Abstract: A telecommunication device for receiving and transmitting DS1 level signals that includes a 1/0 digital cross-connect switch, a GR-303 concentrator, and a frame relay aggregator switch in a single integrated device in one housing that fills less than two standard rack units. The device includes both active and standby/backup controller cards that communicate with eight quad framer cards through a bus located in the backplane. The communication through the backplane is via a 8.192 Mbps signal to and from each quad framer card, passed along a bus. The 8.192 Mbps signal is generated by multiplexing the four DS1 (E-1) signals on the quad framer card. The controller card that is active monitors the status of the DS1 channel associated with each framer and stores historical data about the status in spare buffer registers on each framer. Whenever a transition occurs to the standby/backup controller card, that card can obtain the historical status information from the framers to make the transition more seamless.