Wiktionary
switchroom
n. (context telecommunications English) A room, often an entire floor, containing switching equipment, especially for telephone lines.
Usage examples of "switchroom".
They moved through a switchroom annex behind the control room and went outside via a door at the far end, where they could talk away from unwelcome ears.
One of the guards had come through into the switchroom to keep an eye on them, but he was staying back at the far end.