Privacy-preserving key distribution protocol based on PUF for vehicle-to-grid systems

In the past decade, Electric Vehicles (EVs) have slowly replaced traditional gasoline vehicles. EVs not only are environmental-friendly but also, when used in combination with the smart grid, open up new possibilities and enable the vehicle smart grid ecosystem, commonly referred to as Vehicle-to-Grid (V2G). This not only encourages the switch to eco-friendly EVs/Plug-in Hybrid Electric Vehicles (PHEVs) but also actively supports grid load management and is new to whole entities implicated in such ecosystems providing economic benefits. Nevertheless, the protection of privacy and security are still serious issues for smart grids. The types of equipment used in V2G are small, inexpensive, and limited in resources, so it is vulnerable to multiple attacks. Protocols designed for V2G systems must be safe, lightweight, and protect the privacy of vehicle owners. Physical security is also essential, as EVs and charging stations (CS) are generally not protected by humans. In order to solve these problems, we propose a Secure User Key-Exchange Authentication (SUKA) protocol based on Physical Unclonable Function (PUF) for V2G systems. The proposed protocol uses PUFs to implement two-step mutual authentication between the EV and the grid server. It's lightweight, safe, and privacy protected. The simulation shows that compared to other advanced V2G authentication protocols, our proposed protocol has better performance and provides more security features. Formal security models and analysis are used to demonstrate the security of the proposed protocol.