Does iperf support VOIP?

If yes! then please tell me what are the commands for testing voip and video streaming.

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6 Answers 6


I think you're confused about what Iperf is, and what purpose it serves.

From the Iperf Man Page:

iperf is a tool for performing network throughput measurements. It can test either TCP or UDP throughput. To perform an iperf test the user must establish both a server (to discard traffic) and a client (to generate traffic).

Iperf simply tests throughput by sending a stream TCP/UDP packets of a set size, over a set time, and then calculating the throughput.

Therefore, Iperf could certainly be utilized to simulate the underlying UDP flow of an RTP stream from a voice/video call. However, there would be nothing in the test that makes it any different from any other UDP flow or makes it VoIP specific.


iperf can be used to test transportation protocols like TCP and UDP. VOIP is an application protocol. This is another layer of the Internet Procol Suite.

So the answer is: no, you cannot test VOIP, but you can test the transportation protocols (typically UDP) used for VOIP calls.


Like user27884 said, you could configure Iperf server in this way:

iperf -s -u -p 5061 -S 0xC0 -l 200

..and the iperf client like this:

iperf -c -u -p 5061 -S 0xC0 -l 200 -t 200 -b 200k -i 10

this will show parcial results every 10 seconds and the entire test with 200 seconds.


To somewhat "emulate" a VoIP stream, set the -S to 0xC0 the udp payload (-l) to 200 bytes, the offered load (-b) to 200K, and with iperf 2+ set the protocol to UDP via -u on both the client and the server.


The program iperf is better used for testing data. The best tool to test VOIP is a program called sipp : http://sipp.sourceforge.net/.


If you are talking about measurement of QOS specific parameters (analyze VOIP protocols in depth), than no, iperf does not support those features. But you can use DSCP/TOS-field in packets (with iperf v3):

You can now set the DSCP/TOS bit vector using the -S <hexadecimal/decimal/octal number> client option. The option is exchanged with the server, so there is no need to set -S for the server. code.google.com

and jitter

PS the network devices are can have built-in QOS measurment, for example Cisco mediatrace

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