Private Identification of Subscribers in Mobile Networks: Status and Challenges

The privacy of individuals in the context of mobile networks is crucial nowadays. Nevertheless, too few improvements have been made over the years to secure the privacy of subscribers. As a consequence, current generations of mobile networks, including 4G/LTE, are susceptible to sensitive information leakage. In particular, individuals are exposed to location disclosure and movement tracking by revealing subscribers' permanent identifiers. In this article, we discuss the subscribers' private identification problem in light of the recent standardization for 5G. We introduce the problem and discuss existing cryptographic solutions, with a focus on the ECIES-based solution adopted for 5G. We then investigate to what extent the privacy protection mechanisms introduced by the 5G security architecture answer our problem. Finally, we identify challenges, and we distinguish domains of interest and specific research activities to address these challenges.