A Redundancy based Protocol for Safety Message Dissemination in Vehicular Ad Hoc Networks

International audienceThe diversity of applications types in vehicular ad hoc networks (VANETs) has spawned a large variety of messages that need to be disseminated in vehicle to vehicle (V2V) communication mode. The most critical messages are those dedicated for safety applications such as accident warning, road hazardous warning, signal violation warning, etc. The dissemination of this sort of messages is a challenging task in VANETs since they should be efficiently transmitted i.e. by achieving high packet delivery within a certain time limit and an acceptable overhead. In this work, we propose a robust and an original data dissemination protocol called Redundancy-based Protocol (RBP). Contrary to most of the density based protocols, the protocol is beaconless. It takes into account the surrounding vehicle density during the broadcasting process through a specific metric, named “packet redundancy ratio”, calculated locally at each vehicle. Based on this metric, each vehicle is able to dynamically determine the probability of rebroadcast in order to mitigate the broadcast storm problem. The simulation results prove that the proposed protocol outperforms the slotted 1- persistence scheme in terms of packet drop ratio, and network load while still maintaining a low End-to-End delay and high packet reachability. This scheme is suitable for safety applications, as well as for further kinds of application by saving the network capacity consumption