Check the diagnostic information, which shows that the received optical power is low, with a threshold of -3 to -23. Once it exceeds the threshold, an alarm will be triggered. Troubleshoot the link, and if the link is normal, replace the optical. The article Digital Diagnostic Function (DDM) For Optical Modules describes that DDM function can be used for real-time monitoring and fault location of the module's working status, in which the optical module's transmitting optical power and receiving optical power are the key parameters for. The diagnostic information of the optical module displays the current transmit and receive optical power values, as well as the default maximum and minimum power values. Even minor deviations—whether too high, too low, or unstable—can impact signal integrity, trigger service alarms, or interrupt traffic on DWDM, OTN, or long-haul optical line systems. Because optical networks. Optical networks rely on precise power balance—too much power can damage receivers or distort signals, while insufficient power can lead to high bit-error rates, degraded OSNR, or even complete link failures. Socket Verification Nominal laser wavelength = 1310 nm.