Thursday 30 November 2017

Around sipp with pcap and authentication support

This is just a practical guide to have latest sipp on debian, to benefit from features that are not available in the stock package (sip-tester - version 3.2.1). For example support for playing pcap files or computing authentication hashes.

Build sipp with pcap support

apt-get install autoconf libncurses5-dev libpcap-dev g++
cd /usr/local/src/
git clone
cd sipp/
./ --with-pcap

./sipp is the built binary. You can see the version and capabilities with './sipp -v', e.g.:

$ ./sipp -v
SIPp v3.6-dev-149-gb95f98f-PCAP-RTPSTREAM.

This version will be able to use actions like

exec rtp_stream="file.wav"


exec play_pcap_audio="pcap/g711a.pcap"

(see details in current documentation).

A little caveat for 'rtp_stream' and WAV files. As the documentation says sipp expects a WAV file encoded with PCAM ('A-law'). You can also loop that audio for as long as you need, by adding ',-1' after the file name (and within the double quotes).
But sipp will also send the WAV header in the RTP payload. If this is not acceptable for you, then you can strip the WAV header with something like:

sox -t WAV -r 8000 -c 1 -e a-law audio.wav audio.raw

(where sox is this tool).

play_pcap_audio is useful when you want full control of the RTP produced by sipp, e.g. the exact RTP SSRC, missing packets, Mark set bits, etc. Very powerful.

Add authentication support

Same dependencies as above, but add:
apt-get install libssl-dev

./ --with-pcap --with-openssl

./sipp is the built binary. You can see the version and capabilities with './sipp -v', e.g.:

$ ./sipp -v
SIPp v3.6-dev-149-gb95f98f-TLS-PCAP-RTPSTREAM.

See the authentication features in current documentation.

More to come around these topics soon.

About ICE negotiation

Disclaimer: I wrote this article on March 2022 while working with Subspace, and the original link is here: