Security and Connectivity Analysis in Vehicular Communication Networks

Reliable Vehicular Ad-Hoc Networks (VANETs) require secured uninterrupted uplink and downlink connectivity to guarantee secure ubiquitous vehicular communications. VANET mobility, multi-fading wireless, and radio channels could result in unsecured and disrupted vehicular communications, isolating some vehicle nodes and making them vulnerable to security attacks. A VANET is considered to be connected and secured if there is a secured path connecting any pair of Communication-Enabled Vehicles (CEVs) in this network. Among many parameters, VANET connectivity depends on two main elements: communication transmission range and statistical distribution characterizing inter-vehicle spacing. To guarantee persistent VANET connectivity, a vehicle transmission radio range must be set properly based on the characteristic of the statistical distribution modeling the inter-vehicle spacing. This chapter analyzes three inter-vehicle spacing models based on exponential, Generalized Extreme Value (GEV), and Exponential with Robustness Factor (EwRF) statistical distributions. Based on vehicle nodes spatial density on a road segment, each vehicle node can adjust its transmission range to increase network connectivity and guarantee ubiquitous vehicular communications. Communications among vehicle nodes are secured through trusted Road-Side Units (RSUs) which distribute efficiently secret keys to vehicle nodes under their coverage to establish secure communication sessions.