EVEREST IST - 2002 - 00185 : D23 : final report

Deliverable públic del projecte europeu EVERESTThis deliverable constitutes the final report of the project IST-2002-001858 EVEREST. After its successful completion, the project presents this document that firstly summarizes the context, goal and the approach objective of the project. Then it presents a concise summary of the major goals and results, as well as highlights the most valuable lessons derived form the project work. A list of deliverables and publications is included in the annex.Postprint (published version

Queueing Networks for Vertical Handover

PhDIt is widely expected that next-generation wireless communication systems will be heterogeneous, integrating a wide variety of wireless access networks. Of particular interest recently is a mix of cellular networks (GSM/GPRS and WCDMA) and wireless local area networks (WLANs) to provide complementary features in terms of coverage, capacity and mobility support. If cellular/ WLAN interworking is to be the basis for a heterogeneous network then the analysis of complex handover traffic rates in the system (especially vertical handover) is one of the most essential issues to be considered. This thesis describes the application of queueing-network theory to the modelling of this heterogeneous wireless overlay system. A network of queues (or queueing network) is a powerful mathematical tool in the performance evaluation of many large-scale engineering systems. It has been used in the modelling of hierarchically structured cellular wireless networks with much success, including queueing network modelling in the study of cellular/ WLAN interworking systems. In the process of queueing network modelling, obtaining the network topology of a system is usually the first step in the construction of a good model, but this topology analysis has never before been used in the handover traffic study in heterogeneous overlay wireless networks. In this thesis, a new topology scheme to facilitate the analysis of handover traffic is proposed. The structural similarity between hierarchical cellular structure and heterogeneous wireless overlay networks is also compared. By replacing the microcells with WLANs in a hierarchical structure, the interworking system is modelled as an open network of Erlang loss systems and with the new topology, the performance measures of blocking probabilities and dropping probabilities can be determined. Both homogeneous and non-homogeneous traffic have been considered, circuit switched and packet-switched. Example scenarios have been used to validate the models, the numerical results showing clear agreement with the known validation scenarios

Final report on the evaluation of RRM/CRRM algorithms

Deliverable public del projecte EVERESTThis deliverable provides a definition and a complete evaluation of the RRM/CRRM algorithms selected in D11 and D15, and evolved and refined on an iterative process. The evaluation will be carried out by means of simulations using the simulators provided at D07, and D14.Preprin

Energy-efficient vertical handover parameters, classification and solutions over wireless heterogeneous networks: a comprehensive survey

In the last few decades, the popularity of wireless networks has been growing dramatically for both home and business networking. Nowadays, smart mobile devices equipped with various wireless networking interfaces are used to access the Internet, communicate, socialize and handle short or long-term businesses. As these devices rely on their limited batteries, energy-efficiency has become one of the major issues in both academia and industry. Due to terminal mobility, the variety of radio access technologies and the necessity of connecting to the Internet anytime and anywhere, energy-efficient handover process within the wireless heterogeneous networks has sparked remarkable attention in recent years. In this context, this paper first addresses the impact of specific information (local, network-assisted, QoS-related, user preferences, etc.) received remotely or locally on the energy efficiency as well as the impact of vertical handover phases, and methods. It presents energy-centric state-of-the-art vertical handover approaches and their impact on energy efficiency. The paper also discusses the recommendations on possible energy gains at different stages of the vertical handover process

Next generation mobile wireless hybrid network interworking architecture

It is a universally stated design requirement that next generation mobile systems will be compatible and interoperable with IPv6 and with various access technologies such as IEEE 802.11x. Discussion in the literature is currently as to whether the recently developed High Speed Packet Access (HSPA) or the developing Long Term Evaluation (LTE) technology is appropriate for the next generation mobile wireless system. However, the HSPA and the LTE technologies are not sufficient in their current form to provide ubiquitous data services. The third–generation mobile wireless network (3G) provides a highly developed global service to customers through either circuit switched or packet switched networks; new mobile multimedia services (e.g. streaming/mobile TV, location base services, downloads, multiuser games and other applications) that provide greater flexibility for the operator to introduce new services to its portfolio and from the user point of view, more services to select and a variety of higher, on-demand data rates compared with 2.5-2.75G mobile wireless system. However cellular networks suffer from a limited data rate and expensive deployment. In contrast, wireless local area networks (WLAN) are deployed widely in small areas or hotspots, because of their cost-effectiveness, ease of deployment and high data rates in an unlicensed frequency band. On the other hand, WLAN (IEEE 802.11x) cannot provide wide coverage cost-efficiently and is therefore at a disadvantage to 3G in the provision of wide coverage. In order to provide more services at high data rates in the hotspots and campus-wide areas, 3G service providers regard WLAN as a technology that compliments the 3G mobile wireless system. The recent evolution and successful deployment of WLANs worldwide has yielded demand to integrate WLANs with 3G mobile wireless technologies seamlessly. The key goal of this integration is to develop heterogeneous mobile data networks, capable of supporting ubiquitous data services with high data rates in hotspots. The effort to develop heterogeneous networks – also referred to fourth-generation (4G) mobile wireless data networks – is linked with many technical challenges including seamless vertical handovers across WLAN and 3G radio technologies, security, common authentication, unified accounting & billing, WLAN sharing (by several mobile wireless networks – different operators), consistent QoS and service provisioning, etc. This research included modelling a hybrid UMTS/WLAN network with two competent couplings: Tight Coupling and Loose Coupling. The coupling techniques were used in conjunction with EAP-AKA for authentication and Mobile IP for mobility management. The research provides an analysis of the coupling techniques and highlights the advantages and disadvantages of the coupling techniques. A large matrix of performance figures were generated for each of the coupling techniques using Opnet Modeller, a network simulation tool

Energy-efficient vertical handover parameters, classification and solutions over wireless heterogeneous networks: a comprehensive survey

In the last few decades, the popularity of wireless networks has been growing dramatically for both home and business networking. Nowadays, smart mobile devices equipped with various wireless networking interfaces are used to access the Internet, communicate, socialize and handle short or long-term businesses. As these devices rely on their limited batteries, energy-efficiency has become one of the major issues in both academia and industry. Due to terminal mobility, the variety of radio access technologies and the necessity of connecting to the Internet anytime and anywhere, energy-efficient handover process within the wireless heterogeneous networks has sparked remarkable attention in recent years. In this context, this paper first addresses the impact of specific information (local, network-assisted, QoS-related, user preferences, etc.) received remotely or locally on the energy efficiency as well as the impact of vertical handover phases, and methods. It presents energy-centric state-of-the-art vertical handover approaches and their impact on energy efficiency. The paper also discusses the recommendations on possible energy gains at different stages of the vertical handover process

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