Privacy preserving and content-protecting location based queries
1. PRIVACY-PRESERVING AND CONTENT-PROTECTING
LOCATION BASED QUERIES
ABSTRACT:
In this paper we present a solution to one of the location-based
query problems. This problem is defined as follows: (i) a
user wants to query a database of location data, known as Points
Of Interest (POI), and does not want to reveal his/her location to
the server due to privacy concerns; (ii) the owner of the location
data, that is, the location server, does not want to simply
distribute its data to all users. The location server desires to have
some control over its data, since the data is its asset. Previous
solutions have used a trusted anonymiser to address privacy, but
introduced the impracticality of trusting a third party. More
recent solutions have used homomorphic encryption to remove
this weakness. Briefly, the user submits his/her encrypted
coordinates to the server and the server would determine the
user’s location homomorphically, and then the user would
acquire the corresponding record using Private Information
2. Retrieval techniques. We propose a major enhancement upon
this result by introducing a similar two stage approach, where
the homomorphic comparison step is replaced with Oblivious
Transfer to achieve a more secure solution for both parties. The
solution we present is efficient and practical in many scenarios.
We also include the results of a working prototype to illustrate
the efficiency of our protocol.
EXISTING SYSTEM:
The first solution to the problem was proposed by
Beresford, in which the privacy of the user is maintained by
constantly changing the user’s name or pseudonym within some
mix-zone. It can be shown that, due to the nature of the data
being exchanged between the user and the server, the frequent
changing of the user’s name provides little protection for the
user’s privacy. A more recent investigation of the mix-zone
approach has been applied to road networks. They investigated
the required number of users to satisfy the unlinkability property
when there are repeated queries over an interval. This requires
3. careful control of how many users are contained within the mix-zone,
which is difficult to achieve in practice. A complementary
technique to the mix-zone approach is based on k-anonymity.
The concept of kanonymity was introduced as a method for
preserving privacy when releasing sensitive records. This is
achieved by generalisation and suppression algorithms to ensure
that a record could not be distinguished from (k − 1) other
records. The solutions for LBS use a trusted anonymiser to
provide anonymity for the location data, such that the location
data of a user cannot be distinguished from (k − 1) other users.
DISADVANTAGES OF EXISTING SYSTEM:
· As solutions based on the use of a central anonymiser are
not practical.
· This incurs both processing and communication overhead
for the user device.
PROPOSED SYSTEM:
4. In
this paper, we propose a novel protocol for location based
queries that has major performance improvements with respect
to the approach by Ghinita. Like such protocol, our protocol is
organized according to two stages. In the first stage, the user
privately determines his/her location within a public grid, using
oblivious transfer. This data contains both the ID and associated
symmetric key for the block of data in the private grid. In the
second stage, the user executes a communicational efficient PIR,
to retrieve the appropriate block in the private grid. This block is
decrypted using the symmetric key obtained in the previous
stage. Our protocol thus provides protection for both the user
and the server. The user is protected because the server is unable
to determine his/her location. Similarly, the server’s data is
protected since a malicious user can only decrypt the block of
data obtained by PIR with the encryption key acquired in the
previous stage. In other words, users cannot gain any more data
than what they have paid for. We also provide
5. results from a working prototype showing the efficiency of our
approach.
ADVANTAGES OF PROPOSED SYSTEM:
· This idea was extended to provide database protection.
· PIR is used to retrieve the data contained within the
appropriate cell.
· It is more efficient.
7. SYSTEM CONFIGURATION:-
HARDWARE REQUIREMENTS:-
Processor - Pentium –IV
Speed - 1.1 Ghz
RAM - 512 MB(min)
Hard Disk - 40 GB
Key Board - Standard Windows Keyboard
Mouse - Two or Three Button Mouse
Monitor - LCD/LED
SOFTWARE REQUIREMENTS:
• Operating system : Windows XP
• Coding Language : Java
• Data Base : MySQL
• Tool : Net Beans IDE
8. REFERENCE:
Russell Paulet, Md. Golam Kaosar, Xun Yi, Elisa Bertino, “Privacy-Preserving
and Content-Protecting Location Based Queries” IEEE TRANSACTIONS ON
KNOWLEDGE AND DATA ENGINEERING, 2012 IEEE 28th International
Conference on Data Engineering.