Intelligent Adjustment Forwarding: A compromise between end-to-end and hop-by-hop transmissions in VANET environments

Most of the nodes in a vehicular ad hoc network (VANET) move continuously, and thus the link quality changes constantly. As a result, the connections are intermittent and many network services (e.g., video conferencing) fail to function properly. Although many routing algorithms for discovering available transmission paths have been proposed, it is almost impossible to find a reliable end-to-end path in VANET environments since transmission failures occur so frequently. As a result, developing efficient retransmission schemes is of great practical importance. Accordingly, the present study proposes an application layer forwarding protocol designated as Intelligent Adjustment Forwarding (IAF), in which a segment-to-segment transmission paradigm is used to enhance the data delivery performance. The simulation results show that IAF not only improves the reliability of the data transmissions, but also enables a more efficient recovery in the event of transmission failures. Significantly, the improved transmission performance of IAF is accomplished with no more than a slight increase in the transmission time relative to that of existing VANET approaches.