Intheseimages, buildingsandpaved areas appear in shades ofgrayorbeige, the clearestexample being the McCarranInternationalAirport near the bottom center of each image.
Very few, such as McCarranInternational in Las Vegas, monitor all wireless traffic for intruders. (The Vegas airport officials are quick to add that they don't censor for content.) Others, like San Francisco International, are laissez-faire.