Multiple Points of Presence (MPOP)

A great post on MPOP in OCS is available at the UC Team blog...

Lets examine some terminology that will be useful to us to understand MPOP. The user that publishes presence information is a presentity, whereas the users that consume this presence information are called watchers.

A point of presence is a client that explicitly provides presence information on behalf of a user (presentity). OCS2007 supports a variety of clients ranging from the soft-client Office Communicator 2.0 to Office Communicator Phone Experience.

https://blogs.technet.com/uc/archive/2007/03/01/multiple-points-of-presence-mpop.aspx