Abstract: There is provided a digital switch system for connecting a telephone central office with a number of subscriber lines, in which the system includes at least one central office-digital trunk interface switch which allows digital signals to be transmitted between the switch system and the central office, and a number of subscriber line interface switches which allow signals to be transmitted between the switch system and the subscriber lines, in which each of the subscriber line interface switches is connected with at least one subscriber line via at least one digital-to-subscriber line converter, and in which the central office-digital trunk interface switch and the subscriber line interface switches are connected in a ring-shaped structure.