subnet.im

AS19043OneBeacon Insurance Group LTD

United StatesRegistryARIN

As of 24th October 2026, AS19043 (OneBeacon Insurance Group LTD), a network registered in the United States with ARIN, originates 4 IPv4 prefixes covering 9.2k addresses. By IPv4 address space that makes it the 10,994th-largest of the 79,664 networks we see originating IPv4, and the 3,311th-largest of 18,488 in the United States. It is seen behind 3 upstream networks, most often AS18540 (Recovery Point Systems Inc.) and AS6461 (Zayo Bandwidth). None of its announcements have a valid RPKI ROA. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

4

IPv6 prefixes

0

IPv4 addresses

9.2k

IPv6 /64s

0

Upstream graph

The networks AS19043 is seen behind, one and two hops out, drawn from real AS paths.

AS19043Toward the internet core
Upstream graph for AS19043: 7 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS19043OneBeacon Insuran…This networkAS701Verizon BusinessAS6461Zayo BandwidthAS18540Recovery Point Sy…AS1299Arelion (fka. Tel…AS2914NTT America, Inc.AS3356Lumen (Level 3)AS32590Valve Corporation

Networks observed one and two hops upstream of AS19043 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

6

adjacent networks

Upstreams
350%
Peers
350%
Downstreams
00%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS19043
NetworkCountryRelationshipPathsVantage pts
AS18540Recovery Point Systems Inc.USPeer15276
AS6461Zayo BandwidthUSPeer13668
AS701Verizon BusinessUSPeer168

Prefixes

The largest blocks AS19043 originates, widest first.

Largest prefixes originated by AS19043
PrefixAddressesVisibility
205.134.128.0/198.2k76/76
205.134.132.0/2351276/76
205.134.128.0/2425676/76
205.134.158.0/2425676/76

Routing health

How AS19043's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid0.0%0
  • Invalid0.0%0
  • No ROA100.0%4

Propagation

  • Globally propagated90% of full-feed peers or more100.0%4
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 4 prefixes

Recent changes

Announcements that started or stopped since 24th Sept 2026.

No announcement by AS19043 started or stopped in this period.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.