<div dir="ltr"><div dir="ltr">On Fri, May 20, 2022 at 11:30 AM Benoît Panizzon <<a href="mailto:benoit.panizzon@imp.ch">benoit.panizzon@imp.ch</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi Joshua<br>
<br>
> What is the specific issue that is happening? If it's that one call<br>
> leg negotiated at opus and the other at alaw, that is currently the<br>
> way things still work. Each call leg is still ultimately negotiated<br>
> independently so the A leg can be opus, and the B leg can be alaw. I<br>
> hope that we're able to eventually return to codec negotiation work<br>
> to improve that with the foundation put into place previously, but I<br>
> don't know when that will happen.<br>
<br>
It looks like I had some other misconfiguration also causing some weird<br>
effects.<br>
<br>
Well wheat I wonder is how codec negotiation should work in this<br>
situation.<br>
<br>
I am aware, the SDP defines what the device can send, not what it is<br>
able to receive. But can't we assume this is the same?<br>
<br>
Device A <=> Asterisk <=> TSP Trunk <=> [WORLD] <=> Device B<br>
<br>
Let's assume Device B is alaw only, but we don't know, it could also be<br>
possible of better quality codecs.<br>
<br>
Device A support opus,g711,alaw<br>
<br>
So towards Device A I would define !all,opus,g722,alaw<br>
And towards the TSP Trunk the same.<br>
<br>
But when Device B replies with an SDP containing 'only' alaw, shouldn't<br>
this SDP be passed to Device A which then hopefully use the same codec?<br></blockquote><div><br></div><div>Asterisk isn't a SIP proxy, so there is no passing of SDP. Each call leg is currently independent on the answer. So between Device A and Asterisk is negotiated separately from Asterisk and Device B. Each side can end up using different codecs, and Asterisk would transcode if possible.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Of course Device A can receive alaw and send opus. But device B might<br>
not understand opus.<br>
<br>
And I just realized, this advanced codec negotiation is only available<br>
on Asterisk 18. I'm still on 16 :-)<br></blockquote><div><br></div></div><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="font-family:tahoma,sans-serif"><font color="#073763">Joshua C. Colp</font></div><div style="font-family:tahoma,sans-serif"><font color="#073763">Asterisk Technical Lead</font></div><div style="font-family:tahoma,sans-serif"><font color="#073763">Sangoma Technologies</font></div><div style="font-family:tahoma,sans-serif"><font color="#073763">Check us out at <a href="http://www.sangoma.com" target="_blank">www.sangoma.com</a> and <a href="http://www.asterisk.org" target="_blank">www.asterisk.org</a></font><br></div></div></div></div></div></div></div></div></div></div></div>