Users' privacy at risk: From online identity tracking to real-life social relationship leakage

NYU Community Event

Speaker: Mohammed Ali (Dali) Kaafar, INRIA Grenoble


Record linkage is the process of identifying which records in two or more databases correspond to the same entity, and is an important aspect of data quality activities such as data-pre-processing and data integration. However, it can also be a powerful tool to invade users' privacy, in particular when considering that sources of information about individuals, increasingly collected in numerous locations, include many aspects of people's lives.

In this talk, we will take a closer look at the potential of information retrieval tools, and consider two use cases where record linkage techniques can be efficiently used for online and real-life profiling. We first investigate the feasibility of using usernames to trace or link multiple profiles across online services that belong to the same individual. The intuition is that the probability that two usernames refer to the same physical person strongly depends on the entropy of the username string itself. Second, we show how record linkage techniques can also be applied to exploit some information leaked by Active service discovery in Wi-Fi. We introduce the notion of WiFi fingerprints and show how we can exploit it to group the mobile devices to reveal social relationships that might exist between the owners of those devices. The techniques presented in this talk are widely applicable, and show that similarity evaluation enables tracking and profiling in different technology contexts.


Dr. Mohamed Ali Kaafar is a permanent principal researcher at the Privatics team at INRIA Grenoble, where he contributes to research in Security and Online Privacy. He is a visiting Professor at ICT-CAS in China and a principal researcher at NICTA Sydney, where he is on a sabbatical until mid 2013. Prior to joining INRIA in 2007, he was a post-doctoral researcher at University of Liege in Belgium. He obtained his PhD from INRIA Sophia Antipolis, where he contributed as a pioneer in the domain of Security of Internet Coordinate Systems. He leads several European and French Research projects. He has published in SIGCOMM, NDSS, PETS and he has served on the program committees of many major conferences. His current research interests include Privacy Enhancing Technologies, Online Social Networks, Mobile Networks, Internet Measurement, User Behavior Modeling, and Future Internet Designs with a focus on privacy and security.