DES Cybersecurity Project

Revision as of 11:49, June 19, 2021

Cybersecurity Project of the DES Group at the University of Michigan

Resilient Supervisory Control in the Presence of Sensor or Actuator Attacks

For several years, our group has been interested in studying the effect of sensor and actuator attacks in feedback control of cyber-physical systems (CPS). Our focus has been on the higher-level control logic of CPS, i.e., the supervisory control layer, using discrete-event models of the system dynamics. The doctoral dissertation of Rômulo Meira-Góes is devoted to this topic.

We started this line of work with PhD graduate Yi-Chin Wu and Professor Raymond Kwong of the University of Toronto, Canada, and continued with Professor Lilian Kawakami Carvalho of the Federal University of Rio de Janeiro, Brazil. These efforts led to the journal paper below, where we considered different scenarios of compromised sensors and/or actuators at the supervisory control layer of feedback control loops:

• L. K. Carvalho, Y.-C. Wu, R. Kwong, and S. Lafortune, "Detection and Mitigation of Classes of Attacks on Supervisory Control Systemss," Automatica, Vol. 97, pp. 121-133, November 2018.

Rômulo Meira-Góes then joined our efforts as a doctoral student. So did new collaborator Professor Eunsuk Kang of CMU, USA. We focused on sensor deception attacks and examined first the synthesis problem from the viewpoint of the attacker, using both logical and stochastic models, in the papers:

• R. Meira-Góes, E. Kang, R. Kwong, and S. Lafortune, "Synthesis of Sensor Deception Attacks at the Supervisory Layer of Cyber-Physical Systems," Automatica, Vol. 121, Article 109172, November 2020.

• R. Meira Góes, R. Kwong, and S. Lafortune, "Synthesis of optimal multi-objective attack strategies for controlled systems modeled by probabilistic automata," IEEE Transactions on Automatic Control. In print.

We also looked at exploiting a notion of abstraction to make the synthesis of attacks more tractable, with collaborator Professor Sahar Mohajerani of Chalmers University, Sweden:

• S. Mohajerani, R. Meira-Góes, and S. Lafortune, "Efficient Synthesis of Sensor Deception Attacks Using Observation Equivalence-Based Abstraction," Proceedings of the 15th International Workshop on Discrete Event Systems, November 2020, pp. 28-34.

We then turned our attention to various defense mechanisms against sensor deception attacks, resulting in the following papers, many written in collaboration with Dr. Hervé Marchand of IRISA:

• R. Meira-Góes, H. Marchand, and S. Lafortune, "Synthesis of Supervisors Robust Against Sensor Deception Attacks," IEEE Transactions on Automatic Control. In print.

• R. Meira-Góes, H. Marchand, and S. Lafortune, "Towards Resilient Supervisors against Sensor Deception Attacks," Proceedings of the 58th IEEE Conference on Decision and Control, December 2019, pp. 5144-5149.

• R. Meira-Góes and S. Lafortune, "Moving Target Defense based on Switched Supervisory Control: A New Technique for Mitigating Sensor Deception Attacks," Proceedings of the 15th International Workshop on Discrete Event Systems, November 2020, pp. 317-323.

Along with Dr. Christoforos Keroglou (then with KTH, Sweden), we considered the detection of attacks in the paper:

• R. Meira-Góes, C. Keroglou, and S. Lafortune, "Towards probabilistic intrusion detection in supervisory control of discrete event systems," Proceedings of the 21st IFAC World Congress, July 2020, pp. 1776-1782.

Another line of investigation is the case of communication/computer protocols subject to person-in-the-middle attacks, which MS student Shoma Matsui considered in the paper:

• S. Matsui and S. Lafortune, "Synthesis of Winning Attacks on Communication Protocols using Supervisory Control Theory, February 2021.

Financial acknowledgement: We acknowledge in the papers above the sponsors that have made this work possible, principally the US National Science Foundation.

We welcome your comments.