CAREFOR: Collision-aware reliable forwarding technique for vehicular ad hoc networks

This paper presents a new probabilistic-based re-broadcast scheme, providing a reliable and low-collision packet forwarding in a vehicular ad hoc network. In the proposed technique called Collision-Aware REliable FORwarding, each vehicle rebroadcasts a received information on the basis of physical parameters associated with a vehicular environment, i.e., the distance from the source, the density of neighbors, and the forward transmission range. The key idea is that a node implicitly evaluates the probability that there is another node which can be more successful in rebroadcasting, that means (i) the message will be transmitted as far as possible, and (ii) will have a low number of expected collisions. Unlike other existing probability assignment schemes, our technique attempts to accurately forecast the next-hop transmission, while keeping the computation cost very low.