Restoration capacity for resilient wavelength-routed optical transport networks

The design of resilient wavelength-routed optical network (WRON) architectures is key for telecom operators to deploy the WDM optical transport layer. Link failures due to cable cuts have been widely recognised to have the most significant impact on the network performance. For optical restoration, the utilised strategy is crucial in determining the spare capacity requirement. Different survivability techniques have recently been analysed, and results reported. However, the influence of the physical topology on the restoration capacity has not been identified, particularly in comparison to the strategies available at the higher network layers, such as SONET/SDH. In this work, we analyse several different network topologies which provide full traffic restoration for single link failures. The results show that restoration capacity requirements are critically affected by the physical connectivity.