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AS2721CULR, LLC

United StatesRegistryARIN

As of 24th October 2026, AS2721 (CULR, LLC), a network registered in the United States with ARIN, originates 5 IPv4 prefixes covering 9.2k addresses and 1 IPv6 prefix. 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 6 upstream networks, most often AS174 (Cogent Communications, LLC) and AS11164 (Internet2 I2PX), and in front of 4 downstream networks. None of its announcements have a valid RPKI ROA. 50% of its routes reach at least 90% of full-feed peers, and 1 prefix is also originated by another network.

At a glance

IPv4 prefixes

5

IPv6 prefixes

1

IPv4 addresses

9.2k

IPv6 /64s

4.3B

Upstream graph

The networks AS2721 is seen behind, one and two hops out, drawn from real AS paths.

AS2721Toward the internet core
Upstream graph for AS2721: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS2721CULR, LLCThis networkAS174Cogent Communicat…AS2711Spirit Communicat…AS3257GTT Communication…AS11164Internet2 I2PXAS11537Internet2AS151326DCConnect Communi…AS1299Arelion (fka. Tel…AS2914NTT America, Inc.AS6667Elisa OyjAS398465Rackdog LLCAS2152CENIC - CalRENAS2497Internet Initiati…

Networks observed one and two hops upstream of AS2721 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

21

adjacent networks

Upstreams
629%
Peers
1152%
Downstreams
419%

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

Upstreams of AS2721
NetworkCountryRelationshipPathsVantage pts
AS174Cogent Communications, LLCUSPeer64767
AS11164Internet2 I2PXUSPeer33167
AS3257GTT Communications Inc.USPeer18658
AS2711Spirit CommunicationsUSPeer7326
AS11537Internet2USPeer382
AS2722CULR, LLCUSPeer266

Prefixes

The largest blocks AS2721 originates, widest first.

Largest prefixes originated by AS2721
PrefixAddressesVisibility
205.186.224.0/198.2k75/76
192.188.108.0/2425672/76
205.186.46.0/2425632/76
205.186.47.0/2425635/76
205.186.226.0/2425675/76
2606:c000::/324.3B × /6433/63

Routing health

How AS2721'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%6

Propagation

  • Globally propagated90% of full-feed peers or more50.0%3
  • Partially propagated40% to 90%50.0%3
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 5 prefixes

IPv6 — 1 prefixes

  • /324.3B × /64100.0%1

Recent changes

Announcements that started or stopped since 24th Sept 2026.

No announcement by AS2721 started or stopped in this period.

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