Sector 7 of the Capitol was dominated by the Communications Tower, from which Space Traffic Control and Temporal Control monitored and logged every passing vessel in Gallifrey's vicinity. It was also rumoured to be the site of Gallifrey High Command's War Room, together with an extraction chamber — although the existence of such chambers was officially denied. (PROSE: A Brief History of Time Lords)
Commander Hilred of the Chancellery Guard had jurisdiction over the sector. (TV: The Deadly Assassin)