Exploiting Lack of Hardware Reciprocity for Sender-Node Authentication at the PHY Layer

TL;DR

This paper introduces a PHY-layer authentication method that leverages hardware non-reciprocity parameters to distinguish legitimate senders from intruders, enhancing security in wireless communication.

Contribution

It presents a novel authentication framework using reciprocity parameters, learned during training, for effective binary hypothesis testing at the receiver node.

Findings

High detection probability of intruders demonstrated

Performance surpasses existing schemes in accuracy

Effective in real-time authentication scenarios

Abstract

This paper proposes to exploit the so-called {\it reciprocity parameters} (modelling non-reciprocal communication hardware) to use them as decision metric for binary hypothesis testing based authentication framework at a receiver node Bob. Specifically, Bob first learns the reciprocity parameters of the legitimate sender Alice via initial training. Then, during the test phase, Bob first obtains a measurement of reciprocity parameters of channel occupier (Alice, or, the intruder Eve). Then, with ground truth and current measurement both in hand, Bob carries out the hypothesis testing to automatically accept (reject) the packets sent by Alice (Eve). For the proposed scheme, we provide its success rate (the detection probability of Eve), and its performance comparison with other schemes.