 one set are routed on paths completely disjoined by the GLSPs of the other set. Convergent Network Management and Control Plane After that, when performing the optimization, for every link assigned for protection, the sets of the working GLSPs protected through that link are determined and tagged on the link. To assign the protection capacity for a certain working GLSPs, let us say the GLSP with ID equal to 123 belonging to the fourth group, all the protection links that are not tagged with the fourth group are considered available capacity to route the protection GLSP. 8.4.2.2.4 MPLS 1 + 1 or 1:1 Protection In this case, for each MPLS LSP, a protection path has to be preprovisioned that is com- pletely disjoined from the working path. The optimization is carried out using the same approach already used for 1+1 optical protection with a further step: the possibility that new wavelengths have to be introduced due to the need of routing the protection LSPs. Naturally before adding resources to the network the unused resources already present have to be exploited. A new wavelength is introduced on a certain optical link only if no wavelength exists where the working LSP is not multiplexed and with enough free capac- ity to host the protection LSP. 8.4.2.2.5 MPLS Shared Protection In this case, in analogy to what was done for the shared optical protection, before going on with the design of the protection, a data structure has to be constructed where the work- ing LSPs are divided into sets SO that the LSPs of one set are routed on paths completely disjoined by the LSPs of the other set. After that, when performing the optimization for every link assigned for protection, the sets of the working LSPs protecting through that link are determined and tagged on the link. To assign the protection capacity for certain working LSPs, not only the free capacity left by the routing of the working traffic is considered available, but also all that link that has been introduced to route protection paths and that are not tagged w