... ADM, it can be inserted in STM-4 ring or a line which provide 4×STM-1 optical tributaries;2.As a terminal ... , it can multiplex 4×STM-1 to a STM-4 line port;3.ZS-OS622MI can also be used ... , compactness, high reliability, low power consumption;Provides 2×STM-4 optical line ports, which can realize independent service-assignment or 1+1 ...