Research On Routing Protocol Based On Link Stability For VANET

Vehicular Ad Hoc Network(VANET) is a temporary self-organizing network built by vehicles and road facilities. It is aimed at improving traffic safety and travel efficiency. The topology of VANET changes frequently due to vehicles’ continuous mobility pattern. In order to provide continuous and reliable transmission, this paper puts forward a VANET routing protocol based on the receiver competition and integrated metric. It is implemented on the OPNET network simulation platform. The main contributions of the paper are summarized as follows:(1) New routing metric method is designed. As vehicles are able to collect both topological information and geographical information such as speed and coordinates from adjacent nodes, this method quantifies the link remaining lifetime and the projection distance, then obtains routing metric through data fusion.(2) In the process of building the routing, receivers have dominant power in judging whether or not the forwarding node is themselves instead of senders. Different receivers compete for the right to forward data packets, according to the integrated routing metric. In this way, the production and propagation of network control information can be effectively limited.(3) As to routing maintenance phase, a local repair method based on the competition between upstream and downstream nodes comes up. The two nodes adjacent to link fracture compete for local repair rights according to their stability conditions. The more stable one will be chosen to repair the link.This helps reduce the possibility of secondary fracture. The simulation results show both the performance of packet delivery rate and transmission delay are improved without increase in the routing burden.(4) Two kinds of vehicular mobility models are proposed: urban road mobility model and urban intelligent transportation mobility model. These mobility models are important parts in Vehicular Ad Hoc Network. They contain a variety of vehicular elements about the rules and behaviors of lanes,drivers and vehicles so that the mobility model can be close to the reality.Three characteristics, including packet delivery rate, end-to-end delay and the route overhead are used to evaluate network performance.Results indicate that this protocol can effectively improve network performance in the vehicular environment.