Previous and Ongoing Work

Broadly speaking, my research interests lie at the intersection of the computer security, privacy, and distributed systems disciplines. In particular, I am interested in systems that facilitate secure interactions across multiple security domains while still preserving each individual’s privacy and autonomy. For my dissertation, I have focused mainly on the systems challenges surrounding the adoption of trust negotiation and other distributed proof approaches to authorization in open computing systems. In these approaches, resources are protected by attribute-based access policies, rather than explicit access control lists. Entities use cryptographic credentials issued by third-party attribute certifiers (e.g., professional organizations, employers, or government bodies) to prove various attributes about themselves and their surrounding environment. Since these attributes might be considered sensitive, they can optionally be protected by release policies placing constraints on the individuals to whom they can be disclosed. As a result, trust negotiation sessions are bilateral and iterative exchanges of policies and credentials capable of developing new trust relationships on-the-fly. My research has addressed gaps between the theoretical models used to reason about trust negotiation protocols and real-life asynchronous distributed systems, and has led to the development of provably-correct and highly-efficient implementations of trust negotiation system components.