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Interactions of Preconditions with Session Mobility in SIP draft-camarillo-sip-rfc3312-update-00.txt. Gonzalo.Camarillo@ericsson.com. RFC 3312. RFC3312 assumes static sessions Each UA updates the current status of the direction it has local information about using offers
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Interactions of Preconditions with Session Mobility in SIPdraft-camarillo-sip-rfc3312-update-00.txt Gonzalo.Camarillo@ericsson.com
RFC 3312 • RFC3312 assumes static sessions • Each UA updates the current status of the direction it has local information about using offers • A UA cannot update the current status of the direction it does not have local information about • Answers cannot downgrade the current status • A UA cannot downgrade the current status of a direction if it does not have information about it
Introducing Session Mobility 3pcc A controller B C | | | | |<-dialog 1->|<-dialog 2->| | | | | | | *********************** | | |* MEDIA *| | | *********************** | | | | | | | | | | |<-dialog 1->|<------dialog 3----->| | | | | | ******************************** | |* MEDIA *| | ******************************** | | | | | | | | |
Update to RFC3312 • UAs should be able to downgrade the current status of a direction even if it does not have local information about it • UAs should be able to downgrade the current status of a direction in an answer
Backwards Compatibility • RFC3312-compliant implementations would not break • They would ignore downgrades • This situation would be the same as what we have today