ReFleX aims at characterizing in a comprehensive manner the topological features of large-scale urban vehicular networks built on top of DSRC-based V2V and V2I communication technologies. To that end, the project adopts a multidisciplinary approach, bringing together tools from vehicular networking, wireless communications, transportation theory, and complex network science.The study will unveil the (yet largely unknown) vehicular network connectivity properties induced by a pervasive adoption of DSRC technolgies in urban environments. That way, ReFleX will evidence the strengths, weaknesses and overall capabilities of large-scale V2V/V2I communication systems, including their actual availability and reliability.In turn, the understanding of the basic features of the vehicular network topology will allow testing current protocols and architectures intended for DSRC-based networks, by verifying their fitness to the connectivity dynamics of large-scale urban vehicular networks. ReFleX will then take an original bottom-up approach to protocol desgin that puts the network connectivity at the core of the process, and it will propose enhancements and novel network solutions that adapt to the actual features of the network topology.