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arXiv · 1303.0865

Performing private database queries in a real-world environment using a quantum protocol

Philip Chan·Itzel Lucio-Martinez·Xiaofan Mo·Christoph Simon·Wolfgang Tittel
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Abstract

In the well-studied cryptographic primitive 1-out-of-N oblivious transfer, a user retrieves a single element from a database of size N without the database learning which element was retrieved. While it has previously been shown that a secure implementation of 1-out-of-N oblivious transfer is impossible against arbitrarily powerful adversaries, recent research has revealed an interesting class of private query protocols based on quantum mechanics in a cheat sensitive model. Specifically, a practical protocol does not need to guarantee that database cannot learn what element was retrieved if doing so carries the risk of detection. The latter is sufficient motivation to keep a database provider honest. However, none of the previously proposed protocols could cope with noisy channels. Here we present a fault-tolerant private query protocol, in which the novel error correction procedure is integral to the security of the protocol. Furthermore, we present a proof-of-concept demonstration of the protocol over a deployed fibre.

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Philip Chan, Itzel Lucio-Martinez, Xiaofan Mo, Christoph Simon, Wolfgang Tittel. 2013-10-16. Performing private database queries in a real-world environment using a quantum protocol. https://doi.org/10.1038/srep05233

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