Quality of forwarding-based data disseminating strategy in urban VANET

As for safety applications of vehicular Ad-hoc network (VANET), many valuable broadcast protocols have been proposed nowadays, most of which are based on either senders or receivers. In fact, sender-based protocols would fall into invalidation due to high mobility of network, while receiver-based ones would generate extra delay. Combining both the advantages of the two schemes, this paper proposes an efficient and reliable broadcast protocol based on quality of forwarding (ERBPQF) of candidate nodes. In ERBPQF, a double-phase relay scheme is presented to reach fast message dissemination in the first phase and to ensure high packet delivery ratio (PDR) in the second phase. Then, considering signal fading, channel contention, queuing delay, broadcast interference and high mobility of vehicles, a new metric called quality of forwarding (QoF) for relay selection is further proposed. The simulation results show that the delay and dissemination efficiency (DE) of ERBPQF outperforms slotted-1 protocol, accompanying with the achievement of more than 95% PDR.