res, while in the case of the other two resto- ration techniques, under the point of view of efficiency they have the same performances. The value of the asymptotic availability, which we will use as a parameter, depends not only on the protection or restoration scheme, but also on the characteristics of the link failure process, on the repair time and on average time passing from the failure discovery to a complete traffic restoration. In case of protection the time needed to restore a connection is assumed deterministic, while in case of restoration the recovery time is assumed a Gaussian random variable due to the need of running signaling protocols for the last two models of restoration and both routing and signaling for the first case. The time this protocol takes to provision and reserve restoration resources depends on the number of nodes to be traversed by the restored path and on the number of GLSPs to be restored. As a matter of fact, in our model, restoration manages each GLSP as an independent connection to be routed using available layer 1 capacity. As expected, the best availability is reached using dedicated protection, networks using bare rerouting restoration have the lower availability. Last, but not least, Table 8.10 shows the value of the reliability coefficient related to double failures. The only scheme that has a reasonable probability to survive to a double failure is the dedicated optical channel protection. As a matter of fact, if two links will fail within a link repair time SO that a double failure situation occurs, the only case in which traffic is lost is the case in which one failure affects a working path and the other the corresponding protection. Convergent Network Management and Control Plane The values of RF2 are much smaller in the case of shared protection, due to the fact that in this case the traffic is lost either if both working and protection path fails and if two working paths sharing the same protection resources fails. In the considered case, the sharing degree (numbe