Flow control..
I can feel several Capt's special reports comming up about this, hope it helps!
The one and only time I got to visit the shiny new ATC unit in DXB was quite surprizing. Buried away in the bowls of the tower were a bunch of hard working guys and gals staring at antquated out of focus screens that made me want to puke up after just a few minutes. I guess once your eyesight goes it prabably looks OK. The powers that be apparently didn't want to update something that nobody else could see!!!