Network telemetry is to collect information (e.g., hop latency, throughput) from network devices. Network-wide telemetry is critical for operators to understand the quality of network performance and to diagnose on-going failures. The state-of-the-art telemetry approaches are far from ideal as they are unable to fully satisfy diverse requirements of operators, specifically for on-demand, full coverage, and scalable telemetry.

In this paper, we provide a new framework of network telemetry for data center networks, called NetView. NetView can support various telemetry applications and telemetry frequencies on demand, monitoring each device via proactively sending dedicated probes while only one vantage server is required. Technically, NetView divides the probe into a forwarding stack and a telemetry stack, which are respectively responsible for flexible forwarding and network status monitoring, achieving full coverage and visibility. Besides, a series of probe generation algorithms and update algorithms largely reduce probe number, providing high scalability. The evaluation shows that NetView reduces the bandwidth occupancy by more than two orders of magnitude compared with Pingmesh and INT-path, and conducts network-wide telemetry for the data center network with thousands of switches using only one vantage server, without bringing about resources bottleneck.

网络遥测是从网络设备收集信息（例如，跳时延，吞吐量）。全网遥测对于运营商了解网络性能的质量并诊断持续的故障至关重要。最先进的遥测方法远非理想，因为它们无法完全满足运营商的各种要求，特别是按需，全覆盖和可伸缩遥测。

在本文中，我们为数据中心网络提供了一个新的网络遥测框架，称为NetView。NetView可以按需支持各种遥测应用程序和遥测频率，通过主动发送专用探测器来监视每个设备，而只需要一个有利的服务器。从技术上讲，NetView将探针分为转发堆栈和遥测堆栈，它们分别负责灵活的转发和网络状态监视，以实现全面的覆盖范围和可见性。此外，一系列探针生成算法和更新算法大大减少了探针数量，提供了高可扩展性。评估显示，与Pingmesh和INT-path相比，NetView将带宽占用减少了两个数量级以上，并且仅使用一台有利的服务器就对具有数千个交换机的数据中心网络进行了全网遥测，而不会造成资源瓶颈。