Privacy-Preserving Billing Scheme against Free-Riders for Wireless Charging Electric Vehicles

Table 1

Comparison with previous works.

	Feature	Location privacy	Price flexibility	Detect double spending	Prevent double spending	Avoid fraudulence in charging	Track illegal user	Avoid free-rider
[4]	Plug-in EV		not specified					Not concern
[5]	Plug-in EV						×^#	Not concern
[6, 7]	OLEV
[8]	OLEV
[9]	OLEV
Proposed scheme	OLEV

: the schemes for plug-in EV do not care about free-rider.
: the scheme can track a stolen vehicle with consent from its owner but cannot track illegal user.
: weak protection that CP can link all authentications of the same vehicle.