Roaming Electric Vehicle Charging and Billing: an Anonymous Multi-User Protocol

Abstract—In this paper, we propose a secure roaming electricvehicle (EV) charging protocol that helps preserve users’ privacy.During a charging session, a roaming EV user uses a pseudonymof the EV (known only to the user’s contracted supplier) whichis anonymously signed by the user’s private key. This protocolprotects the user’s identity privacy from other suppliers as wellas the user’s privacy of location from its own supplier. Further,it allows the user’s contracted supplier to authenticate the EVand the user. Using two-factor authentication approach a multiuserEV charging is supported and different legitimate EV users(e.g. family members) can be held accountable for their chargingsessions. With each charging session, the EV uses a differentpseudonym which prevents adversaries from linking the differentcharging sessions of the EV. On an application level, our protocolsupports fair user billing, i.e. each user pays only for his/her ownenergy consumption, and an open EV marketplace in which EVusers can safely choose among different remote host suppliers.