For tunable transceivers we might ask why it only works in DWDM systems. This is because the frequency spacing in CWDM systems is too wide compared to the narrow band gaps of DWDM systems. Dense Wavelength Division Multiplexing (DWDM) was originally Refers to the ability (and cost) to multiplex optical signals in the 1550 nm band to take advantage of Erbium-Doped Fiber Amplifiers (EDFAs), which are efficient at wavelengths between approximately 1525-1565 nm (C-band), or 1570–1610 nm ( L-band).

The wavelength conversion transponder was originally used to convert the transmission wavelength of the client layer signal to one of the internal wavelengths of the tunable DWDM in the 1,550 nm band. The wavelength-converting transponders quickly took on the additional function of signal regeneration. Signal regeneration in transponders rapidly evolves through 1R to 2R to 3R to overhead monitoring multi-bit rate 3R regenerators.

About 88 different channels can be set up at 0.4nm intervals, which is the 50 GHz band. These optics typically start with channels 16 to 61, but this depends on the manufacturer of the router/switch and the channels it supports. Adjust the wavelength by changing the filter wavelength. Adjusting these optics can be done by us and some smart networking equipment can do it for you. Transceivers can be used in various types of equipment, such as switches, routers, and servers from different vendors. These transponders are spare batches of a given optical transmission system, and they can replace a faulty fixed wavelength transponder whose frequency is tuned by embedded software and external operating software with a laptop or API application.

Wavelength-tunable optical transceivers are becoming increasingly important as components to enable ROADM functionality in next-generation networks. These transceivers feature the ability to switch their wavelengths between different DWDM channels when used in a network. Channel switching capabilities result in a reduction in component count and cost in today's DWDM systems. "