Critical Rounds in Multi-Round Proofs: Proof of Partial Knowledge and Trapdoor Commitments

Thời gian: 14:00 đến 16:00 Ngày 22/05/2026

Địa điểm: C101, VIASM

Speaker: Dung Bui (Sorbonne Université, CNRS, LIP6, Paris, France).

Mode of participation: online

Abstract: Zero-knowledge simulators, initially developed for proving the security of proof systems, turned out to be also useful in constructing advanced protocols from simple three-move interactive proofs. However, in the context of multi-round public-coin protocols, the interfaces of these auxiliary algorithms become more complex, introducing a range of technical challenges that hinder the generalization of these constructions.

We introduce a framework to enhance the usability of zero-knowledge simulators in multi-round argument systems for protocol designs. Critical-round zero-knowledge relies on the ability to perform complete zero-knowledge simulations by knowing the challenge of just one specific round in advance. We show that these notions are satisfied by diverse protocols based on MPC-in-the-Head, interactive oracle proofs, and split-and-fold arguments.

We demonstrate the usefulness of the critical round framework by constructing proofs of partial knowledge (Cramer, Damgård, and Schoenmakers, CRYPTO’94) and trapdoor commitments (Damgård, CRYPTO’89) from critical-round multi-round proofs.

The work will be presented in IACR Eurocrypt 2026 conference.

Article link : https://eprint.iacr.org/2024/1766

Bio: Dung is a postdoctoral researcher at LIP6, Sorbonne Université, France. She completed her PhD at IRIF, Université Paris Cité. Her research interests are cryptography, including secure multiparty computation, zero-knowledge proofs, and post-quantum cryptography:

------------------------

Join Zoom Meeting
https://zoom.us/j/93655865505?pwd=KP8NSYPTCPDDZw8tYviWxMP5Yx9caS.1

Meeting ID: 936 5586 5505

Passcode: 957331