Journal Article

Feasible attack on detector-device-independent quantum key distribution

Ma, Haiqiang, Xiao, Jinghua, Liu, Hongwei, Wei, Kejin, Sun, Yongmei, Ji, Yuefeng, Yang, Xiuqing, Zhang, Yong

2017

Overview

Recently, to bridge the gap between security of Measurement-device-independent quantum key distribution (MDI-QKD) and a high key rate, a novel protocol, the so-called detector-device-independent QKD (DDI-QKD), has been independently proposed by several groups and has attracted great interest. A higher key rate is obtained, since a single photon bell state measurement (BSM) setup is applied to DDI-QKD. Subsequently, Qi has proposed two attacks for this protocol. However, the first attack, in which Bob’s BSM setup is assumed to be completely a “black box”, is easily prevented by using some additional monitoring devices or by specifically characterizing the BSM. The second attack, which combines the blinding attack and the detector wavelength-dependent efficiency, is not explicitly discussed, and its feasibility is not experimentally confirmed. Here, we show that the second attack is not technically viable because of an intrinsically wavelength-dependent property of a realistic beam splitter, which is an essential component in DDI-QKD. Moreover, we propose a feasible attack that combines a well-known attack—detector blinding attack with intrinsic imperfections of single-photon detectors. The experimental measurement and proof-of-principle test results confirm that our attack can allow Eve to get a copy of quantum keys without being detected and that it is feasible with current technology.

• Publisher: Nature Publishing Group UK,Nature Portfolio
• Subject: 639/766/483/3925 / 639/766/483/481 / Humanities and Social Sciences / multidisciplinary / Science / Science (multidisciplinary)