QKD-based quantum private query without a failure probability

TL;DR

This paper introduces a QKD-based quantum private query protocol that guarantees a zero failure probability and always retrieves exactly one item, enhancing stability and privacy compared to previous methods.

Contribution

The proposed protocol ensures a zero failure probability and always retrieves one item, improving stability and privacy in QKD-based quantum private queries.

Findings

Always retrieves one item with zero failure probability

Enhances database privacy by preventing additional secret leaks

Protocol is cheat sensitive for user privacy

Abstract

In this paper, we present a quantum-key-distribution (QKD)-based quantum private query (QPQ) protocol utilizing single-photon signal of multiple optical pulses. It maintains the advantages of the QKD-based QPQ, i.e., easy to implement and loss tolerant. In addition, different from the situations in the previous QKD-based QPQ protocols, in our protocol, the number of the items an honest user will obtain is always one and the failure probability is always zero. This characteristic not only improves the stability (in the sense that, ignoring the noise and the attack, the protocol would always succeed), but also benefits the privacy of the database (since the database will no more reveal additional secrets to the honest users). Furthermore, for the user's privacy, the proposed protocol is cheat sensitive, and for security of the database, we obtain an upper bound for the leaked information of the database in theory.