Slsr: A Flexible Middleware Localization Service Architecture

Location information of mobile devices is a foundational input to location-based services and a valuable source of context information in wireless networks. To maximize the value, we need location information that is accurate, robust, and promptly and seamlessly available. Unfortunately, individual localization services seldom satisfy all these requirements. For achieving that vision, a set of challenges has to be addressed, pertaining to handover, fusion, and integration of different sources of location information. Current approaches for integration of individual localization services are either not specific enough or are limited in scope and lack flexibility. In the following, we provide a detailed design and a prototypical implementation of the Standardized Localization Service (SLSR), a middleware architecture for achieving those goals. We instantiate the service in an office environment and perform exhaustive performance benchmarking in a testbed specifically designed for supporting such experimentation. Our results characterize the effects of different functional components envisioned in the SLSR on its performance. Our results also quantify the accuracy benefits of fusion of representative sources of location information.