A time-critical information diffusion model in vehicle ad hoc networks

The diffusion of time-critical information, like traffic alert messages, is critical and challenging in Vehicle Ad hoc Networks (VANETs). It is critical because lives of people on the road are at stake and is challenging due to a combination of highly dynamic mobility patterns, which result in rapidly changing network topologies, combined with the fast movement of vehicles and highly dynamic traffic patterns. Flooding-based alert diffusion among vehicles has a strong similarity with diffusion of a new product among people. Applying a diffusion model to alert messages enables the dissemination modeling of the alert messages among vehicles, and thus opening an opportunity to adopt appropriate strategies to recovery from the traffic accidents. In this paper, a diffusion model is developed for a flooding-based alert message diffusion algorithm and the diffusion speed is explored. The fact that information value (or importance) is decreasing with time and distance, is also considered in the proposed model. We analytically investigate the impact parameters on time-critical information diffusion by mapping to the classic BASS diffusion model [1, 2]. The analytical model allows the evaluation at runtime and enables vehicles to dynamically adapt their diffusion strategies depending on the local node density.