Mapcast: A map-constrained broadcast solution for VANETs

Solutions for Vehicular Ad-Hoc Network (VANET) are challenging due to the intrinsic nature of the network which involves, by definition, node mobility, scarce or null fixed nodes and, at the current state of art, lack of solutions for the real-time tracking of positions. Moreover VANETs are meant to provide primarily a solution for the improvement of road safety, by the proper forwarding of messages: this makes the overall service scenario even more critical due to the delay-constraints and the scalability issues. While some solutions have already been proposed in literature to optimize message multi-hop forwarding based on mutual positions of nodes and exploiting CSMA/CA MAC mechanisms, in this paper a novel solution is presented: it extends the intuitive concepts of Geo-Broadcast (that is, broadcast forwarding based on distances) towards a more precise idea of Map-Driven forwarding (or Mapcast), where the real-life road topology leads forwarding policies. Mapcast solves some issues left open by previous art and simulatively shows interesting potentials.