Survey and Evaluation of Advanced Mobility Management Schemes in the Host Identity Layer

L

Prise de décision de handover vertical pour la gestion de mobilité dans les réseaux hétérogènes sans fil

L évolution des technologies réseaux sans fil, des terminaux mobiles ainsi que des contenus et des services créent des environnements hétérogènes de plus en plus complexes. Dans ce contexte, un compromis entre la mobilité, la transparence et la performance apparaît. Des utilisateurs mobiles, ayant différents profils et préférences, voudraient être toujours connectés au meilleur réseau à tout moment, sans avoir à se soucier des différentes transitions entre réseaux hétérogènes. Face à cette complexité, il parait nécessaire de proposer de nouvelles approches afin de rendre ces systèmes plus autonomes et de rendre les décisions de handover vertical plus efficaces. Cette thèse se concentre sur la gestion de mobilité verticale, plus précisément sur la prise de décision de handover vertical dans un environnement de réseaux hétérogènes sans fil. Après l identification des différents paramètres de prise de décision et l analyse de l état de l art relié à la gestion de la mobilité verticale, nous avons proposé un système de réputation qui permet de réduire les délais de prise de décision. La réputation d un réseau est introduite comme une nouvelle métrique de prise de décision qui peut être recueillie à partir des expériences précédentes des utilisateurs sur ce réseau. Nous montrons que la réputation est une métrique efficace qui permet l anticipation du handover et accélère la prise de décision. Bien que l objectif principal soit de garantir la meilleure qualité de service et l utilisation optimale des ressources radios, les aspects économiques doivent également être considérés, y compris la minimisation des coûts pour les utilisateurs et la maximisation des revenus pour les fournisseurs de services ou les opérateurs. Nous proposons alors, dans la deuxième partie de la thèse, un mécanisme de prise de décision basé sur la théorie des jeux. Ce dernier permet la maximisation des utilités des réseaux et des utilisateurs. Dans cette solution, chaque réseau disponible joue un jeu de Stackelberg avec un ensemble d utilisateurs, tandis que les utilisateurs jouent un jeu de Nash entre eux pour partager les ressources radios limitées. Un point d équilibre de Nash, qui maximise l utilité de l utilisateur et les revenus des fournisseurs de services, est trouvé et utilisé pour le contrôle d admission et la prise de décision de handover vertical. Dans la troisième partie de cette thèse, nous proposons et discutons deux différentes solutions architecturales sur lesquelles nos mécanismes de prise de décision proposés peuvent être intégrés. La première architecture proposée est basée sur la norme IEEE 802.21 à laquelle nous proposons certaines extensions. La seconde architecture proposée est basée sur un niveau de contrôle composé de deux couches de virtualisation. La virtualisation est assurée via des agents capables de faire un raisonnement et de prendre des décisions pour le compte d entités physiques qu ils représentent au sein du système. Cette architecture permet une plus grande flexibilitéMobility management over heterogeneous wireless networks is becoming a major interest area as new technologies and services continue to proliferate within the wireless networking market. In this context, seamless mobility is considered to be crucial for ubiquitous computing. Service providers aim to increase the revenue and to improve users satisfaction. However there are still many technical and architectural challenges to overcome before achieving the required interoperability and coexistence of heterogeneous wireless access networks. Indeed, the context of wireless networks is offering multiple and heterogeneous technologies (e.g. 2G to 4G, WiFi, Wimax, TETRA,...). On the one hand, this rich environment allows users to take profit from different capacities and coverage characteristics. Indeed, this diversity can provide users with high flexibility and allow them to seamlessly connect at any time and any where to the access technology that best fits their requirements. Additionally, cooperation between these different technologies can provide higher efficiency in the usage of the scarce wireless resources offering more economic systems for network providers. On the other hand, the heterogeneity of technologies and architectures and the multiplication of networks and service providers creates a complex environment where cooperation becomes challenging at different levels including and not limited to mobility management, radio resource provisioning, Quality of Service and security guarantees. This thesis is focusing on mobility management and mainly on decision making for Vertical handover within heterogeneous wireless network environments. After the analysis of the related state of the art, we first propose a reputation based approach that allows fast vertical handover decision making. A decision making scheme is then built on that approach. Network s reputation, is a new metric that can be gathered from previous users experiences in the networks. We show that it is an efficient construct to speed up the vertical handover decision making thanks to anticipation functionalities. While the main objective remains guaranteeing the best Quality of Service and optimal radio resource utilization, economical aspects have also to be considered including cost minimization for users and revenue maximization for network providers. For this aim, we propose, in the second part of the thesis, a game theoretic based scheme that allows maximizing benefits for both networks and users. In this solution, each available network plays a Stackelberg game with a finite set of users, while users are playing a Nash game among themselves to share the limited radio resources. A Nash equilibrium point, that maximizes the user s utility and the service provider revenue, is found and used for admission control and vertical handover decision making. The analyses of the optimal bandwidth/prices and the revenue at the equilibrium point show that there are some possible policies to use according to user s requirements in terms of QoS and to network capacities. For instance, we pointed out that networks having same capacities and different reputation values should charge users with different prices which makes reputation management very important to attract users and maximize networks revenue. In the third part of this thesis, we provide and discuss two different architectural and implementation solutions on which our proposed vertical handover decision mechanisms can be integrated. The first proposed architecture is a centralized one. It is based on the IEEE 802.21 standard to which some extensions are proposed. The second proposed architecture is distributed. It is based on an overlay control level composed of two virtualization layers able to make reasoning on behalf of physical entities within the system. This architecture allows higher flexibility especially for loosely coupled interconnected networksEVRY-INT (912282302) / SudocSudocFranceF

On the use of SHIM6 for Mobility Support in IMS Networks

The future of network communications is moving towards deployment of an all-IP core network. This has given rise to many devices hitting the market equipped with multiple network interfaces. However, in order to really benefit from such a heterogeneous network environment, applications must experience minimum disruption as they roam from one network to another, which requires seamless mobility support. Although, some mobility proposals have emerged (Mobile IPv6, and its extensions), none of them give satisfactory performance in terms of handover between different networks. In addition, they require infrastructural changes to the network and give poor performance in case of a failure. In this paper, we propose a mechanism to support mobility through a multi homing SHIM6 layer. The results show that our proposed mechanism outperforms Route Optimized Mobile IPv6

A cross-layer mobility management framework for next-generation wireless roaming

Word processed copy.Includes bibliographical references (leaves 62-64).This thesis proposes a mobility management framework that aims to provide a framework for advanced mobility algorithms that allows the challenges of next-generation roaming to be met. The framework features tools that gather context and content information, guarantee low-level QoS, provide security, and offer link and handoff management. The framework aims to be scalable and reliable for all-IP heterogeneous wireless networks whilst conforming to 4G service requirements

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

Media independent handovers : network selection for mobile IP nodes in heterogeneous wireless networks

Includes abstract.Includes bibliographical references (p. 79-82).In Next Generation Networks (NGN), also known as 4G, Beyond 3G, Converged, Integrated and Interworked Network, user node mobility in wireless and wired environments will seamlessly cross disparate network boundaries. The effort to offer ubiquitous computing, providing access to services anywhere and anytime, strongly encourages the ability to roam across the different existing and future networks. Literature shows investigation of concepts such as Always Best Connected (ABC) when heterogeneous networks co-exist , which will work or compete with other schemes like Home Network Default (HND), Compatibility and Network Operator Agreements (CNOA) to guide network selection or access . With the variety of available networks, the mobile node may be faced with having to decide which network to connect to. We concentrate on the network selection aspects of these envisaged mobile, overlay and integrated environment in heterogeneous networks. The standard developments by the IEEE802.21 Working group and the IETF Networking group form the base of our approach that seeks to see mobility across heterogeneous networks a reality. We propose an IEEE802.21 Media Independent Handover Function (MIHF) based network discovery and network selection, leading to a handover. The selection may be further assisted by an MIHF capable Broker Node that is Third party to the Network Providers to provide a central yet distributed database of the available networks as encountered by the Mobile Node, to cater for Nodes with no prior knowledge of networks and software repository. A Mobile Node (MN) in our solution uses 802.21 communication messages to obtain information about foreign networks encountered before selecting the networks to connect to. Our evaluation through simulations, shows that network selection in heterogeneous wireless networks environment for the appropriately equipped devices is greatly enhanced by the use of the Media Independent Handover Protocol. In scenarios where the mobile node has no prior knowledge of the encountered different network architectures, the use of a Broker node can, for an optimal number of available networks also greatly enhance the mobile node’s network selection by reducing the delay associated and the packet losses incurred

Cross-Layer Handover Scheme for Multimedia Communications in Next GenerationWireless Networks

ROC NSC [97-2221-230 E-018-020-MY3, 98-2218-E-151-004-MY3]In order to achieve seamless handover for real-time applications in the IP Multimedia Subsystem (IMS) of next generation network, a multiprotocol combined handover mechanism is proposed in this paper. We combine SIP (Session Initiation Protocol), FMIP (Fast Mobile IPv6 Protocol), and MIH (Media Independent Handover) protocols by cross-layer design and optimize those protocols' signaling flows to improve the performance of vertical handover. Theoretical analysis and simulation results illustrate that our proposed mechanism performs better than the original SIP and MIH combined handover mechanism in terms of service interruption time and packet loss