n a traditional WDM system, to change a fixed signal transmission path, maintenance personnel have to visit the site to install related hardware and connect optical fibers, which are time- and labor-consuming. The OTN network uses electrical-layer grooming and optical-layer grooming to address these issues. With the help of the two grooming technologies, maintenance personnel can remotely adjust the transmission paths of signals from the control center.
How do electrical-layer grooming and optical-layer groomingwork respectively?
Grooms electrical signals at a granularity of ODUk(k =1, 2(e), 3, 4, or flex)
Grooms optical signals at a granularity of wavelength (λ) by flexibly selecting transmission paths.