Optical communication networks often incorporate fiber rings or fiber mesh
topologies for interconnecting its nodes. Both of these topologies can
contain closed optical loops at one or more wavelengths within the
optical spectrum. In amplified optical systems, the inherent loss of
these optical loops is counteracted by the amplifier gain. Thus, the
optical loop may have a net loss that is too low to prevent excessive
noise buildup resulting in a lasing fiber loop. The noise that builds up
within such amplified systems is dominated by the Amplified Spontaneous
Emission (ASE) noise resulting in ASE loops. Such loops can have a
serious impact on all wavelengths carried by the fiber and lead to a
partial or complete loss of end to end communication due to a severe
degradation in signal to noise ratio. This invention provides an
effective method and system for avoiding ASE loops in optical
communication networks. The method deploys optical seams as well as a
unique signature for a wavelength instance for achieving an effective
solution that is resilient to errors and failures that may occur on the
system both during service creation and normal operation.