Cette thèse est dédiée à l'étude de la mobilité et de la qualité de service (QoS) sur les réseaux locaux sans-fil (WLANs). Nous affirmons que plusieurs conditions doivent être satisfaites afin de pouvoir donner des garanties de QoS sur des réseaux locaux sans-fil. Nous proposons que les WLANs adoptent un modèle de QoS basé sur des garanties statistiques, tel que le modèle Diffserv de l'IETF. Le protocole Mobile IP, ainsi que d'autres mécanismes de gestion de la mobilité ne sont pas adaptés pour gérer la mobilité dans des régions limitées géographiquement. Pour cela, nous proposons une approche basée sur le modèle de la micro-mobilité pour assurer la gestion de la mobilité. De même, nous proposons une architecture qui intègre la gestion de la mobilité et de la QoS. Il s'agit d'une architecture hiérarchique qui couple notre protocole de mobilité avec un protocole de signalisation dans la bande (in-band) qui permet la gestion de la QoS. Le mémoire présente d'abord l'état de l'art dans les domaines des WLANs, la mobilité IP, et la QoS sur IP. Ensuite, nous présentons et discutons nos propositions pour la gestion de la QoS et de la mobilité sur les réseaux locaux. De même, nous présentons l'implémentation de prototypes de nos propositions et l'évaluation de leurs performances. Nous concluons par la présentation de nos contributions et des perspectives envisagées.

<p>The company Västra Mälardalens Kommunalförbund, VMKF, wishes to revise and optimize their present data and IP-telephony network as of today consists of the three municipalities Köping, Arboga and Kungsör. As a municipal corporation, they seek consultation regarding internal as well as external review and investigation of the main structure of the network, its functionality and safety. By today’s increasing demands of Internet accessibility, availability of services and security far more extends the requirement of a complete network design. The foundation of networking rests on the balance between each of these necessities. Therefore, it is of grave importance to optimize a network design, use of hardware and to minimize the administrative overhead. In particular, when the municipality is short of resources and time means money. By letting an impartial investigation of the network act as a starting point it was established that several improvement could be applied. Among these a reconstructed and improved network topology that includes subjects as routing, switching, safety and security, quality of service and technical administrative overhead and the implementation of a real time monitoring of network bandwidth consumption.</p> / <p>Företaget Västra Mälardalens Kommunalförbund, VMKF, har önskemål om att granska och optimera deras befintliga data- och IP-telefoninätverk som i dagsläget spänner över de tre kommunerna Köping, Arboga och Kungsör. Som ett kommunalägt företag önskar de konsultation rörande intern såväl som extern granskning och optimering av huvuddelen av nätverkets funktionalitet samt säkerhet. I och med dagens ökade Internetanvändning och funktionalitetsbehov ställs allt högre krav på tillgänglighet, säkerhet och användarvänlighet. Nätverksteknik bygger mycket på balansen mellan dessa tre punkter. Därför gäller det att optimera nätverkets design, hårdvaruanvändning och att minimera administrativa laster. Detta i synnerhet då kommunens resurser är knappa och då tid i dagens samhälle innebär pengar. Genom att låta en granskning över nätverket som det ser ut i dag ligga till grund konstaterades att flertalet förbättringsmöjligheter kunde genomföras. Bland dessa återfinns en omstrukturerad nätverksdesign som innefattar routing, switching, säkerhet, QoS och teknisk administration samt implementeringen av en realtidsövervakning av bandbreddsanvändning.</p>

<p>Multi-Protocol Label Switching (MPLS) is a technique that can be used to improve the performance of a computer communication network. By use of MPLS, data packets can be switched on the basis of labels rather than routed on the basis of destination address. MPLS supports different features like QoS, traffic engineering and VPNs etc.</p><p>This thesis evaluates the working and performance of MPLS and its support for Quality of Service. QoS is required in the network when real time traffic is transported.</p><p>In this thesis it is described, how QoS guarantees are assigned to the IP packets and how MPLS QoS environment differs from the traditional IP routing environment. MPLS QoS works as the IP QoS, but MPLS QoS enhances the capability of network as compared to the IP QoS based network.</p><p>The thesis studies the use of MPLS in an integrated environment with DiffServ QoS model and also implements MPLS QoS in a Lab environment to compare MPLS QoS with IP QoS. Real time traffic faces longer delays in IP QoS based networks. MPLS QoS reduces the delays in real time traffic transmission.</p><p>The study results and the practical implementations show that MPLS QoS provide much better results than simple IP QoS.</p>

<p>In future mobile networks service quality might be poor. A new measure is needed to be able to assess services in terms of their effectiveness and usefulness despite their lacking visual appeal. Cognitive Quality of Service is a way to measure the effectiveness in use of a networked service.</p><p>This thesis introduces Cognitive Quality of Service and puts it in relation to other ways to measure quality in streaming media. Through four studies the concept is used to improve multicast performance in a WLAN, to assess the effectiveness of simple animations compared to video, to build an application that fuses video and animations and to assess the differences between various levels of streaming video quality.</p><p>Guidelines on how to measure Cognitive Quality of Service are introduced based on a review of available literature and later analyzed in light of the studies presented in the thesis. It turns out that the guidelines are sound and should be used as a basis for assessing Cognitive Quality of Service.</p><p>Finally, the usefullness of Cognitive Quality of Service is analyzed. It turns out that it is especially useful when comparing different media, e.g. animations and video. In the video only case even bit-rate might be a useful predictor of subjective quality.</p> / <p>I framtiden kommer användare att titta på videosekvenser i trådlösa apparater, exempelvis mobiltelefoner. På grund av tekniska faktorer som störningar och på grund av kostnaden för det kommer den kvalitet som de erhåller inte att vara jämförbar med till exempel den kvalitet som kan erhållas när man tittar på tv. Trots det kan man anta att sådan video kan vara intressant och upplysande.</p><p>I avhandlingen introduceras och används begreppet Cognitive Quality of Service (CQoS) - kognitiv servicekvalitet. Begreppet definieras av att den överföring som ger den bästa förståelsen och känslomässiga reaktionen också har bäst CQoS. För att mäta CQoS bör man följa vissa riktlinjer, särskilt som det är svårt att mäta förståelse i samband med att man tittar på video.</p><p>Författaren har tillsammans med medarbetare tittat på hur man kan förbättra förhållandena för själva radioöverföringen (studie I). Genom en algoritm som ger multicast-paket bättre skydd mot kollisioner visas att man kan erhålla förbättrad överföringskapacitet för strömmande video i ett trådlöst nätverk.</p><p>Animeringar är ett alternativ till video som kräver låg bandbredd. I ett experiment har man undersökt hur väl animeringar står sig mot video av olika kvalitet när det gäller att upplysa användaren och ge en bra upplevelse (studie II). Det visade sig att animeringar var bättre för förståelsen medan video gav en bättre känslomässig upplevelse. Vanare åskådare föredrog videon medan ovanare åskådare föredrog animeringarna.</p><p>Frågan som ställdes var då hur man kunde kombinera respektive mediums fördelar för att få en så bra blandning som möjligt. Å ena sidan var animeringarna billiga och lätta att förstå medan videon var dyrare och mer intressant. Ett prototypgränssnitt skapades. Där kunde användaren själv välja vilken mix mellan de två alternativen som skulle visas (studie III). Det visade sig att försökspanelen föredrog video och dessutom ville ha mer information om spelare och match.</p><p>Trots animationernas förträfflighet kan man anta att det ändå är video som kommer att dominera i framtiden. En sista studie genomfördes för att se om man kunde finna liknande resultat vid olika kvalitetsgrader i video som man tidigare hade funnit mellan video och animeringar (studie IV). Det visade sig att så länge man höll sig till ett format var sambanden enklare. Mer var helt enkelt bättre upp till en viss gräns där det inte tillförde mer att öka överföringsresurserna för videon.</p><p>Sammanfattningsvis visar studierna att CQoS kan ge värdefull designkunskap. I synnerhet när man jämför olika presentationsformer som i det här fallet animeringar och video. Nästa steg blir att gå vidare med att applicera CQoS i tvåvägskommunikation, särskilt i Conversational Multimedia (CMM)– ungefär bildtelefoni – där det är särskilt goda möjligheter att sammanställa en för omständigheterna anpassad mediamix.</p>

隨著全球通訊技術的發展，第四代行動通訊系統(4G)已進入我們的生活之中。其中又以長期演進技術（Long Term Evolution, LTE）為代表。LTE使用了正交分頻多工(Orthogonal Frequency-Division Multiplexing, OFDM)以及多輸入多輸出(Multi-Input Multi-Output, MIMO)技術，使得第四代行動網路在上傳以及下載時，能擁有更大的傳輸量，及更遠的傳輸距離。 　　當下載時，因為每位使用者所在的環境不同，造成傳輸量、延遲時間因而不同，所以基地台分配資源時，尚有許多改善的空間。目前，許多文獻在探討如何公平且有效地分配資源塊(Resource Block, RB)給使用者裝置(User Equipment, UE)，如Proportional Fair (PF)與Modified Largest Weighted Delay First (MLWDF)兩種排程機制。前者考量了優先權的公平性，但沒有考量服務品質(Quality of Service, QoS)；後者對於較即時的封包有較高的優先權，卻導致資源分配不均，將大量的資源給部份使用者。本篇論文著重於公平性以及服務品質的考量，使用不同方式的佇列存放各種不同的資源型態(resource type)，依照資源型態佔整體資源數量的比例，以及計算出Adaptive Modified Largest Weighted Delay First (AMLWDF)的優先權值，針對各個UE與各個通道(channel)做全面性地配置，來提昇公平性及降低延遲以符合QoS要求。 / Owing to the development of global communication technology, the Long Term Evolution (LTE) is the latest technology for the fourth generation mobile communication systems (4G) that has entered into our lives. LTE uses Orthogonal Frequency Division Multiplexing (OFDM) and Multiple-Input Multiple-Output (MIMO) technology to provide high data rate transmission and long distance transmission when users doing download and upload. When doing download, users may have different throughput, delay time, and jitter due to they are in different locations. To improve these performance indexes, the E-UTRAN Node B (eNodeB) has to allocate resource blocks efficiently. In the literature, many works explore how to fairly allocate resource blocks (RB) to users. Proportional Fair (PF) and Modified Largest Weighted Delay First (MLWDF) are two example scheduling mechanisms. PF considers service priority and fairness, but doesn't consider the Quality of Service (QoS). MLWDF considers QoS but not service priority and fairness, and allows eNodeB giving more resources to particular users. In this thesis, we focus on resource allocation problem of downlink scheduling in LTE. Considering fairness and QoS, we store various resource types into particular queues and calculate the priorities using Adaptive Modified Largest Weighted Delay First (AMLWDF). The relationships between users and channels are coordinated according to the priorities for the sake of enhancing the fairness and reducing the delay time and jitter.

In mobile and wireless networks, data broadcasting for popular data items enables the efficient utilization of the limited wireless bandwidth. However, efficient data scheduling schemes are needed to fully exploit the benefits of data broadcasting. Towards this goal, several broadcast scheduling policies have been proposed. These existing schemes have mostly focused on either minimizing response time, or drop rate, when requests are associated with hard deadlines. The inherent inaccuracy of hard deadlines in a dynamic mobile environment motivated us to use Service Level Agreements (SLAs) where a user specifies the utility of data as a function of its arrival time. Moreover, SLAs provide the mobile user with an already familiar quality of service specification from wired environments. Hence, in this dissertation, we propose SAAB, an SLA-aware adaptive data broadcast scheduling policy for maximizing the system utility under SLA-based performance measures. To achieve this goal, SAAB considers both the characteristics of disseminated data objects as well as the SLAs associated with them. Additionally, SAAB automatically adjusts to the system workload conditions which enables it to constantly outperform existing broadcast scheduling policies.

Home networks are evolving vigorously and are also becoming more and more heterogeneous and complex. Home networks contain new services and numerous devices with wired and wireless links. At the same time, users demand high levels of quality of service for many new applications. Hence, the supervision of links quality tends to be mandatory in emergent home networks, to trigger QoS mechanisms. In this context, this dissertation proposes the utilization of the available bandwidth as a performance indicator in hybrid home networks (e.g. for remote service-evaluation, diagnosis and fault detection) and as link-state metric for a number of QoS mechanisms (e.g., admission control, path selection and load balancing). In this dissertation, we firstly explain why available bandwidth probing is a fundamental tool in the new QoS architectures for hybrid home networks and we explore different use cases. We investigate the networking constraints that affect bandwidth probing in hybrid home networks. We explain why most tools to measure available bandwidth on Internet paths are not very efficient on home networks. We make a taxonomic study of a number of state-of-the-art probing techniques and probing tools for available bandwidth. At that aim, we propose a functional framework, called Metrics Profile Capture Filter and Feedback (MPCFF). Based on these studies, we choose Iperf in TCP mode as an attractive tool to estimate available bandwidth. Then, we conduct a performance evaluation on an experimental test bed, to compare Iperf in lightweight TCP-mode vs. various state-of-the-art tools (Wbest, Pathchirp, Pathload and IGI/PTR). We show that Iperf in lightweight TCP mode is superior in terms of accuracy and speed of convergence. Finally, we integrate Iperf in lightweight TCP mode into a path selection protocol using the Inter-MAC software (developed in the Omega European project). We show, on a test bed, how Iperf in lightweight TCP mode enhances the Inter-MAC path selection by eliminating performance deterioration due to time-varying capacity links. Our results show that Iperf in lightweight TCP mode, accurately, triggers path selection and load balancing mechanisms, to adapt the network resources to the strong degradation of WiFi and PLC links. Available bandwidth probing detects and helps to control real-time deviations of the quality of experience, associated of sensitive applications. At the same time, available-bandwidth probing helps the service provider to isolate failures and to monitor the end-to-end residential service, on demand or on long-term periodicity basis.

In mobile and wireless networks, data broadcasting for popular data items enables the efficient utilization of the limited wireless bandwidth. However, efficient data scheduling schemes are needed to fully exploit the benefits of data broadcasting. Towards this goal, several broadcast scheduling policies have been proposed. These existing schemes have mostly focused on either minimizing response time, or drop rate, when requests are associated with hard deadlines. The inherent inaccuracy of hard deadlines in a dynamic mobile environment motivated us to use Service Level Agreements (SLAs) where a user specifies the utility of data as a function of its arrival time. Moreover, SLAs provide the mobile user with an already familiar quality of service specification from wired environments. Hence, in this dissertation, we propose SAAB, an SLA-aware adaptive data broadcast scheduling policy for maximizing the system utility under SLA-based performance measures. To achieve this goal, SAAB considers both the characteristics of disseminated data objects as well as the SLAs associated with them. Additionally, SAAB automatically adjusts to the system workload conditions which enables it to constantly outperform existing broadcast scheduling policies.

La comunicación entre redes ad hoc y redes basadas en infraestructura resulta esencial para poder extender Internet más allá de su alcance tradicional, a aquellas áreas hasta ahora inaccesibles, permitiendo la utilización de servicios Web y otras muchas aplicaciones en todo momento y lugar.En esta tesis doctoral se abordan dos difíciles retos: intentar proporcionar calidad de servicio extremo a extremo en la comunicación entre una red ad hoc y una red fija, y alargar la supervivencia de la red ad hoc para que dicha comunicación sea lo más estable y duradera posible.Para lograr alcanzar estos objetivos, se ha realizado primeramente un estudio exhaustivo tanto de los modelos de calidad de servicio como de los protocolos de encaminamiento existentes para redes ad hoc aisladas. Fruto de dicho estudio ha surgido una primera contribución que consiste en el diseño e implementación de un protocolo de encaminamiento para la mejora de la supervivencia en una red ad hoc aislada.A partir de esta base se ha podido abordar la diferenciación de servicios en redes ad hoc conectadas con redes fijas; como consecuencia de esta investigación se ha desarrollado una segunda contribución que consiste en el diseño y evaluación de un modelo de diferenciación de servicios que se basa en la cooperación para el mantenimiento de la calidad de servicio entre ambas redes.Finalmente, mediante una tercera contribución, se ha conseguido mejorar la supervivencia de una red ad hoc conectada a una red basada en infraestructura con el diseño e implementación de un protocolo de encaminamiento específicamente creado para tal efecto. Además, se ha demostrado que la incorporación de este protocolo de encaminamiento en una red ad hoc que utiliza un modelo de calidad de servicio basado en la interacción entre la red ad hoc y la red IP fija, no sólo alarga la supervivencia de la red ad hoc sino que además evita un aumento de la congestión y mejora la diferenciación de servicios entre ambas redes.Las simulaciones exhaustivas realizadas sirven para comparar todas estas contribuciones con otras propuestas anteriores, demostrando su efectividad y rendimiento.Las contribuciones presentadas en esta tesis doctoral tienen una singular importancia, pues hasta la fecha no se ha desarrollado ningún modelo de calidad de servicio que permita la interacción y favorezca la cooperación entre una red ad hoc y una red IP fija con el fin de proporcionar calidad de servicio extremo a extremo. Las contribuciones que se aportan demuestran que sí que es posible la diferenciación de servicios entre una red ad hoc y una red IP fija; además, prueban que resulta imprescindible la cooperación e integración de los modelos de calidad de servicio de ambas redes para lograrlo. Este trabajo resulta pionero en estos aspectos y sirve para abrir una nueva línea de investigación con el fin de promover la comunicación entre redes ad hoc y redes fijas. / The communication between wireless ad hoc networks and infrastructure-based networks is essential to extend Internet beyond its traditional scope, to remote inaccessible areas, making Web services available anytime, anywhere.In this PhD thesis two difficult challenges are tackled: to provide end-to-end quality of service in the communication between an ad-hoc and a wired network, and to extend the ad-hoc network survivability to achieve that this communication becomes as stable and lasting as possible.In order to attain these goals, we have firstly done an exhaustive study of the existing quality of service models as well as the routing protocols for isolated ad hoc networks. A first contribution has arisen from this study that is based on the design and implementation of a routing protocol for improving the survivability in an isolated ad hoc network.Under this basis research has been carried out into service differentiation in ad hoc networks connected to fixed networks; as a consequence of this research we have developed the second contribution of this thesis, that consists of the design and evaluation of a service differentiation model based on the cooperation for the quality of service provision between both networks.Finally, by means of a third contribution, we have managed to improve the network survivability of an ad hoc network connected to an infrastructure-based network with the design and implementation of a routing protocol specifically created for this purpose. In addition, we have proved that the incorporation of this routing protocol to an ad hoc network that uses a quality of service model based on the interaction between the ad hoc and the fixed IP network, does not only extend the ad hoc network survivability, but it also avoids congestion increase and improves the service differentiation between both networks.Extensive simulations have been carried out to compare all these contributions with already existing ones, proving their effectiveness and performance.The present contributions in this PhD thesis have a singular importance, since no quality of service model has been developed that enables the interaction and favours the cooperation between an ad-hoc and a fixed IP network with the aim of providing end-to-end quality of service. The contributions demonstrate that it is really possible to differentiate services between an ad hoc and a fixed IP network; moreover, they show that the cooperation and integration of the quality of service models in both networks is unvaluable in order to achieve it. This is a pioneering work in these aspects and it will be very useful to open a new research line with the aim of promoting the communication between ad hoc networks and fixed networks.

The company Västra Mälardalens Kommunalförbund, VMKF, wishes to revise and optimize their present data and IP-telephony network as of today consists of the three municipalities Köping, Arboga and Kungsör. As a municipal corporation, they seek consultation regarding internal as well as external review and investigation of the main structure of the network, its functionality and safety. By today’s increasing demands of Internet accessibility, availability of services and security far more extends the requirement of a complete network design. The foundation of networking rests on the balance between each of these necessities. Therefore, it is of grave importance to optimize a network design, use of hardware and to minimize the administrative overhead. In particular, when the municipality is short of resources and time means money. By letting an impartial investigation of the network act as a starting point it was established that several improvement could be applied. Among these a reconstructed and improved network topology that includes subjects as routing, switching, safety and security, quality of service and technical administrative overhead and the implementation of a real time monitoring of network bandwidth consumption. / Företaget Västra Mälardalens Kommunalförbund, VMKF, har önskemål om att granska och optimera deras befintliga data- och IP-telefoninätverk som i dagsläget spänner över de tre kommunerna Köping, Arboga och Kungsör. Som ett kommunalägt företag önskar de konsultation rörande intern såväl som extern granskning och optimering av huvuddelen av nätverkets funktionalitet samt säkerhet. I och med dagens ökade Internetanvändning och funktionalitetsbehov ställs allt högre krav på tillgänglighet, säkerhet och användarvänlighet. Nätverksteknik bygger mycket på balansen mellan dessa tre punkter. Därför gäller det att optimera nätverkets design, hårdvaruanvändning och att minimera administrativa laster. Detta i synnerhet då kommunens resurser är knappa och då tid i dagens samhälle innebär pengar. Genom att låta en granskning över nätverket som det ser ut i dag ligga till grund konstaterades att flertalet förbättringsmöjligheter kunde genomföras. Bland dessa återfinns en omstrukturerad nätverksdesign som innefattar routing, switching, säkerhet, QoS och teknisk administration samt implementeringen av en realtidsövervakning av bandbreddsanvändning.