The ITU grid labels DWDM channels with a letter 'band' and a
numeric channel. Within this mib, the band is indicated by
this object, and the channel number is shown in the object
nbsOsaChannelNumber.
Frequencies of at least 180100 GHz but less than 190100 GHz
are considered the L spectrum, and frequencies of at least
190100 but less than 200100 GHz are considered the C spectrum.
Frequencies evenly divisible by 100 GHz are designated with
a 'C' or 'L' prepended to the channel number. Frequencies
that are offset by 50 GHz are designated 'H' within the C
spectrum, and 'Q' within the L spectrum.