A decomposition approach to assign spare channels in self-healing networks

Intelligent transmission network elements such as digital cross connect systems and add/drop multiplexers enable network restoration by dynamic reconfiguration of the network during failure events. Fast line and path restoration is possible by pre-assigning spare capacity to network links. The paper suggests a decomposition approach for the task of finding an economic placement of spare channels in trunk networks to cope with single link failures. The approach is based on a set of properties derived from a linear programming network model which was published in this area. Under reasonable assumptions, the decomposition approach often leads to an optimal solution. A numerical example, considered already in the literature, is analysed by network decomposition to illustrate the merits of the approach developed