28 research outputs found

    Implementation and Performance Evaluation of an NGN prototype using WiMax as an Access Technology

    Get PDF
    Telecommunications networks have evolved to IP-based networks, commonly known as Next Generation Networks (NGN). The biggest challenge in providing high quality realtime multimedia applications is achieving a Quality of Service (QoS) consistent with user expectations. One of the key additional factors affecting QoS is the existence of different QoS mechanisms on the heterogeneous technologies used on NGN platforms. This research investigates the techniques used to achieve consistent QoS on network technologies that use different QoS techniques. Numerous proposals for solving the end-to-end QoS problem in IP networks have adopted policy-based management, use of signalling protocols for communicating applications QoS requirements across different Network Elements and QoS provisioning in Network Elements. Such solutions are dependent on the use of traffic classification and knowledge of the QoS requirements of applications and services on the networks. This research identifies the practical difficulties involved in meeting the QoS requirements of network traffic between WiMax and an IP core network. In the work, a solution based on the concept of class-of-service mapping is proposed. In the proposed solution, QoS is implemented on the two networks and the concept of class-of-service mapping is used to integrate the two QoS systems. This essentially provides consistent QoS to applications as they traverse the two network domains and hence meet end-user QoS expectations. The work is evaluated through a NGN prototype to determine the capabilities of the networks to deliver real-time media that meets user expectations

    Understanding the effectiveness of open standards for providing access to functions in next generation networks

    Full text link
    University of Technology, Sydney. Faculty of Engineering and Information Technology.The traditional telecommunications environment is 'closed', where applications can only be developed internally with specific knowledge of individual network technologies. In the last several years, there has been an enormous increase in efforts to 'open up ' these networks for application development, leading to open standards such as the Parlay/OSA APIs. This thesis is primarily concerned with understanding the effectiveness of open standards for providing third party stakeholders with access to functions in Next Generation Networks. Effectiveness in this context is to do with how well open systems may, and can, enable the business aims, and consequent technological advantages to achieve the business aims. We reason about the effectiveness from three perspectives in terms of whether the open standard provides sufficient openness, functional coverage, and practicality. While the methodology and models are applicable to evaluating open standards in general, we specifically apply them to the QoS control functionality provided by the Parlay/OSA Connectivity Manager Service Capability Feature

    Dependable IMS services - A Performance Analysis of Server Replication and Mid-Session Inter-Domain Handover

    Get PDF

    Optimização de recursos para difusão em redes de próxima geração

    Get PDF
    Doutoramento em ElectrotecniaEsta tese aborda o problema de optimização de recursos de rede, na entrega de Serviços de Comunicação em Grupo, em Redes de PrĂłxima Geração que suportem tecnologias de difusĂŁo. De acordo com esta problemĂĄtica, sĂŁo feitas propostas que levam em atenção a evolução espectĂĄvel das redes 3G em Redes HeterogĂ©neas de PrĂłxima Geração que incluam tecnologias de difusĂŁo tais como o DVB. A optimização de recursos em ComunicaçÔes em Grupo Ă© apresentada como um desafio vertical que deve cruzar diversas camadas. As optimizaçÔes aqui propostas cobrem tanto a interface entre Aplicação e a Plataforma de Serviços para a disponibilização de serviços de comunicação em grupo, como as abstracçÔes e mapeamentos feitos na interface entre a Rede Central e a Rede de Acesso RĂĄdio. As optimizaçÔes propostas nesta tese, assumem que o caminho evolutivo na direcção de uma Rede de PrĂłxima Geração Ă© feito atravĂ©s do IP. Em primeiro lugar sĂŁo endereçadas as optimizaçÔes entre a Aplicação e a Plataforma de Serviços que jĂĄ podem ser integradas nas redes 3G existentes. Estas optimizaçÔes podem potenciar o desenvolvimento de novas e inovadoras aplicaçÔes, que atravĂ©s do uso de mecanismos de distribuição em difusĂŁo podem fazer um uso mais eficiente dos recursos de rede. De seguida sĂŁo apresentadas optimizaçÔes ao nĂ­vel da interface entre a Rede Central e a Rede de Acesso RĂĄdio que abordam a heterogeneidade das redes futuras assim como a necessidade de suportar tecnologias de difusĂŁo. É ainda considerada a possibilidade de aumentar a qualidade de serviço de serviços de difusĂŁo atravĂ©s do mapeamento do IP multicast em portadoras unidireccionais. Por forma a validar todas estas optimizaçÔes, vĂĄrios protĂłtipos foram desenvolvidos com base num router avançado para redes de acesso de prĂłxima geração. As funcionalidades e arquitectura de software desse router sĂŁo tambĂ©m aqui apresentadas.This thesis addresses the problem of optimizing network resource usage, for the delivery of Group Services, in Next Generation Networks featuring broadcast technologies. In this scope, proposals are made according to the expected evolution of 3G networks into Next Generation Heterogeneous Networks that include broadcast technologies such as DVB. Group Communication resource optimization is considered a vertical challenge that must cross several layers. The optimizations here proposed cover both Application to Service Platform interfaces for group communication services, and Core Network to Radio Access Network interface abstractions and mappings. The proposed optimizations are also presented taking into consideration network evolution path towards an All-IP based Next Generation Network. First it is addressed the Application to Service Platform optimization, which can already be deployed over 3G networks. This optimization could potentiate the development of new and innovative applications that through the use of broadcast/multicast service delivery mechanisms could be more efficient network wise. Next proposals are made on the Core Network to Radio Access Network interfaces that address the heterogeneity of future networks and consider the need to support broadcast networks. It is also considered the possibility to increase the Quality of Service of broadcast/multicast services based on the dynamic mapping of IP multicast into unicast radio bearers. In order to validate these optimizations, several prototypes were built based on an advanced access router for next generation networks. Such access router functionalities and software architecture are also presented here

    Inter-domain interoperability framework based on WebRTC

    Get PDF
    Nowadays, the communications paradigm is changing with the convergence of communication services to a model based on IP networks. Applications such as messaging or voice over IP are increasing its popularity and Communication Service Providers are focusing on offering this kind of services. Moreover, Web Real Time Communication (WebRTC) has emerged as a technology that eases the creation of web applications featuring Real-Time Communications over IP networks without the need to develop and install any plug-in. It lacks of specifications in the control plane, leaving the possibility to use WebRTC over tailored web signalling solutions or legacy networks such as IP Multimedia Subsystem (IMS). This technology brings a wide range of possibilities for web developers, but Communication Service Providers are adviced to develop solutions based on the WebRTC technology as described in the Eurescom Study P2252. The lack of WebRTC specifications on the signalling platform together with the threats and opportunities that this technology represents for Communication Service Providers, makes evident the need of research on interoperability solutions for the different kind of signalling implementations and experimentation on the best way for Communication Service Providers to obtain the maximum benefit from WebRTC technology. The main goal of this thesis is precisely to develop a WebRTC interoperability framework and perform experiments on whether the Communication Service Providers should use their existing IMS solutions or develop tailored web signalling platforms for WebRTC deployments. In particular, the work developed in this thesis was completed under the framework of the Webrtc interOperability tested in coNtradictive DEployment scenaRios (WONDER) experimentation for the OpenLab project. OpenLab is a Large-scale integrating project (IP) and is part of the European Union Framework Programme 7 for Research and Development (FP7) addressing the work programme topic Future Internet Research and Experimentation.Actualmente, el paradigma de comunicaciones estĂĄ cambiando gracias a la convergencia de los servicios de comunicaciones hacia un modelo basado en redes IP. Aplicaciones tales como la mensajerĂ­a y la voz sobre IP estĂĄn creciendo en popularidad mientras los proveedores de servicios de comunicaciones se centran en ofrecer este tipo de servicios basados en redes IP. Por otra parte, la tecnologĂ­a WebRTC ha surgido para facilitar la creaciĂłn de aplicaciones web que incluyan comunicaciones en tiempo real sobre redes IP sin la necesidad de desarrollar o instalar ningĂșn complemento. Esta tecnologĂ­a no especifica los protocolos o sistemas a utilizar en el plano de control, dejando a los desarrolladores la posibilidad de usar WebRTC sobre soluciones de señalizaci on web especĂ­ficas o utilizar las redes de señalizaciĂłn existentes, tales como IMS. WebRTC abre un gran abanico de posibilidades a los desarrolladores web, aunque tambiĂ©n se recomienda a los proveedores de servicios de comunicaciones que desarrollen soluciones basadas en WebRTC como se describe en el estudio P2252 de Eurescom. La falta de especificaciones en el plano de señalizaciĂłn junto a las oportunidades y amenazas que WebRTC representa para los proveedores de servicios de comunicaciones, hacen evidente la necesidad de investigar soluciones de interoperabilidad para las distintas implementaciones de las plataformas de señalizaciĂłn y de experimentar c omo los proveedores de servicios de comunicaciones pueden obtener el mĂĄximo provecho de la tecnologĂ­a WebRTC. El objetivo principal de este Proyecto Fin de Carrera es desarrollar un marco de interoperabilidad para WebRTC y realizar experimentos que permitan determinar bajo que condiciones los proveedores de servicios de comunicaciones deben utilizar las plataformas de se~nalizaci on existentes (en este caso IMS) o desarrollar plataformas de señalizaciĂłn a medida basadas en tecnologĂ­as web para sus despliegues de WebRTC. En particular, el trabajo realizado en este Proyecto Fin de Carrera se llevĂł a cabo bajo el marco del proyecto WONDER para el programa OpenLab. OpenLab es un proyecto de integraciĂłn a gran escala en el cual se desarrollan investigaciones y experimentos en el ĂĄmbito del futuro Internet y que forma parte del programa FP7 de la UniĂłn Europea.IngenierĂ­a de TelecomunicaciĂł

    Integrating Context-Awareness in the IP Multimedia Subsystem for Enhanced Session Control and Service Provisioning Capabilities

    Get PDF
    The 3GPP-defined IP Multimedia Subsystem (IMS) is becoming the de-facto standard for IP-based multimedia communication services. It consists of an overlay control and service layer that is deployed on top of IP-based mobile and fixed networks. This layer encompasses a set of common functions (e.g. session control functions allowing the initiation/modification/termination of sessions) and service logics that are needed for the seamless provisioning of IP multimedia services to users, via different access technologies. As it continues to evolve, the IMS still faces several challenges including: the enabling of innovative and personalized services that would appeal to users and increase network operators' revenues; its interaction with other types of networks (e.g. wireless sensor networks) as means to enhance its capabilities; and the support of advanced QoS schemes that would manage the network resources in an efficient and adaptive manner. The context-awareness concept, which comes from the pervasive computing field, signifies the ability to use situational information (or context) in support to operations and decision making and for the provision of relevant services to the user. Context-awareness is considered to enhance users' experience and is seen as an enabler to adaptability and service personalization - two capabilities that could play important roles in telecommunication environments. This thesis focuses on the introduction of the context-awareness technology in the IMS, as means to enhance its session control and service provisioning capabilities. It starts by presenting the necessary background information, followed by a derivation of requirements and a review of the related work. To ensure the availability of contextual information within the network, we then propose an architecture for context information acquisition and management in the IMS. This architecture leverages and extends the 3GPP presence framework. Building on the capabilities of this architecture, we demonstrate how the managed information could be integrated in IMS operations, at the control and service levels. Showcasing control level integration, we propose a novel context-aware call differentiation framework as means to offer enhanced QoS support (for sessions/calls) in IMS-based networks. This framework enables the differentiation between different categories of calls at the IMS session control level, via dynamic and adaptive resource allocation, in addition to supporting a specialized charging model. Furthermore, we also propose a framework for enhanced IMS emergency communication services. This framework addresses the limitations of existing IP-based emergency solutions, by offering three main improvements: a QoS-enhanced emergency service; a context-aware personalized emergency service; and a conferencing-enhanced emergency service. We demonstrate the use of context awareness at the IMS service level using two new context-aware IMS applications. Finally, to validate our solutions and evaluate their performance, we build various proof-of-concept prototypes and OPNET simulation model

    Provision of Quality of Service in IP-based Mobile Access Networks

    Get PDF

    Flexible cross layer optimization for fixed and mobile broadband telecommunication networks and beyond

    Get PDF
    In der heutigen Zeit, in der das Internet im Allgemeinen und Telekommunikationsnetze im Speziellen kritische Infrastrukturen erreicht haben, entstehen hohe Anforderungen und neue Herausforderungen an den Datentransport in Hinsicht auf Effizienz und FlexibilitĂ€t. Heutige Telekommunikationsnetze sind jedoch rigide und statisch konzipiert, was nur ein geringes Maß an FlexibilitĂ€t und AnpassungsfĂ€higkeit der Netze ermöglicht und darĂŒber hinaus nur im begrenzten Maße die Wichtigkeit von DatenflĂŒssen im wiederspiegelt. Diverse LösungsansĂ€tze zum kompletten Neuentwurf als auch zum evolutionĂ€ren Konzept des Internet wurden ausgearbeitet und spezifiziert, um diese neuartigen Anforderungen und Herausforderungen adĂ€quat zu adressieren. Einer dieser AnsĂ€tze ist das Cross Layer Optimierungs-Paradigma, welches eine bisher nicht mögliche direkte Kommunikation zwischen verteilten FunktionalitĂ€ten unterschiedlichen Typs ermöglicht, um ein höheres Maß an DienstgĂŒte zu erlangen. Ein wesentlicher Indikator, welcher die Relevanz dieses Ansatzes unterstreicht, zeichnet sich durch die Programmierbarkeit von NetzwerkfunktionalitĂ€ten aus, welche sich aus der Evolution von heutigen hin zu zukĂŒnftigen Netzen erkennen lĂ€sst. Dieses Konzept wird als ein vielversprechender Lösungsansatz fĂŒr Kontrollmechanismen von Diensten in zukĂŒnftigen Kernnetzwerken erachtet. Dennoch existiert zur Zeit der Entstehung dieser Doktorarbeit kein Ansatz zur Cross Layer Optimierung in Festnetz-und Mobilfunknetze, welcher der geforderten Effizienz und FlexibilitĂ€t gerecht wird. Die ĂŒbergeordnete Zielsetzung dieser Arbeit adressiert die Konzeptionierung, Entwicklung und Evaluierung eines Cross Layer Optimierungsansatzes fĂŒr Telekommunikationsnetze. Einen wesentlichen Schwerpunkt dieser Arbeit stellt die Definition einer theoretischen Konzeptionierung und deren praktischer Realisierung eines Systems zur Cross Layer Optimierung fĂŒr Telekommunikationsnetze dar. Die durch diese Doktorarbeit analysierten wissenschaftlichen Fragestellungen betreffen u.a. die Anwendbarkeit von Cross Layer OptimierungsansĂ€tzen auf Telekommunikationsnetzwerke; die Betrachtung neuartiger Anforderungen; existierende Konzepte, AnsĂ€tze und Lösungen; die Abdeckung neuer FunktionalitĂ€ten durch bereits existierende Lösungen; und letztendlich den erkennbaren Mehrwert des neu vorgeschlagenen Konzepts gegenĂŒber den bestehenden Lösungen. Die wissenschaftlichen BeitrĂ€ge dieser Doktorarbeit lassen sich grob durch vier SĂ€ulen skizzieren: Erstens werden der Stand der Wissenschaft und Technik analysiert und bewertet, Anforderungen erhoben und eine LĂŒckenanalyse vorgenommen. Zweitens werden Herausforderungen, Möglichkeiten, Limitierungen und Konzeptionierungsaspekte eines Modells zur Cross Layer Optimierung analysiert und evaluiert. Drittens wird ein konzeptionelles Modell - Generic Adaptive Resource Control (GARC) - spezifiziert, als Prototyp realisiert und ausgiebig validiert. Viertens werden theoretische und praktische BeitrĂ€ge dieser Doktorarbeit vertiefend analysiert und bewertet.As the telecommunication world moves towards a data-only network environment, signaling, voice and other data are similarly transported as Internet Protocol packets. New requirements, challenges and opportunities are bound to this transition and influence telecommunication architectures accordingly. In this time in which the Internet in general, and telecommunication networks in particular, have entered critical infrastructures and systems, it is of high importance to guarantee efficient and flexible data transport. A certain level of Quality-of-Service (QoS) for critical services is crucial even during overload situations in the access and core network, as these two are the bottlenecks in the network. However, the current telecommunication architecture is rigid and static, which offers very limited flexibility and adaptability. Several concepts on clean slate as well as evolutionary approaches have been proposed and defined in order to cope with these new challenges and requirements. One of these approaches is the Cross Layer Optimization paradigm. This concept omits the strict separation and isolation of the Application-, Control- and Network-Layers as it enables interaction and fosters Cross Layer Optimization among them. One indicator underlying this trend is the programmability of network functions, which emerges clearly during the telecommunication network evolution towards the Future Internet. The concept is regarded as one solution for service control in future mobile core networks. However, no standardized approach for Cross Layer signaling nor optimizations in between the individual layers have been standardized at the time this thesis was written. The main objective of this thesis is the design, implementation and evaluation of a Cross Layer Optimization concept on telecommunication networks. A major emphasis is given to the definition of a theoretical model and its practical realization through the implementation of a Cross Layer network resource optimization system for telecommunication systems. The key questions answered through this thesis are: in which way can the Cross Layer Optimization paradigm be applied on telecommunication networks; which new requirements arise; which of the required functionalities cannot be covered through existing solutions, what other conceptual approaches already exist and finally whether such a new concept is viable. The work presented in this thesis and its contributions can be summarized in four parts: First, a review of related work, a requirement analysis and a gap analysis were performed. Second, challenges, limitations, opportunities and design aspects for specifying an optimization model between application and network layer were formulated. Third, a conceptual model - Generic Adaptive Resource Control (GARC) - was specified and its prototypical implementation was realized. Fourth, the theoretical and practical thesis contributions was validated and evaluated

    Analyse et amélioration de la qualité de services WEB multimédia et leurs mises en oeuvre sur ordinateur et sur FPGA

    Get PDF
    RĂ©sumĂ© : Les services Web, issus de l’avancée technologique dans le domaine des réseaux informatiques et des dispositifs de télécommunications portables et fixes, occupent une place primordiale dans la vie quotidienne des gens. La demande croissante sur des services Web multimédia (SWM), en particulier, augmente la charge sur les réseaux d’Internet, les fournisseurs de services et les serveurs Web. Cette charge est essentiellement due au fait que les SWM de haute qualité nécessitent des débits de transfert et des tailles de paquets importants. La qualité de service (par définition, telle que vue par l’utilisateur) est influencée par plusieurs facteurs de performance, comme le temps de traitement, le délai de propagation, le temps de réponse, la résolution d’images et l’efficacité de compression. Le travail décrit dans cette thèse est motivé par la demande continuellement croissante de nouveaux SWM et le besoin de maintenir et d’améliorer la qualité de ces services. Nous nous intéressons tout d’abord à la qualité de services (QdS) des SWM lorsqu’ils sont mis en Ɠuvre sur des ordinateurs, tels que les ordinateurs de bureau ou les portables. Nous commençons par étudier les aspects de compatibilité afin d’obtenir des SWM fonctionnant de manière satisfaisante sur différentes plate-formes. Nous étudions ensuite la QdS des SWM lorsqu’ils sont mis en Ɠuvre selon deux approches différentes, soit le protocole SOAP et le style RESTful. Nous étudions plus particulièrement le taux de compression qui est un des facteurs influençant la QdS. Après avoir considéré sous différents angles les SWM avec mise en Ɠuvre sur des ordinateurs, nous nous intéressons à la QdS des SWM lorsqu’ils sont mis en Ɠuvre sur FPGA. Nous effectuons alors une étude et une mise en Ɠuvre qui permet d’identifier les avantages à mettre en Ɠuvre des SWM sur FPGA. Les contributions se définissent en cinq volets comme suit : 1. Nous introduisons des méthodes de création, c’est-à-dire conception et mise en Ɠuvre, de SWM sur des plate-formes logicielles hétérogènes dans différents environnements tels que Windows, OS X et Solaris. Un objectif que nous visons est de proposer une approche permettant d’ajouter de nouveaux SWM tout en garantissant la compatibilité entre les plate-formes, dans le sens où nous identifions les options nous permettant d’offrir un ensemble riche et varié de SWM pouvant fonctionner sur les différentes plate-formes. 2. Nous identifions une liste de paramètres pertinents influençant la QdS des SWM mis en Ɠuvre selon le protocole SOAP et selon le style REST. 3. Nous développons un environnement d’analyse pour quantifier les impacts de chaque paramètre identifié sur la QdS de SWM. Pour cela, nous considérons les SWM mis en Ɠuvre selon le protocole SOAP et aussi selon style REST. Les QdS obtenues avec SOAP et REST sont comparées objectivement. Pour faciliter la comparaison, la même gamme d’images (dans l’analyse de SWM SOAP) a été réutilisée et les mêmes plate-formes logicielles. 4. Nous développons une procédure d’analyse qui permet de déterminer une corrélation entre la dimension d’une image et le taux de compression adéquat. Les résultats obtenus confirment cette contribution propre à cette thèse qui confirme que le taux de compression peut être optimisé lorsque les dimensions de l’image ont la propriété suivante : le rapport entre la longueur et la largeur est égal au nombre d’or connu dans la nature. Trois libraires ont été utilisées à savoir JPEG, JPEG2000 et DjVu. 5. Dans un volet complémentaire aux quatre volets précédents, qui concernent les SWM sur ordinateurs, nous étudions ainsi la conception et la mise en Ɠuvre de SWM sur FPGA. Nous justifions l’option de FPGA en identifiant ses avantages par rapport à deux autres options : ordinateurs et ASICs. Afin de confirmer plusieurs avantages identifiés, un SWM de QdS élevée et de haute performance est créé sur FPGA, en utilisant des outils de conception gratuits, du code ouvert (open-source) et une méthode fondée uniquement sur HDL. Notre approche facilitera l’ajout d’autres modules de gestions et d’orchestration de SWM. 6. La mise à jour et l’adaptation du code open-source et de la documentation du module Ethernet IP Core pour la communication entre le FPGA et le port Ethernet sur la carte Nexys3. Ceci a pour effet de faciliter la mise en Ɠuvre de SWM sur la carte Nexys3. // Abstract : Web services, which are the outcome of the technological advancements in IT networks and hand-held mobile devices for telecommunications, occupy an important role in our daily life. The increasing demand on multimedia Web services (MWS), in particular, augments the load on the Internet, on service providers and Web servers. This load is mainly due to the fact that the high-quality multimedia Web services necessitate high data transfer rates and considerable payload sizes. The quality of service (QoS, by definition as it is perceived by the user) is influenced by several factors, such as processing time, propagation delay, response time, image resolution and compression efficacy. The research work in this thesis is motivated by the persistent demand on new MWS, and the need to maintain and improve the QoS. Firstly, we focus on the QoS of MWS when they are implemented on desktop and laptop computers. We start with studying the compatibility aspects in order to obtain MWS functioning satisfactorily on different platforms. Secondly, we study the QoS for MWS implemented according to the SOAP protocol and the RESTful style. In particular, we study the compression rate, which is one of the pertinent factors influencing the QoS. Thirdly, after the study of MWS when implemented on computers, we proceed with the study of QoS of MWS when implemented on hardware, in particular on FPGAs. We achieved thus comprehensive study and implementations that show and compare the advantages of MWS on FPGAs. The contributions of this thesis can be resumed as follows: 1. We introduce methods of design and implementation of MWS on heterogeneous platforms, such as Windows, OS X and Solaris. One of our objectives is to propose an approach that facilitates the integration of new MWS while assuring the compatibility amongst involved platforms. This means that we identify the options that enable offering a set of rich and various MWS that can run on different platforms. 2. We determine a list of relevant parameters that influence the QoS of MWS. 3. We build an analysis environment that quantifies the impact of each parameter on the QoS of MWS implemented on both SOAP protocol and RESTful style. Both QoS for SOAP and REST are objectively compared. The analysis has been held on a large scale of different images, which produces a realistic point of view describing the behaviour of real MWS. 4. We develop an analysis procedure to determine the correlation between the aspect ratio of an image and its compression ratio. Our results confirm that the compression ratio can be improved and optimised when the aspect ratio of iiiiv an image is close to the golden ratio, which exists in nature. Three libraries of compression schemes have been used, namely: JPEG, JPEG2000 and DjVu. 5. Complementary to the four contributions mentioned above, which concern the MWS on computers, we study also the design and implementation of MWS on FPGA. This is justified by the numerous advantages that are offered by FPGAs, compared to the other technologies such as computers and ASICs. In order to highlight the advantages of implementing MWS on FPGA, we developed on FPGA a MWS of high performance and high level of QoS. To achieve our goal, we utilised freely available design utilities, open-source code and a method based only on HDL. This approach is adequate for future extensions and add-on modules for MWS orchestration
    corecore