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arXiv · 2412.10290

Evaluation of quantum key distribution systems against injection-locking attacks

Jerome Wiesemann·Fadri Grünenfelder·Ana Blázquez·Nino Walenta·Davide Rusca
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Abstract

While ideal quantum key distribution (QKD) systems are well-understood, practical implementations face various vulnerabilities, such as side-channel attacks resulting from device imperfections. Current security proofs for decoy-state BB84 protocols either assume uniform phase randomization of Alice's signals, which is compromised by practical limitations and attacks like injection locking, or rely on a (partially) characterized phase distribution. This work presents an experimental method to characterize the phase de-randomization from injection locking using a heterodyne detection setup, providing a lower bound on the degree of isolation required to protect QKD transmitters against injection-locking attacks. The methods presented are source-agnostic and can be used to evaluate general QKD systems against injection-locking attacks.

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Jerome Wiesemann, Fadri Grünenfelder, Ana Blázquez, Nino Walenta, Davide Rusca. 2024-12-13. Evaluation of quantum key distribution systems against injection-locking attacks. https://doi.org/10.1063/5.0260685

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