Density-aware directional forwarding strategy for vehicular ad hoc networks

The characteristics of Vehicular Ad-Hoc Networks (VANETs) such as highly dynamic topology impose various challenges and constraints on routing protocols. These challenges should be managed effectively by the routing protocol. Geographic forwarding-based routing protocols are found to be effective in VANET, where geographic location information is utilized to select the next-hop for packet forwarding. Forwarding strategy is known as the core of such protocols to select the suitable forwarder among neighbouring nodes that can enhance the performance of routing strongly. Several research works have been developed to improve the forwarding strategy in VANET. However, some key issues such as utilizing the vehicle density to improve forwarding decision and reduce network congestion were not addressed. In this paper, an innovative forwarding strategy, called Density-aware Directional (DAD), with a joint consideration of vehicle density factor and directional forwarding is proposed for next-hop selection. It is aimed to manage the number of candidate next-hops as function of density and reduce routing loop by involving a directional angle. The proposed forwarding strategy was analyzed numerically to verify that it achieves the target properties.