An Adaptive Peer-to-Peer Overlay Scheme for Location-Based Services

One envisioned distinctive feature of smart cities is the interconnection among mobile users and vehicles, to support the fulfillment of location-based services. This can be obtained with centralized architectures, and with all the problems of scalability and robustness that such a solution involves. On the other hand, a more complex but more reliable, completely distributed approach can overcome this kind of problems. In this paper, we present the Adaptive Distributed Geographic Table (ADGT), a peer-to-peer overlay scheme suitable for the development of location-based services. In particular, the ADGT allows to efficiently retrieve peers or resources, to broadcast messages within any geographical region, and to be automatically notified about any type of information around any geographical location, following the publish/subscribe model. What mainly differentiates the ADGT from the other solutions in literature is the adaptivity of the overlay's topology to peers' mobility. Actually, the ADGT has the capability to adapt the neighborhood of each mobile peer depending on speed and direction. We have evaluated the ADGT by simulating different scenarios, and the results show that it acts well, ensuring high quality of messages dissemination and low cost in terms of data usage.