Sniff and record VoIP calls with VoIPong

by Bruce Stewart

voipong_20070528.jpgOver on, Jason Striegel points us to VoIPong, a VoIP network sniffer that allows you to capture and record any VoIP call that crosses your network.

From the VoIPong home page:

VoIPong is a utility which detects all Voice Over IP calls on a pipeline, and for those which are G711 encoded, dumps actual conversation to seperate wave files. It supports SIP, H323, Cisco's Skinny Client Protocol, RTP and RTCP.

There's a server daemon that sets your network adapter to promiscuous mode and watches for VoIP calls. Calls are automatically logged and the G.711 encoded conversations will be named by date and dumped in wav format to an output directory (sox is required to make this work). There's also a handy monitoring tool that will allow you to see what conversations are currently being monitored.

I tried it out this evening and it really works, recording both ends of the conversation to a WAV file. This could be a really handy tool for recording podcasts from a VoIP client that doesn't have a recording feature (Netmeeting, for example). You'll probably need to tweak mic levels on both ends, or one end of the conversation will sound louder than the other.

Jason also provides some OS X-specific installation instructions over on his Hackzine post.


Jason Sjöbeck
2007-06-03 20:23:54
There is another angle on this, namely that those of us who deploy VoIP in our clients organizations need to think about using VLAN's, VPN's, and even the emerging SSL for RTSP standards, in order to protect privacy.
2007-07-20 04:00:34
I highly recommend you to try another VOIP recording application:Duxoft MiaRec (

MiaRec is a software application for recording and monitoring calls in any of Voip protocols (H.323, SIP, MGCP, Cisco SCCP).

It records calls directly from network without loss in voice quality.

You can easily replay your conversation with it in MP3 or WAV format.
MiaRec can be used for recording many simultaneous calls as well as only one call at the time.

2008-07-01 11:12:03
hey jason...
i just wanna to ask u something...
i cant do ./configure but i pass that
i do the make and just as you said i error ok, the i did the
# cc -fPIC -g -Wall -Iinclude -c modvocoder_pcma.c
# libtool -lc -dynamic -o modvocoder_pcma.o
# cc -fPIC -g -Wall -Iinclude -c modvocoder_pcmu.c
# libtool -lc -dynamic -o modvocoder_pcmu.o

all ok but then
i try again the make command and is keep saying 1 error..... what sould i do?? pls replay
with love Zap