… system and subsequently discuss location privacy concerns, the … Afterwards, we identify the
objectives of location privacy … level of location privacy may require sacrificing service quality. …

… effective location privacy protection mechanism (LPPM) for LBSs without compromising the
quality of service. … In our proposed GCS, a querying user must be authenticated by the other …

… authentication of the server before making the payment is also necessary. Organization:
Section 2 describes the literature review of the location-based services … is compromised with the …

… authentication security of the system and then design a new location privacy protection
mechanism based on the privacy … without compromising their privacy [16]. Another definition of …

… are: (1) use of pseudonymous authentication for privacypreserving user authentication, (2) …
Without loss of generality, we assume that POI data in the LBS server is updated every TPOI , …

… location privacy, query content privacy, POI privacy and allows linking of query instances from
the same returning user without sacrificing … , location privacy, and authentication of the user…

… user privacy and authenticity are essential requirements for location based services in order
… and provide secure access to various services. Recently, numerous approaches towards …

… message authentication code, … without compromising the underlying security and privacy
requirements. However, to resist replay attack, it is required in [4] that the private authentication …

… infer the user’s location privacy and query privacy based on the … to construct an identity
authentication scheme between the … achieve privacy-preserving location-based services search …

… a Registration authority (RA) is used to provide authentication and authorization services to
the … Once the TTP compromises, all privacy will be leaked because the TTP knows all the real …