing an example of serial numbers when a measurement frame is lost in the network measurement device according to one embodiment of the present invention.

Hereinafter, network measurement devices according to embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 1, a network measurement device 1 according to an embodiment of the present invention includes a data generation section 2 and a measurement section 3. FIG.

The data generation unit 2 generates a measurement frame to be transmitted to a network to be measured or a transmission device constituting the network.

The data generation unit 2 includes frame generation units 21a, 21b, 21c, and 21d as frame generation units, SN addition units 22a, 22b, 22c, and 22d as serial number addition units, and laneID addition units as identification information addition units. 23a, 23b, 23c, 23d, a data multiplexer 24, and a data transmission unit 25.

The frame generators 21a, 21b, 21c, and 21d generate measurement frames according to the communication standard supported by the measurement target.

The SN adding units 22a, 22b, 22c, and 22d set consecutive serial numbers to the measurement frames generated by the frame generating units 21a, 21b, 21c, and 21d, respectively. For example, the SN addition units 22a, 22b, 22c, and 22d set the serial number by starting from zero and adding 1 for each generated measurement frame. Set to zero.

The laneID adding units 23a, 23b, 23c, and 23d set, in the measurement frame, laneIDs that identify the frame generation units 21a, 21b, 21c, and 21d that generated the measurement frame.

The data multiplexer 24 multiplexes and outputs the measurement frames output from the laneID adding units 23a, 23b, 23c, and 23d.

The data transmission section 25 transmits the measurement frame multiplexed by the data multiplexer 24 to the measurement object.

In the data generator 2, each frame generator 21a, 21b, 21c, 21d generates a measurement frame at a speed of, for example, 100 Gbps, multiplexes them in a data multiplexer 24, and transmits them to the measurement target at a speed of 400 Gbps. It's like

The measurement unit 3 extracts a measurement frame from the data received from the measurement target, and measures frame loss based on the serial number set in the measurement frame.

The measurement unit 3 includes a data reception unit 31, a data demultiplexer 32, a laneID identification unit 33 as an identification information identification unit, HighestSN/OldSN detection units 34a, 34b, 34c, and 34d as serial number detection units, and a frame and a FrameLoss calculator 35 as a loss calculator.

The data receiving section 31 receives data from the object to be measured, extracts a measurement frame from the received data, and outputs it to the data demultiplexer 32 .

The data demultiplexer 32 distributes and outputs the received measurement frame. In this embodiment, data demultiplexer 32 divides the received measurement frame into four.

The laneID identification unit 33 distributes the distributed measurement frame to four according to the laneID set in the measurement frame and outputs them.

The HighestSN/OldSN detection units 34a, 34b, 34c, and 34d calculate the expected value of the number of received frames and the like by a method described later based on the serial number set in the measurement frame.

The FrameLoss calculation unit 35 calculates the number of frame losses using a method described later based on the expected number of received frames calculated by the HighestSN/OldSN detection units 34a, 34b, 34c, and 34d.

In this embodiment, the measurement unit 3 uses a predetermined measurement time as a measurement interval and calculates the number of frame losses in the measurement interval based on the serial numbers of the measurement frames received during the measurement interval. It is desirable that the measurement period should be a period during which at least about 10 frames can be received. If the measurement frame is 64 bytes long and the bit rate is 400 Gbps, it will take about 1.5 ms. There is no upper limit for the measurement interval, but the longer the measurement interval, the longer it takes for the frame loss results to be determined, so in reality, the upper limit is about 60s.

The HighestSN/OldSN detectors 34a, 34b, 34c, and 34d set the maximum value of the serial numbers of the measurement frames received within the measurement interval as HighestSN.

In this embodiment, due to the configuration using multiplexers and demultiplexers, the serial numbers received may be out of order. For this reason, the measurement frames received with a delay exceeding the measurement interval are counted to ensure consistency. The HighestSN/OldSN detectors 34a, 34b, 34c, and 34d set OldSN as the number of measurement frames in which a serial number smaller than the HighestSN of the immediately preceding measurement interval is set.

The HighestSN/OldSN detectors 34a, 34b, 34c, and 34d calculate an expected value of the number of received frames in the middle measurement interval from the HighestSN and OldSN of the three measurement intervals.

For example, in the case shown in FIG. 2, the expected number of frames in section 2 is calculated by the following formula.
Highest SN#2 - Highest SN#1 - Old SN#3
= 14 - 7 - 1 = 6
here,
HighestSN#2 : HighestSN of section 2
HighestSN#1 : HighestSN of section 1
OldSN#3 : OldSN of section 3

The number of actually measured frames received in interval 2 is 7 with serial numbers of 6, 8, 9, 10, 11, 12, and 14, and the number obtained by subtracting the OldSN of interval 2 from the number of actually measured frames is the corrected number of received frames. . In this case, the number of modified received frames is 7 - 1 = 6 frames.

The number of frame losses is the expected number of frames minus the corrected number of received frames. In this case, the frame loss number is 6 - 6 = 0 and no frame loss.

Here, if the frame with serial number 10 is lost, the number of actually measured frames is 6, the number of corrected received frames is 5, and the number of frame losses is calculated as 1.

The HighestSN/OldSN detectors 34a, 34b, 34c, and 34d calculate the expected value of the number of frames in each measurement interval and output it to the FrameLoss calculator 35 together with OldSN.

The FrameLoss calculator 35 sets the sum of the four expected values for the number of frames as the expected value for the total number of frames. The FrameLoss calculation unit 35 determines the number obtained by subtracting 4 OldSNs from the number of all measurement frames received in the measurement interval as the number of all corrected received frames. The FrameLoss calculator 35 determines the number of frame losses by subtracting the number of all corrected received frames from the expected value of all frames.

In this embodiment, the serial number is set to 8 bits. Since the serial number is a finite numerical value due to the number of bits, countermeasures against overflow are required for practical use in measurement. Also, as mentioned above, due to the configuration using multiplexers and demultiplexers, the serial numbers received may be out of order. Therefore, the HighestSN/OldSN detectors 34a, 34b, 34c, and 34d manage carry flags based on the received serial numbers, as shown in FIG. When the carry flag is 1, an overflow has occurred.

As mentioned above, the received serial numbers may be out of order, not consecutive. Yes, and the upper 2 bits of the serial number of the newly received measurement frame are '00'.

For example, when the serial number is 8 bits, as shown in FIG. 4, the section between 192 and 63 of the serial number is the section corresponding to the overflow.

HighestSN/OldSN detection units 34a, 34b, 34c, and 34d detect OldSN in consideration of overflow when overflow occurs in the immediately preceding measurement interval and the serial number after overflow from zero becomes HighestSN. calculate. Specifically, OldSN is the sum of the number of measurement frames with a serial number before overflow and the number of measurement frames with a serial number smaller than HighestSN in the immediately preceding measurement interval among the serial numbers after overflow from zero. do.

Here, consider a case where measurement frames are lost during measurement due to a failure of a network device to be measured or the like.

For example, if the maximum serial number received from the start of measurement is set to HighestSN, and if an overflow occurs, the maximum serial number received from that point is set to HighestSN. can calculate the number of frame losses.

However, as shown in FIG. 5, the transmission data of the measurement frame is lost due to a failure of the network equipment when the serial number within the overflow-supported section is 200, and the serial number outside the overflow-supported section is 65. , the HighestSN is erroneously recognized as 200 because 65 is smaller than 200.

After that, as shown in FIG. 6, the HighestSN is fixed at 200, and the number of frame losses cannot be calculated normally until the serial number exceeds 200.

In this embodiment, the maximum value of the serial numbers of the measurement frames received within the measurement interval is HighestSN. Therefore, in FIG. The number of frame losses can be calculated normally from the second measurement interval.

As described above, in the above-described embodiment, the HighestSN/OldSN detection units 34a, 34b, 34c, and 34d set the maximum value of the serial numbers of the measurement frames received in each measurement interval to HighestSN, and the FrameLoss calculation unit 35 calculates the number of frame losses in the target measurement interval from the Highest SN of the target measurement interval, the Highest SN of the immediately preceding measurement interval, and the number of received frames.

As a result, even if the measurement frame is lost due to a failure of the device being measured, the correct HighestSN can be obtained as soon as the measurement data is restored, and the frame loss measurement can be performed normally. can.

The HighestSN/OldSN detection units 34a, 34b, 34c, and 34d set OldSN as the number of measurement frames in which a serial number smaller than the HighestSN of the immediately preceding measurement interval is set. The number of frame losses in the target measurement interval is calculated from the HighestSN of the immediately preceding measurement interval, the OldSN of the target measurement interval, the OldSN of the immediately following measurement interval, and the number of received frames.

As a result, even if there is a possibility that the order in which the serial numbers are received may be out of order, the correct HighestSN can be obtained as soon as the measurement data is restored even if the measurement frame is lost due to a failure of the device being measured. , the frame loss measurement can be performed normally.

The FrameLoss calculation unit 35 subtracts the Highest SN of the immediately preceding measurement interval and the Old SN of the immediately following measurement interval from the Highest SN of the target measurement interval as the expected number of frames. The value obtained by subtracting OldSN in the measurement period is defined as the corrected number of received frames, and the value obtained by subtracting the corrected number of received frames from the expected number of frames is defined as the number of frame losses.

As a result, even if there is a possibility that the order in which the serial numbers are received may be out of order, the correct HighestSN can be obtained as soon as the measurement data is restored even if the measurement frame is lost due to a failure of the device being measured. , the frame loss measurement can be performed normally.

In addition, the data generation unit 2 generates measurement frames with a plurality of sequences, adds consecutive serial numbers to the respective sequences, multiplexes the measurement frames of the plurality of sequences, and transmits the measurement frames to the measurement object, and the measurement unit 3 , the measurement frame received from the measurement target is restored to a plurality of sequences, the HighestSN and OldSN are obtained by the HighestSN/OldSN detection units 34a, 34b, 34c, and 34d for each sequence, and the FrameLoss calculation unit 35 calculates the frames of the plurality of sequences. The total number of expected values is defined as the expected value for the total number of frames. The frame loss number is obtained by subtracting the corrected received frame number.

As a result, even if multiple series of measurement frames are multiplexed and speeded up, if the measurement frames are lost due to a failure of the device being measured, etc., the correct HighestSN can be obtained quickly after the measurement data is restored. It is possible to enable frame loss measurement to be performed normally.

Note that the network measurement device 1 of the present embodiment can be connected to the network to be measured by itself, and can perform measurement by receiving the measurement frame transmitted by the device itself. and a receiving device can be connected to the networks to be measured, respectively, and measurement can be performed by transmitting a measurement frame from the transmitting device to the receiving device.

Although embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

1 network measurement device 2 data generation unit 3 measurement unit 21a, 21b, 21c, 21d frame generation unit (frame generation unit)
22a, 22b, 22c, 22d SN addition section (serial number addition section)
23a, 23b, 23c, 23d laneID addition unit (identification information addition unit)
24 data multiplexer 25 data transmission unit 31 data reception unit 32 data demultiplexer 33 laneID identification unit (identification information identification unit)
34a, 34b, 34c, 34d HighestSN/OldSN detector (serial number detector)
35 FrameLoss calculator (frame loss calculator)

Claims (5)

frame generation units (21a, 21b, 21c, 21d) for generating measurement frames; serial number addition units (22a, 22b, 22c, 22d) for setting consecutive serial numbers to the measurement frames; a data generator (2) comprising a data transmitter (25) for transmitting to a target;
A data receiving unit (31) that receives the measurement frame from the measurement object, and a serial number detection unit (34a , 34b, 34c, 34d), the HighestSN of the target measurement interval, the HighestSN of the immediately preceding measurement interval, and the number of received frames, a frame loss calculator (35) for calculating the number of frame losses in the target measurement interval a network measuring device comprising a measuring unit (3) comprising: The serial number detection unit outputs, as OldSN, the number of measurement frames for which a serial number smaller than the HighestSN of the immediately preceding measurement interval is set, and the frame loss calculation unit detects the HighestSN of the target measurement interval and 2. The network measuring device according to claim 1, wherein the number of frame losses in the target measurement section is calculated from the HighestSN of the section, the OldSN of the target measurement section, the OldSN of the immediately following measurement section, and the number of received frames. The frame loss calculation unit uses a value obtained by subtracting the HighestSN of the immediately preceding measurement interval and the OldSN of the immediately following measurement interval from the HighestSN of the target measurement interval as an expected number of frames, and calculates the number of received frames in the target measurement interval as the target measurement 3. The network measuring device according to claim 2, wherein a value obtained by subtracting the OldSN of the section is used as the corrected number of received frames, and a value obtained by subtracting the corrected number of received frames from the expected value of the number of frames is used as the number of frame losses. The data generation unit comprises a plurality of sequences composed of the frame generation unit and the serial number addition unit, and identification information addition units (23a, 23b) for adding identification information for identifying the sequence to the measurement frame of each of the sequences. , 23c, 23d), and a data multiplexer (24) that multiplexes the measurement frames of the series and outputs them to the data transmission unit,
The measurement unit includes a data demultiplexer (32) for distributing the measurement frame received by the data reception unit into a plurality of units, and the identification information of the measurement frame distributed by the data demultiplexer for each sequence. and an identification information identification unit (33) for distributing the measurement frame to the plurality of serial number detection units, wherein the frame loss calculation unit calculates the sum of the expected values of the number of frames of the plurality of sequences as the total number of frames. an expected value, a number obtained by subtracting the OldSN of the plurality of sequences from the number of all the measurement frames received in the target measurement interval, and the total number of corrected received frames is calculated from the expected value of the total number of frames 4. The network measuring device according to claim 3, wherein the subtracted number is the number of frame losses. A network measuring device (1) for setting a continuous serial number in a measurement frame, transmitting it to a measurement target, and calculating the number of frame losses based on the serial number of the measurement frame received from the measurement target for each measurement interval of a predetermined time ) frame loss measurement method,
setting the maximum value of the serial numbers of the measurement frames received within the measurement interval to HighestSN;
A frame loss measurement method comprising: calculating the number of frame losses in the target measurement section from the HighestSN of the target measurement section, the HighestSN of the immediately preceding measurement section, and the number of received frames.

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