Configuring a UDP Jitter Test Instance
Context
When configuring a UDP Jitter test instance, configure reachable routes between the UDP Jitter client and the UDP Jitter server.
You can set the number of packets to be sent consecutively in each test instance. This configuration is used to simulate certain traffic. For example, G.711 traffic can be simulated within 1 minute by sending 3000 UDP packets at an interval of 20 milliseconds.
NOTE: Configuring NTP on the client and the server can effectively improve the accuracy of the test.
The NQA client also functions as the UDP Jitter client. The jitter obtained in this test is the UDP Jitter. Perform the following steps on the NQA client.
The timeout, probe-count, frequency, jitter-packetnum, and interval commands constrain each other; therefore, properly set the values when running the five commands. Improper command settings may lead to test failure.
- On a network with poor quality and low transmission rate, increase the timeout value to ensure that the response to NQA detection packets can be received.
- On a network with low reliability, increase the probe-count value because multiple detection packets may need to be sent to ensure successful detection.
The frequency value must comply with the following rules:
frequency > interval × (probe-count × jitter-packetnum - 1) + timeout
Procedure
- Configure the UDP Jitter server.
- Configure the NQA client.
- (Optional) Run the following commands as required to configure parameters for the Jitter test:
Run description string
A description is configured for the test instance.
Run frequency interval
The test period is set for the NQA test instance.
Run timeout time
The timeout period of a probe is set for the NQA test instance.
Run source-address ipv4 ipv4-address
The source IP address is configured.
Run source-interface interface-type interface-number
The source interface used to send test packets is configured.
Run source-port port-number
The source port number is configured.
Run ttl number
The TTL value in the NQA test packet is set.
Run datasize size
The packet size is set for the NQA test instance.
Run datafill fillstring
The padding field is configured for the NQA test instance.
Run sendpacket passroute
The NQA test instance is configured to send packets without searching the routing table.
By default, the NQA test packets are sent with searching the routing table.
Run probe-count number
The number of probes in each test is set.
By default, the number of probes is 3.
Run tos value
Type of Service (TOS) is set for the test packet.
Run fail-percent percent
The failure percentage is set for the NQA test instance.
By default, the failure percentage is 100%, that is, the test is regarded failed only when all the probes fail.
Run interval { milliseconds interval | seconds interval }
The interval at which test packets are sent is set.
A shorter interval enables a test to be complete sooner. Delays occur during the sending and receiving of test packets on the processor. Therefore, if the interval for sending test packets is short, the Jitter test results are inaccurate.
Run jitter-packetnum number
The number of test packets sent in each probe is set.
By default, 20 packets are sent each time in each test.
The Jitter test is used to collect and analyze the delay variation during the UDP packet transmission. To improve the accuracy of the test result, the system sends multiple test packets each time. The more test packets are sent, the more accurate the statistics are, and the longer the test lasts.
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NOTE: The probe-count command sets the number of Jitter probes and the jitter-packetnum command sets the number of test packets sent during each probe. The product of probe count multiplied by the number of test packets must be less than or equal to 3000.
Run jitter-codec { g711a | g711u | g729a }
The code type is configured for jitter tests of analog voice services.
This command is applied only to jitter tests of analog voice services.
Run adv-factor factor-value
The advantage factor is configured for analog voice test calculation.
This command is applied only to jitter tests of analog voice services.
Run vpn-instance vpn-instance-name
The VPN instance name is configured.
Run records history number
The maximum number of historical records is set for the NQA test instance.
Run records result number
The maximum number of result records is set for the NQA test instance.
Run agetime hh:mm:ss
The aging time is set for the NQA test instance.
- (Optional) Run the following commands as required to configure parameters for the Jitter test:
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