Accessing Location and Proximity Information in a Decentralized Environment

Keywords: Location-based services, service infrastructures, positioning Abstract: Location-aware applications take into account a mobile user's current location and provide location-dependent output. Often, such 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 location-aware applications, 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 two important operations provided by the framework, described by two questions "Where am I? " and "What is in my proximity?" Our solution takes into account the requirements of clients in mobile environments. Our algorithms are based on a decentralized and self-organizing runtime infrastructure and are, thus, highly scalable and accessible for mobile users. We demonstrate the effectiveness of our approach by a number of simulations.