Introduction
G.729 is a toll-quality, low-bandwidth audio codec supported by many VoIP providers. The voice quality of a G.729-encoded call is about the same as that of G.711, the codec used for standard PSTN calls. However, the amount of bandwidth needed to carry a G.729 call is much lower than that for a G.711 call. Enterprises using G.729 will make more efficient use of available network bandwidth. G.729 uses roughly 1/8th of the bandwidth of a G.711 (8 kbit/s vs 64 kbit/s).
G.729 is available in two ways:
- Passthrough
- Transcoding
The passthrough method does not require licensing, however it has some limitations. For transcoding method G.729 license is necessary. Freeswitch offers a module and G729 license for transcoding G.729. Freeswitch's G.729 module supports Annex A and Annex B.
Obtaining License
Licences can be purchased from the FreeSWITCH website - see the G.729 tab at the top of the page.
Pricing is $10 per channel.
A single licence provides you with one encoder and one decoder, which is enough for bridging one call.
Licences are only required for channels performing transcoding (for bridging calls a leg uses G.729 and a different leg uses a different codec, and for applications which need to process media). Bridged channels where G.729 is on all legs still use pass-through mode, so that they do not consume a licence.
G.729 Module Installation
Download the fsg729-xxx-installer file from http://files.freeswitch.org/g729http://files.freeswitch.org/g729
| Code Block |
|---|
cd /usr/tmp wget http://files.freeswitch.org/g729/fsg729-xxx-installer chmod 755 fsg729-xxx-installer ./fsg729-xxx-installer |
G.729 License ActivitationRun the license validator:
usr/local/freeswitch/bin/validator
Enter the sales code you received from Freeswitch, licenses.zip file will be generated in the current directory. Unzip this file into /etc/freeswitch/
After unzip there will be xxxxxxxxxxxxxxxx.conf in the /etc/freeswitch
Freeswitch ConfigurationDisable the existing "mod_g729" by editing /etc/sipxpbx/freeswitch/conf/autload_configs/modules.conf.xml and add the "mod_com_g729":
<!‐‐ <load module="mod_g729"/> ‐‐>
<load module="mod_com_g729"/>