Leon Janzen, M.Sc.

Disaster scenarios can disconnect entire cities from the core network (CN), isolating base stations (BSs) and disrupting the Internet connection of app services for many users. Such a disruption is particularly disastrous when it affects critical app services such as communication, information, and navigation. Deploying local app servers at the network edge can solve this issue but leaves mobile network operators (MNOs) faced with design decisions regarding the criticality of traffic flows, the BS topology, and the app server deployment. We present the Crisis and Resilience Evaluation Tool (CARET) for crisis-mode radio access networks RANs, enabling MNOs to make informed decisions about a city's RAN configuration based on real-world data of the NetMob23 dataset.

Modern smartphones support FIDO2 passwordless authentication using either external security keys or internal biometric authentication, but it is unclear whether users appreciate and accept these new forms of web authentication for their own accounts. We present the first lab study (N=87) comparing platform and roaming authentication on smartphones, determining the practical strengths and weaknesses of FIDO2 as perceived by users in a mobile scenario. Most participants were willing to adopt passwordless authentication during our in-person user study, but closer analysis shows that participants prioritize usability, security, and availability differently depending on the account type. We identify remaining adoption barriers that prevent FIDO2 from succeeding password authentication, such as missing support for contemporary usage patterns, including account delegation and usage on multiple clients.