99 (Re199) is the first UMTS release. It provides a smooth evolution path from GSM/GPRS to UMTS networks. The most important enhancement compared to GSM is the introduction of a new radio interface with WCDMA, which brings a great improvement on the spectrum efficiency and higher data rate to provide a better support for both packet data and circuit-switched data. WCDMA supports data rates up to 2 Mbps in indoor/small-cell- outdoor environments and up to 384 kbps with wide-area coverage, which is in full agreement with the IMT-2000 requirements. WCDMA technology employed on radio interface naturally imposes new requirements to the radio access networks. As WCDMA and its radio access equipment is not compatible with the GSM equipment, it needs additional new network elements (namely RNC and Node B) and new interfaces, which form a new radio access network, i.e. UTRAN. In the Rel99 radio access network, most network intelligence resides in the RNC, which performs most of the Radio Resource Management (RRM) functions such as call admission control, handover, power control, radio access bearer set-up and release, channel allocation, packet scheduling, etc. The Node B manages one or several radio cells and is connected with the RNC over the lub interface. The network architecture of UMTS Rel99 is according to the structure introduced in section 2.2. The corresponding radio interface protocol architecture and the related channels are standardized in [3GP99b]. Section 3.3.2 gives an overview of the channels defined in the 3GPP Rel99. In addition to new network nodes and interfaces, the UTRAN employs a new transport technology. The transport within the radio access network is a very important and crucial aspect. It must provide the support from the RAN for the most efficient utilization of the radio resources. In other words, it should not be a bottleneck between the radio interface and core network. On the other hand, it should also achieve high cost-efficiency on the transport resources (also called backhaul resources)