Table 1.

Notation and their description.

Notation	Description
$TA$	The Trusted Authority
$OBU$	The On-Board Unit
$RSU$	The Road-Side Unit
$TPD$	The Tamper Proof Device
CRL	Certificate Revocation List
P	The base generator P ∈ $G_1$
$h_1,h_2,h_3$	Three secure hash functions
$I{D}_{vi}$, $Pwd$	Identity and password of vehicle
$TI{D}_{SV{P}_i}$	Vehicle’s true identity
$SVP$, $svp$	Short valid period of vehicle’s signature key
$svt$	Short valid period of vehicle’s true identity
${\delta }_{m_i}$, ${\delta }_{RJ}$	The message signature
${\zeta }_i$, k	Random integer
$s_{TA},P_{TA}$	The private/public keys of TA
$S{K}_{svt}$	The signature key of vehicle
⊕	XOR operator
${\gamma }_i$	a random vector
$m_i$	Safety traffic-related messages
‖	Concatenation operation
$ts$	Current timestamp