ansporting all NRT traffic, whose QoS criteria is the average application QoS. And then the total required bandwidth at the backbone link will be the sum of the bandwidth reserved for the RT traffic and the one calculated for the NRT traffic. The desired end-to-end delay factors for different NRT service classes are taking the same values as given in Table 8.6. The network and parameter settings in the investigated simulations are: There are a number of Node Bs in the RAN, structured as a star network architecture. Each last mile link is configured with 1.6 Mbps for the user plane. Each Node B carries seven service classes as same as the ones defined in Table 7.1 in section 7.3.2. The applied QoS structure is illustrated in Figure 3.13. Each Node B generates the same traffic demand, containing 74% Non Real Time (NRT) traffic and 26% Real Time (RT) traffic and in total having around 680 kbps traffic transmitted on the last mile link (equal to 43% last mile utilization). All NRT service classes apply the same web traffic model: page size is 50 kbyte of a constant distribution. The RT traffic includes the voice and the video services, both sharing one Expedited Forwarding (EF) PHB. The traffic models for the RT service classes are same as the ones used in section 7.3.2. In this example, each Node B carries 2 voice connections, 2 video connections, and 3 elastic traffic flows per NRT service class. The configurations for WRED and WFQ functions are given in Table 8.3. Mixed traffic scenario:: 74% NRT + 26% RT Mixed traffic scenario:: 74% NRT + 26% RT M/G/R/N-PS Simulation Number of Node Bs Number of Node Bs (a) overbooking factor (b) relative error Figure 8.23: Overbooking factor vs. the number of Node Bs (mixed traffic scenario) 8 Dimensioning for Multi-lub RAN Scenario In Figure 8.23, the graph (a) shows the derived overbooking factors for different number of Node Bs from both simulation and analytical calculations. The applied analytical dimensioning approach as described in section 8.4.1 is based on the analytical