To assert their legitimacy, French kings were borne under witness, and awoke, bathed, and dressed in public. America's Congress implemented a Freedom of Information Act to create methods for citizens to audit their government. These examples show how traditionally, organizations establish their legitimacy through protocols for disclosure. But disclosure has its practical limits; even organizations need a modicum of privacy. This project aims to balance the needs for both legitimacy and privacy by replacing disclosure protocols by more nuanced cryptographic ones. Although well-studied cryptographic protocols can help achieve this goal, several key challenges must be addressed. As a conceptual challenge, this project studies how the use of cryptographic protocols may inadvertently introduce ways for individuals to cheat by colluding. The eventual goal is to eliminate this phenomena. As an implementation challenge. this project proposes a principled way to transform high-level specifications of special cryptographic protocols into implementations. Finally, as an efficiency challenge, this project studies a promising ``optimistic rational'' method for protocol design that can dramatically reduce communication complexity. In summary, this project studies methods organizations can use to establish their legitimacy by analyzing new models, new ways of organizing communication, and new methods for implementation. To disseminate these ideas, this project's educational activities include course development, outreach to high school teachers so that ideas from cryptography can be woven into their lessons, direct interaction with high school students, development of privacy tools, and mentoring.
CAREER: Legitimacy through Cryptography