otection of these LSRs is with the SP-R method but with type 2 instead that type 1 restoration at MPLS layer. Moreover the SLA relative to this traffic type foresees a repair time of only 4 days against any type of link failure. It is to be noticed that LSPs belonging to class 4 can run on the same fibers where class 3 services run, but not on the same wavelengths. As a matter of fact, wave- lengths accommodating class 4 services have to be protected at the optical layer as a whole, but this is not true for wavelength containing LSPs of class 3. From the earlier discussion, it results that, as a consequence of the differentiation of the classes of service of the GLSPs, the wavelengths are also differentiated. In particular, there are the following types of wavelengths: Type 1 wavelengths: Containing working LSPs of classes 1 and 2 and spare capac- ity to be used by Layer 2 restoration processes. This last capacity can be occupied by low-priority traffic (service level 0). Convergent Network Management and Control Plane Type 2 wavelengths containing service level 3 LSPs and spare capacity to be used by Layer 2 restoration processes. This last capacity can be occupied by low-priority traffic (service level 0). Type 3 wavelengths containing service level 4 LSPs. Both protection and working paths are considered type 3 wavelengths, since they have no difference under a traffic load point of view but for the fact that at the receiver the working path is selected whenever possible. Type 4 wavelengths that convey spare capacity to be used by restoration at layer 1 and can support low-priority traffic. To dimension a network with a SO complex traffic demand and survivability technique with IPL optimization in only two steps, one for capacity managing working traffic the other for capacity for use as a back-up is naturally possible under a theoretical point of view, but difficult to do with a realistic computation machine. It is to be noted however that the introduction of different classes of wavelength, practically segme