Measuring available bandwidth and capacity represents an essential requirement for a multitude of network applications spanning from traffic engineering and admission control to network security. Measurement techniques frequently presume to know capacity a priori, but this constitutes a weak premise in a number of modern scenarios due to conditions such as abstractions in infrastructure virtualization, dynamic demands in resource sharing and fluctuations in interference, all of which can affect capacity in short time spans. Despite consistent efforts, currently employed techniques struggle to balance accuracy, intrusion and freshness, depending on either substantial intrusion, onerous processing or unfeasible deployment. Recent developments on data plane programmability have breathed new life into this undertaking, allowing observation points to be more efficiently distributed and programmable packet methods to be executed in-situ. This paper proposes CAPEST, a passive capacity and available bandwidth measurement method for the data plane, employing packet dispersion and autocorrelation. The method is evaluated regarding its parametrization sensitivity, its intrusion and freshness in comparison to state-of-the-art techniques and its performance in the real-world application of video routing. CAPEST was found to incur substantially (80%) less intrusion and achieve 10% better accuracy, all the while providing an order of magnitude improvement in freshness.

中文翻译：

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CAPEST：将网络容量和可用带宽估计卸载到可编程数据平面

测量可用带宽和容量代表了从流量工程和准入控制到网络安全的众多网络应用程序的基本要求。测量技术经常假设先验地知道容量，但由于基础设施虚拟化中的抽象、资源共享中的动态需求和干扰波动等条件，这在许多现代场景中构成了一个弱前提，所有这些都会在短期内影响容量时间跨度。尽管做出了一致的努力，当前采用的技术仍难以平衡准确性、入侵和新鲜度，这取决于大量入侵、繁重的处理或不可行的部署。数据平面可编程性的最新发展为这项事业注入了新的活力，允许更有效地分布观察点和现场执行可编程的分组方法。本文提出了 CAPEST，一种用于数据平面的无源容量和可用带宽测量方法，它采用数据包分散和自相关。与最先进的技术相比，该方法的参数化敏感性、侵入性和新鲜度及其在视频路由的实际应用中的性能进行了评估。发现 CAPEST 引起的入侵显着减少 (80%)，准确度提高了 10%，同时提供了一个数量级的新鲜度改进。使用数据包分散和自相关。与最先进的技术相比，该方法的参数化敏感性、侵入性和新鲜度及其在视频路由的实际应用中的性能进行了评估。发现 CAPEST 引起的入侵显着减少 (80%)，准确度提高了 10%，同时提供了一个数量级的新鲜度改进。使用数据包分散和自相关。与最先进的技术相比，该方法的参数化敏感性、侵入性和新鲜度及其在视频路由的实际应用中的性能进行了评估。发现 CAPEST 引起的入侵显着减少 (80%)，准确度提高了 10%，同时提供了一个数量级的新鲜度改进。