When to Use Wireless Challenge-Response Physical Layer Authentication: Design of a Measurable Guideline for OFDM

2026-05-07

AI Summary

This work addresses the vulnerability of physical-layer authentication (PLA) in OFDM systems arising from insufficient randomness in wireless channels. To this end, it introduces the first maximum differential likelihood generator (MDLG) attack model, which exposes the security threat posed by subcarrier response correlations to PLA. Furthermore, the study establishes the first quantifiable criterion for assessing PLA applicability by integrating NIST randomness tests with channel response analysis, enabling effective evaluation of real-world channel security. Experimental results validate the feasibility of the proposed MDLG attack and demonstrate that the developed criterion significantly enhances PLA robustness in practical wireless environments.

Abstract

The security of wireless challenge-response Physical Layer Authentication (PLA) based on Orthogonal Frequency Division Multiplexing (OFDM) relies on a sufficiently random fading channel condition, which is commonly assumed in existing studies. However, in practical scenarios, such a condition is not always guaranteed and the responses of OFDM subchannels may exhibit correlation.} Consequently, ensuring the security of such PLA systems remains an unsolved problem. In this paper, we propose a novel adversary model, called Maximum Differential Likelihood Generator (MDLG), which exploits the weak correlation property in practical wireless channel to launch effective attacks against PLA. Based on this model, we create a measurable guideline using randomness testing to decide when we can in fact use PLA in a practical wireless channel condition. Extensive real-world experiments validate the effectiveness of the MDLG attack and demonstrate how the proposed guideline can help protect the security of PLA.

Problem

• Physical Layer Authentication
• OFDM
• wireless channel correlation
• security
• randomness

Innovation

• Physical Layer Authentication
• OFDM
• MDLG attack
• randomness testing
• wireless security