A Lightweight Authentication with Dynamic Batch-Based Group Key Management Using LSTM in VANET

Table 1

Notations used in the protocol.

Notations	Descriptions
TA	Trusted authority
	ith roadside unit
	A finite field
q	A large prime number
	’s ID selected by TA during registration
	Secret key used between RSU and TA
	Secret key used to verify legality between RSU and vehicle
	jth vehicle
	Secret key of
	Random number selected by
	Timestamp selected by during authentication
	Random number selected by during authentication
	Denotes the emergency level of the message
	Random number selected by RSU to generate key
	The group key
M	The message sent by vehicle
	A list that contains legal RSUs’ identity