A micro-mobility solution for supporting QoS in global mobility

Today, users want to have simultaneously mobility, Quality of Service (QoS) and be always connected to Internet. Therefore, this paper proposes a QoS micro-mobility solution able to provide QoS support for global mobility. The solution comprises enhancements in the mobility management of Mobile IPv6 (MIPv6) and in the resources management of Differentiated Services (DiffServ) QoS model. The mobility management of MIPv6 was extended with fast and local handovers to improve its efficiency in micro-mobility scenarios with frequent handovers. The DiffServ resource management has been extended with adaptive and dynamic QoS provisioning to improve resources utilization in mobile IP networks. Further, in order to improve resources utilization the mobility and QoS messages were coupled, providing a resource management able to, proactively, react to mobile events. The performance improvement of the proposed solution and the model parametrization was evaluated using a simulation model. 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, keeps up unchangeable with MN mobility.(undefined

A QoS-enable solution for mobile environments

This paper addresses the problem of designing a suitable Quality of Service (QoS) solution for mobile environments. The proposed solution deploys a dynamic QoS provisioning scheme able to deal with service protection during node mobility within a local domain, presenting extensions to deal with global mobility. The dynamic QoS provisioning encompasses a QoS architecture that uses explicit and implicit setup mechanisms to request resources from the network for the purpose of supporting control plane functions and optimizing resource allocation. Abstract--- For efficient resource allocation, the resource and mobility management schemes have been coupled resulting in a QoS/Mobility aware network architecture able to react proactively to mobility events. Both management schemes have been optimized to work together, in order to support seamless handovers for mobile users running real-time applications. Abstract--- The analysis of performance improvement and the model parametrization of the proposed solution have been evaluated using simulation. Simulation results show that the solution avoids network congestion and also the starvation of less priority DiffServ classes. Moreover, the results also show that bandwidth utilization for priority classes is levered and that the QoS offered to Mobile Node's (MN's) applications, within each DiffServ class, is maintained in spite of MN mobility. Abstract--- The proposed model is simple, easy to implement and takes into account the mobile Internet requirements. Simulation results show that this new methodology is effective and able to provide QoS services adapted to application requests

Quality of service and mobility management in IP-based radio access networks

Master'sMASTER OF ENGINEERIN

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

Mobile Networks

The growth in the use of mobile networks has come mainly with the third generation systems and voice traffic. With the current third generation and the arrival of the 4G, the number of mobile users in the world will exceed the number of landlines users. Audio and video streaming have had a significant increase, parallel to the requirements of bandwidth and quality of service demanded by those applications. Mobile networks require that the applications and protocols that have worked successfully in fixed networks can be used with the same level of quality in mobile scenarios. Until the third generation of mobile networks, the need to ensure reliable handovers was still an important issue. On the eve of a new generation of access networks (4G) and increased connectivity between networks of different characteristics commonly called hybrid (satellite, ad-hoc, sensors, wired, WIMAX, LAN, etc.), it is necessary to transfer mechanisms of mobility to future generations of networks. In order to achieve this, it is essential to carry out a comprehensive evaluation of the performance of current protocols and the diverse topologies to suit the new mobility conditions

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 SUPPORT ARCHITECTURES FOR NEXT-GENERATION WIRELESS NETWORKS

With the convergence of the wireless networks and the Internet and the booming demand for multimedia applications, the next-generation (beyond the third generation, or B3G) wireless systems are expected to be all IP-based and provide real-time and non-real-time mobile services anywhere and anytime. Powerful and efficient mobility support is thus the key enabler to fulfil such an attractive vision by supporting various mobility scenarios. This thesis contributes to this interesting while challenging topic. After a literature review on mobility support architectures and protocols, the thesis starts presenting our contributions with a generic multi-layer mobility support framework, which provides a general approach to meet the challenges of handling comprehensive mobility issues. The cross-layer design methodology is introduced to coordinate the protocol layers for optimised system design. Particularly, a flexible and efficient cross-layer signalling scheme is proposed for interlayer interactions. The proposed generic framework is then narrowed down with several fundamental building blocks identified to be focused on as follows. As widely adopted, we assume that the IP-based access networks are organised into administrative domains, which are inter-connected through a global IP-based wired core network. For a mobile user who roams from one domain to another, macro (inter-domain) mobility management should be in place for global location tracking and effective handoff support for both real-time and non-real-lime applications. Mobile IP (MIP) and the Session Initiation Protocol (SIP) are being adopted as the two dominant standard-based macro-mobility architectures, each of which has mobility entities and messages in its own right. The work explores the joint optimisations and interactions of MIP and SIP when utilising the complementary power of both protocols. Two distinctive integrated MIP-SIP architectures are designed and evaluated, compared with their hybrid alternatives and other approaches. The overall analytical and simulation results shown significant performance improvements in terms of cost-efficiency, among other metrics. Subsequently, for the micro (intra-domain) mobility scenario where a mobile user moves across IP subnets within a domain, a micro mobility management architecture is needed to support fast handoffs and constrain signalling messaging loads incurred by intra-domain movements within the domain. The Hierarchical MIPv6 (HMIPv6) and the Fast Handovers for MIPv6 (FMIPv6) protocols are selected to fulfil the design requirements. The work proposes enhancements to these protocols and combines them in an optimised way. resulting in notably improved performances in contrast to a number of alternative approaches

Advance Reservations of Bandwidth in Computer Networks

In dieser Arbeit wurden die unterschiedlichen Aspekte untersucht, die die Leistungsfähigkeit eines Systems zur Vorausreservierung in Computer-Netzwerken bestimmen. Basierend auf einer Architektur, welche den Basisdienst für Vorausreservierungen mittels Multiprotocol Label Switching (MPLS) zur Verfügung stellt, wurden innerhalb eines Netzwerkmanagementsystems unterschiedliche Dienste implementiert und simulativ auf ihre Auswirkungen auf die Leistungsfähigkeit des Netzwerks in Bezug auf Anzahl zugelassener Datenströme sowie transportierte Datenmenge untersucht. Diese Dienste erweitern in entscheidendem Maße auch die Breite des Dienstangebots in Netzwerken im Vergleich zu bisherigen Implementierungen. So ist es möglich bei Angabe einer festen Datenmenge vom Netzwerkmanagement geeignete Übertragungszeiten und raten bestimmen zu lassen. Diese Parameter werden dann, zum Beispiel in Form von Service Level Agreements (SLA), vom Netzwerkmanagement garantiert und sind insbesondere in Umgebungen wichtig, in denen die Übertragung sehr großer Datenmengen notwendig ist, beispielsweise in Grid-Computing- Systemen. Die erweiterten Dienste dienen jedoch nicht nur den Nutzern, sondern sind auch für Betreiber interessant, da sie es ermöglichen die Leistungsfähigkeit des Netzwerkes zu erhöhen. Dies ist insbesondere zusammen mit weiteren Verfahren möglich, die die zusätzlich zur Verfügung stehenden Informationen über zeitliche Aspekte, wie die Dauer von Übertragungen, nutzen. Im Vergleich zu den heute hauptsächlich betrachteten Systemen zur sog. unmittelbaren Reservierung, kann bei geschicktem Einsatz der hier implementierten Dienste und Verfahren eine deutliche Verbesserung der Leistung erzielt werden. Hinzu kommen bei Vorausreservierungen die erheblichen Vorteile für die Nutzer eines Netzwerkes, wie z.B. der oben beschriebene Datentransfer. Die Leistung eines Netzwerkes bemisst sich jedoch nicht nur an der transportierten Datenmenge, sondern auch am Verhalten im Fehlerfall und der Geschwindigkeit des Managementsystems. Dazu wurden im Rahmen dieser Arbeit mögliche Strategien zur Reaktion von Vorausreservierungssystemen im Fall von Link-Ausfällen entwickelt und untersucht. Auch hier kommt dem zeitlichen Aspekt eine wichtige Bedeutung zu. Es erwies sich als erfolgreich, nicht nur unmittelbar betroffene Datenströme sondern auch solche, die zwar bereits bekannt, jedoch noch nicht aktiv waren, in die Fehlerbehandlungsstrategie mit einzubeziehen. Datenstrukturen, die von der Zugangskontrolle des Managementsystems benötigt werden und dort die Geschwindigkeit maßgeblich bestimmen, wurden unter den Aspekten der Zugriffsgeschwindigkeit und des Speicherverbrauchs untersucht. Hierbei wurde gezeigt, dass Arrays erhebliche Vorteile im Hinblick auf beide Aspekte haben und in den meisten Fällen einer Baumstruktur, die speziell für die Aufgabe innerhalb der Zugangskontrolle entwickelt wurde, überlegen sind. Die Nutzung von Vorausreservierungen in Computer-Netzwerken ist damit eine nützliche und wichtige Erweiterung der Funktionalität eines Netzwerkes sowohl in Bezug auf das zur Verfügung stehende Angebot an Diensten, als auch im Hinblick auf die Leistungsfähigkeit des Netzwerkes.In this thesis, the impact of using advance reservations of bandwidth in a computer network on the performance for both clients and operators of the network is examined. Based on an architecture that uses multi-protocol label switching (MPLS) controlled by bandwidth brokers, a number of services that - compared to todays best-effort or immediate reservation networks - provide an enhanced functionality for clients were developed. These services allow clients to specify requests in a less stringent way than currently necessary, for example, it is possible to define only the amount of data to be transmitted between two network endpoints and the management system then determines suitable transmission parameters such as start and stop time and transmission rate. This functionality provides reliable feedback to clients and can serve as a foundation for providing service-level agreements, e.g., guaranteeing deadlines for the transmission of a certain amount of data. The additional services can also be used by network operators to improve the overall utilization of the network. In addition, the various opportunities of using the additional temporal dimension of the advance reservation service are suitable to improve the network performance. It can be shown that the amount of blocked requests and bandwidth can be considerably decreased making use of both services and the additional information available in the given environment. Besides the achievable throughout and amount of admitted requests, the term performance in the context of advance reservation systems also covers other aspects such as failure recovery strategies and the processing time required by the network management system. In the thesis, several strategies to be applied in case of link failures are outlined and examined with respect to their applicability and achievable performance. For example, it can be shown that it is worthwhile to consider not only flows which are active at the time a failure occurs but also to take inactive but already admitted flows into account in order to achieve the best possible performance. In addition to failure recovery, also the processing speed of the management system is of importance. For that purpose, in particular the data structures used to store the current and future network status need to be examined since they dominate the processing time of the management system. Two data structures, arrays and a tree which was especially designed for this purpose were examined, showing that arrays are superior with respect to processing speed and memory consumption in almost any environment

QoS provisioning and mobility management for IP-based wireless LAN

Today two major technological forces drive the telecommunication era: the wireless cellular systems and the Internet. As these forces converge, the demand for new services, increasing bandwidth and ubiquitous connectivity continuously grows. The next-generation mobile systems will be based solely or in a large extent, on the Internet Protocol (IP). This thesis begins by addressing the problems and challenges faced in a multimedia, IP-based Wireless LAN environment. The ETSI HiperLAN/2 system has been mainly selected as the test wireless network for our theoretical and simulation experiments. Apart from the simulations, measurements have been taken from real life test scenarios, where the IEEE 802.11 system was used (UniS Test-bed). Furthermore, a brief overview of the All-IP network infrastructure is presented. An extension to the conventional wireless (cellular) architecture, which takes advantage of the IP network characteristics, is considered. Some of the trends driving the 3G and WLANs developments are explored, while the provision of quality of service on the latter for real-time and non-real-time multimedia services is investigated, simulated and evaluated. Finally, an efficient and catholic Q0S framework is proposed. At the same time, the multimedia services should be offered in a seamless and uninterrupted manner to users who access the all-IP infrastructure via a WLAN, meeting the demands of both enterprise and public environments anywhere and anytime. Thus providing support for mobile communications not only in terms of terminal mobility, as is currently the case, but also for session, service and personal mobility. Furthermore, this mobility should be available over heterogeneous networks, such as WLANs, IJMTS, as well as fixed networks. Therefore, this work investigates issues such as, multilayer and multi-protocol (SIP-Mobile IP-Cellular IP) mobility management in wireless LAN and 3G domains. Several local and global mobility protocols and architectures have been tested and evaluated and a complete mobility management framework is proposed. Moreover, integration of simple yet efficient authentication, accounting and authorisation mechanisms with the multimedia service architecture is an important issue of IP-based WLANs. Without such integration providers will not have the necessary means to control their provided services and make revenue from the users. The proposed AAA architecture should support a robust AAA infrastructure providing secure, fast and seamless access granting to multimedia services. On the other hand, a user wishing a service from the All-IP WLAN infrastructure needs to be authenticated twice, once to get access to the network and the other one should be granted for the required service. Hence, we provide insights into these issues by simulating and evaluating pre-authentication techniques and other network authentication scenarios based on the wellknown IEEE 802.lx protocol for multimedia IP-based WLANs.EThOS - Electronic Theses Online ServiceGBUnited Kingdo