Today's network measurements rely heavily on Internet-wide scanning, employing tools like ZMap that are capable of quickly iterating over the entire IPv4 address space. Unfortunately, IPv6's vast address space poses an existential threat for Internet-wide scans and traditional network measurement techniques. To address this reality, efforts are underway to develop ``hitlists'' of known-active IPv6 addresses to reduce the search space for would-be scanners. As a result, there is an inexorable push for constructing as large and complete a hitlist as possible. This paper asks: what are the potential benefits and harms when IPv6 hitlists grow larger? To answer this question, we obtain the largest IPv6 active-address list to date: 7.9 billion addresses, 898 times larger than the current state-of-the-art hitlist. Although our list is not comprehensive, it is a significant step forward and provides a glimpse into the type of analyses possible with more complete hitlists. We compare our dataset to prior IPv6 hitlists and show both benefits and dangers. The benefits include improved insight into client devices (prior datasets consist primarily of routers), outage detection, IPv6 roll-out, previously unknown aliased networks, and address assignment strategies. The dangers, unfortunately, are severe: we expose widespread instances of addresses that permit user tracking and device geolocation, and a dearth of firewalls in home networks. We discuss ethics and security guidelines to ensure a safe path towards more complete hitlists.

翻译：当今网络测量严重依赖互联网范围扫描，利用ZMap等工具可快速遍历整个IPv4地址空间。然而，IPv6庞大的地址空间对互联网范围扫描和传统网络测量技术构成了根本性挑战。为应对这一现实，学界正在努力构建已知活跃IPv6地址的"活跃地址表"，以缩小潜在扫描器的搜索空间。由此产生了构建尽可能大规模、完整活跃地址表的不可阻挡趋势。本文提出关键问题：当IPv6活跃地址表规模扩大时，可能带来哪些益处与危害？为回答该问题，我们获得了迄今为止最大规模的IPv6活跃地址数据集：79亿个地址，是当前最优活跃地址表的898倍。尽管我们的数据集并非全面覆盖，但已是重大突破，为更完整活跃地址表所能实现的分析类型提供了初步洞察。将数据集与先前IPv6活跃地址表比较后，我们揭示了双重影响。益处包括：提升对客户端设备（此前数据集主要由路由器构成）的洞察能力、实现网络中断检测、追踪IPv6部署进展、发现此前未知的别名网络，以及分析地址分配策略。然而危害同样严峻：我们发现了大量允许用户追踪和设备地理定位的地址实例，以及家庭网络中防火墙部署的严重缺失。为此，我们讨论了构建更完整活跃地址表过程中的伦理准则与安全指南，以确保其发展路径的安全性。