also from chicago, john tolva, former chief technology officer for the city.e is currently president of the engineering firm positive energy practice which promotes environmentally responsible design. here in washington, d.c., justin brooklyn, director of consumer privacy, thanks to all of you for joining us. charlie, about 50 sensors going up by the end of the year. i mentioned a couple of things, but what data are you most excited about collecting? what will these sensors do that hasn't been done before? >> well, one thing that's different about this project is it's really a platform for sensing and other sorts of services that you might want to try out in a major city at urban scales. the data we are collecting is environmental. i would characterize it not as the city watching people but an opportunity for the people to watch the city. what these will do is publish data in realtime about air quality, light, noise, and things like that. >> so what is it to gain from this data that people who live and work in these areas don't already know? >> well, as we get