Hello Matt. These are logical questions. All Blackmagic CCU electronics is built into ATEM switchers. The Camera Control Panel as well as software and "some" third party controllers are connected via Ethernet to the ATEM switcher. Some third party controllers are based upon our Shield for Arduino which is also capable of camera control. To use the ATEM Camera Control Panel, you will need an ATEM. The least expensive ATEM is the Television Studio HD which will control up to 8 cameras. You do not need to use the ATEM for video switching but it is necessary for camera control. Also the Camera Control Panel is designed to switch the Auxiliary output of the ATEM for the camera control person to view on a monitor and scopes. Hope that helps.
Regards, Gary