I am an Associate Professor at the Johns Hopkins Information Security Institute. My research includes techniques for privacy-enhanced information storage, anonymous payment systems, and bilinear map-based cryptography. I am one of the creators of the Zerocash protocol, which is used by the Zcash cryptocurrency, and a founder of an encryption startup Zeutro. I was formerly a partner in Independent Security Evaluators, a custom security evaluation and design consultancy and I currently consult independently. From 1999-2003, I served as a senior technical staff member at AT&T Laboratories/Research in Florham Park, NJ.