Configuring UDP jitter tests



Do not perform NQA UDP jitter tests on known ports, ports from 1 to 1023. Otherwise, UDP jitter tests might fail or the corresponding services of this port might be unavailable.

Real-time services such as voice and video have high requirements on delay jitters. UDP jitter tests of an NQA test group obtain uni/bi-directional delay jitters. The test results help you verify whether a network can carry real-time services.

A UDP jitter test performs the following procedure:

  1. The source sends packets to the destination port at regular intervals.

  2. The destination affixes a time stamp to each packet that it receives, and then sends the packet back to the source.

  3. Upon receiving the response, the source calculates the delay jitter, which reflects network performance. Delay refers to the amount of time it takes a packet to be transmitted from source to destination or from destination to source. Delay jitter is the delay variation over time.

Configuration prerequisites

UDP jitter tests require cooperation between the NQA server and the NQA client. Before you start UDP jitter tests, configure UDP listening services on the NQA server. For more information about UDP listening service configuration, see "."

To configure UDP jitter tests:




1. Enter system view.



2. Enter NQA test group view.

nqa entry admin-name operation-tag


3. Configure the test type as UDP jitter, and enter test type view.

type udp-jitter


4. Configure the destination address of UDP packets.

destination ip ip-address

By default, no destination IP address is configured.

The destination IP address must be the same as that of the listening service on the NQA server.

5. Configure the destination port of UDP packets.

destination port port-number

By default, no destination port number is configured.

The destination port must be the same as that of the listening service on the NQA server.

6. Specify the source port number of UDP packets.

source port port-number


By default, no source port number is specified.

7. Configure the size of the data field in each UDP packet.

data-size size


100 bytes by default.

8. Configure the string to be filled in the data field of each probe packet.

data-fill string


By default, the string is the hexadecimal number 00010203040506070809.

9. Configure the number of probe packets to be sent during each UDP jitter probe operation.

probe packet-number



10 by default.

10. Configure the interval for sending probe packets during each UDP jitter probe operation.

probe packet-interval packet-interval


20 milliseconds by default.

11. Configure the interval the NQA client must wait for a response from the server before it regards the response is timed out.

probe packet-timeout packet-timeout


3000 milliseconds by default.

12. Configure the source IP address for UDP jitter packets.

source ip ip-address


By default, no source IP address is specified.

The source IP address must be the IP address of a local interface. The local interface must be up. Otherwise, no probe packets can be sent out.

13. Configure optional parameters.

See ""


[NOTE: ]


The probe count command specifies the number of probe operations during one UDP jitter test. The probe packet-number command specifies the number of probe packets sent in each UDP jitter probe operation.