ach survivability strategy we will consider three merit parameters. First is the survivability cost efficiency C, which is the percentage of the overall cost expended for working equipment. Convergent Network Management and Control Plane In other words, total network capex - capex for survivability dedicated equipment (8.44) total network capex This parameter represents somehow the results of the design. Besides CE we will consider the average GLSP availability, or better the so-called unavailability (u = 1 - A), and finally the parameter RF2 to characterize the behavior in front of double failure events. The simulation was carried out using the parameters summarized in Tables 8.7 and 8.9 and the main results, which are weakly dependent on traffic as far as the network is cor- rectly dimensioned, are summarized in Table 8.10. The first thing to be noticed is that dedicated protection absorbs about 64% of the net- work cost to deploy protection resources. This is due to the fact that the network connec- tivity is quite low SO that protection paths are quite longer with respect to working paths. This causes DWDM systems used for protection to be much more costly than those used for working traffic. Moreover the protection routes also have an higher number of hops, forcing the nodes to devote a large amount of resources to process transit protection paths. The situation is only a bit better for shared protection. Again, the poor network connec- tivity, which is frequently a characteristic of real geographical networks, forces protection TABLE 8.9 Design Parameters for the Design for Survivability of the North American Network Random Uniform Input/Output LSP between Two Nodes-Distribution Distribution Input/Output LSP between two nodes-min Input/Output LSP between two nodes-max Wavelength channel bit-rate R (Gbit/s) LSPs capacity (Gbit/s) Number of LSP per wavelength Number of wavelength per DWDM system Links average repair time (days) Links average repair time-mission critical traffic Average time between link failu