# Dynamic watermarking for general LTI systems

@article{Hespanhol2017DynamicWF, title={Dynamic watermarking for general LTI systems}, author={Pedro Hespanhol and Matthew Porter and Ram Vasudevan and Anil Aswani}, journal={2017 IEEE 56th Annual Conference on Decision and Control (CDC)}, year={2017}, pages={1834-1839} }

Detecting attacks in control systems is an important aspect of designing secure and resilient control systems. Recently, a dynamic watermarking approach was proposed for detecting malicious sensor attacks for SISO LTI systems with partial state observations and MIMO LTI systems with a full rank input matrix and full state observations; however, these previous approaches cannot be applied to general LTI systems that are MIMO and have partial state observations. This paper designs a dynamic…

## 20 Citations

### Statistical Watermarking for Networked Control Systems

- Mathematics, Computer Science2018 Annual American Control Conference (ACC)
- 2018

A statistical watermarking test that can detect both sensor and communication attacks in closed-loop LTI systems with subcontrollers is derived and two approaches to design such a controller using Heymann's lemma and a multi-input generalization of Heymann' lemma are provided.

### Detecting Generalized Replay Attacks via Time-Varying Dynamic Watermarking

- Computer Science, MathematicsIEEE Transactions on Automatic Control
- 2021

This article develops a linear time-varying (LTV) extension to previous dynamic watermarking methods by designing a matrix normalization factor to accommodate the temporal changes in the system.

### Sensor Switching Control Under Attacks Detectable by Finite Sample Dynamic Watermarking Tests

- Computer Science, MathematicsIEEE Transactions on Automatic Control
- 2021

New finite sample hypothesis tests for dynamic watermarking in the case of bounded disturbances are developed, using the modern theory of concentration of measure for random matrices to overcome the problem of switching between two sets of sensors.

### Secure Control of Networked Control Systems Using Dynamic Watermarking

- Computer ScienceIEEE Transactions on Cybernetics
- 2022

The secure control of networked control systems developing a new dynamic watermarking (DW) scheme is investigated, and theoretical analysis shows that the system performance can be recovered from FDIA using the proposed scheme.

### Detecting Deception Attacks on Autonomous Vehicles via Linear Time-Varying Dynamic Watermarking

- Computer Science2020 IEEE Conference on Control Technology and Applications (CCTA)
- 2020

A replay attack, which replays previously recorded measurements, is shown to be detectable using LTV Dynamic Watermarking in a quick and repeatable manner and an auto-correlation normalizing factor is constructed to remove the effects of auto- Correlation.

### Attack Detection for Networked Control Systems Using Event-Triggered Dynamic Watermarking

- Computer ScienceIEEE Transactions on Industrial Informatics
- 2023

A new event-triggered dynamicWatermarking (ETDW) scheme is designed by treating watermarking as symmetric key encryption, based on the limit convergence theorem in probability, which demonstrates the validity of this proposed scheme.

### Covariance-Robust Dynamic Watermarking

- Computer Science2020 59th IEEE Conference on Decision and Control (CDC)
- 2020

A new dynamic watermarking method is developed that is able to handle uncertainties in the covariance of measurement noise, and it is shown that the efficacy of the tests are exhibited on empirical examples chosen to reflect values observed in a standard simulation model of autonomous vehicles.

### On the Design of Security-Guaranteeing Dynamic Watermarks

- Computer ScienceIEEE Control Systems Letters
- 2020

This letter addresses the problem of designing watermarks for linear systems affected by arbitrarily distributed noise and shows how the fundamental security guarantee of DW can fail when the statistics of the watermark are not chosen appropriately taking into account the parameters of the noise process that affects the system.

### Active detection for exposing intelligent attacks in control systems

- Computer Science2017 IEEE Conference on Control Technology and Applications (CCTA)
- 2017

This paper considers approaches for detecting integrity attacks carried out by intelligent and resourceful adversaries in control systems and carefully review two approaches for active detection: physical watermarking at the control input, and a moving target approach for generating system dynamics.

### A Bernoulli-Gaussian physical watermark for detecting integrity attacks in control systems

- Computer Science2017 55th Annual Allerton Conference on Communication, Control, and Computing (Allerton)
- 2017

This paper considers the analysis and design of Gaussian physical watermarks in the presence of packet drops at the control input, and proposes efficiently solvable optimization problems to intelligently select parameters of the Gaussian input and the Bernoulli drop process while addressing security and performance trade-offs.

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