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arXiv · 1907.09661

Asymmetric delay attack on an entanglement-based bidirectional clock synchronization protocol

Jianwei Lee·Lijiong Shen·Alessandro Cerè·James Troupe·Antia Lamas-Linares·Christian Kurtsiefer
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Abstract

We demonstrate an attack on a clock synchronization protocol that attempts to detect tampering of the synchronization channel using polarization-entangled photon pairs. The protocol relies on a symmetrical channel, where propagation delays do not depend on propagation direction, for correctly deducing the offset between clocks -- a condition that could be manipulated with optical circulators, which rely on static magnetic fields to break the reciprocity of propagating electromagnetic fields. Despite the polarization transformation induced within a set of circulators, our attack creates an error in time synchronization while successfully evading detection.

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Jianwei Lee, Lijiong Shen, Alessandro Cerè, James Troupe, Antia Lamas-Linares, Christian Kurtsiefer. 2019-07-23. Asymmetric delay attack on an entanglement-based bidirectional clock synchronization protocol. https://doi.org/10.1063/1.5121489

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