%0 Journal Article %T A Reliable and Efficient Highway Multihop Vehicular Broadcast Model %A Deng Chuan %A Wang Jian %J ISRN Communications and Networking %D 2012 %R 10.5402/2012/185472 %X A reliable and efficient highway broadcast model based on gain prediction is proposed to solve excessive information retransmission and channel conflict that often happen to flooding broadcast in vehicular ad hoc network. We take accountofthe relative speeds, the intervehicle distance, and the coverage difference of the neighboring vehicles into predicting the gain of every neighbor, and further select the neighbor with the maximum gain as the next hop on the every direction of road. Simulations show that the proposed model is clearly superior to the original flooding model and a recent variant based on mobility prediction in packet arrival rate, average delay, forwarding count, and throughput. 1. Introduction Vehicular ad hoc network (VANET) is a temporary autonomous system composed by a group of vehicles equipped with transceivers and global positioning system (GPS). VANET is specifically designed to communicate among vehicles so that drivers can acquire the information about other vehicles (e.g., speed, direction, and location) as well as real-time traffic information beyond visual range. The current main goal of VANET is providing safety and comfort for passengers [1].With this stream of research, highway safety has attracted more attentions, such as active accident warning, icy patch alarm, and others. Whether a successive collision can be effectively avoided is mainly dependent on transmitting warning information reliably and efficiently on multipaths. Due to limited transmission range of nodes, each mobile vehicle in VANET acts as router, for transmitting information to destination. Broadcast is a common means to disseminate messages. Among various broadcast approaches, flooding is the first one. Each node rebroadcasts the received message exactly once, which results in broadcast storm problems [2]. Although [2] proposes mechanisms to improve flooding, they are not effective for all range of node density and packet loads in VANET [3]. Therefore, multihop broadcast in VANET is faced with many challenges [4]. This work proposes a reliable broadcast routing based on gain prediction (RB-GP) in which the relative speeds and coverage differences of the neighboring vehicles are calculated, and the intervehicle distance is also considered, and thus the neighbor under consideration with gain and reliability is selected as the next hop on the every direction. Moreover, RB-GP switches to the storage and forwarding when there are not proper next hop temporarily, weakening the negative impacts caused by the serious topological segmentation in VANET [5]. The %U http://www.hindawi.com/journals/isrn.communications.networking/2012/185472/