... supports 3 mode: local clock, adaptive and loopback•Provide 2 STM-1 optical ports , Support 1 + 1 protection•Ethernet built ... 48 V dual power supply, realize 1 + 1 backupSpecification:Capacity2 STM-1 optical port (1+1 protection), 5GE electronically port , ... and 1 external clock portSTM-1 portTransmission rate: 155520kbit/s ±4.6ppmLine code : scramble NRZOptical wavelength : standard 1310NM, optional / ...