INTER-ISDN FUNDAMENTAL INTERFACE CONNECTION DEVICE

PURPOSE:To transmit an S/Q bit in transparent fashion and to perform start-up and stoppage by taking synchronism between both terminals of a transmission line. CONSTITUTION:This device is provided with transmission equipment A, B connected between a network of ISDN fundamental interface and a terminal, and the transmission equipment A is provided with an S-point interface part 21 and an its own station information multiplex part 23 which multiplexes a D- channel on the S/Q bit or coded start-up/stoppage information out of a 2B+D channel and the S/Q bit or start-up/stoppage information separated by a speed change and channel separation part, and the transmission equipment B is provided with a counter station information separation part 32 which separates the D-channel and the S/Q bit or the start-up/stoppage information multiplexed at the its own station information separation part 23. In this way, the S/Q bit can be transmitted in transparent fashion, and start-up/stoppage procedure can be performed for the start-up/stoppage information by taking synchronism at both terminals of the transmission line.