I am privacy researcher, currently working as a Post Doc with the <a href="www.ou.nl">Open University of The Netherlands</a>.<br/> I finished my PhD on the security of wireless communication technologies such as GSM, GPRS and UMTS. For this I looked into both theoretical and practical questions on security in the access part of such technologies. I also proposed improvements to the wireless standards which prevent fake-base station attacks (IMSI catchers).<br/> My current research is mostly focussed on maturing the <a href="https://privacybydesign.foundation/irma/">IRMA (I Reveal My Attributes)</a> technology. The IRMA technology offers a way to authenticate users based on a subset of their attributes, which results in a very flexible and privacy-friendly eco system.