> That´s not my problem to solve, but think about it: You can get a lot more > information using CCTV cameras, and those are everywhere. Unfortunately, > nobody cares, and it´s not like you have a choice. So why would there > be any legal issues? It's called "A Law". Different places have different laws. Different places have different attitudes towards being lawful. > > I´m surprised that wireless access point controllers, by default, do not > use the strength of the signal received from a device by three or more access > points to simply triangulate the position of the device. Of course, you > only get the positions of devices relative to access points, but once you > have that, you only need to use a map of the place that shows all the access > points and the positions of devices relative to them to figure out where > everyone is. I'm surprised you didn't find anything about this on Google - you did try Google didn't you? http://bfy.tw/GtiP top hit https://www.accuware.com/ or this paper https://www.technologyreview.com/s/542561/wi-fi-trick-gives-devices-super-accurate-indoor-location-fixes/ OK. I know I said before it was basically impossible - but I hadn't googled for it then. It just goes to show that asking CentOS admins about cutting edge WiFi issues is not going to get you very far. P.