Paper 2026/1445 Original: eprint.iacr.org/2026/1445 ↗
Sublinear-Communication Layered MPC from HSS
Abstract
The server-aided Secure Multi-Party Computation (MPC) model with dynamic participation, where servers may join or leave during the computation is particularly well-suited for practical, long-running applications. Unfortunately, existing protocols supporting dynamic participation either incur communication costs that scale linearly with the circuit size or rely on the heavy hammer of Fully Homomorphic Encryption (FHE). This contrasts with “classic” MPC protocols, where sublinear communication can be achieved without FHE. Focusing on the Layered MPC framework (introduced by David, Ishai, Konring, Kushilevitz, and Narayanan, CRYPTO 2023), we show that this overhead is not inherent. We construct sublinear-communication Layered MPC protocols while maintaining a minimal number of online servers — only two or three per layer. Our constructions rely on a layered-friendly adaptation of Homomorphic Secret Sharing (HSS), which we formalize as HSS with Layered Resharing.
Metadata
- Available format(s)
PDF- Category
- Cryptographic protocols
- Publication info
- Preprint.
- History
- 2026-09-14: last updated
- 2026-07-15: published
- Short URL
- https://ia.cr/2026/1445
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2026/1445,
author = {Anasuya Acharya and Pierre Meyer and Divya Ravi and Rahul Satish},
title = {Sublinear-Communication Layered MPC from HSS},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/1445},
year = {2026},
url = {https://eprint.iacr.org/2026/1445}
}