arXiv:2303.08865

Asymmetric Quantum Secure Multi-Party Computation With Weak Clients Against Dishonest Majority

Theodoros Kapourniotis, Elham Kashefi, Dominik Leichtle, Luka Music, Ollivier, Harold

Published Mar 15, 2023• 2 citations

Abstract

Secure multi-party computation (SMPC) protocols allow several parties that distrust each other to collectively compute a function on their inputs. In this paper, we introduce a protocol that lifts classical SMPC to quantum SMPC in a composably and statistically secure way, even for a single honest party. Unlike previous quantum SMPC protocols, our proposal only requires very limited quantum resources from all but one party; it suffices that the weak parties, i.e. the clients, are able to prepare single-qubit states in the X-Y plane. The novel quantum SMPC protocol is constructed in a naturally modular way, and relies on a new technique for quantum verification that is of independent interest. This verification technique requires the remote preparation of states only in a single plane of the Bloch sphere. In the course of proving the security of the new verification protocol, we also uncover a fundamental invariance that is inherent to measurement-based quantum computing.

DOI: 10.48550/arxiv.2303.08865

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