SaTC: CORE: Small: Efficient Trustless Distributed Cryptography

Distributed cryptography refers to the paradigm where different parties or organizations jointly run a protocol for privacy or integrity. Prominent examples include secure multi-party computation and distributed ledger technology. A central goal in distributed cryptography is to avoid any centralized trusted party or single point of failure. Many protocols and systems today, however, still need to keep some degree of central trust, often in the form of an initial trusted dealer or trusted setup phase. These central trust assumptions go against the philosophy of distributed cryptography. The reason why they are still common is efficiency and convenience. More often than not, solutions without central trust are harder to construct and more costly than ones using central trust. This project seeks to invent and promote distributed cryptographic protocols without central trust by placing them on equal footing with their trusted counterparts in terms of simplicity and efficiency. The project will study a series of fundamental problems including reliable broadcast, Byzantine fault tolerant consensus (the underlying technology of distributed ledgers), verifiable information dispersal, verifiable secret sharing, and distributed randomness beacons. For each of these problems, the goal is to design new solutions that do not rely on any central trust and can match the efficiency of their trusted counterparts, both in terms of asymptotic complexity and practical performance. The project will also design practical distributed key generation and setup generation protocols to help remove central trust from existing distributed cryptographic protocols. A crucial insight that inspired this project is that underlying all these important problems is a simple yet overlooked problem known as data dissemination. The project will systematically investigate data dissemination and apply it to many areas of distributed cryptography. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.