Hi, as Bob Penfield pointed in a previous mail, RFC3261 doesn't clarify if a 1XX response (that creates an early-dialog) MUST or not contain a "Contact" header (that would be need, for example, to send a BYE to terminate the early dialog instead of using a CANCEL).
Section 12.1 says: ------------------------------------ Within this specification, only 2xx and 101-199 responses with a To tag, where the request was INVITE, will establish a dialog. ------------------------------------ So it's clear that 12.1 put together "dialog" and "early-dialog" and calls them just "dialog". Sections 12.1.1 says: ------------------------------------ When a UAS responds to a request with a response that establishes a dialog (such as a 2xx to INVITE), the UAS MUST copy all Record-Route header field values from the request into the response (including the URIs, URI parameters, and any Record-Route header field parameters, whether they are known or unknown to the UAS) and MUST maintain the order of those values. The UAS MUST add a Contact header field to the response. ------------------------------------ Now in 12.1.1 it says that the UAS MUST add a Contact header if the response establishes a dialog. What is now a "dialog"? a real "dialog" (2XX) or both a real dialog and an "early-dialog" (1XX)? * Question: If it means both then any 1XX (non 100) MUST contain a Contact header, is it? But is also says that UAS MUST copy RR headers into the response, and this only makes sense in a 200 response, so: * Question: does 12.1.1 speak about a real "dialog" (2XX) or both a real dialog and an "early-dialog" (1XX)? Best regards and thanks a lot. -- Iñaki Baz Castillo <[EMAIL PROTECTED]> _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
