Low Earth Orbit (LEO) satellite networks have attracted considerable attention for their ability to deliver global, low-latency broadband Internet services. In this paper, we present a large-scale measurement study of the Starlink network, the largest LEO satellite constellation to date. We first propose an efficient method for discovering active Starlink user routers, identifying approximately 5.98 million IPv6 addresses across 208 regions in 165 countries. Compared to general-purpose IPv6 target generation algorithms, our router-centric approach achieves near-complete coverage and, to the best of our knowledge, yields the most comprehensive known set of active IPv6 addresses for Starlink user routers. Based on the discovered user routers, we further propose an efficient method for mapping the Starlink backbone network and uncover a topology consisting of 49 Points of Presence (PoPs) interconnected by 98 links. We conduct a detailed statistical analysis of active Starlink user routers and PoPs, and further characterize the IPv6 address assignment strategy adopted by the Starlink network. Finally, we analyze the latency of Starlink user routers, propose a method to distinguish different types of users within the same region using outside-in measurement, and identify the ongoing V2 Mini satellite deployment as a potential driver of the performance improvements. The dataset of the Starlink backbone network is publicly available at https://ki3.org.cn/#/starlink-network.

翻译：低地球轨道（LEO）卫星网络因其能够提供全球性、低延迟的宽带互联网服务而受到广泛关注。本文对迄今为止最大的低地球轨道卫星星座——星链网络——开展了一项大规模测量研究。我们首先提出了一种高效发现活跃星链用户路由器的方法，在165个国家的208个区域中识别出约598万个IPv6地址。与通用的IPv6目标生成算法相比，我们以路由器为中心的方法实现了近乎完整的覆盖，据我们所知，该方法获得了目前已知最全面的星链用户路由器活跃IPv6地址集合。基于所发现的用户路由器，我们进一步提出了一种高效映射星链骨干网络的方法，揭示出由98条链路互连49个入网点（PoP）构成的拓扑结构。我们对活跃的星链用户路由器及入网点进行了详细的统计分析，并进一步刻画了星链网络采用的IPv6地址分配策略。最后，我们分析了星链用户路由器的延迟特性，提出了一种通过外部测量区分同一区域内不同类型用户的方法，并指出正在进行的V2 Mini卫星部署可能是性能提升的潜在驱动因素。星链骨干网络的数据集已公开于https://ki3.org.cn/#/starlink-network。