QoS management in UMTS terrestrial radio access FDD networks

This work investigates the role and importance of some of the key aspects of QoS planning, provisioning, monitoring and optimisation (QoS Management) for UMTS Terrestrial Radio Access (UTRA) FDD networks within the framework of the 3rd Generation Partnership Project (3GPP). Firstly, the differences between Quality of end user Experience (QoE) and Quality of Service (QoS) are explained. This is followed by a review of 3GPP requirements for QoS concept and architecture. Then all models and the main assumptions in this dissertation are presented. Based on these, original QoS mechanisms in the radio access network domain, means and methods for QoS provisioning, planning, monitoring and "optimisation" are discussed. Simulation results showed substantial spectral efficiency gains provided by service (or user) differentiation in UTRAN by means of priorities and differentiated parameter settings. When appropriately configured, the proposed QoS mechanisms can greatly reduce the need for bandwidth. Performance results proved also the proposed virtual time simulator to be an appropriate tool for service driven WCDMA radio interface dimensioning and detailed radio network planning. It is also shown that measuring QoS performance by a proper classification of counters (and or gauges), based on a particular subset of radio access bearer attributes, is a promising technique for assessing performances of service applications through WCDMA networks. With this new method there is no need to trace upper layer protocols at different interfaces or dumping data in mobile terminals. The proposed metrics allow operators to measure the bandwidth required for robust statistical reliability, to assess and exploit statistical sharing of resources, to configure QoS functions effectively, and to monitor QoE. The application of the proposed technique is not limited to the WCDMA Radio Network Subsystem (RNS), yet it can be deployed in any radio access and packet core network supporting mapping of performance indicators onto a particular subset of QoS attributes. Finally, in order to maximise the performance of the available services in UTRAN, at a given QoE, simulation results showed clear needs for the network administrator to adapt the parameter settings to diverse input application traffic conditions and the proposed genetic approach to be an appropriate solution space search algorithm for this purpose.reviewe

Accepting the challenges of IP-based UMTS radio access network evolution scenarios

The tendency in future mobile Radio Access Networks (RANs) consists in an increase of new and Internet Protocol (IP)-based services with strict requirements regarding bandwidth and Quality of Service (QoS) and in a dominance of packet data traffic in future mobile networks. Existing mobile networks (e.g. Universal Mobile Telecommunications System (UMTS) Release 99 (R99)), which are designed assuming a predominance of circuit switched traffic, are not suitable to efficiently carry IP traffic under consideration of the hierarchical and centralistic network structure of existing mobile networks, the coupling of user and control plane and the strict delay requirements in the RAN. Consequently, an architecture evolution of mobile RANs with regard to their network architecture has to take place. Within the cooperation of Lucent Technologies and the University of Duisburg-Essen in the project IPonAir, funded by the German Ministry for Education and Research (Bundesministerium für Bildung und Forschung (BMBF)), and within the work carried out for this thesis, a flexible, efficient and toolsupported approach was developed that allows for an evaluation of future mobile RANs with regard to signaling performance. This approach provides decision support to the designer of future mobile networks in a very early design phase. The evaluation approach comprises a methodology for eventdriven simulation of signaling sequences, depicted in the form of Message Sequence Charts (MSCs), as well as a toolkit – both, i.e. the simulation methodology as well as the toolkit, enable an optimization as well as an assessment of future mobile RANs with regard to signaling performance as well as a comparison with the UMTS R99 as a reference architecture. In the thesis on hand, the above mentioned evaluation approach is presented in detail. Moreover, the approach is applied to potential evolution scenarios of mobile RANs. On the one hand these RAN evolution scenarios are optimized with regard to signaling performance. On the other hand the RAN evolution scenarios are compared to the UMTS R99 reference architecture with regard to their signaling performance behavior