Privacy and Protection for Location Based Services

An LBS (location based service) provides services such as finding the nearest location, favourite entertainment areas etc, to the users based on either their residing area or based on the input the give. The services provided by a location based service are typically based on a point of interest database. Therefore retrieval of the data from the database server takes place. The work proposed is a novel protocol for location based queries that has major performance improvements, which is performed based on two stages- firstly, the user determining his/her location privately and secondly, the server protecting its data from unauthorized users for which they have not paid. This protocol enables security for the userrsquo;s details as well as protects the serverrsquo;s data. The user is protected because the server is unable to determine his/her location. In the same way, the serverrsquo;s data is protected as a Malicious user can only decrypt the part of data obtained to the user with the encryption key acquired in the previous phase, that is he/she cannot decrypt the remaining server data that they are not supposed to authorise. In other words, users can never get the data more than what they have paid for. A phase called oblivious transfer phase is present so as to ensure the privacy of the user and a phase called private information retrieval phase is carried out to protect serverrsquo;s data.