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Wagh, Prasad J. "DiffServ overlay multicast for videoconferencing." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4301.
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Thesis (M.S.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 10 , 2007) Includes bibliographical references.
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NASCIMENTO, KIUZA FRAGA. "TRAFFIC MARKING IN DIFFSERV NETWORKS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5751@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOA crescente demanda por aplicações em tempo real tem aumentado a necessidade de fornecimento de QoS na Internet. A arquitetura de Serviços Diferenciados (DiffServ) é uma proposta apresentada pelo IETF para suprir a qualidade de serviço necessária. Resultados de pesquisas, mostram que os componentes da arquitetura DiffServ não distribuem de forma justa os recursos da rede. Este trabalho tem como objetivo propor um mecanismo de marcação de tráfego capaz de melhorar a justiça no compartilhamento da largura de faixa excedente entre agregados de tráfego. O algoritmo de marcação proposto é comparado com os marcadores trTCM, tswTCM e ItswTCM em relação a justiça em diferentes cenários de simulação. Os resultados mostram que o algoritmo proposto apresenta desempenho superior em uma rede com carga de utilização variando entre 20% e 60%.
Recent demand for real time applications has given rise to a need for Quality of Service (QoS) in the Internet. Differentiated Services (DiffServ) is one of such efforts currently pursued by IETF. Previous researchers found unfairness in DiffServ networks. The objective of this work is to propose a new marker which achieves proportional fair sharing of excess bandwidth among aggregates. The proposed algorithm is compared with the following markers trTCM, tswTCM e ItswTCM. Results show that the proposed marker performs better than the other three schemes for network provision level between 20% and 60%.
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Anjali, Tricha. "DiffServ/MPLS Network Design and Management." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5191.
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The MultiProtocol Label Switching (MPLS) framework is used in many networks to provide efficient load balancing which distributes the traffic for efficient Quality of Service (QoS) provisioning in the network. If the MPLS framework is combined with Differentiated Services (DiffServ) architecture, together they can provide aggregate-based service differentiation and QoS. The combined use of DiffServ and MPLS in a network is called DiffServ-aware Traffic Engineering (DS-TE). Such DiffServ-based MPLS networks demand development of efficient methods for QoS provisioning. In this thesis, an automated manager for management of these DiffServ-based MPLS networks is proposed. This manager, called Traffic Engineering Automated Manager (TEAM), is a centralized authority for adaptively managing a DiffServ/MPLS domain and it is responsible for dynamic bandwidth and route management. TEAM is designed to provide a novel and unique architecture capable of managing large scale MPLS/DiffServ domains without any human interference. TEAM constantly monitors the network state and reconfigures the network for efficient handling of network events. Under the umbrella of TEAM, new schemes for Label Switched Path (LSP) setup/teardown, traffic routing, and network measurement are proposed and evaluated through simulations. Also, extensions to include Generalized MPLS (GMPLS) networks and inter-domain management are proposed.
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Li, Na. "Providing quality of service within Diffserv /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004319.
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GARNIER, EDUARDO PASTOR. "ADMISSION CONTROL TECHNIQUES IN A DIFFSERV ENVIRONMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5161@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORAs disciplinas de Controle de Admissão constituem um recurso importante para a obtenção de Qualidade de Serviço em redes de comunicação. Nesse trabalho, é feito um estudo a respeito da aplicação do Controle de Admissão à Internet. Utilizando- se o software ns-2, é avaliado o desempenho de alguns desses mecanismos em cenários distintos e sob diversas condições de tráfego.
Admission control disciplines are un important resource in the search for Quality of Service on communications networks. In this work, we studt the Admission control applications on the Internet. Using the ns-2 networks simulation software, we evaluate the performance of some of these mechanisms on distinct scenarios, and under several circunstances and traffic conditions.
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El, Hachimi Mohamed. "Gestion des communications multicast dans l'architecture diffserv." Besançon, 2004. http://www.theses.fr/2004BESA2064.
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L'augmentation des applications orientées qualité de service et des communications de groupe dans Internet a accéléré le besoin d'un support réseau efficace et prévisible. L'architecture à services différenciés (DiffServ) est une architecture de qualité de service simple et résistant au facteur d'échelle, dans laquelle l'agrégation des flots et la prioritisation des trafics sont les deux principes de base. Cette architecture aura des avantages considérables sur les applications qui exigent des garanties strictes de la qualité de service pour les modes de transfert unicast et multicast. A l'inverse du mode de transfert unicast, l'utilisation des applications multicast dans DiffServ n'est pas une tache simple. Dans ce contexte, nous avons étudié trois problèmes relatifs à l'utilisation du mode de transfert multicast dans DiffServ : le premier problème est celui de la gestion de ressources, le deuxième concerne la résistance au facteur d'échelle multicast et le troisième est lié au support des membres ayant des contraintes hétérogènes de qualité de service dans un même groupe multicast. Suite à l'étude des solutions existantes, nous avons proposé deux solutions pour résoudre le premier problème, l'une centralisée et l'autre distribuée. De même, nous avons présenté une nouvelle technique d'agrégation d'arbres multicast basée sur l'utilisation des nombres premiers et sur l'architecture MPLS pour résoudre les deux autres problèmes. Les résultats obtenus montrent d'une part que le contrôle d'admission est nécessaire pour les applications multicast dans DiffServ et d'autre part que la technique d'agrégation introduite permet d'utiliser un nombre d'états multicast minimal et constant. Par conséquent, le caractère à base d'état du mode de transfert multicast peut être conservé tout en réduisant la complexité des routeurs DiffServThe phenomenal growth of qos-aware applications and per group communications in the internet has accelerated the need for an efficient and scalable network support. The differentiated Services (DiffServ) architecture is simple and scalable quality of service architecture, in which the aggregation of flows and the prioritization of traffics are the two fundamental principles. This architecture will have considerable advantages on unicast and multicast applications having qos requirements. Inversely of unicast transfer mode, the use of multicast applications in DiffServ architecture is not a trivial task. In this context, we addressed three problems: the first one is the problem of resources management, the second is the multicast scalability in DiffServ and the third one concern the support of members having heterogeneous constraints in the same multicast group in DiffServ. Following the study of the existing solutions, this document defines two solutions, centralized and distributed to solve the problem of resource management and proposes a new technique of multicast trees aggregation based on the use of the prime numbers and on MPLS architecture in order to solve the second and the third problem. The obtained results show on one hand that the admission control is necessary for multicast application in DiffServ and on the other hand that the aggregation technique introduced here makes possible the use of a minimum number of multicast state. Consequently, the stateful character of multicast can be preserved while maintaining so simple the DiffServ routers
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Zeman, Otto. "Implementace simulačního modelu zjednodušené databáze DiffServ-MIB." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217563.
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The aim of this work is to propose feasible solution for the simulation of the SNMP (Simple Network Management Protocol) protocol in the OPNET Modeler simulation environment. This work describes in detail individual procedures, which were chosen for this simulation . The work also contains an introduction to the OPNET Modeler simulation environment, the SNMP protocol, the DiffServ model and the DiffServ-MIB database. The main part of this work describes the algorithms programmed to model the functions of the SNMP protocol. Source codes of the algorithms programmed are included as well. The work deals especially with the functions for obtaining values from different levels of a multilevel model attributes, packet creation functions with dynamically changing length of user-data field, for the implementation process of a simplified DiffServ MIB database and with the functions for statistic creation.
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Charalambides, Marinos. "Policy analysis for DiffServ quality of service management." Thesis, University of Surrey, 2009. http://epubs.surrey.ac.uk/2184/.
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Melo, Edison Tadeu Lopes. "Qualidade de serviço em redes IP com DiffServ." Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/80268.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós -Graduação em Computação.Made available in DSpace on 2012-10-18T12:14:03Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T20:45:14Z : No. of bitstreams: 1 181885.pdf: 4358125 bytes, checksum: 334f18a7e45a5a71bb7369373b860ea5 (MD5)
Esse trabalho apresenta uma avaliação sobre a implementação de Qualidade de Serviço (QoS) em redes IP através de medições. Foram testados os padrões DiffServ em diferentes plataformas. A avaliação constituiu-se de duas fases: Na primeira fase, realizou-se uma análise global sobre o ambiente DiffServ e verificou-se a capacidade de isolamento de tráfego e garantia de largura de banda por classe de serviços. Ainda nessa etapa realizou-se monitoração nos nós DiffServ para verificar o comportamento dos mecanismos de classificação e descarte de pacotes. Na segunda fase, a medição de QoS foi empregada para estudar o impacto do tráfego melhor esforço, TCP e UDP, com diferentes tamanhos de pacotes, sobre o desempenho da classe de serviços de tráfego expresso (EF).
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Zhang, Gang. "A sender-initiated resource reservation protocol over Diffserv networks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ55942.pdf.
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Rahim-Amoud, Rana. "Gestion autonome et décentralisée des réseaux MPLS-DiffServ TE." Troyes, 2008. http://www.theses.fr/2008TROY0001.
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La taille des réseaux est de plus en plus importante et leur configuration et leur pilotage sont devenus complexes. De ce fait, la communauté réseau devient consciente de la nécessité de permettre aux réseaux de se configurer et de se piloter de manière autonome. Cette nécessité nous a conduit à proposer une architecture adaptative basée sur les Systèmes Multi- Agents (SMA) dans le but d'assurer une gestion autonome et décentralisée du réseau MPLS-DiffServ TE. MPLS-DiffServ TE permet de fournir une différenciation de service tout en optimisant l'utilisation des ressources du réseau mais dont la gestion est devenue très complexe. Nous avons alors défini les caractéristiques que nous pensons nécessaires pour créer un réseau autonome et avons montré qu'elles sont toutes fournies par les SMA. Nous avons également proposé une stratégie de gestion de LSP, basée sur une approche fondée sur le trafic et dépendant des conditions du réseau. Le but de cette stratégie est de diminuer le nombre de LSP et le nombre d'opérations de signalisation dans le réseau MPLS-DiffServ TE. Pour définir cette stratégie, nous avons étudié le choix de l'approche appropriée pour concevoir un réseau MPLS, les facteurs qui influencent les décisions du SMA, les cas d'échanges entre les différents agents ainsi que le traitement à effectuer à la réception de chaque type de requête. Dans notre proposition, nous avons distingué deux cas de figure, le premier associe un pourcentage fixe de toute la capacité du lien physique à chaque classe de service de DiffServ, tandis que le deuxième utilise des pourcentages dynamiques gérés par le SMA. Les tests réalisés ont montré l'efficacité de notre stratégie qui a permis de réduire le nombre de LSP et d'opérations de signalisation ainsi que le taux de blocage dans le réseauThe size of the networks is increasingly important and their configuration and their piloting is becoming complex. So the network community is, more and more, conscious of the need for allowing the networks to be self-configured and self-controlled in an autonomous way. This need led us to propose an adaptive architecture based on a Multi-Agent System (MAS) to ensure an autonomous and decentralized management of MPLS DiffServ-TE network. MPLS DiffServ-TE combines the advantages of DiffServ and MPLS-TE by allowing a differentiation of services and traffic forwarding on the basis of the required resources. However, the management of such a network is not a simple function and could not be done manually. So, we defined the characteristics which we think necessary to create an autonomous network and we showed that all these characteristics are provided by the MAS. We also proposed an LSP management strategy, based on a traffic-driven approach and dependant on the traffic load. The goal of this strategy is to reduce the number of LSPs and the number of signaling operations in the network. To define this strategy, we studied the choice of the suitable approach to design an MPLS network, the factors which influence the MAS decisions, the cases of exchanges between the various agents as well as the treatments to be realized at the reception of each type of request. In our proposal, we distinguished two different cases, the first one allocates a fixed percentage of all the physical link capacity for each class of service of DiffServ, while the second one allocates a dynamic percentage managed by the MAS. The tests carried out showed the effectiveness of our strategy which reduces the number of LSPs and the number of signaling operations as well as the blocking rate in the network
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Okumus, Ibrahim Taner Chapin Stephen J. Hwang Junseo. "Interdomain traffic engineering on a bandwidth broker-supported diffserv Internet." Related Electronic Resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.
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Al-Wasity, A. J. L. "Virtualized dynamic resource allocation algorithm for the internet DiffServ domains." Thesis, University of Salford, 2017. http://usir.salford.ac.uk/43695/.
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The Differentiated Services (DiffServ) architecture has been proposed for providing different levels of service to the Internet Protocol (IP) traffic. Current discussions in the DiffServ networks are focused on managing resources dynamically according to the traffic conditions of the DiffServ router (Per Hop Behaviour). Software Defined Networks (SDN) and Network Function Virtualisation (NFV) technologies have recently emerged in the research agenda to support researchers in managing network domains and to achieve better use of domain resources. This thesis introduces a new scheduling algorithm called “Dynamic Resource Allocation Management - Network Function Virtualization (DRAM-NFV)” to allocate the service classes resources in the proportional delay DiffServ domains. DRAM-NFV algorithm manages the resources among service classes within the edge routers of the DiffServ domains dynamically according to their traffic conditions and manages these resources between the DiffServ domains in the event of congestion based on their traffic conditions at the egress routers of the upstream domain and ingress routers of the downstream domain. The NFV executes the DRAM-NFV algorithm on a virtualized - Network as a Service (NaaS) - cloud infrastructure to manage the SDN controllers for the edge routers of the DiffServ domains through monitoring the traffic conditions in the service classes at the edge routers and reallocating the out-link resources of the edge routers among service classes. A number of test scenarios were conducted in this research in order to test the performance of the DRAM-NFV algorithm. The performance of DRAM-NFV algorithm is compared with the performance of the DWFQ algorithm by comparing the average End to End Delay for service classes traffic and links utilization. The DWFQ algorithm cannot manage resources between DiffServ domains but can manage the resources locally and dynamically for each DiffServ domain separately. The network simulator NS3 has been used to implement these test scenarios and to test the performance of the DRAM-NFV algorithm. The results show that with the DRAM-NFV algorithm, better balance for DiffServ domains resources can be achieved through monitoring the bandwidth hungry service class at the downstream domain and managing its resources at the upstream domains. As a consequence of this, the utilizations of some service classes traffic are improved and the average End to End Delay for overall traffic are also reduced. An example of the improvement that was achieved by managing resources between (upstream and downstream) DiffServ domains dynamically, in test scenario 3- Case Study 2, the average utilization for the highest priority class (SC1) for whole period of simulation at the destination end is increased by 0.175% and the average End to End Delay for overall traffic is also reduced by 800 msec. As a result of reducing the average End to End Delay for overall traffic and improving the utilizations of service classes traffic, the QoS of applications traffic can be improved during the congestion periods in DiffServ domains.
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Vieira, Sérgio Alexandre Braz. "Realização de uma arquitectura diffServ com configuração transparente de QOS." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/1985.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Electrotécnica e de ComputadoresO foco desta dissertação é o estudo de métodos para a construção e configuração de redes com garantia de qualidade de serviço (QoS – “Quality of Service”) baseados na abordagem de serviços diferenciados (DiffServ). Pretende-se que a configuração da rede seja feita de forma transparente para o utilizador, aproveitando os pacotes de sinalização SIP (“Session Initiation Protocol”) utilizados em várias aplicações multimédia. A dissertação inclui também um enquadramento teórico, no qual se analisam o uso da Internet para serviços de voz (VoIP –“Voice over Internet Protocol”) e a estrutura do núcleo do sistema universal de telecomunicações móveis (UMTS – “Universal Mobile Telecommunications System”) para serviços multimédia (IMS –“Internet Protocol Multimedia Subsystem”). Ainda no âmbito da dissertação, foi elaborado um protótipo utilizando máquinas Linux que consiste numa rede DiffServ com dois tipos de nós: os encaminhadores de fronteira (ER – “Edge Routers”), que efectuam a negociação com os clientes (utilizando SIP); e os encaminhadores nucleares (CR – “Core Routers”), que distribuem os pacotes de acordo com a classe de serviço. A configuração dos CRs é feita dinamicamente em função da carga na rede, utilizando o protocolo COPS (“Common Open Policy Service”). A arquitectura realizada é compatível com os serviços VoIP e com o núcleo do UMTS para o serviço IMS.
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Athuraliya, Sanjeewa Aruna. "TCP Behavior in Quality of Service Networks." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1230.
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Best effort networks fail to deliver the level of service emerging Internet applications demand. As a result many networks are being transformed to Quality of Service (QoS) networks, of which most are Differentiated Services (DiffServ) networks. While the deployment of such networks has been feasible, it is extremely difficult to overhaul the transport layer protocols such as Transmission Control Protocol (TCP) running on hundreds of millions of end nodes around the world. TCP, which has been designed to run on a best effort network, perform poorly in a DiffServ network. It fails to deliver the performance guarantees expected of DiffServ. In this thesis we investigate two aspects of TCP performance in a DiffServ network unaccounted for in previous studies. We develop a deterministic model of TCP that intrinsically captures flow aggregation, a key component of DiffServ. The other important aspect of TCP considered in this thesis is its' transient behavior. Using our deterministic model we derive a classical control system model of TCP applicable in a DiffServ network. Performance issues of TCP can potentially inhibit the adoption of DiffServ. A DiffServ network commonly use token buckets, that are placed at the edge of the network, to mark packets according to their conformance to Service Level Agreements (SLA). We propose two token bucket variants designed to mitigate TCP issues present in a DiffServ network. Our first proposal incorporates a packet queue alongside the token bucket. The other proposal introduces a feedback controller around the token bucket. We validate both analytically and experimentally the performance of the proposed token buckets. By confining our changes to the token bucket we avoid any changes at end-nodes. The proposed token buckets can also be incrementally deployed. Most part of the Internet still remains as a best effort network. However, most nodes run various QoS functions locally. We look at one such important QoS function, i.e. the ability to survive against flows that are non-responsive to congestion, the equivalent of a Denial of Service (DoS) attack. We analyze existing techniques and propose improvements.
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Lee, Myounghwan. "Quality of service with DiffServ architecture in hybrid mesh/relay networks." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34694.
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The objective of this research is to develop an optimized quality of service (QoS) assurance algorithm with the differentiated services (DiffServ) architecture, and a differentiated polling algorithm with efficient bandwidth allocation for QoS assurance in the hybrid multi-hop mesh/relay networks. These wide area networks (WANs), which will employ a connection-based MAC protocol, along with QoS-enabled wireless local area networks (WLANs) that use a contention-based MAC protocol, need to provide an end-to-end QoS guarantee for data communications, particularly QoS-sensitive multimedia communications.
Due to the high cost of construction and maintenance of infrastructure in wireless networks, engineers and researchers have focused their investigations on wireless mesh/relay networks with lower cost and high scalability. For current wireless multi-hop networks, an end-to-end QoS guarantee is an important functionality to add, because the demand for real-time multimedia communications has recently been increasing. For real-time multimedia communication in heterogeneous networks, hybrid multi-hop mesh/relay networks using a connection-based MAC protocol, along with QoS-enabled WLANs that use a contention-based MAC protocol can be an effective multi-hop network model , as opposed to multi-hop networks with a contention-based MAC protocol without a QoS mechanism. To provide integrated QoS support for different QoS mechanisms, the design of the cross-layer DiffServ architecture that can be applied in wireless multi-hop mesh/relay networks with WLANs is desirable.
For parameterized QoS that requires a specific set of QoS parameters in hybrid multi-hop networks, an optimized QoS assurance algorithm with the DiffServ architecture is proposed here that supports end-to-end QoS through a QoS enhanced WAN for multimedia communications.
For a QoS assurance algorithm that requires a minimum per-hop delay, the proper bandwidth to allow the per-hop delay constraint needs to be allocated. Therefore, a polling algorithm with a differentiated strategy at multi-hop routers is proposed here. The proposed polling algorithm at a router differentially computes and distributes the polling rates for routers according to the ratio of multimedia traffic to overall traffic, the number of traffic connections, and the type of polling service.
By simulating the architecture and the algorithms proposed in this thesis and by analyzing traffic with the differentiated QoS requirement, it is shown here that the architecture and the algorithms produce an excellent end-to-end QoS guarantee.
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Barlow, David A. "Router-based traffic engineering in MPLS/DiffServ/HMIP radio access networks." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/15362.
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Macura, Miroslav. "Správa a konfigurace zjednodušené databáze QoS MIB." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218294.
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The main aim of this work was to study the issue of the SNMP protocol and MIB database in order to focus on management and configuration of MIB database using the SNMP protocol. The Master's thesis in detail describes especially creating a communications model of the Manager - Agent type in an OPNET Modeler. In this modeling tool we created exchange of information from the side of the Manager to the side of the Agent via SNMP packets. The Master's thesis is mainly focused on the creation of the SNMP packet according to defined rules, then on reading of information from the MIB database on the side of the Agent and saves this information to the Manager’s MIB database. Exchange of informations is realized via the messages of type GetRequest, GetNext and GetResponse. These models are programmed in language C/C++ and then implemented into the environment of OPNET Modeler.
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Konečný, Zbyněk. "Mapování QoS požadavků na síťové prostředí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218914.
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The issue of converged networks is to ensure the sufficient quality of services along the entire length of the communication transmission. This issue is closely connected to the real-time services, such as VoIP (Voice over Internet Protocol) and videoconferencing. These services require strict adherence to quality parameters, otherwise their function is not guaranteed. This problem particulary resolves subsystem IMS (IP Multimedia Subsystem), which concluded on the basis of user profiles can provide the required quality of service. Therefore the theoretical part deals with the description of the structure of the system and protocols designed to signal the network. Various mechanisms to support quality of services in access and backbone networks are also described. The following section explains the principle of provision of quality requirements of end-user networks. In the practical part is this theoretical knowledge used for designing and configuration of the network consisting of various technologies. The resulting model is then simulated in Opnet Modeler program, which is used for designing and testing of packet networks. Each simulation shows the effect of mapping quality requirements in the different access network on technologies, which are supported in the backbone. The outcome of this work is detailed network analysis and comparison of mechanisms for implementing quality of service. The conclusion summarises all simulation outcomes.
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Silva, Marco Antônio da. "Um SLA para VoIP e seu mapeamento em uma rede DiffServ/MPLS." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/101582.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.Made available in DSpace on 2013-07-15T22:43:32Z (GMT). No. of bitstreams: 1 224770.pdf: 1421169 bytes, checksum: 448611125d813a00481fca9819471e3c (MD5)
Muitas aplicações necessitam garantias de desempenho que as redes IP por si só não fornecem, como garantia de banda e controle de atraso. Algumas ferramentas são utilizadas dentro da rede IP para fornecer a qualidade necessária a estas aplicações, como a arquitetura de Serviços Diferenciados (DiffServ) e a tecnologia MPLS (Multiprotocol Label Switching). Uma das aplicações que exigem certos níveis de qualidade da rede é a voz sobre IP (VoIP). Para permitir a garantia da qualidade dos serviços que o provedor deve fornecer ao seu cliente, são definidos contratos de Acordo do Nível de Serviço (SLA), onde estão descritas as especificações do nível de qualidade a ser fornecido. Este trabalho propõe um SLA para VoIP que permite ao cliente definir quais níveis de qualidade de voz percebida ele necessita, e a provedora mapear estes níveis em parâmetros de desempenho de rede que ela deve garantir. Também são investigados os aspectos de configuração de uma rede DiffServ/MPLS para atendimento do nível de qualidade de serviço. Foram realizados testes num ambiente real, com geração e medição de trafego para avaliar o comportamento da rede, de acordo com a escolha da qualidade de serviço definida dentro da proposta de SLA.
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SANTOS, Ana Paula Silva dos. "O impacto de controladores de banda em domínios DiffServ e roteamento dinâmico." Universidade Federal de Pernambuco, 2002. https://repositorio.ufpe.br/handle/123456789/2559.
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Previous issue date: 202Qualidade de Serviço (QoS) para redes TCP/IP é um conceito que promete promover a utilização de aplicações que necessitam de garantia e confiabilidade, na maior rede de computadores do mundo, a Internet. Dentre as arquiteturas disponíveis para se implementar QoS, uma baseada em priorização de pacotes ou serviços, denominada Serviços Diferenciados (Differentiated Service - DiffServ), define mecanismos e componentes para oferecer mais eficiência na utilização dos recursos da rede. O controlador de banda (Bandwidth Broker - BB) é o componente da arquitetura DiffServ que controla e gerencia os recursos disponíveis na rede, como largura de banda e as políticas de serviços entre domínios vizinhos. O perfil bilateral de negociação de serviços do controlador de banda implica na necessidade de manter um caminho ou rota preestabelecida para cada conexão negociada. Em domínios que utilizam roteamento dinâmico tal proposta é insatisfatória. Esta dissertação propõe um modelo de implementação que possibilita a utilização do controlador de banda em Domínios DiffServ com Roteamento Dinâmico. Neste trabalho, são previstos problemas de renegociação e realocação de recursos dentro de um ou mais domínios, avaliando, com simulações, o desempenho desta proposta
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GAUCHARD, David. "Simulation hybride des réseaux IP-DiffServ-MPLS multi-services sur environnement d'exécution distribuée." Phd thesis, Université Paul Sabatier - Toulouse III, 2003. http://tel.archives-ouvertes.fr/tel-00011034.
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La technologique utilisée dans les réseaux de télécommunication à commutation de paquets est en développement permanent. La tendance actuelle est orientée vers la mutualisation des services voix et données, de leurs infrastructures et des techniques associées (réseaux IP/MPLS, QoS dans Internet). Les méthodes classiques utilisées pour l'évaluation de performances des ces réseaux sont la modélisation analytique et la simulation événementielle. La simulation événementielle requiert des temps de calcul prohibitifs, tandis que les modèles issus des méthodes analytiques manquent parfois de précision. Le travail présenté dans cette thèse définit un cadre de modélisation appelé Simulation Hybride Distribuée qui combine de manière rigoureuse la théorie différentielle du trafic et la simulation événementielle. Dans une première technique, les ressources du réseau sont partitionnées en domaines dont certains sont simulés par événements, et les autres sont modélisés par des équations intégrées numériquement. La seconde technique proposée permet la circulation de trafics simulés par événements sur les ressources du réseau modélisées par des équations. La simulation hybride permet ainsi de prolonger la modélisation analytique au-delà de ses limites théoriques. Elle permet également de concevoir des modèles d'évaluation de performances très généraux et de développer des logiciels plus performants en temps de calculs. Un prototype de simulateur hybride a été conçu. Il permet de modéliser précisément des routeurs Internet Diffserv et MPLS, le protocole TCP ainsi que diverses sources de trafic multimédia (Audio, Vidéo). Pour réduire les temps de calcul, le simulateur peut être parallélisé. En ce sens, un nouveau noyau de communication de l'environnement de parallélisme LANDA a été conçu. Il offre une bibliothèque à la norme MPI et permet d'utiliser simultanément et efficacement (latence, bande passante) plusieurs media de communication haut-débit ainsi que la mémoire commune S MP.
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Gauchard, David. "Simulation hybride des réseaux IP-DiffServ-MPLS multi-services sur environnement d'exécution distribuée." Toulouse 3, 2003. http://www.theses.fr/2003TOU30192.
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Mentz, Joshua. "An investigation into buffer management mechanisms for the Diffserv assured forwarding traffic class." Master's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/5162.
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Includes bibliographical references.One of the service classes offered by Diffserv is the Assured Forwarding (AF) class. Because of scalability concerns, IETF specifications recommend that microflow and aggregate-unaware active buffer management mechanisms such as RIO (Random early detecLion with ln/Out-ofprofile) be used in the core of Diffserv networks implementing AF. Such mechanisms have, however, been shown to provide poor performance with regard to fairness, stability and network controL Furthermore, recent advances in router technology now allow routers to implement more advanced scheduling and buffer management mechanisms on high-speed ports. This thesis evaluates the performance improvements that may be realized when implementing the Diffserv AF core using a hierarchical microflow and aggregate aware buffer management mechanism instead of RIO. The author motivates, proposes and specifies such a mechanism. The mechanism. referred to as H-MAQ or Hierarchical multi drop-precedence queue state Microflow-Aware Quelling, is evaluated on a testbed that compares the performance of a RIO network core with an H-MAQ network core.
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Aziz, Md Tariq, and Mohammad Saiful Islam. "Performance Evaluation of Real–Time Applications over DiffServ/MPLS in IPv4/IPv6 Networks." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5067.
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Over the last years, we have witnessed a rapid deployment of real-time applications on the Internet as well as many research works about Quality of Service (QoS) in particularly IPv4 (Internet Protocol version 4). The inevitable exhaustion of the remaining IPv4 address pool has become progressively evident. As the evolution of Internet Protocol (IP) continues, the deployment of IPv6 QoS is underway. Today, there is limited experience in the deployment of QoS for IPv6 traffic in MPLS backbone networks in conjunction with DiffServ (Differentiated Services) support. DiffServ itself does not have the ability to control the traffic which has been taken for end-to-end path while a number of links of the path are congested. In contrast, MPLS Traffic Engineering (TE) is accomplished to control the traffic and can set up end-to-end routing path before data has been forwarded. From the evolution of IPv4 QoS solutions, we know that the integration of DiffServ and MPLS TE satisfies the guaranteed QoS requirement for real-time applications. This thesis presents a QoS performance study of real-time applications such as voice and video conferencing over DiffServ with or without MPLS TE in IPv4/IPv6 networks using Optimized Network Engineering Tool (OPNET). This thesis also studies the interaction of Expedited Forwarding (EF), Assured Forwarding (AF) traffic aggregation, link congestion, as well as the effect of various performance metrics such as packet end-to-end delay, packet delay variation, queuing delay, throughput and packet loss. The effectiveness of DiffServ and MPLS TE integration in IPv4/IPv6 network is illustrated and analyzed. The thesis shows that IPv6 experiences more delay and loss performance than their IPv4 counterparts.Author (1): Md. Tariq Aziz Address: C/O: Murshed Gularm, Nykarleby Gatan 134, 16474 Kista, Stockholm, Sweden Author (2): Mohammad Saiful Islam Address: Minnervavägen 22B, 371 43 Karlskrona, Sweden
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Doll, Mark. "Management qualitätsbasierter Gruppenkommunikation im Internet." [S.l. : s.n.], 2007. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000009310.
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de, Oliveira Jaudelice C. "New techniques for end-to-end quality of service provisioning in DiffServ/MPLS networks." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/14790.
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Vassiliou, Vasos. "An integration framework and a signaling protocol for MPLS/DiffServ/HMIP radio access networks." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13732.
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Samaniego, Guillen Alex Marcelo. "MPLS-DS : uma plataforma para validação de politicas no contexto das redes MPLS/DiffServ." [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259584.
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Orientador : Mauricio Ferreira MagalhãesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Mestrado
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Vicente, Luiz Henrique. "Estabelecimento de sessões SIP com garantias de Qos e sua aplicação em domínios DiffServ." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94629.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Ciência da Computação, Florianópolis, 2010Made available in DSpace on 2012-10-25T13:47:22Z (GMT). No. of bitstreams: 1 285683.pdf: 1414501 bytes, checksum: 58c677419bf5274aae91be27eb44c9fc (MD5)
A maior parte das soluções de gerenciamento de Qualidade de Serviço (QoS) realizam o tratamento implícito do tráfego de rede sem intervenção dos usuários realizando a chamada. Já existem alguns trabalhos que propõem modificações no protocolo de sinalização SIP (Session Initiation Protocol) para permitir a invocação explícita de QoS durante a negociação da qualidade da sessão. Mas estas propostas adotam uma lista predefinida de parâmetros de QoS e até muitas vezes dependentes de tecnologias. Esta dissertação propõe um mecanismo para negociação dinâmica de QoS em sessões SIP com flexibilidade de especificação de QoS. A presente proposta oferece a flexibilização nos parâmetros para a especificação de QoS com base em uma abordagem semântica. Além disso, a solução proposta adota o protocolo Diameter para autenticação, autorização e contabilidade das sessões SIP, sendo aplicada a um domínio de serviços diferenciados (DiffServ). Os resultados obtidos ao final dos experimentos mostram que, apesar de certo atraso no estabelecimento da sessão SIP, o serviço oferecido ao usuário não fica comprometido, comprovando o funcionamento da proposta.
Most management solutions for Quality of Service (QoS) make the implicit treatment of network traffic without intervention of the user making the call. There are already some studies that propose changes in the SIP protocol (Session Initiation Protocol) to allow explicit QoS negotiation during the session. However, these proposals adopt predefined lists of QoS parameters and frequently dependent on technology. This dissertation proposes a mechanism for dynamic negotiation of QoS in SIP sessions with flexibility in terms of QoS specification. This proposal provides flexibility for specifying QoS parameters based on a semantic approach. Moreover, the proposed solution adopts the Diameter protocol for authentication, authorization and accounting of SIP sessions, and it is applied to a field of differentiated services (DiffServ). The experiment results show that, despite some delay during of the session establishment, the service offered to the user is not compromised, demonstrating the operation of the proposal.
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Fang, Yechang. "Realization of Differentiated Quality of Service for Wideband Code Division Multiple Access Core Network." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/244.
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The development of 3G (the 3rd generation telecommunication) value-added services brings higher requirements of Quality of Service (QoS). Wideband Code Division Multiple Access (WCDMA) is one of three 3G standards, and enhancement of QoS for WCDMA Core Network (CN) becomes more and more important for users and carriers. The dissertation focuses on enhancement of QoS for WCDMA CN. The purpose is to realize the DiffServ (Differentiated Services) model of QoS for WCDMA CN. Based on the parallelism characteristic of Network Processors (NPs), the NP programming model is classified as Pool of Threads (POTs) and Hyper Task Chaining (HTC). In this study, an integrated programming model that combines both of the two models was designed. This model has highly efficient and flexible features, and also solves the problems of sharing conflicts and packet ordering. We used this model as the programming model to realize DiffServ QoS for WCDMA CN. The realization mechanism of the DiffServ model mainly consists of buffer management, packet scheduling and packet classification algorithms based on NPs. First, we proposed an adaptive buffer management algorithm called Packet Adaptive Fair Dropping (PAFD), which takes into consideration of both fairness and throughput, and has smooth service curves. Then, an improved packet scheduling algorithm called Priority-based Weighted Fair Queuing (PWFQ) was introduced to ensure the fairness of packet scheduling and reduce queue time of data packets. At the same time, the delay and jitter are also maintained in a small range. Thirdly, a multi-dimensional packet classification algorithm called Classification Based on Network Processors (CBNPs) was designed. It effectively reduces the memory access and storage space, and provides less time and space complexity. Lastly, an integrated hardware and software system of the DiffServ model of QoS for WCDMA CN was proposed. It was implemented on the NP IXP2400. According to the corresponding experiment results, the proposed system significantly enhanced QoS for WCDMA CN. It extensively improves consistent response time, display distortion and sound image synchronization, and thus increases network efficiency and saves network resource.
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Niang, Ibrahima. "Contribution à l'étude de la qualité de service : application aux environnements DiffServ et aux réseaux sans fil." Paris 5, 2002. http://www.theses.fr/2002PA05S016.
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Cette thèse s'intéresse à l'amélioration des schémas de qualité de service dans les réseaux "backbone" DiffServ et les réseaux d'accès sans fil 802. 11. Une aide au dimensionnement est proposée pour configurer correctement un domaine DiffServ. Un mécanisme de marquage qui prend en compte la spécificité des flux multimédia lors de la traversée de plusieurs domaines est proposé. Cet algorithme est ensuite utilisé dans une architecture de contrôle de qualité de service dont le but est de permettre des mesures intra et inter-domaines. .The present thesis focusses on quality of service schemes within the backbone network and in the 802. 11 wireless access networks. We improve the dimensioning and configuration methods for the DiffServ network. We also propose a marking algorithm for multimedia flows when they cross several domains. We implement this algorithm in a QoS control architecture whose goal is to provide the network operator with the means of measuring QoS intra-domain parameters in the network. .
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Moseng, Tor Kjetil. "A QoS Architecture for Mobile Ad Hoc Networks." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-5761.
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A Mobile Ad Hoc Network (MANET) is a shared wireless network without any infrastructure, consisting of mobile nodes connected by wireless links. The nodes are free to move and organize themselves arbitrarily. The nodes in the network are therefore depending on each other in order to communicate over multiple hops. Due to the physical characteristics of wireless networks, the channel is time-varying, which makes it hard to both predict and sustain a bit rate level. The nodes’ mobility causes topology changes, and further load and capacity variations. Traditional usage areas are battlefield and disaster areas, while new areas like extended network coverage and gaming are emerging. Quality of Service (QoS) is needed in every network in order to differentiate traffic with different performance requirements, e.g. voice and e-mail applications. Providing QoS in wireless environments with varying conditions is complex, and hard guarantees can not be given. Consequently, the aim is to give differentiated treatment to traffic with different performance requirements. In addition, we can not study the MANET without considering fixed networks. Communication with fixed networks is important, for example by accessing the Internet. In this thesis the Differentiated Services (DiffServ) architecture is applied and adapted to MANETs. Using the same QoS architecture will ease the transition between the wireless and wired domain. But the special characteristics of wireless networks require modifications to the original DiffServ architecture. In investigations there was found restrictions on the number of classes to use, and this number was dependent on the type of traffic in the network. A QoS architecture based on the DiffServ framework is proposed, with an admission control based on the concept of shadow classes, and Explicit Congestion Notification (ECN) to avoid congestion. New flows are tested in a shadow class before getting admission to the network and its designated class. The shadow class has the same scheduling properties as the designated class, but is differentiated by a higher drop probability in the buffers. Both the admission control and ECN are thus build on the same principle by controlling the load from probabilistic functions in the buffers, and are studied to find their individual and combined effects. In wireless environments the probability of a packet loss increases with the number of hops, which gives services an unpredictable performance for users. A predictable service, independent of number of hops, is provided by scheduling based on the path information; the packets are differentiated based on the number of hops made or left to make, increasing the predictability at the cost of performance.
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Purificação, Christiane Silva da. "MPLS como suporte à engenharia de tráfego em ambiente com diferenciação de serviço." Universidade Federal de Pernambuco, 2002. https://repositorio.ufpe.br/handle/123456789/2565.
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Previous issue date: 2002A crescente demanda e o explosivo crescimento da Internet está impondo novos desafios para a garantia de serviços em termos de performance, confiabilidade e Qualidade de Serviço (QoS). Muitas aplicações de missão crítica que dependem das tecnologias de rede não podem funcionar sem garantias expressas de entrega. Entretanto, as redes de dados atuais não oferecem nenhuma garantia de que as exigências feitas a nível de serviço possam ser garantidas sem algum tipo de degradação a qualquer hora, do dia ou da noite, a despeito de outros usuários da rede. Para atender essas exigências, a infra-estrutura da rede precisa ser melhorada com novas tecnologias que ofereçam aos operadores de rede ferramentas para controlar o comportamento da mesma. Juntas, as capacidades oferecidas pela Engenharia de Tráfego, pelo MPLS (Multiprotocol Label Switching) e pelo DiffServ possibilitam o controle e o balanceamento de carga na rede necessários à entrega de serviço de acordo com contratos personalizados. Este trabalho apresenta o MPLS associado à Engenharia de Tráfego como solução para o problema de alocação ineficiente dos recursos em uma rede e o conseqüente congestionamento provocado por tal problema. O esquema de encaminhamento de pacotes do MPLS é empregado como estratégia para minimizar o congestionamento ou alternativamente maximizar a utilização dos recursos, através da alocação eficiente dos mesmos, garantindo, num ambiente com diferenciação de serviço, uma melhor Qualidade de Serviço em termos de redução na perda de pacotes, no atraso e na variação de atraso, e no aumento da vazão agregada
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Heng, Tu Yueh, and 杜岳衡. "Resource Allocation in DiffServ-capable MPLS Network." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/18082916803576521016.
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碩士國立交通大學
資訊管理所
88
Switching technology provides an ideal solution to the performance of layer 2 network, while the main goals of multi-layer switching technology are to solve performance problems and to combine more routing mechanisms. This research uses quality of service as main evaluation standard. On the premise that supporting differentiated service to achieve QoS, we use multi-protocol label switching (MPLS) as the core technology. Using connection-oriented label switching path to classify and route different types of traffic flows, and labels each path with different priority labels. By the capability of explicit routing, hoping to control the bandwidth utilization in a MPLS domain more effectively. Moreover, to provide satisfying service to some special QoS requirement. This thesis will perform some simulations on the connection priorities of a single path and multi path routing behavior. In order to prove that under the condition of insufficient bandwidth, rerouting lower priority connection will increase bandwidth utilization and the QoS of traffic flows can also have certain guarantee.
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Chen, Chao-Wei, and 陳昭維. "DEPLOYING RESOURCE RESERVATION PROTOCOL IN DIFFSERV NETWORKS." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/63727687762766315073.
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碩士大同大學
通訊工程研究所
89
Differentiated Services (DiffServ) is proposed by IETF as a low-cost architecture to provide Quality of Service in IP networks (IP-QoS). The DiffServ architecture consists of two key components: traffic conditioning at the edges and Per Hop Behavior (PHB) at the core. Traffic conditioners are realized with various building blocks such as classifier, meter, marker, policer etc. This thesis is focused on the study of DiffServ. The results of the study help us to understand the design choices for some of the DiffServ architecture building blocks in a DiffServ-enabled router. DiffServ has good scalability in the backbone but it needs a signaling protocol to get guaranteed service. Resource reSerVation Protocol (RSVP), a signaling protocol for end-to-end guaranteed service and extensively supported by industry, is a good choice to be deployed with DiffServ to verify the delay performance. Our simulation results show this way of deployment not only solves the problem of QoS scalable because of DiffServ but also gets the QoS guarantee.
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Liu, Hao-Fan, and 劉浩帆. "A DIFFSERV MUTLICASTING IN MOBILE IPV6 NETWORKS." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/29651628367988558827.
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碩士銘傳大學
資訊工程學系碩士班
97
In this paper we propose an approach to establish a DiffServ-aware multicast tree in a mobile IPv6 network. First, we use a modified Dijkstra algorithm to compute the maximum available bandwidth map (MABM) to all nodes. Then, a DiffServ-aware multicast tree can be constructed by referring to the MBM. Each core router in the established multicast tree must maintain a new quality of service (QoS) table in order to forward the received multicast packets to the mobile node (MN). Finally, when a MN moves to a new network, a tunnel must be established in order to satisfy the MN’s QoS. The simulation results have shown that the proposed approach has better performance, especially in the case where the traffic is high.
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HSII, NICHOLAS, and 許佳仁. "Architecture Design of WDRR Scheduler with DiffServ." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/18631991769901553758.
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碩士國立中正大學
電機工程研究所
91
Recently, multimedia service increase rapidly in the high-speed Internet network, and those service all attach importance to QoS(quality of service). So an appropriate mechanism in the switch or router is needed to enhance QoS. This thesis aims to propose Weighted Deficit Round Robin (WDRR) Scheduler, which is one of the solutions to supply QoS with DiffServ in the switch or router. WDRR can divide the input packets into EF/AF1/AF2/AF3/AF4/BE class according packet’s TOS octet. Each class has reserved queue. User can decide quantum size of each class to meet the requirement of QoS. On the other hand, WDRR have very low complexity to implement in high-speed network environment by hardware. In this paper, We develop WDRR Scheduling policy,design Hardware Architecture of WDRR SCHEDULER,and use Verilog HDL to implement it, the input traffic packet of WDRR SCHEDULER include all 6 kind of packet, We observe the result in the output The simulation result proves that WDRR SCHEDULER is effective and practicable.
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Cheng, Hsin-Ho, and 鄭新禾. "Design for Auctioning Qualitative Service in DiffServ Network." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/33856810814235196266.
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碩士國立臺灣大學
電機工程學研究所
88
Abstract Offering Quality of Service (QoS) in IP network is an important issue for next generation Internet. IETF proposes the Differentiated Service (DiffServ) Architecture as a suitable, practical, and scalable solution to IP QoS provisioning. In addition to direct control such as traffic policing, indirect control by pricing has been identified as essential for QoS control. The design of pricing schemes for DiffServ network is an open research topic. Comparing with per-flow QoS guaranteed service, the per service class QoS control granularity of DiffServ causes rougher network transport service guarantee. Thus, the purchasing behavior of users toward such classified and QoS-roughly-controlled services becomes even more nontrivial. This is the greatest challenge when designing pricing schemes for DiffServ networks. This thesis is focused on pricing the qualitative service, where qualitative service offers relative QoS to users. Using qualitative service, the network performance of some users is guaranteed to be relatively better than that of other users’. Qualitative service is user sensitive, and easy to implement in current network infrastructure. When pricing qualitative network resource, one of the most troublesome issues is that users’ utility information is unknown. To solve the uncertainty of user utility information, the pricing scheme design proposed in this thesis adopts auction mechanism. Users reveal utility information naturally through their bidding action in the market, and the utility reflects on the market price of the network resource, driving the market price to an efficient and stable point. In the auction-based market mechanism, users bid in the market to buy the peak rate they can deliver using qualitative service queue. The resource allocation follows a proportional rate allocation scheme. The market price is floating, driven by the competition of resource among users. A user determines the bid following his utility toward network resource. He observes the information of the market such as total market value and total provisioned resource. Then he makes bids according to the observed data to maximize his own benefit. There are two trading modes for market operation: asynchronous trading mode and synchronous trading mode. Asynchronous trading mode deals with user bids variation whenever the variation takes place. It gives fast response to users. Synchronous trading mode deals with users bids periodically in batch job style. Its operation produces less signaling burden in the network. Game theoretic analysis is performed on the designed market mechanism. We prove that under a very general assumption of user utility characteristics, the designed market converges to a unique Nash Equilibrium Point (NEP), at which every user in the market doesn’t wish to change his bidding action unilaterally. Moreover, the market is also proved to have two reasonable properties versus the quantity of auctionable resource. They are “the uniformity of user purchase versus resource provision” and “the law of diminishing returns”. Results of experimental simulation support our theory derivation. Reference implementation architecture is realized in a small network to validate our market design. The implementation framework consists of three parts: a pricing server, agents, and a DiffServ QoS router. The pricing server is built on Windows NT 4.0 TM with Internet Information Server TM installed. It takes care of the market operation and dynamically generates web pages that reveal market information to users. An agent is built on a web browser. It offers users an interface to bid and observe the information of the market. The router is built on Linux with DiffServ patch and JSDK installed. The router uses Java Servlets to communicate with the pricing server. An IP traffic control framework is planted in the OS kernel to manage DiffServ QoS control. Working examples shows that the reference implementation achieves our market mechanism design.
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Lin, Yi-Neng, and 林義能. "Scalability and Bottlenecks of DiffServ over Network Processors." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/45848931569046403946.
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碩士國立交通大學
資訊科學系
89
Network processors are emerging as a programmable alternative to the traditional ASIC-based solutions in scaling up the user-plane processing of network services. They serve as co-processors to offload user-plane traffic from the original general-purpose microprocessor. In this work, we illustrate the process and investigate performance issues in prototyping a DiffServ edge router with IXP1200, which has one control-plane StrongARM core processor and six user-plane microengines, and stores classification and scheduling rules at SRAM and packets at SDRAM. The external benchmark shows that the system can support an aggregated throughput of 141Mbps of eight input ports, and 500 flows, which is extensible provided enough SRAM space, at one input port while conforming the PHB of each flow. Through internal benchmarks, we found that performance bottlenecks may shift from one place to another given different network services and implementations. For simple forwarding services, SDRAM is a nature bottleneck. However, it could shift to SRAM or microengines if involving heavy table access or computation, respectively. We also identify the design pitfall of the hardware called the “MAC buffer problem”.
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Zhu, Li. "Network level performance of differentiated services (diffserv) networks." Thesis, 2006. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2006-047.
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Khan, Azhar Shabbir, and Bilal Afzal. "MPLS VPNs with DiffServ : A QoS Performance Study." Thesis, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14521.
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MPLS (Multiprotocol Label Switching) VPNs (Virtual private network) are new alternatives to private WANs (Wide area network). They are gaining popularity in industry day by day. Enterprise customers are moving to service providers that offer MPLS VPNs. The main reason for this shifting is the capability of MPLS VPN to provide built in security features and any-to-any connectivity. QoS (Quality of service) is the most important element for enterprise networks. Enterprise network have video, audio and data traffic over a single network infrastructure.In this thesis we will investigate QoS parameters (e.g. delay, jitter and packet loss) over MPLS VPNs environment. It will help the service providers and enterprise network customers to maintain QoS for voice, video and data traffic over MPLS VPNs environment.To achieve consistent end-to-end QoS, the service provider and the enterprise customer must work closely together and share the same policies to implement because service provider participates in customer routing in MPLS VPN environment. We will use the DiffServ (Differentiated services) QoS model over MPLS VPN network. We will use a six class model for service provider network and enterprise customer network to achieve end-to- end service quality.In the last part we will make tests of end-to-end traffic delay, jitter and packet loss. We will compare the results of delay, jitter and packet loss with and without the DiffServ QoS model in an MPLS VPNs environment. It will be clear in the results that without using DiffServ QoS model delay, jitter and packet loss are increasing as the traffic increases on the network. With a DiffServ enabled network, the increase of traffic over network will not affect delay, jitter and packet loss and provide constant level of service quality.
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Lu, Chun-Ta, and 呂俊達. "IP Multicast with DiffServ in IPv6 Mobility Environment." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/zw5q6h.
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碩士銘傳大學
資訊工程學系碩士班
94
With the evolution of the network technology, we can access the Internet by the wireless network even when moving. Based on the infrastructure, some applications would provide multicast services, the way of forwarding only to partial receivers, to their users in a group. However, multicast transmission may probably be influenced and cause the degradation of transmission quality when a mobile host (MH) moved from one network to another in a mobile IP network. The purpose of our research is to overcome this problem and keeps the quality of service (QoS) of a MH unchanged after moving. The proposed approach consists of three parts. First, the maximum bandwidth map (MBM) is established based on the link state database maintained by OSPF. The purpose of MBM is just a reference for a MH to join the multicast tree after the MH moves to another network. Second, a quality of service manager (QM) is used and in charge of establishing the multicast tree, processing the join path selection and maintaining the updated multicast tree after a MH submits a join message to a multicast tree. Third, a queuing scheme, called bonus time queue (BTQ) is used to increase the extra time for transmitting multicast packets in case of the insufficient of bandwidth in the network. The simulation results have shown that the proposed approach has better performance than other algorithms and improved the QoS requirements of a MH.
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Sun, Jiunn-Jer, and 孫俊哲. "Comparison of Interoperation Schemes for DiffServ and IntServ." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/99578799987066318930.
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Al, Wehaibi Abdullah Ahmed. "QoS multicast for DiffServ on MPLS and IP platforms." Thesis, 2003. http://spectrum.library.concordia.ca/2377/1/NQ90372.pdf.
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Multicasting has become increasingly important with the emergence of Internet-based applications such Internet protocol (IP) telephony, audio/video conferencing, distributed databases and software upgrading. IP Multicasting is an efficient way to distribute information from a single source to multiple destinations at different locations. One of the challenges the Internet is facing today is to keep the packet forwarding performance up with the skyrocketing demand for bandwidth. On the other hand, the MultiProtocol Label Switching (MPLS), which is an Internet Engineering Task Force (IETF) framework, combines the flexibility of layer 3 routing and layer 2 switching, which enhances network performance in terms of scalability, computational complexity, latency and control message overhead. Besides, MPLS offers a vehicle for enhanced network services such as Quality of Services (QoS)/Class of Service (CoS), Traffic Engineering and Virtual Private Networks (VPNs). In this thesis, we present a new Fair Share Policy (FSP), which is a traffic policing mechanism that utilizes Differentiated Services (DiffServ) to solve the problems of QoS and congestion control. We compare the QoS performance of IP and MPLS multicasting, given their particular constraints. In order to achieve the required QoS, different techniques of reliable multicasting are adapted, such as Forward Error Correction (FEC), Automatic Repeat Request (ARQ) or Hybrid FEC/ARQ with multicast or unicast repairs mechanisms so as to mitigate the effect of errors as well as packet loss. This reliable multicast is for both IP and MPLS platforms with Diffserv. Analytical and simulation models are suggested and employed. The results provide insights into the comparisons between IP multicast in MPLS networks using FSP and plain IP multicasting using the same policy when DiffServ is adopted and when reliable multicast is considered. This comparison will be based on the following QoS measures: total packet delay, delay jitter and residual packet loss probability. Analysis and simulation tools are used to evaluate our fair share policy (FSP) for different homogeneous (when all routers are identical in their capabilities) and heterogeneous (when routers have different capabilities) network scenarios.
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鄭永宏. "The Traffic Conditioner improving Bandwidth Allocation for DiffServ Networks." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/46197762706582523592.
Full textAbstract:
碩士國立交通大學
電信工程系
90
The Differentiated Services (DiffServ; DS) architecture is proposed for providing the practical QoS guarantee. In DiffServ, the Internet traffic is separated to several classes according to the contracts signed between customers and service providers. Each class is offered with different QoS guarantee. The traffic conditioner, an element located in the edge router, is used to measure the arrival flow of aggregate traffic against the traffic profile and takes corresponding actions such as marking packets based on the measuring result. Each packet will be marked as either in- or out-of-profile when it exits the traffic conditioner. The corresponding actions will be taken in the later DS nodes according to the condition of network and the mark of packet. The leaky bucket mechanism is a deterministic flow control network element that is usually used in traditional traffic conditioner. However, there are several drawbacks in traditional traffic conditioner. First, the unfair marking appears and certain micro-flows would not achieve the deserved QoS requirement. Second, if a connection through more DS domains, it would be more probable to be demoted and dropped. In this thesis, we propose the TC_PFG (Traffic Conditioner with Promotion and Fairness Guarantee) and eTC_PFG (enhanced TC_PFG) to amend the inappropriate markings in traditional traffic conditioners. The new schemes are based on TRTCM (Two Rate Three Color Marker) scheme. They allocate appropriate bandwidth to micro-flows to reduce the unfair distribution among micro-flows and improve the utilization by allowing promotion of packets when there is available bandwidth. Simulation results show that both TC_PFG and eTC_PFG outperform the TRTCM and eTC_PFG performs better than TC_PFG.
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Mahadik, Vinay Ashok. "Detection of denial of QoS attacks on DiffServ networks." 2002. http://www.lib.ncsu.edu/theses/available/etd-08132002-143359/unrestricted/etd.pdf.
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Liu, Yu-Sunn, and 劉有順. "QoS Guarantee in Interconnected DiffServ Based on MPLS Network." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/12045760015908157325.
Full textAbstract:
碩士元智大學
資訊工程學系
90
Because of the diversity of Internet information transit such as Voice, Data and Video, the traditional Integrated Service Model can no longer satisfy the users’ requirements for the different qualities of services. A Differentiated Services Model was designed to meet the different transit stratagem for the services of different Classes and different charging standards for ISP business. Along with the rapid increase in transit speed, the Differentiated Services Model seems to lag behind, especially in the interconnected switches for different Internet services. To adjust the channel bandwidth of the (frequency) temporarily or regularly becomes a pressing task needed to be conquered. An important internet technique MPLS (Multi Protocol Label Switch), guaranteeing the qualities of the transited materials in internet, can insure high qualities of an internet terminal to terminal transit, with no need to service the flowing paths of datagram information in the current information. Besides, it can improve the expansion of Internet and offer a simple service class to the class-marked ISP. With its characteristic in marking short, simple, fixed lengths, the MPLS can provide a compact way of information transit. The purpose of the thesis is to create a new Bandwidth Control System for the Differentiated Services Model and MPLS. The System can adjust itself automatically according to the temporary adjustment, regular adjustment and the block out percentage of the bandwidth; hence, it can effectively increase the usage percentage and cut down the block out percentage of the bandwidth. Hopefully the System can offer a connected principle for the Interconnected Service Quality solving the major factors that influence the qualities while using Interconnected. Judging from the effect of the whole, and finding out different service qualities for different Classes, the auto adjustment principle (the System) can offer a completely different style of guaranty for different quality of services. Keywords：MPLS (Multi Protocol Label Switch)，Interconnected，DSCP，PH
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Jheng, Bo-Wun, and 鄭博文. "Impact of Out-of-Order Delivery in DiffServ Networks." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/24771481310702754874.
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碩士國立中山大學
電機工程學系研究所
94
Packet reordering is generally considered to have negative impact on network performance. In this thesis, the packet reordering is used to assist TCP to recover faster in RED-enabled packet switched networks. The RED queue management prevents networks from congestion by dropping packets with a probability earlier than the time when congestion would actually occur. After a RED router drops a packet, packer reordering is introduced during TCP’s recovery process. A new, simple buffer mechanism, called RED with Recovery Queue or R2Q, is proposed to create this type of packet reordering on behalf of TCP with the objective of accelerating TCP’s recovery and thus improving the overall network performance. In R2Q, the original RED queue is segmented into two sub-queues. The first sub-queue remains the function of the original RED while the second picks up the packets discarded by the first. Then, scheduling of the second-chance transmission of the packets in the secondary sub-queue is the key in achieving our objective. In this thesis, we considered two scheduling schemes: priority and weighted round robin. To evaluate the performance of R2Q with these two scheduling schemes, we implemented and evaluated them in the J-Sim network simulation environment. The well-known dumbbell network topology was adopted and we varied different parameters, such as round-trip time, bottleneck bandwidth, buffer size, WRR weight and so on, in order to understand how R2Q performs under different network configurations. We found that R2Q is more effective in the networks of sufficient buffer and larger product of RTT and bandwidth. With WRR, we may achieve as much as 2% improvement over the original RED. The improvement may be more in networks of even higher speed.
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Chiang, Guey-jyu, and 江桂菊. "The Influence of Router’s DiffServ on VoIP’s Voice Quality." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/42604178524898318736.
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碩士輔仁大學
資訊工程學系
94
Most VoIP service uses Best Effort approach to transmit voice packets in current IP Internet. They provide services without QoS support. Lacking of QoS support has significant impact on transmission of Real-time packets. VoIP packets may be lost, or delayed during the transmission. User may get discontinued voice or even disconnect. Thus, Internet has to provide a good QoS mechanism for VoIP, and the most popular technology available is the Differentiated Service (DiffServ). DiffServ suggests classifying and remarking the packets on Edge Routers and process and transmitting packets on Core Router. Due to the classification of quality level; DiffServ enhances the scalability of Internet. Also by the separation of Edge and Core routers, it enhances the process efficiency of routers in Internet. In this thesis, proper router’s parameter settings for VoIP application are investigated. Following the suggestions, VoIP applications can get good voice quality (such as PSQM value), reduce the packet loss rate, eliminate delay and jitter. Proper setting on parameters can benefit router vendors, VoIP developers, and DiffServ administrators.