Accessing Location Data in Mobile Environments ? The Nimbus Location Model

Location-based applications and services are getting increasingly important for mobile users. They take into account a mobile user’s current location and provide a location-dependent output. Often, location-based applications still have to deal with raw location data and specific positioning systems such as GPS, which lead to inflexible designs. To support developers of locationbased services, we designed the Nimbus framework, which hides specific details of positioning systems and provides uniform output containing physical as well as semantic information. In this paper, we focus on the location model, which takes into account the requirements of clients in mobile environments. A domain model contains logical links and allows the expression of semantic relations between locations. A decentralized and self-organizing runtime infrastructure offers operations to resolve the current location efficiently.