Joint Localization-based Node Authentication and Secret Key Generation

Abstract

In this paper, we devise preprocessing schemes to disentangle channel state information (CSI) into predictable and unpredictable components to simultaneously provide two cornerstone security operations. The predictable components are used for node authentication and the unpredictable components for secret key generation (SKG). For the case of SKG, to prevent Eve from exploiting potential spatial, frequency or time correlations with the legitimate users, which would reduce the effective key space through a decrease in the brute force attack size, in this work, we emphasise the need for reducing the spatial correlation (SC) at different transmitter locations. We also study the trade-off between SC and reconciliation in the uplink and the downlink. Furthermore, we discuss the importance of a more robust criterion - independence - over decorrelation between the legitimate users and eavesdroppers. Finally, we propose a metric for quantifying uniqueness in the predictable components for node authentication, using the total variation distance (TVD).