A switchless optical add/drop module (OADM) includes: a first variable
optical splitter (VOS) for splitting a composite optical signal including
a plurality of channels into a first portion and a second portion; a
first multi-channel variable optical attenuator (MCVOA) optically coupled
to the first VOS, where the first MCVOA blocks dropped channels of the
first portion, transmits express channels of the first portion, and
balances power levels of each of the transmitted express channels of the
first portion; a second VOS optically coupled to the first MCVOA opposite
to the first VOS for combining the transmitted express channels of the
first portion and added channels; and a second MCVOA optically coupled to
the first VOS, where the second MCVOA blocks express channels of the
second portion, transmits dropped channels of the second portion, and
balances power levels of each of the transmitted dropped channels of the
second portion.