Route lifetime analysis for vehicular networks

Vehicular communications have a critical role in the future intelligent transportation systems as they promise safer, more efficient and enjoyable driving. Multi-hop communications can be employed through routing protocols in order to achieve increased data transmission and coverage. However, most vehicular applications encounter significant challenges due to the increased mobility of the vehicles. This leads to transient communication links, which may significantly degrade the overall routing performance. Additionally, efficient routing techniques are required in order to achieve a reliable and flexible vehicular communications system. In this paper, we provide a framework for route lifetime analysis based on an exhaustive search routing technique to set an upper bound on the lifetime, which can inform the design of routing techniques. We then highlight the purpose of our framework by comparing the upper bound to a shortest-path forwarding mechanism based on global state routing (GSR), chosen as a routing example. The route lifetime is measured in order to reveal the trade-off between the structure and dimension of the road-network and performance requirements as a fundamental research baseline for investigating and developing sophisticated routing models for vehicular networks. Our results reveal that, on average, the shortest-path route lifetime is sub-optimal 11.56% of the time compared to the upper bound route lifetime. Then, we provide a trade-off between the road-network dimensions and the quality-of-service (QoS) requirements, and finally demonstrate that on average, under channel fading conditions, 7 times higher route lifetime could be achieved in a line-of-sight (LOS) scenario compared to its non-line-of-sight (NLOS) counterpart