Autonomous Systems (ASes) exchange reachability information between each other using BGP---the de-facto standard inter-AS routing protocol. While IPv4 (IPv6) routes more specific than /24 (/48) are commonly filtered (and hence not propagated), route collectors still observe many of them.

In this work, we take a closer look at those "hyper-specific" prefixes (HSPs). In particular, we analyze their prevalence, use cases, and whether operators use them intentionally or accidentally. While their total number increases over time, most HSPs can only be seen by route collector peers. Nonetheless, some HSPs can be seen constantly throughout an entire year and propagate widely. We find that most HSPs represent (internal) routes to peering infrastructure or are related to address block relocations or blackholing. While hundreds of operators intentionally add HSPs to well-known routing databases, we observe that many HSPs are possibly accidentally leaked routes.

自治系统 (AS) 使用 BGP（事实上的标准 AS 间路由协议）在彼此之间交换可达性信息。虽然比 /24 (/48) 更具体的 IPv4 (IPv6) 路由通常会被过滤（因此不会传播），但路由收集器仍然会观察到其中的许多路由。

在这项工作中，我们仔细研究了那些“超特定”前缀 (HSP)。特别是，我们分析了它们的流行程度、用例，以及运营商是有意还是无意地使用它们。虽然它们的总数随着时间的推移而增加，但大多数 HSP 只能被路由收集器对等方看到。尽管如此，一些 HSP 可以在一整年中不断出现并广泛传播。我们发现大多数 HSP 代表到对等基础设施的（内部）路由，或者与地址块重定位或黑洞有关。虽然数百家运营商有意将 HSP 添加到知名路由数据库中，但我们观察到许多 HSP 可能是意外泄露的路由。