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arXiv · 2511.10847

A New Quantum Secure Time Transfer System

Ravi Singh Adhikari·Aman Gupta·Anju Rani·Xiaoyu Ai·Robert Malaney
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Abstract

High-precision clock synchronization is essential for a wide range of network-distributed applications. In the quantum space, these applications include communication, sensing, and positioning. However, current synchronization techniques are vulnerable to attacks, such as intercept-resend attacks, spoofing, and delay attacks. Here, we propose and experimentally demonstrate a new quantum secure time transfer (QSTT) system, subsequently used for clock synchronization, that largely negates such attacks. Novel to our system is the optimal use of self-generated quantum keys within the QSTT to information-theoretically secure the maximum amount of timing data; as well as the introduction, within a hybrid quantum/post-quantum architecture, of an information-theoretic secure obfuscated encryption sequence of the remaining timing data. With these enhancements, we argue that our new system represents the most robust implementation of QSTT to date.

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Ravi Singh Adhikari, Aman Gupta, Anju Rani, Xiaoyu Ai, Robert Malaney. 2025-11-13. A New Quantum Secure Time Transfer System. https://arxiv.org/abs/2511.10847

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