Ringback Tone (RBT) Ringback Tone (RBT)

Ringback Tone (RBT)

Vonage API Support

Question

How does Ringback Tone (RBT) work with Vonage and how can it be configured?

Applies to

  • Voice API
  • SIP Trunking

Answer

Ringback Tone (RBT) is the audio a caller hears while a call is being connected (ringing). 

For SIP integrations: Vonage does not generate or inject Ringback Tone (RBT). Vonage only relays the SIP signalling received from the destination carrier or configured endpoint.

  • 180 Ringing response plays the default ringing tone.
  • 183 Session Progress response with SDP allows early media to be delivered, such as custom ringback audio or announcements.

For Voice API integrations: Custom ringback audio can be configured using the ringbackTone parameter in the NCCO.

Additional Information