DTMF Issue via SIP Trunk

[drbabbers]

All,

I have an inbound DDI delivery via a SIP Trunk, this DDI is matched in a dial peer and sent into CUCM. CUCM then has a match for this as a CTI Route Point which sends the call into CCX. When I dial the CCX trigger internally I can get through all OK, however when through the ITSP I get no DTMF tones working on the IVR.. I imagine the problem is something on our CUBE?

D

[j.huizinga · Accepted solution]

Needs problably MTP resource, or try different DTMF on the inbound dial-peer to the CUCM

I have a CUBE wqith UCCX and I use "dtmf-relay rtp-nte sip-notify"

Jan

[Flavio Alonso]

I changed the option in SIP-Trunk "DTMF Signaling Method" = "No preference", and it worked. Thanks by Tip.

[Chris Deren]

Jan is correct (+5), since CCX does not support inband RFC2833 DTMF method, you best option is to enable "dtmf-relay rtp-nte sip-notify" on inbound/outbound dial-peers to/from CUCM.

[drbabbers]

Thanks Jan + Chris I will give this a try and let you know.

D

[drbabbers]

This was resolved using a SIP Trunk between the 2 clusters instead of H.323 and also enabling the DTMF features on the SIP Trunk.

D

[drbabbers]

All,

I am still having problems with this.. Perhaps I didn't explain it correctly!

Call Flow is as follows:

ITSP->CUBE->CUCM->CCX->Transfer via Script to another CCX Trigger via the ICT

When I follow this call flow, the remote CCX doesn't accept any DTMF tones. (The 1st CCX I hit works fine with DTMF)

When I modify the call flow like this:

PSTN->H.323 GW->CUCM->CCX->Transfer via Script to another CCX Trigger via the ICT

It all works fine and the DTMF tones work perfectly.

So it is something to do with the delivery via SIP instead of H.323 with ISDN.

Any ideas?

D

PS: I have tried to enable MTP on the ICT at both ends and it doesn't seem to make any difference.

[avinsrid89]

Helo D,

This works in the H.323 scenario because H.323 generally uses alphanumeric or H245 signal as DTMF method. Both of these are out of band. CTI does not support in band DTMF, and by default uses out of band. No MTP is needed for OOB <-> OOB DTMF relay method.

SIP by default (if nothing else is explicity configured) uses RFC 2833 DTMF which is inband. Hence inband <-> OOb will invoke MTP from CUCM side.

If you share the traces, we can see why MTP allocation is failing or why MTP is failing to do the DTMF conversion. Or easiest fix is to use KPML or SIP NOTIFY on the CUCM <-> CUBE leg for DTMF.

~Avinash

[Chakshu Piplani]

Hi,

I have it working in my lab.

My dial-peer config going towards CUCM:

dial-peer voice 100 voip
 description for CCX
 destination-pattern ^6...
 session protocol sipv2
 session target ipv4:10.127.222.122
 dtmf-relay rtp-nte
 codec g711ulaw
 no vad

Make sure "Media termination point required" is checked on CUCM trunk page, if you want to save on resources use only software MTP in MRGL as I'm using the same.

Please share results.

Regards,

Chakshu Piplani

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[PRABAHARAN C]

Did you fix this issue? I am also facing the same problem

[Ritesh Desai]

prabharan,

If you've gone through thread properly, you may have found hint.

As Chris explained, inband is not supported. dtmf relay sip notify which is out-of-band dtmf signalling needs to be configured on router, inbound and outbound dial-peer towards/from CUCM.

regards,

Ritesh Desai

[PRABAHARAN C]

Ye. I have tried that command in both dial peer towards/from CUCM but it doesnt work. As baabage mentioned, when it goes to intial uccx greeting it does work after that when we trien any internal number which has pointed to another uccx trigger its not working. :(

Please suggest us.

[drbabbers]

I fixed by this:

'This was resolved using a SIP Trunk between the 2 clusters instead of H.323 and also enabling the DTMF features on the SIP Trunk.

D'