esired connection rejection ratio pb per last mile link, the capacity of each last mile link Cac_i is calculated by using the MD-Erlang model. The calculated last mile link capacity for 1% connection reject ratio is Cac_i= kbps. It is the same as the simulation results for the last mile link. With the 360 kbps last mile link capacity, the resultant last mile link utilization is 60.8%. Figure 8.2 presents the dimensioning results for the backbone link obtained from simulations and calculations. Figure 8.2(a) shows the required backbone link bandwidths over different number of Node Bs or last mile links, which are calculated from the MMPP/D/1 queuing model for the 1% packet loss ratio (qos bb = 1%). And it is compared with the results obtained from the simulations. For a given number of Node Bs each configured with the calculated last mile link capacity of 360 kbps, the simulations were performed for getting an optimum backbone link bandwidth, which need to transmit the total amount of carried traffic from all last mile links with maximum 1% packet loss ratio over the link. Figure 8.2(b) gives the relative error of the analytical results of using the MMPP/D/1 model. As indicated in Figure 8.2, the analytical results derived from the MMPP/D/1 queuing model matches essentially well with the simulation results. Though the calculated results have some underestimation on the required bandwidth due to the fact that the MMPP arrival process cannot give a perfect estimation of the correlation and burstiness of the aggregated traffic, the obtained relative errors of the MMPP/D/1 model are all below 10% as shown in 8 Dimensioning for Multi-lub RAN Scenario Figure 8.2(b). Therefore it can be concluded that the MMPP/D/1 model gives relatively accurate dimensioning results and thus it can be used to calculate the backbone link capacity for satisfying a defined packet loss ratio. Dimensioning the backbone link for 1% packet loss ratio Dimensioning the backbone link for 1% packet loss ratio 10000 MMPP/D/1 model simulations number