Yet Another Answer to “Where am I?”

Computers and networks are becoming ubiquitous. The number of smart and mobile devices is increasing rapidly. Users become more mobile and their contexts change often and frequently. Simultaneously, users expect their devices, the applications, and infrastructures to be “smart”, i.e., they should support them when being mobile. Therefore, context data has to be used. However, because of the rapidly changing contexts and the underlying heterogeneity, the proper context is hard to find and to use. We propose a model for accessing context in a uniform and simple way across system boundaries and introduce context cells which provide an important schema for federating different contexts into a whole uniformly accessible system designed for mobile systems, as well as infrastructures supporting mobility.