G729 not allowed on Inbound calls?

[tbrummell]

Why am I not able to use G729 on an inbound call? I c an use it on an outbound call just fine. You would think that if I was in a low bandwidth situation and required the use of 729 I could use it both ways, yet I cannot.

If I set my trunk:
disallow=all
allow=g729
I can place, but not receive.

If I set my trunk:
disallow=all
allow=g729&g711
I get the same results as above.

I have to remove any disallow/allow statements to get calls in.

Any Asterisk users have any input on this?

[laurent]

It's the same for everyone. Your device must accept the G711 codec to receive a call, plain and simple. You're allowed to switch to G729 for outgoing calls, but that's optional.

I've set my ATA to use G711 on both, because it sounds better than G729, and I still have more than ample bandwidth with my home DSL to support that.

[tbrummell]

I thought we had discussed this before! Turns out I was coming down with the flu and my mind was not at %100.

I'm not in a bandwidth limited situation either, but I like to have choices in case I ever am. I used NetAlly to run a bandwidth test on my connection, and the MOS drops to 3.9 after 6 simultaneous calls at 711. At 729 we ran it up to 20 calls and the MOS stuck at 3.9 the whole time (the max MOS for a G729 call). I wish the tool did G722 wideband so I could see the difference there, but it's not licensed for that.

[tbrummell]

I just realized, my origincal Q isn't answered. My config allows 729 & 711 with the line allow = g729&g711 yet FPL/Asterisk don't play nicely together with it. Since FPL tries to set the call up as 711, and the trunk is set to accept 729 & 711, it should work. I will need to post on the Asterisk forum for an answer I guess.

[laurent]

I believe in Asterisk, G711u/a codecs are named "ulaw" and "alaw" respectively, not "g711".

See: http://www.voip-info.org/wiki/view/Asterisk+codecs

[tbrummell]

Thanks Laurent, that was indeed it. As well, it follows the originating set (set originates 729, server to FPL is 729), which is perfect for me and my remote phone (it's on a limited b/w link). My remote set is able to answer FPL in calls, which are ulaw from FPL to server, then from server to remote it's 729, working fine. That explains why it wasn't working!

It would still be nice to force *all* inbound to G729 as an option. I see in our SIP profile there is an option for it "use preferred codec only" but we're not able to modify that. Maybe that's an option for a later date.

I wonder if Steve or Kris could chime in on that?

[tbrummell]

I guess Steve and Kris don't check this part of the forum.

[FONGO_steve]

At present time we prefer the use of g711u for highest call quality and interoperability with other VOIP-based systems and services. I am unsure if our developers will be able to change the inbound call negotiation codec in the long run or not.

[tbrummell]

That makes sense for the masses I guess. If it ever was implemented it would definitely require a warning about DTMF issues, that's my biggest hurdle with 729.