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MIT's Wi-Fi network knows where users are

Tracking Wi-Fi usage, with permission, gives users and planners unprecedented ways to understand where people are and where they want to be.
Written by ZDNET Editors, Contributor

MIT's SENSEable City Lab tracks Wi-Fi usage on campus in near real-time and that data can be used in most intriguing ways, MIT Technology Review reports. MIT has one of the largest campus Wi-Fi nets with 2,800 access points. The system is run by Carlo Ratti, who is not an IT guy but "a practicing architect who also runs the SENSEable City Laboratory in MIT's Department of Urban Studies and Planning. [He] wants to study how people work in and move through physical spaces on campus. So he maps real-time usage of MIT's Wi-Fi hubs in a project he calls iSpots."

The system records usage in 15-minute incremets, and for users who agree to be tracked by location, the system can place you to within five meters. Usage is pretty much as you'd expect: high during the day, steady until midnight, bottoming out around 6 am. Friday is slower than the rest of the week, activity starts up again Sunday evening. But here's what's really interesting:

"You can make decisions about where you go and what you do based on where other people go and what they do," says Ratti. "You might be able to schedule a meeting in a dynamic way" by locating people and picking a central location.

"In the past, [planners] have relied on interviews or observations interpreted by mathematical models" to understand how people use the built environment, says Dennis Frenchman, professor of urban studies and planning. "With better information, we can test options more easily and design better, more functional places. At another level, sensing patterns of use will facilitate the design of spaces that respond in real time, adapting themselves hourly or daily to new demands or desires." Rooms, for example, might change color and lighting depending on who is inside. Traffic lights could be programmed so that their timing changes according to the locations of commuters' cell phones. In fact, Ratti's lab has tracked cell-phone movement in two European cities to test the feasibility of just such a system.

 Naturally, there are privacy issues, and Ratti is concerned about what giving control over that information to corporations might mean:

The ability to pinpoint people's locations using their Wi-Fi connections or cell phones could prove critical after a natural disaster. But it also raises major privacy concerns -- and questions about who owns location data. Ratti says that big corporations want to retain control of the data they collect. Google, he says, is "giving a free Wi-Fi infrastructure to San Francisco, but they want to be able to develop business models based on how people use it." Ratti wants to develop novel location-based applications but believes that people should control their own location data. After all, sometimes you just want to be off the grid.

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