Elaps: An Efficient Location-Aware Pub/Sub System

The prevalence of social networks and mobile devices has facilitated the real-time dissemination of local events such as sales, shows and exhibitions. To explore nearby events, mobile users can query a location based search engine for the desired data. However, operating under such a pull based model means that users may miss interesting events (because no explicit queries are issued) or processing/communication overheads may be high (because users have to continuously issue queries). In this demo, we present Elaps, an efficient location-aware publish/subscribe system that can effectively disseminate interesting events to moving users. Elaps is based on the push model and notifies mobile users instantly whenever there is a matching event around their locations. Through the demo, we will demonstrate that Elaps is scalable to a large number of subscriptions and events. Moreover, Elaps can effectively monitor the subscribers without missing any event matching, and incur low communication overhead.