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 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 .