Sending DTMF Digits Notifications using SIP INFO Messages to SRS

You can configure the device to send DTMF digits notifications to the SIPREC SRS. These notifications are sent using SIP INFO messages. On the incoming leg (caller), all DTMF formats (i.e., RFC 2833, INFO, or in-band) are supported; on the outgoing leg (callee), only DTMF digits from SIP INFO messages are supported.

For example (assuming "A" is the caller):

"A" sends DTMF (any format): The device sends an INFO message to the SRS and to "B" (which must support sending and receiving INFO messages).
"B" sends DTMF in INFO message: The device forwards the INFO message to the SRS and sends the DTMF to "A" in the required format.
To send SIP INFO messages with DTMF to SRS:
1. Open the SIP Recording Settings page (Setup menu > Signaling & Media tab > SIP Recording folder > SIP Recording Settings).
2. From the 'Forward Signaling to SIPREC' drop-down list, select DTMF SIP INFO:

3. Click Apply.
The device adds the Remote-Party-ID header to the SIP INFO message that is sent to the SRS. The header's value is the URI of the sender of the DTMF digits.