This paper presents NemFi: a trace-driven WiFi emulator. NemFi is a record-and-replay emulator that captures traces representing real WiFi conditions, and later replay these traces to reproduce the same conditions. In this paper, we demonstrate that the state-of-the-art emulator that was developed for cellular links cannot emulate WiFi conditions. We identify the three key differences that must be addressed to enable accurate WiFi record-and-replay: WiFi packet losses, medium-access control, and frame aggregation. We then extend the existing cellular network emulator to support WiFi record-and-replay. We evaluate the performance of NemFi via repeated experimentation across different WiFi conditions and for three different types of applications: speed-test, file download, and video streaming. Our experimental results demonstrate that average application performance over NemFi and real WiFi links is similar (with less than 3 percent difference).

中文翻译：

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神经网络

本文介绍了 NemFi：一种跟踪驱动的 WiFi 仿真器。NemFi 是一个记录和重放模拟器，它捕获代表真实 WiFi 条件的轨迹，然后重放这些轨迹以重现相同的条件。在本文中，我们证明了为蜂窝链路开发的最先进的仿真器无法模拟 WiFi 条件。我们确定了实现准确 WiFi 记录和回放必须解决的三个关键差异：WiFi 数据包丢失、媒体访问控制和帧聚合。然后，我们扩展现有的蜂窝网络仿真器以支持 WiFi 记录和回放。我们通过在不同 WiFi 条件下和三种不同类型的应用程序（速度测试、文件下载和视频流）的重复实验来评估 NemFi 的性能。