BulletCT: Towards More Scalable Ring Confidential Transactions With Transparent Setup
Nan Wang
34th USENIX Security Symposium (USENIX Security '25) · Day 2 · Crypto 2: Private Information Retrieval and Computation
This article delves into **BulletCT**, a novel Ring Confidential Transaction (RingCT) scheme presented by Nan Wang, a research scientist at Cesaro Stata 61, during the USENIX Security conference. The talk critically examines existing RingCT proposals, particularly a recent approach from S&P 2023 (referred to as ZGSX23 in the transcript) that integrates an `any-out-of-proof` mechanism. Through rigorous analysis, Wang and their team uncover significant limitations in this `any-out-of-proof` strategy, arguing that **K-out-of-M proofs** offer a more practical and efficient alternative for achieving scalable and anonymous blockchain transactions.
AI review
Solid applied cryptography research that makes a concrete contribution to the RingCT space — a credible critique of the any-out-of-proof approach in ZGSX23, followed by a genuinely novel construction using a K-weight-based K-out-of-M proof and a permutation-constrained tag proof. Not a world-shaking result, but it's real work that advances the field on a problem that actually matters for deployed privacy systems.