In telecommunication, a common control is an automatic telephone exchange arrangement in which the control equipment necessary for the establishment of connections is shared by being associated with a given call only during the period required to accomplish the control function for the given call. The first examples deployed on a major scale were the Director telephone system in London and the panel switch in the Bell System. Direct control telephone exchanges became rare in the 1960s, leaving only common control ones.
Note: During the 1980s, common control exchanges became stored program control exchanges, using common-channel signaling in which the channels that are used for signaling, whether frequency bands or time slots, are not used for message traffic.
Famous quotes containing the words common and/or control:
“The object of government in peace and in war is not the glory of rulers or of races, but the happiness of the common man.”
—William, Lord Beveridge (1879–1963)
“America is not so much a nightmare as a non-dream. The American non-dream is precisely a move to wipe the dream out of existence. The dream is a spontaneous happening and therefore dangerous to a control system set up by the non-dreamers.”
—William Burroughs (b. 1914)