@InProceedings{delgado2026mum1, author = {Delgado Rodriguez, Sarah and Kastrup, Swantje and Wagner, Maximilian and Hemauer, Eva and Alt, Florian and Gutfleisch, Marco}, booktitle = {Proceedings of the 25th International Conference on Mobile and Ubiquitous Multimedia}, title = {Carrying Secrets: Exploring Security Perceptions of Physical Transport Devices}, year = {2026}, address = {New York, NY, USA}, note = {delgado2026mum1}, publisher = {Association for Computing Machinery}, series = {MUM '26}, abstract = {Physical transfer of sensitive data (e.g., on a flash drive) remains common but exposes users to unique risks, including loss, tampering, and substitution. Security in such contexts depends on users' ability to assess these risks correctly. However, it remains unclear how design cues impact security judgments. Addressing this gap, we explore how security perceptions are shaped by user interactions, form factors, and security features of physical data transport devices with two complementary studies. First, we elicit user visions of secure physical data transport, instantiate recurring concepts in five prototypes, and evaluate them in a user study (N=16). Second, we evaluate five commercially available devices (N=13) to surface the impact of security and authentication methods. Our findings suggest that usability correlates with trust, tangibility increases perceived security, and users focus on availability and integrity-related considerations. We discuss divergences between perceptions and plausible threats, and derive takeaways for the design and adoption of future physical transport devices.}, doi = {10.1145/3861188.3861222}, isbn = {9798400727917}, keywords = {security perception, tangible security, data transport}, location = {Glasgow, United Kingdom}, numpages = {16}, timestamp = {2026.11.08}, url = {http://www.florian-alt.org/unibw/wp-content/publications/delgado2026mum1.pdf}, }