1 are regarded as key parameters for the applied dimensioning method. A detailed view of how to derive the minimum required link capacities for the dimensioning output is given Figure 4.6. It is an iterative process. The dimensioning starts with an initial link capacity, and then estimates its resultant QoS for the given traffic demand and network configurations using the selected dimensioning approach. The estimated QoS are compared with the required QoS. If the gap of the estimated QoS and the QoS targets is larger than a predefined convergence threshold, the link capacity need to be increased if the estimated QoS is worse than the required QoS, or decreased if the estimated QoS is better than the required QoS. This iteration process continues until the convergence threshold is reached, i.e. the estimated QoS is close to the required QoS. The outcome of this iteration process is the minimum required link capacity for meeting the QoS requirements of the given traffic demand and network configurations. If choosing analytical dimensioning approaches this process becomes a numerical calculation of the corresponding analytical models. The above presented dimensioning framework and dimensioning procedure are applied in this thesis for the dimensioning of the UMTS lub interface. In order to evaluate the cost- efficiency of the dimensioning results, in this thesis the following metrics are used. Dimensioned bandwidth (kbps): it is the derived bandwidth for the lub interface. It shall be noticed that in this thesis the derived dimensioning bandwidth is given in kbps. However, in practice the dimensioned bandwidth can be mapped to a number of physical 4.3 Framework for UMTS Network Dimensioning lines, dependent on the underlying transport medium. For instance, in an ATM-based UTRAN, the dimensioned link bandwidth can be mapped to a number of E1 lines. Normalized capacity: it is defined as (link bandwidth / traffic load), where the traffic load is represented by the link throughput. It is also called as overdimensioning f