DTMF Audio to DTMF Audio

If the SDP offer and answer sides both support the same type of G711 codec, the audio stream is forwarded between the two sides without processing.

If the two sides of the call support DTMF audio tones, but use different audio codecs, and the SDP answer side supports the three DTMF Audio Tone conditions and does not support RFC 2833 then the Oracle® Enterprise Session Border Controller will preserve DTMF audio tone indication across the call.

Transcoding resources are used only if different audio codecs are used or the Override Preferred DTMF Audio feature is enabled.