Location-dependent and Context-Aware Computing

Background

Active Badge Location System is considered to be one of the earliest context-aware systems (Want et al, 1992). In this system, the user’s current location was determined by a series of infrared sensors and small wearable badges; the information about the user’s location enabled the system to forward telephone calls to the telephone closest to a particular user. In the following years, a number of other systems leveraging location context information were described in the literature, including systems receiving location information from the global positioning system (GPS) and from the communication infrastructure, e.g. Global System for Mobile communications (GSM) in cellular networks or WiFi access point connectivity in local area networks. In particular, location context was widely used to implement a number of context-aware tour guide applications (Abowd et al, 1997, Cheverst et al 200, Brown 1996, Kreller et al 1998, Fels 1998). Leonhard et al (1996) described a generic framework supporting location awareness based on a formally defined model of location; Indulska and Sutton (2003) and Becker and Durr (2005) provide comprehensive surveys of location management in context-aware systems.