A Critical Evaluation
The ever-growing incorporation of information technology in day-to-day applications presents new opportunities to develop computer systems that can be aware of the context in which they are operating. Such computer-systems can be inherently more responsive to the expectations of their users. Context-aware systems offer developers and programmers exciting new prospects to gather contextual data and adapt the behaviour of their dynamic systems according to user expectations. In conjunction with mobile devices, such mechanisms can be extremely valuable in increasing the usability of information systems. However, it is now accepted widely that the efforts to adapt the usability and capability of the desktop PC in to the mobile environment are limited in their scope. The debate in present literature seems to focus in particular on the trade-offs and compromises between the performance of such systems in theoretical or laboratory environments, and the actual results when tested in the field. This essay will aim to critically evaluate the success of making context-aware information systems into a feasible reality.
Context-aware computing is a general term used to refer to a class of mobile computer-systems that are able to sense the context they are being used in- that is to say, the physical environment in which they are being used in- and can adapt their behaviour in accordance to this context. The concept came forth from the model of ‘ubiquitous computing’ and was first proposed by Schilit et al at Xerox PARC in 1994. The three main factors in context are:
(1) User location vis-a-vis the physical environment
(2) Position relative to other users
(3) Resources available at that position
Context-aware systems include other persons, devices, and network/power resource levels etc that exist within that general physical environment (Schilit et al, 1994). They are also able to adapt their operations to the current context without any explicit inputs from the user - it is desirable in the field of mobile computing that programs and devices are able to gauge current location, time and other environmental attributes and react accordingly to the changing circumstances as context data may change rapidly. The context information that is needed may be gathered in a variety of ways, including applying sensors, network information, device status, browsing user profiles and other such sources (Baldauf et al, 2007).
Of course, in designing any context-aware system, it becomes necessary to define context, for which we turn to Dey & Abowd (2000)- “any information that can be used to characterize the situation of entities (i.e., whether a person, place or object) that are considered relevant to the interaction between a user and an application, including the user and the application themselves.”
The history of context-aware systems started when Want et al. (1992) introduced their Active Badge Location System which is considered to be one of the first context-aware applications. Schilit and his team, arguably the pioneers of this field followed up in 1994 with the PARCTAB, a small hand-held that used infrared-based cellular networks for communication. The device itself functioned mainly as an imaging terminal, with most of the computing done by remote hosts.