Gateway selection techniques in heterogeneous vehicular network: Review and challenges

The increasing QoS demand of vehicular network applications forces the integration between the vehicular ad-hoc network (VANET) and the cellular network infrastructure. However, due to the resource scarcity faced by the cellular network elevates the needs of offloading cellular data by defining the mobile gateway vehicles that will aggregate other vehicles traffics and communicate to the cellular infrastructure. This helps to reduce the overload problem that currently faces by the cellular operators. However, selecting mobile gateway vehicle in highly dynamic environment like VANET is a challenging task. Therefore, this paper reviews different mobile gateway selection techniques proposed in the literature. The reviewed techniques were grouped into cluster and non-cluster based depends on the organization of vehicles before the gateway selection process takes place. Besides, the challenges and open issues raised by reviewed techniques were deeply discussed.