Managing Calls Using IP Telephony
November 2009 225
Call Progress Values
Brooktrout Bfv API has mapped all possible IP call INVITE
responses to Bfv call progress values. See Table 9 for values for
functions that provide a final call progress value:
Table 9. Mapping of SIP responses to Bfv FCP values
SIP
response
code
Bfv final call Progress code
486 Busy here FCP_BUSY1
600 Busy everywhere FCP_ROBUSY
503 Service Unavailable FCP_SITINTC
180 Ringing FCP_RING1
200 OK (when in response to an INVITE
when SDP media type and subtypes are
image and T.38 respectively.)
FCP_ANSWER_TONE_DETECT