Abstractions for network update
Abstractions for network update
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DOI：
10.1145/2342356.2342427
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发表时间：
2012-08
影响因子：
88.1
通讯作者：
Mark Reitblatt;Nate Foster;J. Rexford;Cole Schlesinger;D. Walker
中科院分区：
文献类型：
--
作者：
Mark Reitblatt;Nate Foster;J. Rexford;Cole Schlesinger;D. Walker
配置更改是网络不稳定的常见原因，会导致中断、性能中断和安全漏洞。即使初始配置和最终配置都是正确的，更新过程本身也经常会遍历表现出不正确行为的中间配置。本文介绍了一致性网络更新的概念-在配置之间转换时保证保持良好定义的行为的更新。我们确定了两个不同的一致性级别，每个数据包和每个流，我们提出了一般的机制，实现它们在软件定义的网络使用交换机API，如OpenFlow。我们开发了OpenFlow网络的正式模型，并证明了一致的更新保持了一大类属性。我们描述了我们的原型实现，包括几个优化，减少执行一致的更新所需的开销。我们提出了一个验证工具，利用一致的更新，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的实验结果，证明了这些优化的有效性的示例应用程序。
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 mbetween 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 OpenFlow. We develop a formal model of OpenFlow 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.