If the fault is caused by incorrect configuration or networking environment, change the configuration or networking environment. Check whether the optical modules are Huawei-certified ones. If not, contact the. There are multiple ways that optical modules fail in common ways that can interrupt network connectivity. However, during installation and daily operation, various issues may arise. If. 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. As core components in high-speed data networks, optical transceivers enable communication between switches, routers, and servers through fiber optic links.