PURPOSE: To establish the transmission line testing system to show whether data transmission is exactly executed in a wide band ISDN or not by providing a test cell inserting/check means and executing on-lined transmission test while operating an asynchronous transfer mode(ATM) exchange.
CONSTITUTION: Corresponding to a command from a central controller 2 of an ATM exchange 1, a test cell inserting/check means 7 inserts a test data to an ATM cell, transmits the test cell inserted the test data through an ATM switch 3 in the ATM exchange 1 and checks the test data of the test cell returned from an ATM layer 5 or a terminal side subscriber terminal adapter 6 between the ATM switch 3 and a synchronous optical network(SONET) type transmission line 4. Therefore, the transmission line test is executed in the on-lined state. Thus, it can be confirmed to which device in a transmission line the transmission is normally executed or not.
YOSHIMURA SHUJI
KAKUMA SATORU
