Observed topology

AS12145 COLORADOSTATEUNIV - Colorado State University

Unclassified ARIN

Upstreams 1 carry this network

Downstreams 5 this network carries

Adjacent (IPv4) 6

Adjacent (IPv6) 0

Upstream graph Who carries AS12145, and who carries them, drawn as a map up to the transit-free core. 0 exchanges Where AS12145 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS12145: 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.

AS	Network	Type	Families	Paths seen
AS14041	University Corporation for Atmospheric Research	Education	IPv4	75

Transit

Downstream networks

inferred

Networks for which AS12145 was observed as the last hop before the origin, meaning it appears to provide them transit.

AS	Network	Type	Families	Paths seen
AS394748	City of Fort Collins	Unclassified	IPv4	186
AS54669	Larimer County Government	Unclassified	IPv4	62
AS31991	Platte River Power Authority	Unclassified	IPv4	59
AS54060	Poudre School District R-1	Unclassified	IPv4	9
AS25825	Poudre Valley Health Care, Inc.	Unclassified	IPv4	4

Adjacency

Adjacent networks

observed

Every AS seen directly next to AS12145 in a routing path, in either direction.

AS	Network	Type	Families	Paths seen
AS14041	University Corporation for Atmospheric Research	Education	IPv4	395
AS394748	City of Fort Collins	Unclassified	IPv4	186
AS54669	Larimer County Government	Unclassified	IPv4	62
AS31991	Platte River Power Authority	Unclassified	IPv4	59
AS54060	Poudre School District R-1	Unclassified	IPv4	9
AS25825	Poudre Valley Health Care, Inc.	Unclassified	IPv4	4

Provenance

Where this comes from

Derived from routing tables collected at 2026-11-11 10:00 UTC by route-views2,rrc00, as seen from 74 BGP vantage points across 73.24M 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.