 the radio access network and each Node B servers a group of elastic traffic flows of the UEs. The IP transport network defines K service classes (PHBs) for the DiffServ QoS, which is applied at every last mile link as well as the backbone link. For the service class k (carried by the kth PHB), the following parameters are defined: Let peak__k denote the peak data rate of the RAB service for the service class k; Let Wk denote the WFQ weight of the service class k on the Kth PHB queue; Let x denote the average file size of the service class k; Let flarget_k denote the target end-to-end delay factor for the service class k; Let fac_k be the target delay factor of the last mile link for the service class k; Let fbb_k be the target delay factor of the backbone link for the service class k. The settings of the above parameters for the service class k are used for all lub interfaces in the multi-lub RAN. In addition, Pk (i) denotes the mean offered traffic of the service class k carried on the ith lub interface corresponding to the Node B i, and N (i) defines the maximum allowed number of flows for the service class k on the ith lub interface. As can be seen from Figure 8.13, the dimensioning for each last mile link and the backbone link is carried out separately with the proposed processor sharing model that is extended for DiffServ for a single link presented in section 7.3.1. For the dimensioning process, the above defined parameters for each service class need to be given as the input parameters. According to the dimensioning procedure described in section 7.3.3, for the individual link, for each service class a required minimum IP bandwidth, which can satisfy the assigned target delay factor of that service class on that link, will be derived numerically with the proposed analytical model presented in section 7.3.1. Then after calculating the required IP bandwidth per service class, the maximum one will be taken to be the dimensioned bandwidth for that link, as it will satisfy the assigned target delay factor of e