Reliable data dissemination protocol for VANET traffic safety applications

In vehicular ad hoc networks (VANETs), cooperation between nodes is needed for proper performance of safety and traffic efficiency applications. A non-trivial scientific challenge in VANETs is the design of an adaptive broadcast protocol, which can provide efficient and end-to-end reliable warning messages dissemination. Usually, broadcast protocols for VANETs use beacon messages, disseminated among the vehicles, in order to get neighborhood information. When the vehicles are next to each other trying to broadcast at the same time, this may lead to frequent contention, and broadcast storms. On the other hand, in sparse density scenarios, vehicles have to face with failures in the message delivery. In this paper, we propose a novel protocol, Adaptive Data Dissemination Protocol (AddP), which aims at providing reliability to message dissemination in an efficient way. The protocol uses different mechanisms to dynamically adjust the beacon periodicity and to reduce the number of messages and beacons in the network. The effectiveness of our proposed protocol and the impacts of the use of the protocol by a VANET safety application were evaluated through experiments with network and traffic simulators.