10:45 AM - 11:00 AM
▲ [18a-438-5] Monitoring coincident click in DQPS-QKD to prevent side-channel attacks manipulating single-photon detectors
Keywords:DQPS-QKD, Side-channel attack, quantum cryptography
Side-channel attacks manipulating single-photon detector (SPD) have known to be loopholes for realistic quantum key distribution (QKD) systems [1], and measurement-device-independent (MDI) QKD schemes have been proposed and studied to avoid those loopholes [2]. Though some experiments were reported, MDI-QKD is not easy to implement in practice because it requires some synchronization between signals sent from distant two parties. Another countermeasure was also proposed and demonstrated [3], but it needs additional SPDs. Thereupon, this paper proposes a countermeasure against side-channel attacks, without changing the system configuration of a conventional QKD protocol: i.e., differential-quadrature-phase-shift (DQPS) QKD. Side-channel attacks can be found with no additional apparatus by our scheme