You can try VoIPong with Microsoft Netmeeting. Set up netmeeting so that it uses G711 at both ends, and make a voice call. You'll see the calls captured and wave files created after your call finishes.
If you do not have a testbed, do not want so much pain to test VoIPong, you can replay a test capture file in your machine and see if it is catched.
Download this test call capture, where me and Baris are talking about EnderUNIX team.
Download and install tcpreplay tool. Tcpreplay tool reads pcap capture files, and re-injects the packets into a live network.
Start VoIPong
04/12/05 16:27:20: EnderUNIX VOIPONG Voice Over IP Sniffer starting... 04/12/05 16:27:20: Release 2.0-DEVEL running on efe.enderunix.org [FreeBSD 5.4-STABLE FreeBSD 5.4-STABLE #0: Sun Oct 23 16:39:41 EEST 2005 mb@efe.enderunix.org:/usr/src/sys/i386/compile/EFE i386]. (c) Murat Balaban http://www.enderunix.org/ [pid: 1075] 04/12/05 16:27:20: Default matching algorithm: lfp 04/12/05 16:27:20: loadmodule: /usr/local/etc/voipong/modules/modvocoder_pcmu.so (@0x2817f3bc) 04/12/05 16:27:20: loadmodule: /usr/local/etc/voipong/modules/modvocoder_pcma.so (@0x281813e0) 04/12/05 16:27:20: loaded 2 module(s) 04/12/05 16:27:20: loadnet(10.30.0.11/255.255.255.255) method: fixed 40000 04/12/05 16:27:20: em0 has been opened in promisc mode. (192.168.1.0/255.255.255.0)
Start tcpreplay with the test capture you just downloaded at step 1.
[root@efe ~/calls/ok]$ /usr/local/sbin/tcpreplay -i em0 endercall2.pcap sending on: em0 4534 packets (1344595 bytes) sent in 141.44 seconds 9506.2 bytes/sec 0.07 megabits/sec 32 packets/sec
You will see that VoIPong immediately starts monitoring your call. Following lines will appear in your voipong.log file:
24/10/05 20:47:23: created a call recording instance! 24/10/05 20:47:23: [68826] VoIP call has been detected. 24/10/05 20:47:23: [68826] 10.0.0.145:49604 < -- > 10.0.0.200:49606 24/10/05 20:47:23: [68826] Encoding 0-PCMU-8KHz, recording.......
At the end of the call, you'll see that two .WAV files are created:
24/10/05 20:52:52: [68826] maximum idle time [10 secs] has been elapsed for this call, the call might have been ended. 24/10/05 20:52:52: [68826] .WAV file output/20051204/session-enc0-PCMU-8KHz-10.0.0.145,49604-10.0.0.200,49606.wav has been created successfully 24/10/05 20:52:52: [68826] .WAV file output/20051204/session-enc0-PCMU-8KHz-10.0.0.200,49606-10.0.0.145,49604.wav has been created successfully
# ls /var/log/output/20051024/ session-enc0-PCMU-8KHz-10.0.0.200,49606-10.0.0.145,49604.wav session-enc0-PCMU-8KHz-10.0.0.145,49604-10.0.0.200,49606.wav
You can play output files with several utilities including play, xmms etc.:
# play /var/log/voipoutput/20051025/session-enc0-PCMU-8KHz-10.0.0.145,49604-10.0.0.200,49606.wav