Dynamics of Network Connectivity in Urban Vehicular Networks

Vehicular ad hoc networks (VANETs) have emerged as a serious and promising candidate for providing ubiquitous communications both in urban and highway scenarios. Consequently, nowadays it is widely believed that VANETs will be able to support both safety and non-safety applications. For both classes of applications, since a zero-infrastructure is the typical premise assumed, it is crucial to understand the dynamics of network connectivity when one operates without relying on any telecommunications infrastructure. Using the key metrics of interest (such as link duration, connection duration, and re-healing time) we provide a comprehensive framework for network connectivity of urban VANETs. Our study, in addition to extensive simulations based on a new Cellular Automata Model for mobility, also provides a comprehensive analytical framework. This analytical framework leads to closed form results which facilitate physical insight into the impact of key system parameters on network connectivity. The predictions of our analytical framework also shed light on which type of safety and non-safety applications can be supported by urban VANETs.