Enjoying the benefits of GPS technology without giving up on privacy

GPS and other wireless location-based technologies are becoming more prevalent on cell phones and other devices people carry with them. GPS-based services to afford greater convenience, but they also allow a Big Brother-like tracking of individuals who use such services. Two researchers have now addressed the social reaction to constant surveillance, and they offer a way to avoid an Orwellian world. Computer scientists Bugra Gedik and Ling Liu explain that, while an Orwellian society is not right around the corner, location-based technologies have already raised major personal privacy issues. One case in point is DARPA’s LifeLog project, “a massive electronic database of every activity and relationship a person engages in,” which was recently scrapped due to privacy concerns. Gedik, a researcher at the IBM T. J. Watson Research Center, and Liu, an associate professor at the Georgia Institute of Technology, have recently developed a new technology that could protect cell phone and mobile device users from privacy abuse, while still enabling them to enjoy the benefits that location-based technologies have to offer. “We need to devise a location anonymization architecture that is both scalable in terms of achieving high anonymization success rate and high accuracy, and robust in terms of protecting users from vulnerabilities and threats of misuse and abuse of their location information,” Liu told PhysOrg.com, explaining one of the major challenges of developing a location privacy protection system.

Previous attempts at location privacy applications have been made, but Gedik’s and Liu’s system is the first to enable individuals to choose the level of anonymity for different applications, while still providing nearly optimal performance. For example, a cell phone user could send a request for a local gas station offering the most inexpensive gas to a location-based services (LBS) provider, and receive an accurate answer even without the provider knowing exactly where the user is located. Without knowing a user’s location, it would also be impossible for an LBS provider to determine with certainty a user’s identity when using the protective system. This protection is important since, using only location information, curious or malicious providers could conceivably determine information such as a user’s political affiliations, alternative lifestyles, medical problems, or the private businesses of an organization such as new business initiatives and partnerships, the researchers explained. The new system uses an anonymity-based approach called “location k-anonymity.” A user is considered to be location k-anonymous if their location information sent to the LBS provider is indistinguishable from the location information of at least k