Latency Measurement - Viavi OneExpert DSL ONX-580 User Manual

Chapter 5 Data Testing
Running Speedtest
Press the Start button on the Speedtest screen. As the test progresses, its current state is
displayed. A green progress bar is presented when the state takes more than four seconds.
An activity spinner indicates that the test is still running.

Latency Measurement

The ONX will ping the Speedtest server the number of times specified in the Speedtest
configuration. The pings occur at whole millisecond intervals slightly greater than the
server connection phase's latency measurement. For example, if the server connection
phase's latency measurement for the server was 3.2 milliseconds, then the ping intervals
will occur at 4 milliseconds. An average ping delay value and a ping delay jitter value
(both in milliseconds) are provided for each ping. The final ping average result (in
milliseconds) is then derived.
Upload Measurement
The unit opens multiple connections to the Speedtest server. The upload transfer
begins, followed by updates of percentage complete and average upload rate (in bytes/
sec). Once the upload transfer has completed, the final upload rate measurement is then
provided.
Download Measurement
The unit opens multiple connections to the Speedtest server. The download transfer
then begins followed by updates of percentage complete and average download rate
(in bytes/sec). Once the download transfer has completed, the final download rate
measurement is provided.
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OneExpert DSL User's Guide
22052280, Rev. 015 April 2019