Fully Constant-Size CP-ABE with Privacy-Preserving Outsourced Decryption for Lightweight Devices in Cloud-Assisted IoT

Table 2

Notations for comparison.

Notations	Meaning
//	Size of element in the group //. mod p is a symmetric bilinear pairing.
	Time for a group exponential operation in (3.351 ms).
	Time for a group exponential operation in (0.538 ms).
	Time for a symmetric bilinear pairing mod p (5.325 ms).
	The number of rows of the LSSS matrix.
	The number of the attributes in system.
	The number of the attributes in the user’s attribute set.
	The bit string-based AND-gate access policy , where .
	The size of .
	The size of the set . is one subset of , that is, ; all the attributes in can satisfy the LSSS access policy.
	The threshold of the threshold policy.
	The number of the attributes in the threshold policy.