I. Introduction
Today's transportation system is experiencing a revolution that significantly impacts people's lives. The increasing demands of safety, traffic capacity and energy efficiency impelled the emergence of new technologies. Examples of such technologies include vehicle sensing, hybrid drive systems, communication networks, etc., all aimed at enhancing the public desired performance in terms of efficiency and safety. It can be envisioned that the effectiveness of vehicle guidance and traffic management strategies will be amplified through Dedicated Short Range Communication wireless networks. These networks will operate among vehicles and between vehicles and roadway infrastructure (RI), named vehicular networks [1], [2]. In this venue, not only the drivers in vehicles have direct access to dynamic traveling related information, but also RI has more accurate situational awareness.