The many access devices with which a user directly interacts are the things that communicate. Telephones, fax machines, computers, television sets, ATMs, and pagers are examples of things that communicate. Access devices can move. Some access devices move with people, while some are only in occasional proximity to them. In either case, a location must be defined for the device if it is to be integrated into a context.
Current networks provide only inexact location information.
A device like a large printer, which moves infrequently, can have its location stored in a static database. But an active cellular phone, without triangulation, can be located no more exactly than within a cell capture area. Under any circumstances, the underlying systems of the NII must be supplemented by mechanisms to associate physical location and electronic location. In our model, services are the individuals or things with which a person communicates. One may exchange information with these services or get them to act on one's behalf.