Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

How to send DTMF in and out the RTP flow?

Using the "dtmf-relay cisco-rtp", the router removes the DTMF from the RTP flow to code there in separated packets.

If we use the “dtmf-relay rtp-nte” (IOS 12.2.XB) the DTMF are send only in RTP flow.

Is it possible to transmit the DTMF both IN and OUT the RTP flow? (For the same leg).



Cisco Employee

Re: How to send DTMF in and out the RTP flow?

As far as I know this can't be done. Can you explain why you would ever want to do this? Every time I have ever encountered a time where the DTMF tones were sent both in the RTP stream and in OOB signaling, this has tended to cause problems.

New Member

Re: How to send DTMF in and out the RTP flow?

We have a CRM system. We use an IVR that understands only the DTMF OOB. The DTMF are used to make some choices in a menu. But sometimes we need to forward the call to another IVR. (from US to Asia for example, to have a 24/7 SLA). When we forward the call, only the RTP flow is forwarded (without the DTMF). That's why we need the DTMF in the RTP flow too. No bad intentions here.

Do you have any idea if it will be implemented in future IOS release?

Thanks for your help.