Rathje, PatrickPatrickRathjeLandsiedel, OlafOlafLandsiedel2025-02-052025-02-052021-02International Conference on Embedded Wireless Systems and Networks, EWSN 2021: 18978-0-9949-8865-2https://hdl.handle.net/11420/53871Contact tracing helps to predict and prevent the spread of viruses. This work proposes Tracey for decentralized, privacy-preserving tracing. Unlike automated tracing solutions that operate in the background, such as the widespread governmental Corona Tracing Apps, our system builds on manual contact exchanges to ensure reliable contact tracing even for groups and venues. The devices share secrets that allow anonymous notifications using the health authorities’ trusted database. This work illustrates the concept, provides initial security analysis, first results, and gives an outlook on possible extensions.enTechnology::600: TechnologyConference PaperConference Paper