OADM is an optical add/drop multiplexer, a type of wavelength division multiplexer.
The explanation of sub-insertion here is the meaning of uploading and downloading.
Uploading means that in the optical signal entering the optical add/drop multiplexer, a new wavelength channel is added and multiplexed into the optical fiber together with other channels.
Downloading means that in the optical signal entering the optical add/drop multiplexer, the channel of one wavelength is removed, and other irrelevant channels pass directly through the optical add/drop multiplexer. Note: The dropped channel is directly transferred to the device for service processing, not the meaning of truncation
OADM can be used in the DWDM solution of multiple sites.
