Efficient (Zero-Knowledge) Interactive Proofs for Lattice-based Protocols via Ring Switching
Jiapeng Zhang (USC)
Monday, May 4 2026, 2-3pm
Abstract:
Lattice-based cryptography is one of the most promising directions for building post-quantum secure systems. Due to the emergence of quantum threats, lattice-based protocols have been extensively studied in recent years.
In this talk, I will present a new approach for constructing interactive proofs for lattice-based protocols. Our technique is based on the sumcheck protocol. A key challenge in applying sumcheck directly is that lattice-based protocols are typically defined over cyclotomic rings, whereas the sumcheck protocol is usually executed over finite fields. To bridge this gap, we introduce a simple yet effective technique called ring switching.
Building on this idea, we present several applications, including lattice-based polynomial commitment schemes, verifiable random functions, and aggregate signatures.
This talk is based on joint work with Mi-Ying Huang, Baiyu Li, Xinyu Mao, Ngoc Khanh Nguyen, George O'Rourke, Louis Tremblay Thibault, and Michael Waters.