A channel perceiving attack and the countermeasure on long-range IoT physical layer key generation



Yang, Lu, Gao, Yansong, Zhang, Junqing ORCID: 0000-0002-3502-2926, Camtepe, Seyit and Jayalath, Dhammika
(2022) A channel perceiving attack and the countermeasure on long-range IoT physical layer key generation. COMPUTER COMMUNICATIONS, 191. pp. 108-118.

[img] Text
A channel perceiving attack and the countermeasure on long-range IoT physical layer key generation.pdf - Author Accepted Manuscript

Download (4MB) | Preview

Abstract

Physical layer key generation is a lightweight technique to generate secret keys from wireless channels for resource-constrained Internet of things (IoT) applications. The security of the key generation relies on spatial decorrelation, which assumes that eavesdroppers observe uncorrelated channel measurements when they are located over a half-wavelength away from legitimate users. Unfortunately, no experimental validation exists for communications environments with both large-scale and small-scale fading effects. Furthermore, while the current key generation work mainly focuses on short-range communications techniques such as WiFi and ZigBee, the exploration with long-range communications, e.g., LoRa, is somewhat limited. This paper presents a long-range key generation testbed and reveals a new attack scenario that perceives and utilizes large-scale fading effects in key generation channels, by using multiple eavesdroppers circularly around a legitimate user. We formalized such an attack and validated it through extensive experiments conducted in indoor and outdoor environments. It is corroborated that the attack reduces secret key capacity when large-scale fading is predominant. We further investigated potential defenses by proposing a conditional entropy and high-pass filter-based countermeasure to estimate and eliminate large-scale fading components. The experimental results demonstrated that the countermeasure significantly improved the key generation's security when both large-scale and small-scale fading existed. The keys generated by legitimate users have a desirable low key disagreement rate (KDR) and are validated by the NIST randomness tests. In contrast, eavesdroppers’ average KDR is increased from 0.25 to 0.49.

Item Type: Article
Uncontrolled Keywords: Large-scale fading, Long-range IoT, Physical layer key generation, Security defense, Secret key capacity
Divisions: Faculty of Science and Engineering > School of Electrical Engineering, Electronics and Computer Science
Depositing User: Symplectic Admin
Date Deposited: 13 May 2022 14:23
Last Modified: 29 Apr 2023 01:30
DOI: 10.1016/j.comcom.2022.04.027
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3154737