This type of stuff was common place with lineal editing systems and has gradually faded off the scene since Non-Linear Editing (on a computer) has taken over.
As mentioned firewire carries camera commands in a similar way as the older LANC system. I have a museum full of it.:-)
A/B/C/D roll, titling, audio and vision mixing can all be done on a computer better and easer and with a stack less cables.
Lanc also controlled zoomoing, tripod heads etc.
Do you actually have a special need other than simple camera control?
Al