Table 1.

Notations and description.

Notations	Descriptions
Fp	Finite field
E	Elliptic curve defined on Fp with large order
P	Point on E
G	Group of elliptic curve points on E
H (.)	One-way hash function
S	RA's private key
IDu	Identity of user
IDt	Identity of the “thing”
RA	Registration authority
HRA	Home registration authority
IoT	Internet of Thing
ECC	Elliptic curve cryptosystem
RBAC	Role based access control