This talk addresses in the main the problem of secure control of networked cyber-physical systems, and, title notwithstanding, a digression into mm-wave networks that have quickly become of great topical interest since the FCC release of 10.85 GHz of spectrum in July 2016. We consider physical plants controlled by multiple actuators and sensors communicating over a network, where some sensors and actuators could be ``malicious." A malicious sensor may not report the measurement that it observes truthfully, while a malicious actuator may not apply actuation signals in accordance with the designed control policy. In the first segment of the talk, we introduce the notions of securable and unsecurable subspaces of a linear dynamical system, which have important operational meanings in the context of secure control. These subspaces may be regarded as analogs of the controllable and unobservable subspaces reexamined in an era where there is intense interest in cybersecurity of control systems. In the second segment of the talk, we address the problem of detecting malicious sensors in a system. We propose a general technique, called ``Dynamic Watermarking,'' by which honest actuators in the system can detect the actions of malicious sensors, and disable closed-loop control based on their information. We then digress to Medium Access Control (MAC) design for mm-wave wireless networks. The high directionality of mm-wave nodes introduces the problem of deafness, which renders conventional MAC protocols such as CSMA/CA ineffective in orchestrating the medium access. We outline some preliminary results on TrackMAC, a MAC protocol designed for mm-wave wireless networks, and show how it achieves efficient medium access. This talk is based on several joint works with Prof. P. R. Kumar, Woo-Hyun Ko, and Simon Yau of Texas A&M University, and Dr. Amal Ekbal, Dr. Ahsan Aziz, and Dr. Nikhil Kundargi of National Instruments.
Bharadwaj Satchidanandan is a fourth-year graduate student in the Electrical and Computer Engineering department at Texas A&M University, where he is advised by Prof. P. R. Kumar. Prior to this, he obtained his master's degree in Electrical Engineering from Indian Institute of Technology Madras, where he was advised by Prof. David Koilpillai and Prof. Kiran Kuchi. Between May 2015 and August 2015, he interned at Intel Labs, Santa Clara, CA, where he worked on interference cancellation algorithms for next-generation wireless networks. Between June 2017 and August 2017, he interned at National Instruments, Austin, TX, where he worked on medium access control for mm-wave wireless networks. His research interests lie in the areas of cyber-physical systems, power systems, security, database privacy, communications, control, and signal processing. In addition to technical publications, his research has also garnered significant media coverage, notably in ACM TechNews, TechRepublic, Texas A&M Today, Texas A&M Engineer, and the top story of 6PM news in KBTX TV. He was the recipient of the Best Student Paper Award at the 9th International Conference on Communication Systems and Networks (COMSNETS). He was also the winner of the global Hackathon contest conducted as a part of the 2017 Global Conference on Cyber Space (GCCS 2017), for which he received an award from the Prime Minister of India.