Experimental Secure Multiparty Computation from Quantum Oblivious Transfer with Bit Commitment

TL;DR

This paper demonstrates an experimental implementation of a quantum-secure oblivious transfer protocol that enables privacy-preserving secure multiparty computation, with practical application in private set intersection between banks, surpassing previous models.

Contribution

It presents the first practical quantum oblivious transfer protocol using quantum key distribution and bit commitment, enabling real-world secure multiparty computations.

Findings

Successfully implemented quantum oblivious transfer in a real system

Applied QOT to private set intersection between banks

Demonstrated practical feasibility of quantum secure multiparty computation

Abstract

Secure multiparty computation enables collaborative computations across multiple users while preserving individual privacy, which has a wide range of applications in finance, machine learning and healthcare. Secure multiparty computation can be realized using oblivious transfer as a primitive function. In this paper, we present an experimental implementation of a quantum-secure quantum oblivious transfer (QOT) protocol using an adapted quantum key distribution system combined with a bit commitment scheme, surpassing previous approaches only secure in the noisy storage model. We demonstrate the first practical application of the QOT protocol by solving the private set intersection, a prime example of secure multiparty computation, where two parties aim to find common elements in their datasets without revealing any other information. In our experiments, two banks can identify common suspicious accounts without disclosing any other data. This not only proves the experimental functionality of QOT, but also showcases its real-world commercial applications.