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Virtual Wiretap Channel Based on Wireless Two-way Interferometry

Nobuyasu Shiga, Satoshi Yasuda, Kouki Yonaga, Kenichi Takizawa, Maki Yoshida

Published Dec 4, 2022• 1 citation

Abstract

The wiretap channel is a setting where one aims to obtain information-theoretic security of communicated data under the sole assumption that the channel from a sender Alice to an eavesdropper Eve is “noisier” than that from Alice to a receiver Bob. However, in practice, the difference between the two channels in terms of noise may be much smaller because of the wide spread application of high-performance communication technologies. Thus, establishing a wiretap channel over real channels is a challenging task. In this paper, we report a wiretap channel in the form of a “protocol” (a so-called virtual wiretap channel) realized by using a highly precise wireless clock-synchronization technology called the wireless two-way interferometry (abbreviated as Wi-Wi). Wi-Wi technology has already been implemented in wireless communication devices, and it measures the clock time difference and signal propagation time in a situation where the precisions of both values are mutually affected. That is, Alice or Bob can induce a noise on Eve's clock time difference measurement by physically introducing noise in the signal propagation time between Alice and Bob. We analyzed the proposed wiretap channel referred to as the Wi-Wi wiretap channel experimentally, and estimated its parameters (e.g., the error probabilities). We confirmed that the Wi-Wi wiretap channel works well as a virtual wiretap channel by simulating and experimentally demonstrating a well-known, provably secure, optimal wiretap code over it. The results show that Wi-Wi wiretap channel can serve as a physical layer security, useful for synchronized Internet of Things (IoT) devises.

DOI: 10.1109/globecom48099.2022.10000896

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