Spatial Data Infrastructure concepts for location based services-a case study in public transportation

Abstract

The introduction of wireless devices that facilitate communication 'anywhere, anytime' has been readilyembraced by society. Whilst offering alternative communication means with enhanced freedom and security thanthe fixed line telephone network, mobile phones are still limited by factors such as network coverage andhandset functionality (Cox 1996; Singleton 1983; Solymar 1999). Recent technological trends are resulting inthe functionality of organisation and assistant devices (such as Personal Digital Assistants) being combined withwireless communication methods (both voice and data based) one device can be used to record events, ring oremail colleagues and surf the Internet. Whilst network computing and the Internet in particular have evolved toremove the geographical emphasis of users, this new "nomadic computing and communications paradigm"(Leiner et al. 2000 WWW site) is reversing the situation, with user location now playing a critical role in theaccess and dissemination of information. The inherent link between wireless communication and location has thepotential to provide users with a range of services from personal safety (e.g. roadside assistance) through toconvenience or information services (e.g. guiding users from their current location to a restaurant of choice).Such services can be classified as Location Based Services (LBS).Location Based Services can rely on many diverse data sets, from relatively static road network information todynamic, real-time traffic flow information. Currently LBS developers must organise agreements betweenindividual data custodians, integrate these data sets and develop the application essentially establishing theirown infrastructure. To achieve a data sharing environment some form of framework is critical; this frameworkmust provide guidance on issues such as ownership, reuse, access, quality and cost. Spatial Data Infrastructures(SDI) are emerging as this framework and as a result, becoming useful to