Efficient Three-party Computation: An Information-theoretic Approach from Cut-and-Choose

TL;DR

This paper introduces an information-theoretic three-party computation protocol using cut-and-choose, achieving malicious security with reduced communication rounds and comparable computational cost to semi-honest protocols.

Contribution

It adapts the cut-and-choose technique to information-theoretic secure 3PC, providing malicious security with fewer communication rounds.

Findings

Achieves malicious security with cheating probability $2^{-s}$

Reduces communication rounds compared to existing protocols

Maintains computational efficiency close to semi-honest protocols

Abstract

As far as we know, the literature on secure computation from cut-and-choose has focused on achieving computational security against malicious adversaries. It is unclear whether the idea of cut-and-choose can be adapted to secure computation with information-theoretic security. In this work we explore the possibility of using cut-and-choose in information theoretic setting for secure three-party computation (3PC). Previous work on 3PC has mainly focus on the semi-honest case, and is motivated by the observation that real-word deployments of multi-party computation (MPC) seem to involve few parties. We propose a new protocol for information-theoretically secure 3PC tolerating one malicious party with cheating probability $2^{-s}$ using $s$ runs of circuit computation in the cut-and-choose paradigm. The computational cost of our protocol is essentially only a small constant worse than that of state-of-the-art 3PC protocols against a semi-honest corruption, while its communication round is greatly reduced compared to other maliciously secure 3PC protocols in information-theoretic setting.