A distributed impairment aware QoS framework for all-optical networks

Different physical impairments can occur in optical transmission systems. Impairments such as fiber nonlinear effects are dependent on network state and vary with traffic and topology changes. In all-optical networks, impairments can accumulate along a lightpath and cause significant signal degradations. It is important to consider these impairments and the corresponding degradations in the routing algorithm design to provide quality of service (QoS). We propose a distributed QoS framework to achieve traffic engineering and QoS assurance for all-optical networks. Analytical models and new algorithms are designed in the framework to predict lightpath signal quality in dynamic network environments. The framework has also been used to compare performance of several routing and wavelength assignment algorithms with impairments taken into account.