How Vulnerable Is Vehicular Communication to Physical Layer Jamming Attacks?

There has been numerous studies on the security of vehicular networks, focusing mainly at higher layers of the network stack. Vulnerabilities of vehicular communications at the physical layer have not been explored thoroughly. To that end, we study internal and external vehicular communication under a variety of attack strategies involving jamming at the physical layer. We consider a couple of attack strategies, differing in how the attacker jams the resource blocks within a targeted spectrum. In particular, we focus on flat and random jamming, which are oblivious to the existing assignments and smart jamming, which senses the assignments and allocates power in frequency accordingly. For intra- vehicular setting, we consider an attacker attached to various locations within the vehicle. We used software-defined radios in an actual vehicle to emulate potential realistic attack setups and tested the effectiveness of various attack strategies. We show that, the smart jamming attack can lead to significant degradations in communication performance, to the extent of a complete blockage even with a low jamming power, in most setups. For external communication setting, we consider a busy intersection and study uplink communication in a multicellular LTE network. Using a system-level LTE simulator we developed, we show that a flat jamming attack by a static attacker can degrade the global performance significantly, while the smart jamming attack by a stalking attacker can almost block the communication initiated from a targeted vehicle. In short, we demonstrate via real-world experiments and system-level simulations that, with an appropriate strategy, the impact of a physical layer jamming attacker can be highly detrimental to both internal and external vehicular communication, seriously threatening the security of vehicular networks.