Abstractions for Network Update
Abstractions for Network Update
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DOI：
10.1145/2377677.2377748
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发表时间：
2012-10-01
影响因子：
2.8
通讯作者：
Walker, David
中科院分区：
文献类型：
--
作者：
Reitblatt, Mark;Foster, Nate;Walker, David
配置更改是网络中不稳定的常见来源，导致中断，性能中断和安全漏洞。即使初始配置和最终配置正确，更新过程本身也经常通过表现出不正确行为的中间配置进行逐步逐步进行。本文介绍了一致的网络更新更新的概念，这些更新可以保证在配置之间过渡时保留明确的行为。我们确定了两个不同的一致性级别，即每包和每流量，并提出了使用Switch API（例如Open Flow）在软件定义的网络中实现它们的一般机制。我们开发了开放流网络的正式模型，并证明一致的更新可保留大量属性。我们描述了我们的原型实现，包括几种优化，以减少执行一致更新所需的开销。我们提出了一个验证工具，该工具利用一致的更新，可以显着降低检查网络控制软件的正确性的复杂性。最后，我们描述了一些简单实验的结果，这些实验证明了这些优化在示例应用程序上的有效性。
Configuration changes are a common source of instability in networks, leading to outages, performance disruptions, and security vulnerabilities. Even when the initial and final configurations are correct, the update process itself often steps through intermediate configurations that exhibit incorrect behaviors. This paper introduces the notion of consistent network updates updates that are guaranteed to preserve well-defined behaviors when transitioning between configurations. We identify two distinct consistency levels, per-packet and per-flow, and we present general mechanisms for implementing them in Software-Defined Networks using switch APIs like Open Flow. We develop a formal model of Open Flow networks, and prove that consistent updates preserve a large class of properties. We describe our prototype implementation, including several optimizations that reduce the overhead required to perform consistent updates. We present a verification tool that leverages consistent updates to significantly reduce the complexity of checking the correctness of network control software. Finally, we describe the results of some simple experiments demonstrating the effectiveness of these optimizations on example applications.