Run the following command to view device board information and identification details of all optical modules: show inventory The output includes the module type, serial number, Cisco-compatible part number, and other details, which are retrieved from the pre-programmed data in the. Run the following command to view device board information and identification details of all optical modules: show inventory The output includes the module type, serial number, Cisco-compatible part number, and other details, which are retrieved from the pre-programmed data in the. When optical modules operate on a switch, it is usually necessary to read the module's internal information to understand its working status—such as connection status and real-time metrics like optical power and temperature. Additionally, identifying module information helps detect coding. When the optical module on an interface is faulty, you can run the display commands to view information about the optical module. Through transceiver monitoring, also known as digital optical monitoring (DOM), you can view diagnostics like transmitted bias current, transmitted power, received power, transceiver temperature, and power supply voltage. See below for a list of devices that support transceiver monitoring. If. Optical module identification and status monitoring are essential daily tasks for network engineers maintaining Cisco switching systems. This guide provides complete, step-by-step CLI commands to view module type, DOM/DDM diagnostic data, vendor details, and compatibility information, fully. DDM (Digital Diagnostics Monitoring) is a feature that is included in optical modules, such as SFP, SFP+, QSFP, and QSFP+ transceivers.