Backup path reprovisioning and activation planning with differentiated dual-failure restorability in WDM mesh networks

A general integer linear programming (ILP) model, which covers all possible second-failure flow recovery cases, is proposed in this paper to capture the structure of the global backup path reprovisioning scheme triggered after the first-failure flow recovery. Backup capacity contention in face of a new failure is resolved by incorporating a priority activation planning process into the model to achieve differentiated dual-failure restorability for two classes of flows. Numerical results show that without increasing the overall network-wide dual-failure non-restorability, the average network-wide dual-failure non-restorability of high class flows is relatively lower than that of low class flows by over 69% with the proposed differentiated backup path reprovisioning and activation planning (RAP) scheme.