Hovering Information - Infrastructure-Free Self-Organising Location-Aware Information Dissemination Service1

This paper proposes a location-based service for disseminating geo-localised information generated by and aimed at mobile users. The service itself works in a self-organising manner. A piece of hovering information is attached to a geographical point, called the anchor location, and to its vicinity area, called the anchor area. It is responsible for keeping itself alive, available and accessible to other devices within its anchor area. Hovering information uses mechanisms such as active hopping, replication and dissemination among mobile nodes to satisfy the above requirements. It does not rely on any central server. Previous results involving a single piece of hovering information have shown the interest of the concept. This paper reports on a series of simulations involving multiple pieces of hovering information. Our goal is to investigate the scalability of the technique up to 200 pieces in a small geographic area. Two main replication algorithms for pieces of hovering information are compared, an Attraction Point algorithm and a Broadcast-based one. These replication algorithms are combined with two different caching policies, Location-based and Generation-based, for discarding hovering information pieces from mobile nodes buffer when memory is not enough.