6/3/2015Sean Olson The PUBLISH Method Draft-olson-sip-publish-00

Sean Olson 6/3/2015 Overview A general purpose mechanism for publishing event state First application is presence publication Based on model for presence composition Defines new PUBLISH method New PType, PStream, PState Headers

Sean Olson 6/3/2015 A model for presence composition Event state is published to a “slot” identified by a token carried in the PType header. The slot identifies the context of the published data Publishing devices are distinguished by a unique identifier carried in the PStream header One or more devices can publish to the same slot Event state is soft-state with an expiration value carried in the PState header

Sean Olson 6/3/2015 A model for presence composition Presence Compositor PUA Composite Document Appl PUA Share the same “slot” or PType Differentiated by PStream A third party publishing on behalf of the user using a well-known Ptype (e.g. geoloc)

Sean Olson 6/3/2015 Example PUBLISH message PUBLISH SIP/2.0 Via: SIP/2.0/UDP pua.domain.com;branch=z9hG4bK652hsge To: From: ;tag=1234wxyz Call-ID: CSeq: 3242 PUBLISH Expires: 3600 Event: presence PType: mobile PStream: Content-Type: application/cpim-pidf+xml Content-Length:... closed

Sean Olson 6/3/2015 Open Issues Do we attempt to solve the CPL problem with the same model/mechanism? Is the slot concept the right way to go? Do we need to standardize the PType tokens? Should PType require IANA registration? Replace PState with Expires: header?