[asterisk-users] T38 fax detection using g729

[Larry Moore]

On 14/04/2011 7:25 AM, Niccolò Belli wrote:
> Il 13/04/2011 19:54, Larry Moore ha scritto:
>> That is because the remote endpoint, eutelia, will need to detect the
>> Fax Tones and send the T.38 ReINVITE to you, they may not have T.38
>> enabled.
> Uhm... it's very unlikely.
>

I made a suggestion on how you could check this i.e. have your incoming 
call go directly to the fax extension, my 1.8.3.2 installation 
immediately negotiates a T.38 connection in this sceanrio, of course I 
enabled the fallback option so it will use g711a if T.38 is not accepted 
by the peer.

>> As a suggestion you could configure your incoming calls from eutelia to
>> go directly to the fax receive function whilst having the g729 codec
>> enabled, I expect you will then see T.38 re-invite come from Asterisk.
> See attachment from bug https://issues.asterisk.org/view.php?id=19100
> Doesn't Eutelia send a T.38 re-invite there?
>

You did not make reference to this article in your original post, I 
viewed both log files in the article you referenced there, I would 
suggest you search for the word "udptl" and see if you can find where a 
T.38 negotiation occurred.

> Anyway I will check again making a packet dump to be sure.
>> What is in your configuration for 159?
The reason I asked this was because the log files I perused indicated 
this peer does not support UDPTL.

> [159]
> language=it
> type=friend
> qualify=yes ;ping per controllo stato
> dtmfmode = rfc2833
> context=phones-sip
> host=dynamic
> disallow=all
> allow=g729
> secret=mysecret
>

Larry.