[asterisk-users] Nortel pbx & dtmf issues

[Watkins, Bradley]

> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com 
> [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of 
> Ernest Byaruhanga
> Sent: Thursday, July 02, 2009 4:10 AM
> To: asterisk-users at lists.digium.com
> Subject: [asterisk-users] Nortel pbx & dtmf issues
> 
> folk,
> 
> I see from the archives that the issue of nortel handsets not
> sending dtmf tones to asterisk has been discussed a couple of times,
> but there is something I quite havent seen answered yet.
> 
> Is this dtmf issue a problem with the nortel handsets or the PBX
> itself? If the handset were changed to another one, would this issue
> be solved? Or must the PBX be changed completely?
> 

The only issue that I've experienced with respect to DTMF and a Nortel
PBX is when using SIP trunking.  Nortel used/uses (newer versions of
CS1000 software, 5.0 and newer IIRC, can use RFC2833-based DTMF) a
proprietary SIP INFO-based DTMF.  As it stands, Asterisk is capable of
receiving and interpreting those messages properly.  But sending DTMF to
the Nortel is an issue without code modification.

If you have a specific need for that, the changes themselves are fairly
trivial, and I can detail those for you if you'd like.  I might even
have a patch laying around that would work or could be made to work,
since we needed to integrate into an older version of the CS1000
software (since upgraded, so our current system passes DTMF via
RFC2833).

- Brad