Joint capacity assignment to state-independent working and spare paths for enchanced network survivability

To develop survivable and cost-efficient networks, it is important to consider practical restoration control in network design. We propose a design for joint capacity assignment to state-independent working paths and state-independent spare paths. The assignment is formulated as an integer programming problem. The use of state-independent paths simplifies the restoration process and shortens the restoration time, and our design is especially suitable to pre-planned distributed restoration schemes. We further apply it to a strategy in which all paths are state-dependent, and to one whose spare paths are state-dependent. A numerical comparison of capacity costs, in which our design was applied to specific network examples, shows that costs for a state-independent approach are only slightly higher than those for state-dependent approach.