Need quick suggestion on the dtmf method usage for the below call follow:
PSTN >> PRI >> VG >> MGCP >> CUCM >> SIP Trunk >> CUBE
VG supports - OOB
CUBE supports - RFC2833
DTMF on SIP Trunk configured as:
No Preference: Will the trunk utilize OOB as the dtmf method as being supported by the VG??
RFC 2833: When VG sends dtmf as oob to cucm and SIP trunk has rfc2833 configured. What will happen in this case ? What will the dtmf flow ??
OOB and RFC2833: Which method would be selected and why. If OOB is selected by looking at the VG's dtmf method, then there would be the MTP requirement due to the mismatch. Please correct if I am wrong.
I am pretty sure that the SIP trunk will use SIP NOtify for OOB DTMF,
I would suggest to use RFC2833 on the SIP trunk to the CUBE
Thank you for the quick response.
Yeah its true that OOB utilizes SIP Notify messaging. However, my concern is that what will happen in situation when SIP trunk is configured as either below:
oob and rfc2833
Note: Party 1 supports OOB while Party 2 supports rfc2833
thanks in advance...
well I have had a scenario where an inbound call from an MGCP gateway going to CUCM, then onto a SIP trunk got connected after about 40 seconds because the was no 3 way SIP handshake, this was caused by DTMF going from inband to OOB.
no preference : SIP TRunk will use SIP notify
RFC2833: SIP trunk will use in band signalling, through SIP SDP
OOB and RFC 2833: what I understand from it, is that it is capable of supporting both, but unclear of this requires MTP on the SIP trunk or not.
I am not sure of this answers your question
My experiece with setting both on the trunk was an MTP was still needed, I have a TAC case open and I am waiting on confirmation.