A network-based coordination design for seamless handover between heterogeneous wireless networks

Includes bibliographical references (leaves 136-144).The rapid growth of mobile and wireless communication over the last few years has spawned many different wireless networks. These heterogeneous wireless networks are envisioned to interwork over an IP-based infrastructure to realize ubiquitous network service provisioning for mobile users. Moreover, the availability of multiple-interface mobile nodes (MNs) will make it possible to communicate through any of these wireless access networks. This wireless network heterogeneity combined with the availability of multiple-interface MNs creates an environment where handovers between the different wireless access technologies become topical during mobility events. Therefore, operators with multiple interworking heterogeneous wireless networks will need to facilitate seamless vertical handovers among their multiple systems. Seamless vertical handovers ensure ubiquitous continuity to active connections hence satisfy the quality of experience of the mobile users

Future Trends and Challenges for Mobile and Convergent Networks

Some traffic characteristics like real-time, location-based, and community-inspired, as well as the exponential increase on the data traffic in mobile networks, are challenging the academia and standardization communities to manage these networks in completely novel and intelligent ways, otherwise, current network infrastructures can not offer a connection service with an acceptable quality for both emergent traffic demand and application requisites. In this way, a very relevant research problem that needs to be addressed is how a heterogeneous wireless access infrastructure should be controlled to offer a network access with a proper level of quality for diverse flows ending at multi-mode devices in mobile scenarios. The current chapter reviews recent research and standardization work developed under the most used wireless access technologies and mobile access proposals. It comprehensively outlines the impact on the deployment of those technologies in future networking environments, not only on the network performance but also in how the most important requirements of several relevant players, such as, content providers, network operators, and users/terminals can be addressed. Finally, the chapter concludes referring the most notable aspects in how the environment of future networks are expected to evolve like technology convergence, service convergence, terminal convergence, market convergence, environmental awareness, energy-efficiency, self-organized and intelligent infrastructure, as well as the most important functional requisites to be addressed through that infrastructure such as flow mobility, data offloading, load balancing and vertical multihoming.Comment: In book 4G & Beyond: The Convergence of Networks, Devices and Services, Nova Science Publishers, 201

Mobility management across converged IP-based heterogeneous access networks

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 8/2/2010.In order to satisfy customer demand for a high performance “global” mobility service, network operators (ISPs, carriers, mobile operators, etc.) are facing the need to evolve to a converged “all-IP” centric heterogeneous access infrastructure. However, the integration of such heterogeneous access networks (e.g. 802.11, 802.16e, UMTS etc) brings major mobility issues. This thesis tackles issues plaguing existing mobility management solutions in converged IP-based heterogeneous networks. In order to do so, the thesis firstly proposes a cross-layer mechanism using the upcoming IEEE802.21 MIH services to make intelligent and optimized handovers. In this respect, FMIPv6 is integrated with the IEEE802.21 mechanism to provide seamless mobility during the overall handover process. The proposed solution is then applied in a simulated vehicular environment to optimize the NEMO handover process. It is shown through analysis and simulations of the signalling process that the overall expected handover (both L2 and L3) latency in FMIPv6 can be reduced by the proposed mechanism by 69%. Secondly, it is expected that the operator of a Next Generation Network will provide mobility as a service that will generate significant revenues. As a result, dynamic service bootstrapping and authorization mechanisms must be in place to efficiently deploy a mobility service (without static provisioning), which will allow only legitimate users to access the service. A GNU Linux based test-bed has been implemented to demonstrate this. The experiments presented show the handover performance of the secured FMIPv6 over the implemented test-bed compared to plain FMIPv6 and MIPv6 by providing quantitative measurements and results on the quality of experience perceived by the users of IPv6 multimedia applications. The results show the inclusion of the additional signalling of the proposed architecture for the purpose of authorization and bootstrapping (i.e. key distribution using HOKEY) has no adverse effect on the overall handover process. Also, using a formal security analysis tool, it is shown that the proposed mechanism is safe/secure from the induced security threats. Lastly, a novel IEEE802.21 assisted EAP based re-authentication scheme over a service authorization and bootstrapping framework is presented. AAA based authentication mechanisms like EAP incur signalling overheads due to large RTTs. As a result, overall handover latency also increases. Therefore, a fast re-authentication scheme is presented which utilizes IEEE802.21 MIH services to minimize the EAP authentication process delays and as a result reduce the overall handover latency. Analysis of the signalling process based on analytical results shows that the overall handover latency for mobility protocols will be approximately reduced by 70% by the proposed scheme

A QoS-aware architecture for mobile internet

Tese de doutoramento InformáticaHoje em dia, as pessoas pretendem ter simultaneamente mobilidade, qualidade de serviço e estar sempre connectados à Internet. No intuito, de satisfazer estes clientes muito exigentes, os mercados das telecomunicações estão a impor novos e dificeis desafios às redes móveis, através da demanda, de heterogeneidade em termos de tecnologias de acesso rádio, novos serviços, niveis de qualidade de serviço adequados aos requisitos das aplicações de tempo real, elevada taxa de utilização do recursos disponiveis e melhor capacidade de desempenho. A Internet foi concebida para fornecer serviços sem qualquer tipo de garantias de qualidade às aplicações, apenas se comprometendo em oferecer o melhor serviço possível. No entanto, nos útlimos anos diversos esforços foram levados a cabo no sentido de dotar a Internet com o suporte à qualidade de serviço. Dos esforços desenvolvidos resultaram dois paradigmas para o suporte da qualidade de serviço: o modelo de Serviços Integrados (Integrated Services - IntServ) e o modelo de Serviços Diferenciados (Differentiated Services - DiffServ). Todavia, estes modelos de qualidade de serviço (QoS) foram concebido antes da existência da Internet móvel, portanto o desenvolvimento destes modelos não teve em consideração a questão da mobilidade. Por outro lado, o protocolo padrão actual para a Internet móvel, o MIPv6, revela algumas limitações nos cenários onde os utilizadores estão constantemente a moverem-se para outros pontos de acesso. Neste tipo de cenários, o MIPv6 introduz tempos de latência que não são sustentáveis para aplicações com requisitos de QoS mais restritos. Os factos revelados, demonstram que existe uma emergente necessidade de adaptar o actual protocolo de mobilidade, e também de adaptar os modelos de QoS, ou então criar modelos alternativos de QoS, para satisfazer às exigências do utilizador de hoje de redes móveis. Para alcançar este objectivo o presente trabalho propõe melhorias no sistema de gestão da mobilidade do protocolo MIPv6 e na gestão de recursos do modelo DiffServ. O MIPv6 foi melhorado para os cenários de micro-mobilidade com a abordagem para micro-mobilidade do F-HMIPv6. Enquanto que, o modelo DiffServ foi melhorado para os ambientes móveis com funcionalidades dinâmicas e adaptativas através da utilização de sinalização de QoS e da gestão distribuida dos recursos. A gestão da mobilidade e dos recursos foi também acoplada na solução proposta com o propósito de optimizar a utilização dos recursos num meio onde os recursos são tipicamente escassos. O modelo proposto é simples, é de fácil implementação, tem em consideração os requisitos da Internet móvel, e provou ser eficiente e capaz de fornecer serviços com QoS de elevada fiabilidade às aplicações.Over the last few years, several network communication challenges have arisen as a result of the growing number of users demanding Quality of Service (QoS) and mobility simultaneously. In order to satisfy these very demanding customers, the markets are imposing new challenges to wireless networks by demanding heterogeneity in terms of wireless access technologies, new services, suited QoS levels to real-time applications, high usability and improved performance. However, the Internet has been designed for providing application services without quality guarantees. That explains why, in the last years several efforts have been made to endow Internet with QoS support. From the developed efforts have resulted two QoS paradigms: Integrated Services (IntServ) which offers the guaranteed service model and the Differentiated Services (DiffServ) which offers the predictive service model. Although these QoS models have been designed before the existence of mobile Internet, so they do not consider the mobility issue. For instance, the guaranteed service model requires that whenever a Mobile Node (MN) wants to move to a new location, the allocated resources in the old path must be released and a new resource reservation in a new path must be made, resulting in extra signaling overhead, heavy processing and state load. Therefore, if handovers are frequent, large mobility and QoS signaling messages will be created in the access networks. Consequently, significant scalability problems may arise with this type of service model. The predicted service model, on the other hand, requires an additional features such as dynamic and adaptive resource management in order to be efficient in a very dynamic network such as a mobile network. A QoS solution for mobile environments must provide the capacity to adapt its resource utilization to a changeable nature of wireless networks because they have a more dynamic behavior due to incoming or outgoing handovers. For this reason, a QoS signalization for dynamic resource provisioning is necessary in order to supply adequate QoS levels to mobile users. On the other hand, the current standard protocol for mobile Internet, Mobile IPv6 (MIPv6), reveals limitations in scenarios where users are constantly moving to another point of attachment. In these situations, MIPv6 introduces latency times that are not sustainable for applications with strict QoS requirements. All things considered, reveal the emerging need to adapt the current standard mobility protocol and QoS models to satisfy today’s mobile user’s requirements. To accomplish this goal, the present work proposes enhancements in terms of the MIPv6 protocol mobility management scheme as well as in DiffServ QoS model resource management. The former was enhanced for micro-mobility scenarios with a specific combination of FMIPv6 (Fast Mobile IPv6) and HMIPv6 (Hierarchical Mobile IPv6) protocols. Whereas, the latter was enhanced for mobile environments with dynamic and adaptive features by using QoS signalization as well as distributed resource management. The mobility and resource management has also been coupled in the proposed solution with the objective of optimizing the resource utilization in a environment where resources are typically scarce. In order to assess model performance as well as its parametrization, a simulation model has been designed and implemented in the Network Simulator version two (NS-2). The model´s performance evaluation has been conducted based on the respective data acquired from statistical analysis in order to validate and consolidate the conclusions. Simulation results indicate that the solution avoids network congestion and starvation of less priority DiffServ classes. Moreover, the results also indicate that bandwidth utilization for priority classes increases and the QoS offered to MN’s applications, in each DiffServ class, remains unchangeable with MN mobility. The proposed model is simple and easy to implement. It considers mobile Internet requirements and has proven to be effective and capable of providing services with highly reliable QoS to mobile applications.Fundação para a Ciência e a Tecnologia (FCT) - Bolsa SFRH/BD/35245/200

Mobility management across converged IP-based heterogeneous access networks

In order to satisfy customer demand for a high performance “global” mobility service, network operators (ISPs, carriers, mobile operators, etc.) are facing the need to evolve to a converged “all-IP” centric heterogeneous access infrastructure. However, the integration of such heterogeneous access networks (e.g. 802.11, 802.16e, UMTS etc) brings major mobility issues. This thesis tackles issues plaguing existing mobility management solutions in converged IP-based heterogeneous networks. In order to do so, the thesis firstly proposes a cross-layer mechanism using the upcoming IEEE802.21 MIH services to make intelligent and optimized handovers. In this respect, FMIPv6 is integrated with the IEEE802.21 mechanism to provide seamless mobility during the overall handover process. The proposed solution is then applied in a simulated vehicular environment to optimize the NEMO handover process. It is shown through analysis and simulations of the signalling process that the overall expected handover (both L2 and L3) latency in FMIPv6 can be reduced by the proposed mechanism by 69%. Secondly, it is expected that the operator of a Next Generation Network will provide mobility as a service that will generate significant revenues. As a result, dynamic service bootstrapping and authorization mechanisms must be in place to efficiently deploy a mobility service (without static provisioning), which will allow only legitimate users to access the service. A GNU Linux based test-bed has been implemented to demonstrate this. The experiments presented show the handover performance of the secured FMIPv6 over the implemented test-bed compared to plain FMIPv6 and MIPv6 by providing quantitative measurements and results on the quality of experience perceived by the users of IPv6 multimedia applications. The results show the inclusion of the additional signalling of the proposed architecture for the purpose of authorization and bootstrapping (i.e. key distribution using HOKEY) has no adverse effect on the overall handover process. Also, using a formal security analysis tool, it is shown that the proposed mechanism is safe/secure from the induced security threats. Lastly, a novel IEEE802.21 assisted EAP based re-authentication scheme over a service authorization and bootstrapping framework is presented. AAA based authentication mechanisms like EAP incur signalling overheads due to large RTTs. As a result, overall handover latency also increases. Therefore, a fast re-authentication scheme is presented which utilizes IEEE802.21 MIH services to minimize the EAP authentication process delays and as a result reduce the overall handover latency. Analysis of the signalling process based on analytical results shows that the overall handover latency for mobility protocols will be approximately reduced by 70% by the proposed scheme.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Mobility management across converged IP-based heterogeneous access networks

In order to satisfy customer demand for a high performance “global” mobility service, network operators (ISPs, carriers, mobile operators, etc.) are facing the need to evolve to a converged “all-IP” centric heterogeneous access infrastructure. However, the integration of such heterogeneous access networks (e.g. 802.11, 802.16e, UMTS etc) brings major mobility issues. This thesis tackles issues plaguing existing mobility management solutions in converged IP-based heterogeneous networks. In order to do so, the thesis firstly proposes a cross-layer mechanism using the upcoming IEEE802.21 MIH services to make intelligent and optimized handovers. In this respect, FMIPv6 is integrated with the IEEE802.21 mechanism to provide seamless mobility during the overall handover process. The proposed solution is then applied in a simulated vehicular environment to optimize the NEMO handover process. It is shown through analysis and simulations of the signalling process that the overall expected handover (both L2 and L3) latency in FMIPv6 can be reduced by the proposed mechanism by 69%. Secondly, it is expected that the operator of a Next Generation Network will provide mobility as a service that will generate significant revenues. As a result, dynamic service bootstrapping and authorization mechanisms must be in place to efficiently deploy a mobility service (without static provisioning), which will allow only legitimate users to access the service. A GNU Linux based test-bed has been implemented to demonstrate this. The experiments presented show the handover performance of the secured FMIPv6 over the implemented test-bed compared to plain FMIPv6 and MIPv6 by providing quantitative measurements and results on the quality of experience perceived by the users of IPv6 multimedia applications. The results show the inclusion of the additional signalling of the proposed architecture for the purpose of authorization and bootstrapping (i.e. key distribution using HOKEY) has no adverse effect on the overall handover process. Also, using a formal security analysis tool, it is shown that the proposed mechanism is safe/secure from the induced security threats. Lastly, a novel IEEE802.21 assisted EAP based re-authentication scheme over a service authorization and bootstrapping framework is presented. AAA based authentication mechanisms like EAP incur signalling overheads due to large RTTs. As a result, overall handover latency also increases. Therefore, a fast re-authentication scheme is presented which utilizes IEEE802.21 MIH services to minimize the EAP authentication process delays and as a result reduce the overall handover latency. Analysis of the signalling process based on analytical results shows that the overall handover latency for mobility protocols will be approximately reduced by 70% by the proposed scheme.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Intelligent seamless handover in next generation networks

Providing high quality of service (QoS) to mobile end-users, and guaranteeing resilient connectivity for healthcare wearables and other mobile devices is a critical component of Industry 5.0. However, one of the biggest difficulties that network operators encounter is the issue of mobility handover, as it can be detrimental to end-users’ safety and experience. Although various handover mechanisms have been developed to meet high QoS, achieving optimum handover performance while maintaining sustainable network operation is still an unreached goal. In this paper, random linear codes (RLC) are used to achieve seamless handover, where handover traffic is encoded using RLC and then multicasted to handover destination(s) using a mobility prediction algorithm for destination selection. To overcome the limitations of current IP core networks, we make use of a revolutionary IP-over-Information-Centric Network architecture at the network core that supports highly flexible multicast switching. The combination of the RLC, flexible multicast, and mobility prediction, makes the communication resilient to packet loss and helps to avoid handover failures of existing solutions while reducing overall packet delivery cost, hence offering sustainable mobility support. The performance of the proposed scheme is evaluated using a realistic vehicular mobility dataset and cellular network infrastructure and compared with Fast Handover for Proxy Mobile IPv6 (PFMIPv6). The results show that our scheme efficiently supports seamless session continuity in high mobility environments, reducing the total traffic delivery cost by 44% compared to its counterpart PFMIPv6, while reducing handover delay by 26% and handover failure to less than 2% of total handovers

Contributions to Vehicular Communications Systems and Schemes

La dernière décennie a marqué une grande hausse des applications véhiculaires comme une nouvelle source de revenus et un facteur de distinction dans l'industrie des véhicules. Ces applications véhiculaires sont classées en deux groupes : les applications de sécurité et les applications d'info divertissement. Le premier groupe inclue le changement intelligent de voie, l'avertissement de dangers de routes et la prévention coopérative de collision qui comprend la vidéo sur demande (VoD), la diffusion en direct, la diffusion de météo et de nouvelles et les jeux interactifs. Cependant, Il est à noter que d'une part, les applications véhiculaires d'info divertissement nécessitent une bande passante élevée et une latence relativement faible ; D'autre part, les applications de sécurité requièrent exigent un délai de bout en bout très bas et un canal de communication fiable pour la livraison des messages d'urgence. Pour satisfaire le besoin en applications efficaces, les fabricants de véhicules ainsi que la communauté académique ont introduit plusieurs applications à l’intérieur de véhicule et entre véhicule et véhicule (V2V). Sauf que, l'infrastructure du réseau sans fil n'a pas été conçue pour gérer les applications de véhicules, en raison de la haute mobilité des véhicules, de l'imprévisibilité du comportement des conducteurs et des modèles de trafic dynamiques. La relève est l'un des principaux défis des réseaux de véhicules, car la haute mobilité exige au réseau sans fil de faire la relève en un très court temps. De plus, l'imprévisibilité du comportement du conducteur cause l'échec des protocoles proactifs traditionnels de relève, car la prédiction du prochain routeur peut changer en fonction de la décision du conducteur. Aussi, le réseau de véhicules peut subir une mauvaise qualité de service dans les régions de relève en raison d'obstacles naturels, de véhicules de grande taille ou de mauvaises conditions météorologiques. Cette thèse se concentre sur la relève dans l'environnement des véhicules et son effet sur les applications véhiculaires. Nous proposons des solutions pratiques pour les réseaux actuellement déployés, principalement les réseaux LTE, l'infrastructure véhicule à véhicule (V2V) ainsi que les outils efficaces d’émulateurs de relèves dans les réseaux véhiculaires.----------ABSTRACT: The last decade marked the rise of vehicular applications as a new source of revenue and a key differentiator in the vehicular industry. Vehicular Applications are classified into safety and infotainment applications. The former include smart lane change, road hazard warning, and cooperative collision avoidance; however, the latter include Video on Demand (VoD), live streaming, weather and news broadcast, and interactive games. On one hand, infotainment vehicular applications require high bandwidth and relatively low latency; on the other hand, safety applications requires a very low end to end delay and a reliable communication channel to deliver emergency messages. To satisfy the thirst for practical applications, vehicle manufacturers along with research institutes introduced several in-vehicle and Vehicle to Vehicle (V2V) applications. However, the wireless network infrastructure was not designed to handle vehicular applications, due to the high mobility of vehicles, unpredictability of drivers’ behavior, and dynamic traffic patterns. Handoff is one of the main challenges of vehicular networks since the high mobility puts pressure on the wireless network to finish the handoff within a short period. Moreover, the unpredictability of driver behavior causes the traditional proactive handoff protocols to fail, since the prediction of the next router may change based on the driver’s decision. Moreover, the vehicular network may suffer from bad Quality of Service (QoS) in the regions of handoff due to natural obstacles, large vehicles, or weather conditions. This thesis focuses on the handoff on the vehicular environment and its effect on the vehicular applications. We consider practical solutions for the currently deployed networks mainly Long Term Evolution (LTE) networks, the Vehicle to Vehicle (V2V) infrastructure, and the tools that can be used effectively to emulate handoff on the vehicular networks