TELEPHONE SWITCHING CONTROL ARRANGEMENT

摘要

TELEPHONE SWITCHING CONTROL ARRANGEMENT A communication system which includes a central control, two time-multiplexed switching units each having a control distribution unit associated therewith and a plurality of interface modules each including a selected active control unit. Data words representing subscribergenerated information are conveyed between interface modules by a selected one of the time-multiplexed switching units designated as active. The active time-multiplexed switching unit also conveys control messages between each of the interface modules and the control distribution unit associated with the active time-multiplexed switching unit. However, the time-multiplexed switching unit designated as standby is also used to convey control messages between each of the interface modules and its associated control distribution unit. Each of the control distribution units routes received control messages to the interface modules via its associated time-multiplexed switching unit or to the central control. The central control directs system operation by transmitting and receiving control messages via the time-multiplexed switching units and their associated control distribution units.