cronokirby

(2026-04) -mathsf{Veloz}; Efficient and Flexible Distribution Framework for Code-Based Polynomial Commitment Scheme

2026-04-12

Abstract

Polynomial commitment schemes (PCSs) are a fundamental cryptographic primitive that allows a prover to reveal evaluations for a committed polynomial. Motivated by the inefficiency of proof generation for large-scale computations as well as the concerns regarding third-party reliance and quantum threats, a line of recent works has focused on distributing code-based PCS, where the proving workload is distributed among multiple sub-provers to accelerate proof generation, while preserving transparent setup and plausible quantum resilience. However, for MM sub-provers generating an evaluation proof for a polynomial of size NN, existing solutions either require O(N)O(N) total communication among sub-provers, or incur an O(M)O(M) overhead in proof size.

In this paper, we introduce Veloz\mathsf{Veloz}, a novel distribution framework for code-based multilinear PCS, which for the first time achieves communication cost sublinear in NN, and eliminates the dependence of proof size on the number of sub-provers, without compromising proving speed or security. At its core is a customized proof aggregation method from interleaved code that efficiently combines sub-proofs via minimum communication. We further present two instantiations of Veloz\mathsf{Veloz}: one based on Reed-Solomon code, VelozRS\mathsf{Veloz}_{\text{RS}}, achieves O(NM\logN\logN)O(\frac{N}{M}\log{\frac{N}{\log{N}}}) proving time, O(λ\log2N\log\logN+MN\logN)O(\lambda \cdot \frac{\log^{2}{N}}{\log\log{N}} + M\cdot\frac{N}{\log{N}}) communication, and O(λ\log2N\log\logN)O(\lambda \cdot \frac{\log^{2}{N}}{\log\log{N}}) proof size; the other based on the fast linear code from Brakedown (Golovnev et al., CRYPTO 2023), VelozLin\mathsf{Veloz}_{\text{Lin}}, features O(NM)O(\frac{N}{M}) proving time, O(λK+MNK)O(\lambda \cdot K + M\cdot\frac{N}{K}) communication, and O(λK)O(\lambda \cdot K) proof size for K[N3,N]K \in [\sqrt[3]{N}, \sqrt{N}], while enjoying field agnosticity.

We also implement both schemes in Rust and conduct a comprehensive performance evaluation. The experimental results demonstrate their linear scalability with increasing MM. More specifically, for N=230N = 2^{30} and M=8M = 8, VelozRS\mathsf{Veloz}_{\text{RS}} takes 74.8s for proof generation, achieving a 5.18 ×\times speedup compared to running a single prover, while VelozLin\mathsf{Veloz}_{\text{Lin}} generates a proof in 26.9s and achieves a 7.02 ×\times speedup.