run a network and keep it in an operational state. Within the network operation, various actions can be taken to assure the desired QoS such as traffic control, resource control, rerouting. Traffic control provides fundamental techniques on the packet level to differentiate and manage different traffic streams in order to achieve service-specific QoS for all traffic flows traversing the network. It includes technologies such as packet classification, scheduling, buffer management and traffic policing. Resource control refers to techniques which manage the access to available network resources at class, flow or connection level to keep the network from being overloaded and services from experiencing quality degradation. Rerouting takes place when the network topology changes due to temporary link or node failures. During the operation process, the operational state has to be continuously monitored in order to verify whether it conforms to the predefined requirements. As soon as a non- satisfactory state is indicated, countermeasures have to be taken. Usually such non- satisfactory states are caused by traffic overload situations, which might arise due to the increasing traffic demand or temporary traffic variations. The overload situations can be alleviated through network management procedures, such as routing optimization or dimensioning update (adaptation of bandwidth assignment). In either case the new configuration is uploaded to the network and network operation is continued. However, if the existing infrastructure is not sufficiently dimensioned to support traffic increases or new services, the network has to be extended. It often requires an adaptation of the network topology, which poses a redesign of the network. And therefore, the routing needs to be re- optimized, and re-dimensioning is needed for the extended network to add new links or extend the capacities for the existing links. From this procedure, it is clearly seen that the dimensioning tasks arise at each phase throughout the network planning c