A recent advance in networking is the deployment of path-aware multipath network architectures, where network endpoints are given multiple network paths to send their data on. In this work, we tackle the challenge of selecting paths for latency-sensitive applications. Even today's path-aware networks, which are much smaller than the current Internet, already offer dozens and in several cases over a hundred paths to a given destination, making it impractical to measure all path latencies to find the lowest latency path. Furthermore, for short flows, performing latency measurements may not provide benefits as the flow may finish before completing the measurements. To overcome these issues, we argue that endpoints should be provided with a latency estimate before sending any packets, enabling latency-aware path choice for the first packet sent. As we cannot predict the end-to-end latency due to dynamically changing queuing delays, we measure and disseminate the propagation latency, enabling novel use cases and solving concrete problems in current network protocols. We present the Global Latency Information Dissemination System (GLIDS), which is a step toward global latency transparency through the dissemination of propagation latency information.

翻译：近期网络领域的一项进展是部署了路径感知的多路径网络架构，在该架构中网络端点拥有多条可发送数据的网络路径。本研究致力于解决延迟敏感型应用的路径选择难题。即便当前规模远小于互联网的路径感知网络，已可为特定目的地提供数十条乃至上百条路径，这使得通过测量所有路径延迟来寻找最低延迟路径的做法不切实际。此外，对于短流而言，执行延迟测量可能毫无裨益，因为在测量完成前该流可能已结束传输。为克服这些问题，我们认为应在端点发送数据包前为其提供延迟估计值，从而实现对首个数据包发送的延迟感知路径选择。由于动态变化的排队延迟使我们无法预测端到端延迟，我们转而通过测量并传播传播延迟来支持新型应用场景并解决当前网络协议中的具体问题。本文提出全局延迟信息传播系统（GLIDS），该系统通过传播传播延迟信息，向着实现全局延迟透明度迈出了关键一步。