ITR: Collaborative Rsearch: Scalable Quality-of-Service Control for the Next Generation Internet

今天的互联网之所以取得巨大成功，要归功于25年前推出的简单的“沙漏”IP网络协议体系结构。近年来，随着网络技术的快速发展和丰富多媒体内容的爆炸性增长，网络社区发现自己正处于一个重要的十字路口：下一代互联网架构应该是什么，以控制网络资源并提供新兴多媒体应用所需的服务质量(Qos)？有多种可能的方法来提供服务质量保证。为下一代互联网选择服务质量解决方案将对互联网本身的发展及其实现的功能产生重大影响。要做出“正确”的选择，需要从根本上了解服务质量控制的可扩展性，以及这些控制对服务质量供应有效性的影响。拟议研究的目标是全面、定量地了解提供可扩展的服务质量保证的各种方法所涉及的基本权衡。为此，我们将开发连贯的理论来系统地解决服务质量控制中的可扩展性问题。研究计划大致分为四个领域：保证流的聚合网络演算：为了彻底了解网络系统在提供Qos性能保证方面的精细时间尺度(例如，分组级别)行为，研究人员将开发聚合网络演算来研究聚合QOS控制机制对数据平面操作的性能和复杂性的影响。这一理论是为保证流开发的，这些流要求网络在其整个生命周期内在每个流或聚合级别提交一定量的资源(例如，带宽和缓冲区)，而不管网络拥塞状态如何。聚合网络演算将提供一个数学框架，以量化聚合服务质量控制对服务质量配置中的基本权衡的影响。它还将为可扩展数据平面的服务质量控制机制的设计提供深入的见解。响应流的端到端服务质量控制：研究人员将开发流体模型来研究聚合服务质量控制机制对响应流的端到端性能的影响。响应流通过调整其传输速率来响应网络拥塞的迹象，例如丢失。这些模型将使我们能够更好地了解响应流的行为，例如结合不同聚合Qos机制的TCP，并为响应流设计端到端的Qos服务。服务质量控制律和控制平面聚合规则。我们将开发用于捕获网络的慢时间尺度、系统范围行为的服务质量控制律，以及用于解决服务质量聚合控制下控制平面操作的性能和复杂性的聚合规则。这些服务质量控制规则和聚合规则将引导我们为可扩展的控制平面操作设计分布式和集中式算法。可扩展的服务质量机制和服务体系结构作为发展这些理论的一个组成部分，研究人员还将设计有效和可扩展的服务质量机制，以及用于量化和评估各种服务质量解决方案的工具和技术。基于这些努力的结果，研究人员将研究如何组合各种Qos解决方案来构建有意义的端到端服务。这项研究将融合正式的建模/分析、实验/实现和评估。我们的研究所获得的理解和见解将导致建立理论、设计原则和指导方针，以构建面向未来互联网的可扩展的Qos控制。反过来，随着下一代互联网的形成，这将使人们能够做出理性和明智的选择。

Today's Internet owes its great success to the simple, "hour-glass" IP network protocol architecture laid out twenty-five years ago. With rapid advances in networking technologies and explosive growth of rich multimedia content in recent years, the networking community finds itself at an important crossroads: what should be the next generation Internet architecture for controlling network resources and provide the quality of service (QoS) needed by emerging multimedia applications? There is a multidimensional spectrum of possible approaches to providing QoS guarantees. The choice of a QoS solution for the next generation Internet will have a substantial impact on both the evolution of the Internet itself, and on what it enables. Making the "right" choices requires the development of a fundamental understanding of the scalability of QoS controls and the impact of these controls on the efficacy of QoS provisioning. The goal of the proposed research is to develop a comprehensive, quantitative understanding of the fundamental trade-offs involved in various approaches toward providing scalable QoS guarantees. To this end, we will develop coherent theories to systematically address the issue of scalability in QoS controls. The research program divides broadly into four areas: Aggregate network calculus for guaranteed flows: To gain a thorough understanding of the fine time-scale(e.g., packet-level) behavior of a network system in providing QoS performance guarantees, the researchers will develop an aggregate network calculus to study the impact of aggregate QoS control mechanisms on the performance and complexity of data plane operations. This theory is developed for guaranteed flows - flows which require the network to commit, either at a per-flow or an aggregate level, a certain amount of resources (e.g., bandwidth and buffer) throughout their life time, regardless of the network congestion status. The aggregate network calculus will provide a mathematical framework to quantify the impact of aggregate QoS controls on the fundamental trade-offs in QoS provisioning. It will also yield insights into the design of scalable data plane QoS control mechanisms. End-to-end QoS controls for responsive flows: The researchers will develop fluid models to study the impact of aggregate QoS control mechanisms on the end-to-end performance of responsive flows. A responsive flow responds to signs of network congestion, such as loss, by adapting its transmission rate. These models will enable us to develop a better understanding of the behavior of responsive flows such asTCP coupled with different aggregate QoS mechanisms and to design end-to-end QoS services for responsive flows. QoS control laws and control plane aggregation rules. We will develop QoS control laws for capturing the slow time-scale, system-wide behavior of a network and aggregation rules that address the perfor-mance and complexity of control plane operations under aggregate QoS controls. These QoS control laws and aggregation rules will lead us to the design of distributed and centralized algorithms for scalable control plane operations. Scalable QoS mechanisms and service architectures As an integral part in developing these theories, the researchers will also design effective and scalable QoS mechanisms, and tools and techniques for quantifying and evaluating the trade-offs of various QoS solutions. Based on the results from these efforts, the researchers will study how various QoS solutions can be combined to construct meaningful end-to-end services. The research will blend formal modeling/analysis, experimentation/implementation, and evaluation. Theunderstanding and insights gained as a result of our research will lead to the establishment of the theory,design principles, and guidelines for building scalable QoS controls for the future Internet. This, in turn,will allow reasoned and informed choices to be made as the next generation Internet takes shape.