Supporting differentiated survivability services in WDM optical networks

Optical networks are currently widely employed to support a variety of telecommunications and other applications. In order to provide the increased bandwidth needed by the existing and emerging applications, optical networks rely extensively on wavelength division multiplexing (WDM). In these networks, WDM is not only used to satisfy capacity requirements, but it can be also exploited to offer advanced features and functionalities such as service differentiation, varying QoS guarantees etc. This paper studies the use of WDM in core optical networks with focus on resilience issues. More specifically the use and suitability of WDM to support differentiated survivability requirements of traffic generated by different applications are investigated. The proposed approach combines various routing and wavelength assignment schemes with the aim to facilitate efficient resource sharing, thus leading into significant enhancement of the spare capacity utilization, as demonstrated by our evaluation results. At the same time, routing and wavelength assignment can be used to differentiate various classes of services based on their survivability requirements. Simulations have shown significant network performance improvement through the proposed approach compared to conventional solutions that do not include survivability differentiation between services.