Just across the pond in Sydney, Australia, one of my earliest jobs was related to the traffic control systems at the Roads and Transit Authority (RTA). I do have the distinct impression that they had wireless communications allowing reprogramming of lights by emergency service vehicles. They also had zero authentication ISDN-based video dialups on major intersections, under-road sensor loops to compile traffic volumes, and had kept a VAX running right through to ~2001 and later. Most of that's probably gone now, but I suppose the wireless traffic manipulation is still about.