1/5 RESEARCH STATEMENT

Overview. My research area is cryptography, with a practice-oriented theme. The cryptography community has, because of historical reasons, evolved to two largely disconnected groups. The the-ory side targets provable security, offering aesthetically pleasing, rigorously secure results with good asymptotic efficiency. But those products usually have no customers, because their concrete running time is slow, their implementations difficult, and most importantly, the problems they solve often not of genuine interest to practitioners. In practice, developers are willing to use heuristics to achieve good performance and reduce engineering effort. My research thus aims to bridge the gap between the theory and practice of cryptography: I’m interested in delivering products of real utility that are theoretically justified, easy to implement, and even significantly faster than heuristic solutions. My research papers have embodied what I call a model-centric approach. A cryptographic model defines what an adversary is allowed to do for its attacks, and when it successfully breaks the scheme. My thesis is that good modeling will provide clean abstraction boundaries for ease of correct use, and eventually lead to performance improvements. “A problem well-stated is a problem half-solved”, as the adage goes. I stress that getting clean models is only the first step; there is still a big gap towards obtaining good solutions. After one nails down the definitional treatment, one has to use it as a springboard to get new schemes, tighten security analyses, and rev up performance. But the springboard has to come first. Recognition. The material in my doctoral dissertation [5, 6, 7], in which I established a foundation for a 30-year-old central technique in secure distributed computing, has been used in cryptograph