IMPROVING STARLINK’S LATENCY ｜ 改善星链的延迟

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IMPROVING STARLINK’S LATENCY 改善星链的延迟

Starlink engineering teams have been focused on improving the performance of our network with the goal of delivering a service with stable 20 millisecond (ms) median latency and minimal packet loss.

Starlink工程团队一直致力于提高我们网络的性能，目标是提供稳定的20毫秒（ms）中位延迟的服务，同时最小化数据包丢失。

Over the past month, we have meaningfully reduced median and worst-case latency for users around the world. In the United States alone, we reduced median latency by more than 30%, from 48.5ms to 33ms during hours of peak usage. Worst-case peak hour latency (p99) has dropped by over 60%, from over 150ms to less than 65ms. Outside of the United States, we have also reduced median latency by up to 25% and worst-case latencies by up to 35%.

在过去的一个月里，我们显著降低了全球用户的中位和最坏情况下的延迟。仅在美国，我们在高峰时段将中位延迟从48.5毫秒降低了30%以上，从150毫秒以上降低到不到65毫秒。在美国之外，我们还将中位延迟降低了高达25%，将最坏情况下的延迟降低了35%。

Latency

延迟

Latency refers to the amount of time, usually measured in milliseconds, that it takes for a packet to be sent from your Starlink router to the internet and for the response to be received. This is also known as “round-trip time”, or RTT. Latency is one of the most important factors in your perceived experience when using the internet – web pages load faster, audio and video calls feel closer to real-life, and online gaming feels responsive. As an example, testing has shown that increasing bandwidth beyond around 10 Mbps does not increase web-page load time, but a reduction in latency results in substantially lower load times.

延迟是指从您的星链路由器发送数据包到互联网并接收响应所需的时间，通常以毫秒为单位计量。这也被称为“往返时间”，或RTT。延迟是使用互联网时感知体验中最重要的因素之一 - 网页加载更快，音频和视频通话感觉更接近真实，在线游戏感觉更具响应性。例如，测试表明，将带宽增加到10 Mbps以上并不会增加网页加载时间，但延迟减少会大大降低加载时间。

To measure Starlink’s latency, we collect anonymized measurements from millions of Starlink routers every 15 seconds. These 15 second average latencies are then used to calculate the median and worst-case latency. The median (50th percentile or p50) refers to the point where half of the latency measurements are below that number and the other half are above. The worst-case latency, or 99th percentile, is defined as the place where 99% of measurements are better than the point. While we look at data from all points in time, we specifically focus on the performance during hours of peak usage (6-9 PM local time), when the largest number of people are using Starlink, and the network is under the most load.

为了测量星链的延迟，我们每15秒从数百万个星链路由器中收集匿名测量数据。然后，使用这些15秒的平均延迟来计算中位数和最坏情况下的延迟。中位数（第50百分位数或p50）指的是延迟测量值一半在该数字以下，另一半在该数字以上的点。最坏情况下的延迟，或第99百分位数，被定义为99%的测量结果都优于该点的位置。虽然我们查看所有时间点的数据，但我们特别关注高峰时段（当地时间晚上6点至9点），这时使用星链的人数最多，网络负载最重。

What Drives Latency 是什么造成了延迟

Latency in the Starlink network is driven by several factors. The biggest ones are:

星链网络的延迟受到几个因素的影响。其中最重要的因素是：

• Physical speed-of-light propagation from the user to the satellite and back to the ground. This is in the range of 1.8-3.6ms per leg, and usually under 10ms for the round-trip. Additional latency can be induced if traffic flows over laser links, instead of directly to the ground (as a result of congestion mitigation, lack of satellite to ground paths, or other factors). While laser connectivity is essential for connecting the most remote locations on Earth and for routing around congestion in the network, we are making strides to ensure that latency sensitive traffic can flow over the shortest path possible.

• 用户到卫星再返回地面的物理光速传播。这一传播时间在1.8-3.6毫秒之间，通常往返不超过10毫秒。如果流量通过激光链路而不是直接传输到地面（这是由于拥塞缓解、缺乏卫星到地面路径或其他因素造成的），可能会引入额外的延迟。虽然激光连接对于连接地球上最偏远的地区以及在网络中绕过拥塞至关重要，但我们正在努力确保延迟敏感的流量能够沿着尽可能最短的路径流动。

• Ground latency from the gateway sites to the internet connection point driven by ground network layout. In 2024, we are adding 6 internet connect locations (called Points of Presence, or PoPs) in the US and are optimizing gateway locations and our planning algorithms to ensure that traffic can land as close to its destination point as possible. We will continue to ensure that users are allocated to optimal internet connection locations, so that all users get the lowest latency possible route to the internet.

• 从网关站点到互联网连接点的地面延迟，受地面网络布局的影响。2024年，我们将在美国增加6个互联网连接位置（称为PoPs），并优化网关位置和我们的规划算法，以确保流量尽可能地靠近其目标点着陆。我们将继续确保用户被分配到最佳的互联网连接位置，以便所有用户都能得到通往互联网的最低延迟路径。

• Fronthaul (the radio links between the satellite and user) scheduling latency driven by the network topology and the number of users served by a given beam from a satellite. While this latency is an inherent part of shared wireless systems, there is significant room for optimization, and this has been a major focus in the past several months.

• 前向链路（卫星与用户之间的无线电链路）调度延迟，受网络拓扑和由卫星给定波束服务的用户数量的影响。虽然这种延迟是共享无线系统的固有部分，但存在着重要的优化空间，这已经成为过去几个月的主要焦点。

• Dumb stuff driven by non-physical limitations in our system – unneeded processing delays, unoptimized buffers, or unnecessary packet drops that force retries. Buffers across our network have been right sized to reduce bufferbloat, and queueing algorithms have been improved to increase capacity on our gateway links from the ground to satellites. Our WiFi latency has been improved, with the addition of active queue management, fq_codel, to the Starlink WiFi router. With active queue management enabled, when one person on your WiFi is downloading a big file, and another is playing a game, the game latency will not be affected by the download.

• 非物理限制导致的愚蠢问题 - 不必要的处理延迟、未经优化的缓冲区或不必要的数据包丢弃，迫使重试。我们网络中的缓冲区已经被正确调整大小以减少缓冲区过度膨胀，并且排队算法已经得到改进，以增加从地面到卫星的网关链路的容量。我们的WiFi延迟得到了改善，通过向星链WiFi路由器添加积极的队列管理，fq_codel。启用积极的队列管理后，当您WiFi上的一个人正在下载大文件时，另一个人正在玩游戏，游戏延迟不会受到下载的影响。

Continuing Towards Our 20ms Goal 继续朝着我们的20毫秒目标努力

Over the past several months, monitoring and metrics have also been added across the network to measure latency on every subsystem down to the microsecond. We have rigorously tuned our algorithms to prefer paths with lower latency, no matter how small the difference and to remove any and all sources of unnecessary and non-physical latency.

在过去几个月中，监控和指标也已经在整个网络中添加，以测量每个子系统的延迟，直到微秒级别。我们已经严格调整了我们的算法，以偏好延迟较低的路径，无论差异多么小，并消除了任何不必要和非物理延迟的来源。

This is just a selection of some of the most impactful changes we have made. Since the beginning of the year, teams have deployed and tested 193 different satellite software builds, 75 gateway software builds, 222 Starlink software builds, and 57 WiFi software builds.

这只是我们所做的一些最有影响力的变化的一部分。自年初以来，团队已经部署和测试了193个不同的卫星软件版本、75个网关软件版本、222个星链软件版本和57个WiFi软件版本。

Thank you to our 2.6M+ customers for choosing Starlink. You can expect latency to continue to improve over the coming weeks and months as we prioritize software changes, build additional ground infrastructure, and launch more satellites. In future updates, we’ll communicate other performance statistics and goals of our network as we work to improve your experience.

感谢我们260万多位客户选择星链。随着我们优先考虑软件更改、建设更多的地面基础设施和发射更多的卫星，您可以期待延迟在未来几周和几个月内继续改善。在未来的更新中，我们将与您沟通我们网络的其他性能统计数据和目标，以改善您的体验。

Be sure to check the latest latency statistics for your region at starlink.com/map.

请务必查看starlink.com/map上您所在地区的最新延迟统计数据。