1. A method for assuring location data integrity with minimum location disclosure comprising steps of: using Prefix-verifiable Message Authentication Codes (PMAC) to assure the integrity of the location data exchanged between a client device executing an authenticator and a verifier, wherein under the PMAC scheme, a variable-length prefix of the location data and a one-way-irreversible transformation of a corresponding suffix of the location data are presented to the verifier to allow the verifier to compute a result for comparing a received PMAC to verify the received prefix without compromising confidentiality of the suffix; using the PMAC from the previous step to authenticate/verify for spatial and spatio-temporal predicates; and using one or more message authentication codes indexes and one or more optimization techniques to reduce computation and communication costs; wherein the PMAC is generated via steps comprising: generating a symmetric key and securely sharing this symmetric key between the authenticator and the verifier; generating a random value of r; generating a PMAC value of the location data string x at timestamp t with respect to the symmetric key generated in the first step; and storing at least one tuple of (r, PMAC(x, t)) together with the location data string x and timestamp t on the client device executing the authenticator for authentication/verification.