Couldn't the traffic be LAN? Everyone keeps mentioning 'over the internet' - the device they're doing the editing on could be in a different room in the same building over gigabit++ speeds.
The reason is to never allow anyone (even the editors) to have actual access to the show's files/images. Remote software can prohibit copy/paste, file transfers, and screenshots. I worked in a post facility with 100s of people all remoting in to a server rack down the hall.
