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AS1540Headquarters, USAISC

United StatesRegistryARIN

As of 22nd October 2026, AS1540 (Headquarters, USAISC), a network registered in the United States with ARIN, originates 2,000 IPv4 prefixes covering 8.4M addresses and 64 IPv6 prefixes. By IPv4 address space that makes it the 81st-largest of the 79,655 networks we see originating IPv4, and the 25th-largest of 18,475 in the United States. It is seen behind 3 upstream networks, most often AS27064 (Defense Information Systems Agency…) and AS27065 (United States Department of Defense…), and in front of 6 downstream networks. 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

2,000

IPv6 prefixes

64

IPv4 addresses

8.4M

IPv6 /64s

4.2M

Upstream graph

The networks AS1540 is seen behind, one and two hops out, drawn from real AS paths.

AS1540Toward the internet core
Upstream graph for AS1540: 4 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS1540Headquarters, USA…This networkAS367United States Dep…AS27064Defense Informati…AS27065United States Dep…AS721United States Dep…

Networks observed one and two hops upstream of AS1540 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

16

adjacent networks

Upstreams
319%
Peers
744%
Downstreams
638%

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

Upstreams of AS1540
NetworkCountryRelationshipPathsVantage pts
AS27064Defense Information Systems Agency (DISA)USPeer230,226140
AS27065United States Department of Defense (DoD)USPeer53,779140
AS367United States Department of Defense (DoD)USPeer21,953140

Prefixes

All 2,064

The largest blocks AS1540 originates, widest first.

Largest prefixes originated by AS1540
PrefixAddressesVisibility
6.240.0.0/121M76/77
6.248.0.0/13524k76/77
6.244.0.0/14262k77/77
6.140.0.0/15131k77/77
146.14.0.0/15131k77/77
6.41.0.0/1665.5k77/77
6.68.0.0/1665.5k77/77
55.196.0.0/1665.5k77/77
128.190.0.0/1665.5k77/77
129.29.0.0/1665.5k77/77

Routing health

How AS1540'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%2,064

Propagation

  • Globally propagated90% of full-feed peers or more100.0%2,064
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 2,000 prefixes

IPv6 — 64 prefixes

  • /4865.5k × /64100.0%64

Recent changes

Announcements that started or stopped since 22nd Sept 2026.

1,066 announced and 262 withdrawn in all; the most recent are shown.

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