
Several other terms describing aspects of add/drop operation are worthy of note.
A full ROADM is one that provides add/drop (de)multiplexing of any arbitrary
combination of wavelengths supported by the system with no maximum, minimum,
or grouping constraints. If a ROADM has access to only a subset of the wavelengths,
or the choice of the first wavelength introduces constraints on other wavelengths to
be dropped, it is called partial ROADM. The drop fraction of a ROADM is the
maximum number of wavelengths that can be simultaneously dropped, divided by
the total number of wavelengths in the WDM signal. (Typically, the analogously
defined add fraction ...