The CWDM optical module multiplexes the original multiple signals with different wavelengths into one signal, and then transmits it to the receiving end through a single optical fiber. In other words, the CWDM technology is to use. WDM SFP modules can be divided into XENPAK wavelength division SFP modules, X2 wavelength division SFP modules, GBIC wavelength division optical modules, XFP wavelength division SFP modules, SFP wavelength division SFPl modules, and SFP+ wavelength division SFP modules according to different. WDM module can be divided into XENPAK WDM module, X2 WDM module, GBIC WDM module, XFP WDM module, SFP WDM module, SFP+ WDM module, etc. Thin-film filter and PLC based AWG for multiplexing, a full suite of components for optical amplification use, optomechanical or MEMS-based switches for protection or surveillance application, Tap PD for power monitoring and VOA for. Wavelength division multiplexing (WDM) is a technology for increasing the transmission capacity of optical fiber communications by sending multiple data channels simultaneously through a single fiber, each on a different wavelength of light. The article explains the fundamental principle and its.