Remote State Estimation with Privacy Against Eavesdroppers

TL;DR

This paper proposes an encoding scheme for remote state estimation that enhances privacy against eavesdroppers by transmitting noise, balancing confidentiality and legitimate user performance without relying on packet acknowledgments.

Contribution

It introduces a novel noise-based encoding scheme that impairs eavesdropper estimation while minimizing impact on legitimate user performance in unreliable networks.

Findings

The scheme effectively degrades eavesdropper's estimation accuracy.

It maintains high estimation quality for legitimate users.

The approach balances privacy and performance trade-offs.

Abstract

We study the problem of remote state estimation in the presence of a passive eavesdropper, under the challenging network environment of no packet receipt acknowledgments. A remote legitimate user estimates the state of a linear plant from the state information received from a sensor via an insecure and unreliable network. The transmission from the sensor may be intercepted by the eavesdropper. To maintain state confidentiality, we propose an encoding scheme. Our scheme transmits noise based on a pseudo-random indicator, pre-arranged at the legitimate user and sensor. The transmission of noise harms the eavesdropper's performance, more than that of the legitimate user. Using the proposed encoding scheme, we impair the eavesdropper's expected estimation performance, whilst minimising expected performance degradation at the legitimate user. We explore the trade-off between state confidentiality and legitimate user performance degradation.