SipReceivedProvisionalResponse

This event informs the application software that the far end SIP device has responded to an invitation to take part in a call. If your application does not care about other provisional event types but simple wants to know when the far end started to respond, you should process this event.

Note:
If your VOIP application uses a SIP proxy server, this event will be sent to the application when the call request is first processed by your proxy server and not by the SIP call endpoint.