CWDM (Coarse Wavelength Division Multiplexing) modules use 18 different wavelengths between 1270nm and 1610nm, each with a unique pull ring color for easy identification. This color coding enables fast troubleshooting and port mapping in complex CWDM networks. Every optical transceiver operates at a specific wavelength, typically. Distinguish the wavelength by the color of the pull ring of the optical module In order to distinguish their own optical modules, different manufacturers can distinguish them by their wavelength, transmission distance, packaging, etc. Do you know what other methods can be used to distinguish them?🚀 Understanding SFP Optical Modules – Wavelength & Pull Ring Color Codes When working with networking and fiber optics, SFP (Small Form-Factor Pluggable) modules are crucial for connecting switches, routers, and servers over fiber cables. One of the most effective and widely used methods is through the pull-tab color on transceiver modules. Purple--Wavelength 1490nm:. The pull ring of the optical module adopts the function of using different colors Their main function is to identify the type, wavelength, and function, allowing technicians to quickly determine its type and use case without removing the optical module.