REFER Pass-Through Call (REFER handled by User Agent)

The following illustration shows a REFER pass-through call using selective recording and the User Agent (UA) handling the REFER on the call. Recording is required in this call flow.

The REFER pass-through call handled by the UA call flow is described below.

UA-A sends INVITE to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller forwards INVITE with SDP Offer and metadata to SRS.
SRS responds with OK to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller sends INVITE to UA-B.
UA-B responds with OK to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller sends re-INVITE with SDP and metadata changes to SRS.
SRS responds with OK to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller forwards OK response to UA-A.
RTP stream initiated between UA-A and Oracle® Enterprise Session Border Controller.
RTP stream initiated between Oracle® Enterprise Session Border Controller and UA-B.
RTP stream initiated between Oracle® Enterprise Session Border Controller and SRS.
UA-A sends REFER-TO: C to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller forwards REFER-TO: C to UA-B.
UA-B responds with 202 ACCEPTED to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller forwards 202 ACCEPTED to UA-A.
UA-B sends INVITE TO: C to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller sends INVITE to UA-C.
UA-C responds with OK to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller forwards OK response to UA-B.
Oracle® Enterprise Session Border Controller sends NOTIFY with OK reponse to UA-A.
Oracle® Enterprise Session Border Controller sends re-INVITE to SRS with new SDP and metadata, adds participant C, stops participant A .
SRS responds with OK to Oracle® Enterprise Session Border Controller.
UA-A sends BYE to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller responds with OK to UA-A.
Oracle® Enterprise Session Border Controller responds with OK to UA-A.
RTP stream initiated between Oracle® Enterprise Session Border Controller and UA-B.
RTP stream initiated between Oracle® Enterprise Session Border Controller and UA-C.
RTP stream initiated between Oracle® Enterprise Session Border Controller and SRS.
UA-C sends BYE to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller responds with OK to UA-C.
Oracle® Enterprise Session Border Controller sends BYE to UA-B.
UA-B responds with OK to Oracle® Enterprise Session Border Controller.
Oracle® Enterprise Session Border Controller sends BYE to SRS
SRS responds with OK to Oracle® Enterprise Session Border Controller.