On latency-aware tree topology construction for emergency responding VANET applications

Largely speaking, Vehicular Ad-hoc Network (VANET) is a special type of Mobile Adhoc Network (MANET), which has been a subject of numerous investigations over last decades. Topology control is an effective strategy to control network latency and improve energy efficiency of various types of MANET. VANET has several unique characteristics, and therefore it is not straightforward for VANET to adopt an existing topology control strategy for MANET. This paper introduces a new coordination algorithm to construct a tree topology for emergency responding VANET, which is highly dynamic by nature. Specifically, the algorithm computes a rooted tree topology among VANET nodes, which are highly mobile but voluntarily reveal their short-term future travel plans. The resulting tree topology is maintained for a certain time period while putting the communication latency under control, and therefore is highly useful for a government entity to collect realtime information of an emergency scene and distribute notifications to citizens in a timely manner. Using simulation, we verify the effectiveness of our approach.