Low Bandwidth Codec Settings

Hi, does anyone know how to modify the codec settings in Asterisk to use G729 or G723. I want to get the most out of my bandwidth since I’m limited in upload. Currently, when I’m on a call I’m using roughly 85kbps.

Thanks.

Scott

g.729 requires a license and i believe 723 does too. Try gsm or ilbc codecs, they work pretty well…

if you dont want to buy a license and your voip carrier supports g.729 you can define g729 as a codec anyway, and asterisk will just pass it through (pass the encoded 729 data from one peer to the other without looking @ it). This may help although it will prevent the use of conferencing and a few other things…

Hi,

I believe the way is to disallow everything in your sip.conf and then specifically allow the ones that you like this:

[general]
disallow=all
allow=g729
allow=g726

Checkout the wiki topic here for more info:
voip-info.org/wiki/index.php … 20sip.conf

Thanks for the quick response guys. I tried the following in my sip.conf per the same article I read earlier and that pretty much killed my system. I had to set back to allow=ulaw and allow =alaw. Once I changed back it worked fine.

disallow=all
allow=g729
allow=g726

My present service provider is broadvoice so I’m guessing based on this test they do not support g729 or g726 and they’re not passing it on. How do I go about changing over to GSM or another low bandwidth codec.

Thanks.

Scott

In testing I changed the ulaw and alaw to just one allow=gsm and then rebooted. When the server came back online I received the following info in my event log…

Nov 21 16:35:41 NOTICE[2387] chan_sip.c: Peer ‘broadvoice.outbound’ is now REACHABLE! (32ms / 2000ms)
Nov 21 16:36:31 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:36:54 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:37:11 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:38:03 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:38:50 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:39:03 NOTICE[2387] chan_sip.c: No compatible codecs!
Nov 21 16:39:03 NOTICE[2387] chan_sip.c: No compatible codecs!

Does this mean that broadvoice is not supporting the gsm codec?

Well, so much for broadvoice. I was just scanning their site for codec info and apparently this is what they have to say…

BroadVoice currently support the G711u codec. BroadVoice intends to support others in the future, including G726-32 at 32kbps and G729a at 8kbps.

That sucks. I love their international service becuase we can make calls to europe which is covered in our monthly plan however my provider is killing me in upload speed. Does anyone know if the g726 or g729a are free non-license codecs?

Scott

g729 in all variants requires a license.

I believe that g726 does not. It as i recall is similar to g.711 (pcm ulaw/alaw) but uses ADPCM instead… * only supports the 32kbit/sec version (which is the only widely used one).