RFC 3343 (rfc3343) - Page 2 of 23
The Application Exchange (APEX) Presence Service
Alternative Format: Original Text Document
RFC 3343 The Application Exchange (APEX) Presence April 2003 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 22 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 22 Full Copyright Statement . . . . . . . . . . . . . . . . . . . 23 1. Introduction This memo describes a presence service that is built upon the APEX [1] "relaying mesh". The APEX presence service is used to manage presence information for APEX endpoints. APEX, at its core, provides a best-effort datagram service. Within an administrative domain, all relays must be able to handle messages for any endpoint within that domain. APEX services are logically defined as endpoints, but given their ubiquitous semantics they do not necessarily need to be associated with a single physical endpoint. As such, they may be provisioned co-resident with each relay within an administrative domain, even though they are logically provided on top of the relaying mesh, i.e., +----------+ +----------+ +----------+ +---------+ | APEX | | APEX | | APEX | | | | access | | presence | | report | | ... | | service | | service | | service | | | +----------+ +----------+ +----------+ +---------+ | | | | | | | | +----------------------------------------------------------------+ | | | APEX core | | | +----------------------------------------------------------------+ That is, applications communicate with an APEX service by exchanging data with a "well-known endpoint" (WKE). APEX applications communicate with the presence service by exchanging data with the well-known endpoint "apex=presence" in the corresponding administrative domain, e.g., "apex=presence@example.com" is the endpoint associated with the presence service in the "example.com" administrative domain. Note that within a single administrative domain, the presence service makes use of the APEX access [3] service in order to determine if an originator is allowed to view or manage presence information. Rose, et al. Experimental



