Oligopolistic competition in heterogeneous access networks under asymmetries of cost and capacity

With the rapid development of broadband wireless access technologies, multiple wireless service provider (WSPs) operating on various wireless access technologies may coexist in one service area to compete for users, leading to a highly competitive environment for the WSPs. In such a competitive heterogeneous wireless access market, different wireless access technologies used by different WSPs have different bandwidth capacities with various costs. In this paper, we set up a noncooperative game model to study how the cost asymmetry and capacity asymmetry among WSPs affect the competition in this market. We first model such a competitive heterogeneous wireless access market as an oligopolistic price competition, in which multiple WSPs compete for a group of price- and delay-sensitive users through their prices, under cost and capacity asymmetries, to maximize their own profits. Then, we develop an analytical framework to investigate whether or not a Nash equilibrium can be achieved among the WSPs in the presence of the cost and capacity asymmetries, how the asymmetries of cost and capacity affect their equilibrium prices and what impact a new WSP with a cost and capacity advantage entering the market has on the equilibrium achieved among existing WSPs

Multimedia session continuity in the IP multimedia subsystem : investigation and testbed implementation

Includes bibliographical references (leaves 91-94).The advent of Internet Protocol (IP) based rich multimedia services and applications has seen rapid growth and adoption in recent years, with an equally increasing user base. Voice over IP (VoIP) and IP Television (IPTV) are key examples of services that are blurring the lines between traditional stove-pipe approach network infrastructures. In these, each service required a different network technology to be provisioned, and could only be accessed through a specific end user equipment (UE) technology. The move towards an all-IP core network infrastructure and the proliferation of multi-capability multi-interface user devices has spurred a convergence trend characterized by access to services and applications through any network, any device and anywhere

A Seamless Vertical Handoff Protocol for Enhancing the Performance of Data Services in Integrated UMTS/WLAN Network

The Next Generation Wireless Network (NGWN) is speculated to be a unified network composed of several existing wireless access networks such as Wireless Local Area Network (WLAN), Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and satellite network etc

A Unified Mobility Management Architecture for Interworked Heterogeneous Mobile Networks

The buzzword of this decade has been convergence: the convergence of telecommunications, Internet, entertainment, and information technologies for the seamless provisioning of multimedia services across different network types. Thus the future Next Generation Mobile Network (NGMN) can be envisioned as a group of co-existing heterogeneous mobile data networking technologies sharing a common Internet Protocol (IP) based backbone. In such all-IP based heterogeneous networking environments, ongoing sessions from roaming users are subjected to frequent vertical handoffs across network boundaries. Therefore, ensuring uninterrupted service continuity during session handoffs requires successful mobility and session management mechanisms to be implemented in these participating access networks. Therefore, it is essential for a common interworking framework to be in place for ensuring seamless service continuity over dissimilar networks to enable a potential user to freely roam from one network to another. For the best of our knowledge, the need for a suitable unified mobility and session management framework for the NGMN has not been successfully addressed as yet. This can be seen as the primary motivation of this research. Therefore, the key objectives of this thesis can be stated as: To propose a mobility-aware novel architecture for interworking between heterogeneous mobile data networks To propose a framework for facilitating unified real-time session management (inclusive of session establishment and seamless session handoff) across these different networks. In order to achieve the above goals, an interworking architecture is designed by incorporating the IP Multimedia Subsystem (IMS) as the coupling mediator between dissipate mobile data networking technologies. Subsequently, two different mobility management frameworks are proposed and implemented over the initial interworking architectural design. The first mobility management framework is fully handled by the IMS at the Application Layer. This framework is primarily dependant on the IMS’s default session management protocol, which is the Session Initiation Protocol (SIP). The second framework is a combined method based on SIP and the Mobile IP (MIP) protocols, which is essentially operated at the Network Layer. An analytical model is derived for evaluating the proposed scheme for analyzing the network Quality of Service (QoS) metrics and measures involved in session mobility management for the proposed mobility management frameworks. More precisely, these analyzed QoS metrics include vertical handoff delay, transient packet loss, jitter, and signaling overhead/cost. The results of the QoS analysis indicates that a MIP-SIP based mobility management framework performs better than its predecessor, the Pure-SIP based mobility management method. Also, the analysis results indicate that the QoS performances for the investigated parameters are within acceptable levels for real-time VoIP conversations. An OPNET based simulation platform is also used for modeling the proposed mobility management frameworks. All simulated scenarios prove to be capable of performing successful VoIP session handoffs between dissimilar networks whilst maintaining acceptable QoS levels. Lastly, based on the findings, the contributions made by this thesis can be summarized as: The development of a novel framework for interworked heterogeneous mobile data networks in a NGMN environment. The final design conveniently enables 3G cellular technologies (such as the Universal Mobile Telecommunications Systems (UMTS) or Code Division Multiple Access 2000 (CDMA2000) type systems), Wireless Local Area Networking (WLAN) technologies, and Wireless Metropolitan Area Networking (WMAN) technologies (e.g., Broadband Wireless Access (BWA) systems such as WiMAX) to interwork under a common signaling platform. The introduction of a novel unified/centralized mobility and session management platform by exploiting the IMS as a universal coupling mediator for real-time session negotiation and management. This enables a roaming user to seamlessly handoff sessions between different heterogeneous networks. As secondary outcomes of this thesis, an analytical framework and an OPNET simulation framework are developed for analyzing vertical handoff performance. This OPNET simulation platform is suitable for commercial use

A Seamless Vertical Handoff Protocol for Enhancing the Performance of Data Services in Integrated UMTS/WLAN Network

The Next Generation Wireless Network (NGWN) is speculated to be a unified network composed of several existing wireless access networks such as Wireless Local Area Network (WLAN), Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and satellite network etc

A Modelling Framework for Common Radio Resource Management in Mobile Communication Systems

Im Rahmen dieser Arbeit wurde ein Modellierungsframework für die Untersuchung der technologieübergreifenden Verwaltung von Ressourcen heterogener Funkzugangsnetze (Common Radio Resource Management – CRRM) entwickelt. Die fünf Komponenten Umwelt (ENV), Nutzerendgerät (UE), Funkzugangssystem (RAS), CRRM-Informationsmanager (CRRM-IM) und CRRM-Entscheider (CRRM-D) können für die Gestaltung von zentralen bis dezentralen CRRM-Architekturen kombiniert werden. Sie decken damit ein weites Spektrum an möglichen CRRM-Einsatzszenarien ab. Dabei ermöglicht eine klare Struktur des zugrunde liegenden Modells die einfache Übertragung von Lösungsmethoden aus dem Gebiet der Multikriterienoptimierung. Ein integriertes Kostenmodell ermöglicht eine Kosten-/ Nutzen-Analyse für CRRM-Algorithmen und Architekturen. Die Verwendung eines hybriden Simulationsmodells ermöglicht die einfache Integration analytischer Funkzugangstechnologiemodelle und die Simulation komplexer Szenarien mit geringem Zeit- und Speicherbedarf. Hierbei liefern simulative Teilmodelle zeitgetreu neue Eingabeparameter für analytische Teilmodelle, deren Ausgabeparameter wiederum die Eingabeparameter der simulativen Teilmodelle sind. Nach diesem Modell wurde der auf OMNeT++ basierende diskrete ereignisorientierte Simulator HEKATE entwickelt. Der Simulator erwies sich als geeignet die zeiteffiziente Untersuchung von CRRM-Szenarien für UMTS- und GSM/EGPRS-Funkzugangssysteme durchzuführen.This work presents a modeling framework for the efficient evaluation of Common Radio Resource Management (CRRM). Centralized as well as decentralized scenarios can be clearly defined by five standard components, namely the radio access system (RAS), the environment (ENV), the user equipment (UE), the CRRM information manager (CRRM-IM), and the CRRM decider (CRRM-D). The clarity of the model enables an efficient investigation of CRRM algorithms based on multi-criteria optimization theory. The integrated cost model makes possible a cost-benefit investigation of different CRRM algorithms and architectures. A hybrid simulation model, where a simulation model and an analytical model operate in parallel over time, leads to low time and memory demands even for the simulation of complex scenarios. Additionally it allows for a convenient and straightforward integration of different analytical models for wireless network technologies. A discrete event simulator named HEKATE is based on this hybrid simulation model which has been implemented using OMNeT++. The scope of the proposed framework is demonstrated by the evaluation of realistic CRRM scenarios for UMTS and GSM/EGPRS

Fast and seamless mobility management in IPV6-based next-generation wireless networks

Introduction -- Access router tunnelling protocol (ARTP) -- Proposed integrated architecture for next generation wireless networks -- Proposed seamless handoff schemes in next generation wireless networks -- Proposed fast mac layer handoff scheme for MIPV6/WLANs