121 research outputs found

    Theories and Models for Internet Quality of Service

    Get PDF
    We survey recent advances in theories and models for Internet Quality of Service (QoS). We start with the theory of network calculus, which lays the foundation for support of deterministic performance guarantees in networks, and illustrate its applications to integrated services, differentiated services, and streaming media playback delays. We also present mechanisms and architecture for scalable support of guaranteed services in the Internet, based on the concept of a stateless core. Methods for scalable control operations are also briefly discussed. We then turn our attention to statistical performance guarantees, and describe several new probabilistic results that can be used for a statistical dimensioning of differentiated services. Lastly, we review recent proposals and results in supporting performance guarantees in a best effort context. These include models for elastic throughput guarantees based on TCP performance modeling, techniques for some quality of service differentiation without access control, and methods that allow an application to control the performance it receives, in the absence of network support

    Advances in Internet Quality of Service

    Get PDF
    We describe recent advances in theories and architecture that support performance guarantees needed for quality of service networks. We start with deterministic computations and give applications to integrated services, differentiated services, and playback delays. We review the methods used for obtaining a scalable integrated services support, based on the concept of a stateless core. New probabilistic results that can be used for a statistical dimensioning of differentiated services are explained; some are based on classical queuing theory, while others capitalize on the deterministic results. Then we discuss performance guarantees in a best effort context; we review: methods to provide some quality of service in a pure best effort environment; methods to provide some quality of service differentiation without access control, and methods that allow an application to control the performance it receives, in the absence of network support

    Minimizing queueing delays in computer networks

    Get PDF
    Ph.DDOCTOR OF PHILOSOPH

    Proportional delay differentiation employing the CBQ service discipline

    Full text link

    ABE: providing a low-delay service within best effort

    Get PDF
    Alternative best effort (ABE) is a novel service for IP networks, which relies on the idea of providing low delay at the expense of possibly less throughput. The objective is to retain the simplicity of the original Internet single-class best-effort service while providing low delay to interactive adaptive applications

    Network level performance of differentiated services (diffserv) networks

    Get PDF
    The Differentiated Services (DiffServ) architecture is a promising means of providing Quality of Service (QoS) in Internet. In DiffServ networks, three service classes, or Per-hop Behaviors (PHBs), have been defined: Expedited Forwarding (EF), Assured Forwarding (AF) and Best Effort (BE). In this dissertation, the performance of DiffServ networks at the network level, such as end-to-end QoS, network stability, and fairness of bandwidth allocation over the entire network have been extensively investigated. It has been shown in literature that the end-to-end delay of EF traffic can go to infinity even in an over-provisioned network. In this dissertation, a simple scalable aggregate scheduling scheme, called Youngest Serve First (YSF) algorithm is proposed. YSF is not only able to guarantee finite end-to-end delay, but also to keep a low scheduling complexity. With respect to the Best Effort traffic, Random Exponential Marking (REM), an existing AQM scheme is studied under a new continuous time model, and its local stable condition is presented. Next, a novel virtual queue and rate based AQM scheme (VQR) is proposed, and its local stability condition has been presented. Then, a new AQM framework, Edge-based AQM (EAQM) is proposed. EAQM is easier to implement, and it achieves similar or better performance than traditional AQM schemes. With respect to the Assured Forwarding, a network-assist packet marking (NPM) scheme has been proposed. It has been demonstrated that NPM can fairly distribute bandwidth among AF aggregates based on their Committed Information Rates (CIRs) in both single and multiple bottleneck link networks

    Quality of service at the computer networks based on internet

    Get PDF
    А framework for the emerging computer networks quality of Internet service is presented. Two important components of the framework are considered: integrated service and differentiated service. They are described and problems related to their implementation are discussed. Two broadly classified algorithms are investigated: scheduling and queue management algorithms. The model of the average time delay for the type packet is presented.Запропоновано структуру забезпечення якості надання послуг Internet. Розглянуто два важливі компоненти цієї структури: інтегроване та диференційоване обслуговування, їх реалізацію та пов’язані з нею проблеми. Досліджено два алгоритма: планування і управління чергою. Запропоновано модель даних, яка базується на теорії масового обслуговування.Предложена структура обеспечения качества предоставления услуг Internet. Рассмотрены два важных компонента этой структуры: интегрированное и дифференцированное обслуживание, их реализация и связанные с ней проблемы. Исследованы два алгоритма: планирования и управления очередью. Предложена модель данных, базирующаяся на теории массового обслуживания

    Quality of service at the computer networks based on internet

    Get PDF
    А framework for the emerging computer networks quality of Internet service is presented. Two important components of the framework are considered: integrated service and differentiated service. They are described and problems related to their implementation are discussed. Two broadly classified algorithms are investigated: scheduling and queue management algorithms. The model of the average time delay for the type packet is presented.Запропоновано структуру забезпечення якості надання послуг Internet. Розглянуто два важливі компоненти цієї структури: інтегроване та диференційоване обслуговування, їх реалізацію та пов’язані з нею проблеми. Досліджено два алгоритма: планування і управління чергою. Запропоновано модель даних, яка базується на теорії масового обслуговування.Предложена структура обеспечения качества предоставления услуг Internet. Рассмотрены два важных компонента этой структуры: интегрированное и дифференцированное обслуживание, их реализация и связанные с ней проблемы. Исследованы два алгоритма: планирования и управления очередью. Предложена модель данных, базирующаяся на теории массового обслуживания
    corecore