Institute for Quantum Science and Technology, and Department of Electrical & Computer Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
Institute for Quantum Science and Technology, and Department of Physics & Astronomy, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
Sci Rep. 2014 Jun 10;4:5233. doi: 10.1038/srep05233.
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 the database provider 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.
在研究充分的密码学原语 1-of-N 不经意传输中，用户从大小为 N 的数据库中检索单个元素，而数据库不会学习检索到的元素。虽然之前已经表明，针对任意强大的对手，安全实现 1-of-N 不经意传输是不可能的，但最近的研究揭示了一类有趣的基于量子力学的私有查询协议，这些协议在欺骗敏感模型中。具体来说，实际协议不需要保证数据库提供者如果这样做会冒着被检测到的风险，就无法学习到检索到的元素。后者足以激励数据库提供者保持诚实。然而，以前提出的协议都无法应对嘈杂的信道。在这里，我们提出了一种容错的私有查询协议，其中新颖的纠错过程是协议安全性的组成部分。此外，我们还在部署的光纤上演示了该协议的概念验证。
