GPS	Global Positioning System
LBS	Location-based service
HE	Homomorphic encryption
ABE	Attribute-based encryption
CP-ABE	Ciphertext-policy attribute-based encryption
KP-ABE	Key-policy attribute-based encryption
AES	Advanced encryption standard
DES	Data encryption standard
PLQP	Privacy-preserving location query protocol
DLP	Discrete logarithm problem
PPT	Probabilistic polynomial-time
DDH	Decisional Diffie–Hellman
DBDH	Decisional Bilinear Diffie–Hellman
CPA	Chosen plaintext attack
TA	Trusted authority