@techreport{garcia-simple-indirect-presence-publish-01, number = {draft-garcia-simple-indirect-presence-publish-01}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-garcia-simple-indirect-presence-publish/01/}, author = {Miguel Angel GarcĂ­a and Hannes Tschofenig and Henning Schulzrinne}, title = {{Indirect Presence Publication with the Session Initiation Protocol(SIP)}}, pagetotal = 11, year = 2009, month = mar, day = 6, abstract = {SIP is extended by the SIP-events framework to provide subscriptions and notifications of SIP events. One example of such event notification mechanism is 'presence' and this presence information is carried in Presence Information Data Format (PIDF) documents. The SIP PUBLISH method specified in RFC 3903 carrying a PIDF document is typically used when presentities publish their own presence since these presentities are typically the source of the information. However, there are cases when the presentity is not the direct source of the presence information. One such example is location information where the end host may obtain a reference to location information as opposed to as a value. The endpoint is typically not interested in knowing its own location information, but other users or entities might be. So, if the endpoint gets its own location information with a reference and wants to publish it embedded in its presence information, it first needs to de-reference it for getting a value, and then it can embed that value in its presence information. While this is certainly a correct sequence, it adds a round-trip to the presence publication, in addition to a demand processing power and network bandwidth consumption. There is a need for a mechanism that the presentity can use to publish indirect references, such as indirect location references. This document discusses a few variants that may be used to provide this functionality.}, }