| dc.description.abstract | Nowadays, mobile devices are commonly embedded with GPS, such as cell phones, PDAs, and Tablet PCs. This allows people carrying in these mobile devices to enjoy the convenience of location-based services. In LBSs, a user commonly sends its own location to query for POIs. However, the privacy of the location information is very important. If a user whereabout is monitored continuously, his/her activities can be easily inferred. To avoid the exposure of the user’s activity, the location information should be protected in location-based services.
The concept of cloaking has been introduced to protect the user’s location information. In cloaking system, an area containing the user’s location is sent to the server for query instead of the user’s true location. However, the traditional cloaking systems suffer from correlation attacks. By observing the traffic of the cloaking region, an adversary can eventually identify a particular client. To provide better location privacy protection, in this thesis we introduce the spy-based cloaking system. In our system, a number of spies are used as the disguise to protect the true identity of the client. The simulation results show that, albeit the higher communication overhead, the proposed spy-based cloaking system is able to provide a much stronger location information privacy protection against correlation attacks. | en_US |