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Session-Dependent Policies (1) Overview Policies are requested using MIO/MFO headers individually for each session during an offer/answer exchange. Defines a framework. Open issues Preconditions UAC may reject policies and terminate the session, which may cause “ghost rings” on the UAS side. Use of precondition could prevent “ghost rings”. Subsequent offer/answer exchanges How to handle policies in subsequent offer/answer exchanges? INVITE(offer) + MIO-1 INVITE(offer) + MIO-1 + MFO-1 OK(answer) + MIO-2 + MFO-1 ACK + MFO-2 OK(answer) + MIO-2 + MFO-1 + MFO-2 MFO-1 MFO-1 MFO-2 MFO-2 ACK + MFO-2 |