Davide Cherubini - PhD Thesis - UniCA Eprints

Chapter 8ConclusionsOptimization problems in telecommunication have been widely studied, mainlyfocusing the improvement of traffic routing within the network.On the other hand, methods to successfully deliver flows in case of failure havebeen slightly explored. I have presented three linear models that cover this lackusing technological and topological constraints derived from the observation ofreal-world telecommunication networks.In particular, the models use an optimal (or suboptimal) configuration of IGP protocolparameters as underlying condition and take advantages carried by TrafficEngineering MPLS techniques in order to find a survivable global configuration.The main goals achieved in this dissertation can be summarized as follows:• optimal configuration in normal working condition, solving the GeneralRouting Problem in a network using IS-IS with complementary MPLS LSPs.• optimal configuration under single link failure condition using IS-IS andMPLS LSPs.• results shown that network operators presence is minimal and is only requestedin the preliminary configuration. Survivability of the service deliveryis guaranteed automatically.• the rule of the “60%” has been revisedThe empiric rule of “60%” states that an upgrade of the network is neededif the link occupation is greater than 60% of its capacity. I have shown that an83