Vehicular ad hoc networks have been developed in consideration of advancing driving safety. In driving-safety\napplications, rapid dissemination of warning messages is highly demanded to avoid accidents involving incoming\nvehicles. Broadcast transmission is considered the most appropriate technique to spread warning messages because\nit can simultaneously reach all neighboring nodes within a transmission range using only a brief wireless media\naccess. However, blindly broadcasting redundant messages may severely overcrowd wireless media channels and\nprovoke transmission collisions; this is known as the broadcast storm problem. In order to reduce broadcast\nredundancy, broadcasting must be intelligently controlled. Simultaneously, an intelligent broadcast scheme should\naim to reduce the number of hops needed to arrive at a destination, to achieve smaller propagation delay. In this\npaper, we observed the behavior of a few broadcast schemes and found that their performances can be explained as\nlimiting a space to control the number of contentions in broadcasting. From the observation, we propose a limited\narea-based (LAB) scheme to achieve a shorter propagation time as well as a smaller number of redundant broadcast\nmessages. The proposed scheme can maintain a proper collision rate to obtain a faster propagation time by adjusting\nthe size of an area in which broadcasting nodes belong. Performance evaluation results from simulation show that the\nproposed scheme is feasible and reasonable.
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