Inside the bitter campus privacy battle over smart building sensors
The hall’s futuristic features included carbon dioxide sensors that automatically pipe in fresh air, a rain garden, a yard for robots and drones, and experimental super-sensing devices called Mites. Mounted in more than 300 locations throughout the building, these light-switch-size devices can measure 12 types of data—including motion and sound. Mites were embedded on the walls and ceilings of hallways, in conference rooms, and in private offices, all as part of a research project on smart buildings led by CMU professor Yuvraj Agarwal and PhD student Sudershan Boovaraghavan and including another professor, Chris Harrison.
“The overall goal of this project,” Agarwal explained at an April 2021 town hall meeting for students and faculty, is to “build a safe, secure, and easy-to-use IoT [Internet of Things] infrastructure,” referring to a network of sensor-equipped physical objects like smart light bulbs, thermostats, and TVs that can connect to the internet and share information wirelessly.
Not everyone was pleased to find the building full of Mites. Some in the department felt that the project violated their privacy rather than protected it. In particular, students and faculty whose research focused more on the social impacts of technology felt that the device’s microphone, infrared sensor, thermometer, and six other sensors, which together could at least sense when a space was occupied, would subject them to experimental surveillance without their consent.
“It’s not okay to install these by default,” says David Widder, a final-year PhD candidate in software engineering, who became one of the department’s most vocal voices against Mites. “I don’t want to live in a world where one’s employer installing networked sensors in your office without asking you first is a model for other organizations to follow.”
All technology users face similar questions about how and where to draw a personal line when it comes to privacy. But outside of our own homes (and sometimes within them), we increasingly lack autonomy over these decisions. Instead, our privacy is determined by the choices of the people around us. Walking into a friend’s house, a retail store, or just down a public street leaves us open to many different types of surveillance over which we have little control.
Against a backdrop of skyrocketing workplace surveillance, prolific data collection, increasing cybersecurity risks, rising concerns about privacy and smart technologies, and fraught power dynamics around free speech in academic institutions, Mites became a lightning rod within the Institute for Software Research.
Voices on both sides of the issue were aware that the Mites project could have an impact far beyond TCS Hall. After all, Carnegie Mellon is a top-tier research university in science, technology, and engineering, and how it handles this research may influence how sensors will be deployed elsewhere. “When we do something, companies … [and] other universities listen,” says Widder.
Indeed, the Mites researchers hoped that the process they’d gone through “could actually be a blueprint for smaller universities” looking to do similar research, says Agarwal, an associate professor in computer science who has been developing and testing machine learning for IoT devices for a decade.
