User Privacy in Mobile Networks: Tracking, Robocalls, and Emerging Solutions - Dr. Yang Xiao

Abstract: Mobile cellular technologies, from 2G to 5G, have provided unprecedented network coverage and communication bandwidth to subscribers. While enjoying the connectivity and convenience, mobile subscribers are facing ever-increasing privacy risks, as reflected in recent security breaches at major Mobile Network Operators (MNOs), commonly known as carriers, which have led to violations of subscriber privacy and the rampancy of robocalls and scams. In this talk, we study the root causes of these privacy risks, including (1) MNOs capability of tracking/profiling mobile users and (2) caller ID spoofing based on the Voice over IP (VoIP) infrastructure. Then, we show our recent research efforts toward addressing these privacy problems while maximally preserving the existing mobile network utilities and regulatory compliance. Our approach essentially leverages emerging cryptographic techniques including Verifiable Credential (VC) and Zero-Knowledge Proof (ZKP) as well as insights into the mobile network core functions. Lastly, we discuss the possibility of generalizing our approach to wider mobile application scenes concerning accountable user authentication and tackling the trilemma between privacy, accountability, and usability.