asn.dev

Observed topology

AS1540 DNIC-ASBLK-01534-01546

Unclassified ARIN

Upstreams 3 carry this network
Downstreams 4 this network carries
Adjacent (IPv4) 7
Adjacent (IPv6) 4
Upstream graph Who carries AS1540, and who carries them, drawn as a map up to the transit-free core. 0 exchanges Where AS1540 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS1540: the AS immediately before it in a routing path. Ranked by how many paths showed the relationship, which reflects how widely it is used, not how much traffic crosses it.

ASNetworkTypeFamiliesPaths seen
AS27064United States Department of Defense (DoD)UnclassifiedIPv4 IPv687,083
AS27065United States Department of Defense (DoD)UnclassifiedIPv4 IPv628,790
AS367United States Department of Defense (DoD)UnclassifiedIPv4 IPv61,314

Transit

Downstream networks

inferred

Networks for which AS1540 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS306United States Department of Defense (DoD)UnclassifiedIPv4 IPv617,999
AS1493Headquarters, USAISCUnclassifiedIPv41,792
AS1554United States Department of Defense (DoD)UnclassifiedIPv41,474
AS588Headquarters, USAISCUnclassifiedIPv459

Adjacency

Adjacent networks

observed

Every AS seen directly next to AS1540 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS27064United States Department of Defense (DoD)UnclassifiedIPv4 IPv6173,004
AS306United States Department of Defense (DoD)UnclassifiedIPv4 IPv698,648
AS27065United States Department of Defense (DoD)UnclassifiedIPv4 IPv640,337
AS367United States Department of Defense (DoD)UnclassifiedIPv4 IPv616,363
AS1554United States Department of Defense (DoD)UnclassifiedIPv412,018
AS1493Headquarters, USAISCUnclassifiedIPv41,792
AS588Headquarters, USAISCUnclassifiedIPv459

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-21 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 73.14M route entries. These are observations from those vantage points, not a complete or authoritative view of the internet.

Inferred from path position, not from any declaration by either party. A network appearing here is carrying these routes; whether that is a paid transit arrangement, a backup, or something else is not something routing data can tell you. Adjacency is not the same as peering. Being next to each other in a path covers paid transit, settlement-free peering and customer connections alike, and routing data cannot distinguish them. Treat this as "these networks exchange routes", nothing more specific.

Cross-check against RIPEstat or BGP.tools, which observe from a different and larger set of vantage points.