Data dissemination framework for vehicular ad hoc networks

Vehicular Ad Hoc Networks (VANET) is an emerging field as a real life application of Mobile Ad Hoc Networks (MANET) which aims to improve safety and comfort of transportation systems. Considering the restrictions and characteristics of VANETs, it is observed that vehicle localization and packet routing algorithms which are specifically designed for MANETs are not suitable, efficient and directly applicable to VANETs. In our dissertation, we developed a data dissemination framework for VANETs that is composed of three main parts. The first is the destination vehicle location discovery algorithm which is a reactive, distributed and lightweight method that considerably reduces the number of broadcast messages by constructing forwarding regions and suppressing broadcast. Secondly, on top of the underlying location discovery operation, a novel pure reactive non-delay tolerant VANET routing protocol is introduced. The main contribution of the proposed protocol is the continuous maintenance of routing paths by intelligent usage of traffic awareness and network connectivity. In order to investigate the benefits of the fixed infrastructure and to have a comprehensive data dissemination framework, it is essential to include a Road Side Unit (RSU) based VANET routing protocol. Therefore, thirdly, a fully distributed RSU based VANET routing protocol is proposed. This algorithm consists of vehicle to RSU registration, handover processes, guided broadcast, broadcast suppression, route establishment, data packet transmission, and route maintenance. The presented methods are compared against recent and prominent algorithms using comprehensive simulations. The experimental results indicate the superiority and validity of the presented schemes.