Abstract-Nowadays, researchers show more and more interests to Vehicular Ad hoc NETworks (VANETs), which are a specific instance of Mobile Ad hoc NETworks (MANETs) where nodes are vehicles. In VANETs, vehicles have no energy resource constraint which could extend coverage and network lifetime, but have a high mobility patterns that cause frequent and fast topology changes. Consequently, VANETs have particular research interests, like dedicated MAC and routing optimization. In our previous work, we have proposed MOvement Predictionbased Routing (MOPR) concept for VANETs, which improves the routing process by selecting the most stable route in terms of lifetime with respect to the movement of vehicles. And in this paper, we present how this MOPR concept can be applied to position-based routing protocols, and how it improves their performances. Based on simulation results we compare MOPR with the position-based routing protocol GPSR and another movement-based routing protocol called MORA.

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Abstract-Inter-Vehicular Communications (IVCs) are now considered as a way to realize active safety, for example, by providing the position information of each other or the potential danger warning by wireless communications.We have worked on a flooding protocol over vehicular ad hoc networks (VANETs) to efficiently disseminate the information for the sake of active safety applications, such as the positions and the velocities of the vehicles. We propose a flooding protocol with (i) Congestion Detection algorithm which suppresses unnecessary packets due to vehicular congested traffic and (ii) Backfire algorithm which efficiently forwards the packet through the network by selecting the adequate receiver node based on the distance from the original node.In this paper, we show simulation results over NS2 (Network Simulator 2). They show that the proposed flooding protocol significantly improves the performance of data dissemination over VANETS.

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Abstract-Wireless vehicular communications are attracting more and more interests for applied research in industries. Most of the efforts are spent in deploying Vehicular Mobile AdHoc Networks (VANETs) for applications such as active safety and Internet services. This paper addresses routing problem in VANETs for applications related to comfort and infotainment for users where an unicast routing protocol optimized for fast topology changes is needed. In previous research work, we have proposed a new movement prediction-based routing concept for VANETs called MOPR which we have already applied to the reactive routing protocol AODV in order to improve its performances by exploiting vehicules movements patterns. In this work, we first propose a new design of this concept, then we apply it to the OLSR routing protocol by optimizing the procedure of selecting the MPR (MultiPoint Relay) sets as well as that of determining the optimal path from each pair of vehicles. Basically, the connected MPR graph is composed of the most stable wireless links in the VANETs. We conduct several simulation scenarios to investigate the performance of the modified OLSR (OLSR-MOPR) by studying several metrics including the end-to-end average delay, the routing overhead, the packet delivery ratio, and the routing overhead ratio. The simulation results of the modified OLSR for various VANETs scenarios show great improvements comparing to the basic OLSR.