 required link capacities which should satisfy the desired QoS requirements. As mentioned at the beginning of this chapter, the goal of network dimensioning is to minimize the total network cost while maximizing the QoS to achieve a cost-effective radio access network. In this thesis, the dimensioning is specifically focused on the lub interface within the UTRAN network. 4.3 Framework for UMTS Network Dimensioning Inputs Outputs traffic demand traffic class (application / service) Network Cost traffic load Dimensioning determine the traffic distribution (traffic mix) Process minimum required desired QoS targets link capacities (kbps) user-relevant QoS network-relevant QoS Network Configurations network topology (single link, star topology, etc.) traffic control (scheduling, shaping, buffering, etc.) resource control (CAC, BRA, etc.) transport technology (ATM or IP) - protocol overheads - packet size QoS schemes (Strict Priority, DiffServ, etc.) Figure 4.4: UMTS network dimensioning framework As indicated in Figure 4.4, for carrying out the dimensioning, two types of input data are required: Traffic Demand The traffic demand refers to the requirements of the traffic in the network, which specifies the total amount of the offered traffic, the traffic classes with respective to different services and applications as well as the traffic distribution in terms of a variation of traffic mix. The traffic demand is the outcome of traffic analysis in the framework of the network design process (see section 4.2.1). Desired QoS Targets The QoS targets define the QoS requirements that need to be satisfied by the network. It describes the objective of the network dimensioning. As introduced in section 4.1.2, two types of QoS are considered: user-relevant QoS and network- relevant QoS. Additionally, different Network Configurations need to be taken into consideration for the dimensioning. As discussed in section 4.2, they have considerable impact on the transmitted traffic in the transport network (traffic characteristics and l