Context-aware Web Services for Distributed Retrieval of Points of Interest

Due to the widespread availability of accurate localization technologies, navigation systems are more and more present on mobile devices. These applications usually provide facilities for managing and searching points of interest. However, currently available navigation software does not support sharing of points of interest, and the search facilities are quite primitive, being exclusively based on location and categories. In this paper we present novel algorithms for context-aware retrieval of distributed resources. These algorithms can be executed on any unstructured peer-to-peer network, and are based on the distributed evaluation of a scoring function that takes into account a wide set of context data. The algorithms preserve the correctness of the result set until a certain time-to-live, while reducing the exchange of data in the network. The proposed algorithms have been integrated into a Web service-based, peer-to-peer system for management and sharing of an extended form of points of interest.