In 2022, I submitted and defended my dissertation on Privacy-preserving Geofencing at the Service-centric Networking chair of Technische Universität Berlin and Telekom Innovation Laboratories. It was published at TUB in the summer of 2023.In August 2021, I joined the project IDunion for the City of Cologne as an IT architect and researcher. The project, funded by the German Federal Ministry for Economic Affairs and Energy (BMWK), explores and researches Self-Sovereign Identity (SSI) approaches.In March 2012, I joined the Telekom Innovation Laboratories in Berlin as a doctoral candidate. As a research scientist in Prof. Dr. Axel Küpper's chair Service-centric Networking, I contribute to TRESOR, Curcuma, PARADISE, IdentityChain, DIMS, and IDunion. My main research areas are location-based services, applied security, privacy-preserving technologies, access control policies, self-sovereign identity, and distributed ledger technologies.In 2008, I started working as a research assistant at the University of Reading in England for nearly three years. I joined the EU-funded Hydra Middleware project (now LinkSmart middleware) in the School of Systems Engineering. My main focus was on security/policy aspects and context-awareness functionalities during the realization of the Hydra software, work on project demonstrators, and general research.In 2002, I finished my diploma thesis during a student identification and authentication project at the IT-Service-Center (now Zentraleinrichtung Campusmanagement) of the Technische Universität Berlin, where I worked as a student research assistant. The thesis's main focus was on e-mail encryption and smartcard security.After receiving my diploma, I continued working as a research assistant at the tubIT Service Center (ZECM) in Berlin. During this time, I contributed to security, policy, and access control projects like TUBIT and OBAN.My current research topics include:• Privacy-enhancing technologies• Digital verifiable credentials• Location-based services• Positioning and geo encoding systems• Applied cryptography• Attribute- based encryption• Cryptographic hash functions• Zero-knowledge proofs• Multi- party computation• Quantum computing• Distributed ledger technologies• Private set intersection• Linked data, semantics and ontologies