An Event-driven Programmable Network Architecture for the Next Generation Internet

近年来，使用互联网的应用程序的数量和多样性呈爆炸式增长。 在过去，大多数通过互联网的数据流量是可靠的、有序的、非实时的，并且在一对固定的主机之间。 然而，下一代互联网将需要支持非常多样化的环境（例如，异构有线/无线和移动的网络），应用（例如，多媒体、WWW、telnet）和服务（多播、不同类别的服务质量等）。 由于具有不同要求的应用程序需要对网络的动态做出不同的反应，因此下一代互联网协议必须在处理特定应用程序要求的方式上更加积极主动。 此外，还需要为新兴应用开发和快速部署新服务。在这个项目中，我们提出了一种新的事件驱动可编程网络架构，是可扩展的，强大的，灵活的，可扩展的，简单的程序。 我们的体系结构，使新的网络服务的用户和服务提供商，动态创建虚拟网络，服务质量，服务广告，灵活的网络资源管理和资源仲裁之间的竞争应用程序的实例化。 我们的目标是使网络编程几乎像编程一台独立的计算机一样简单。我们的方法是提供网络的事件驱动视图。 “虚拟网络”由一组服务定义，每个服务都是一个事件、事件处理程序对。 网络提供一组默认的服务。 每个服务提供商可以创建其自己的“虚拟网络上下文”，其是虚拟网络的实例化。 虚拟网络上下文具有分层结构，即，服务提供者可以允许用户或应用在服务提供者的上下文内创建他们自己的虚拟网络上下文。 每个虚拟网络上下文继承其父上下文的服务，但可以自定义这些服务或创建新服务。 可以通过将事件绑定到不同的事件处理程序或通过创建新事件（可以由其他事件处理程序触发）来自定义服务。 一个网络范围的“分布式服务目录”维护一个（部分）可用和公开传播的服务库。 在这个模型中，一个虚拟的网络环境可以很容易地定制零碎的改变只有少数相关的服务给用户。 与此同时，通过混合和匹配公共可用服务的菜单，可以很容易地组合新服务并构建整个虚拟网络。为了使编程服务简单，我们的架构提供了一个简单的编程抽象的分布式网络状态的应用程序，从而降低了开发服务的复杂性。 分布式网络管理器提供用于访问、更新、高速缓存和锁定属于潜在异构网络中的多个节点的本地和非本地网络状态的简单机制。 网络管理器是一个自配置的分布式软件，基于我们过去开发的“脊柱”基础设施，并提供资源管理，资源分配和顶级虚拟网络上下文之间的资源仲裁。 我们相信，我们的组合服务模型和网络管理架构是独一无二的，在当代的研究，并可能被证明是一个合适的架构，为下一代互联网。为了更好地理解真实的环境中架构和服务需求的微妙之处，我们将构建一个由跨越全国的异构有线/无线网络组成的四群集测试床，群集位于尚潘、芝加哥、波士顿和圣何塞。 我们将与摩托罗拉、传威和Maverick半导体合作建立基础设施。 HTIS开发的目标是在移动的计算环境中为单播和多播流提供服务质量。 我们选择这个应用环境是因为它的复杂性和我们以前在传统Internet环境中构建这样的环境的专业知识。 我们相信，在这个项目的最后，我们将能够开发出一个架构，可以有效地解决hte下一代互联网的多样化和复杂的需求。

Recent years have witnessed an explosive growth in the volume and the diversity of applications that use the Internet. IN the past, most of the data traffic traversing the Internet was reliable, sequenced, non real-time, and between a stationary pair of hosts. However, the next generation Internet will need to support very diverse environments (e.g., heterogeneous wireline/wireless and mobile networks), applications (e.g., multimedia, WWW, telnet), and services (multicast, different classes of quality of service, etc.). Because applications with diverse requirements need to react differently to the dynamics of the network, the next generation Internet protocols will, of necessity, have to be more proactive in the way they deal with application-specific requirements. Additionally, new services will need to be developed and rapidly deployed for emerging applications. In this project, we propose a novel event-drive programmable network architecture that is scalable, robust, flexible, extensible, and simple to program. Our architecture enables on-the-fly instantiation of new network services both by users and service providers, dynamic creation of virtual networks, quality of service, service advertisement, flexible network resource management, and resource arbitration among contending applications. Our goal is to make programming the network almost as simple as programming a stand-alone computer. Our approach is to provide an event-drive view of the network. A 'virtual network' is defined by a set of services, each of which is an event, event-handler pair. The network provides a default set of services. Each service provider can create its own 'virtual network context', which is an instantiation of a virtual network. Virtual network contexts have a hierarchical structure, i.e., a service provide may allow users or applications to create their own virtual network contexts within the context of the service provide. Each virtual network context inherits the services of its parent context, but can customize these services or create new ones. Services can be customized either by binding an event to a different event-handler, or by creating new events (which can be triggered by other event-handlers). A network-wide 'distributed services directory' maintains a (partial) library of available and publicly disseminated services. In this model, a virtual network context can be easily customized piecemeal by changing only a few of the services relevant to a user. At the same time, it is easy to compose new services and build entire virtual networks by mixing and matching from a menu of publicly available services. In order to make programming services simple, our architecture provides a simple programming abstraction of the distributed network state to applications, thereby reducing the complexity of developing services. A distributed network manager provides simple mechanisms for accessing, updating, caching, and locking both local and non-local network state belonging to multiple nodes in potentially heterogeneous networks. The network manager is a self-configuring distributed software based on the 'spine' infrastructure that we have developed in the past, and also provides resource management, resource allocation, and resource arbitration among top-level virtual network contexts. We believe that our combined service model and network management architecture is unique in contemporary research, and may prove to be an appropriate architecture for the next generation Internet. In order to better understand the subtleties of the architecture and service requirements in a real environment, we will build a four cluster testbed consisting of heterogeneous wireline/wireless networks spanning the country, with clusters located in Champaign, Chicago, Boston, and San Jose. We will build hte infrastructure in collaboration iwth Motorola, TranSwitch, and Maverick Semiconductor. The goal of htis evnvironment is to provide quality of service for unicast and multicast flows in a mobile computing environment. We choose this application environment because of its comcplexity and our previous expertise in building such environments in the context of hte traditional Internet. We believe that at the ned of this project, we iwll be able to develop an architecture that can effectively address the diverse and complex requirements of hte next generation Internet.