Give it ten years, and that traffic light problem may solve itself.<p>I would not surprise me if we would eventually see every traffic light broadcast its GPS location, cycle pattern, and phase, either using radio or by modulating their light source.<p>That still is risky (hackers could hack the logic in a traffic light), but less risky than relying on one central authority to know what he whole world looks like.<p>Also, I don&#x27;t think it is a good idea, but chances are police officers will have ways to stop self-driving car without giving visual signs.