A digital signal channel bypass is provided as bypass around an optical
network optical amplifier, in particular, an analog type optical
amplifier, such as an EDFA, in an optical transport network or system.
The digital signal bypass provides for an ability to maintain the
existing optical amplifier OO amplification site while inserting a bypass
that provides ultra low-cost OEO REGEN in a digital optical network (DON)
utilizing both semiconductor electronic integrated circuit chips and
semiconductor photonic integrated circuit (PIC) chips where all the
optical components are in semiconductor integrated chip form providing
1R, 2R, 3R or 4R regeneration as well as other signal caring
functionality. A salient feature of the digital signal bypass is to
regenerate signals in the optical span that are outside the gain
bandwidth of the EDFA or other such amplifier.