Video streaming applications constitute a significant portion of the Internet traffic today, with mobile accounting for more than half of the online video views. The high share of video in the current Internet traffic mix has prompted many studies that examine video streaming through measurements. However, streaming performance depends on many different factors at different layers of the TCP/IP stack. For example, browser selection at the application layer or the choice of protocol in transport layer can have significant impact on the video performance. Furthermore, video performance heavily depends on the underlying network conditions (eg, network and link layers). For mobile networks, the conditions vary significantly, since each operator has a different deployment strategy and configuration. In this paper, we focus on YouTube and carry out a comprehensive study investigating the influence of different factors on streaming performance. Leveraging the Measuring Mobile Broadband Networks in Europe (MONROE) test bed that enables experimentation with 13 different network configurations in four countries, we collect more than 1800 measurement samples in operational mobile networks. With this campaign, our goal is to quantify the impact of parameters from different layers on YouTube's streaming quality of experience (QoE). More specifically, we analyze the role of the browser (eg, Firefox and Chrome), the impact of transport protocol (eg, TCP or QUIC), the influence of network bandwidth, and signal coverage on streaming QoE. Our analysis reveals that all these parameters need to be taken into account jointly for network management practices, in order to ensure a high end‐user experience.

中文翻译：

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剖析移动网络中YouTube视频流的性能

视频流应用程序构成了当今Internet流量的重要部分，其中移动占在线视频观看量的一半以上。在当前的互联网流量组合中，视频所占的比例很高，这促使许多研究通过测量来检查视频流。但是，流传输性能取决于TCP / IP堆栈不同层上的许多不同因素。例如，在应用层选择浏览器或在传输层选择协议可能会对视频性能产生重大影响。此外，视频性能在很大程度上取决于基础网络条件（例如，网络和链路层）。对于移动网络，条件各不相同，因为每个运营商都有不同的部署策略和配置。在本文中，我们专注于YouTube，并进行了一项全面的研究，以调查不同因素对流媒体性能的影响。利用欧洲测量移动宽带网络（MONROE）测试平台，可以在四个国家/地区测试13种不同的网络配置，我们在运营中的移动网络中收集了1800多个测量样本。通过此广告系列，我们的目标是量化不同层的参数对YouTube流式体验质量（QoE）的影响。更具体地说，我们分析了浏览器（例如Firefox和Chrome）的作用，传输协议（例如TCP或QUIC）的影响，网络带宽的影响以及信号质量对流式QoE的影响。我们的分析表明，对于网络管理实践，需要共同考虑所有这些参数，