Presence Services for the Support of Location-Based Applications

Because of recent advances in both client devices and wireless communications, industry has started to look at the potentially relevant market of Location Based Services (LBSs). Several presence service proposals are putting together and standardizing interoperable the needed support for location data dissemination in industry-level LBS applications. However, the deployment of presence-based LBSs is still very challenging since frequent location updates have to be timely delivered to the (potentially many) subscribed LBS applications. The aim of this chapter is to clearly overview the main and still open technical challenges in currently available presence service standardization activities. In addition, by focusing on the most recent IP Multimedia Subsystem (IMS) and IMS-based presence service, the chapter presents an extensive survey of the state-of-art literature and proposes a novel and widely applicable architecture of solution for high scalability. Finally, the chapter also sketches the main presence-based LBS industry efforts nowadays and the currently open research issues.