asn.dev

Observed topology

AS399855 KEYSTONEREN

Unclassified ARIN

Upstreams 4 carry this network
Downstreams 28 this network carries
Adjacent (IPv4) 32
Adjacent (IPv6) 9
Upstream graph Who carries AS399855, and who carries them, drawn as a map up to the transit-free core. 0 exchanges Where AS399855 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS399855: 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
AS396955Internet2UnclassifiedIPv439
AS6939Hurricane Electric LLCTransitIPv4 IPv629
AS11164Internet2EducationIPv4 IPv613
AS11537Internet2UnclassifiedIPv412

Transit

Downstream networks

All 28

Networks for which AS399855 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS22644Thomas Jefferson University Hospitals, Inc.UnclassifiedIPv4 IPv6272
AS3999The Pennsylvania State UniversityEducationIPv4 IPv6119
AS9Carnegie Mellon UniversityUnclassifiedIPv4 IPv698
AS398564Pennsylvania Western UniversityUnclassifiedIPv497
AS398663Shippensburg UniversityUnclassifiedIPv4 IPv693
AS7150Commonwealth University of PennsylvaniaEducationIPv470
AS398813Millersville University of PennsylvaniaUnclassifiedIPv470
AS397913East Stroudsburg University of PennsylvaniaUnclassifiedIPv460
AS394170Susquehanna UniversityUnclassifiedIPv455
AS31746Franklin and Marshall CollegeUnclassifiedIPv454

All 28 downstreams →

Adjacency

Adjacent networks

All 32

Every AS seen directly next to AS399855 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS11537Internet2UnclassifiedIPv4 IPv6662
AS6939Hurricane Electric LLCTransitIPv4 IPv6471
AS11164Internet2EducationIPv4 IPv6356
AS22644Thomas Jefferson University Hospitals, Inc.UnclassifiedIPv4 IPv6272
AS398663Shippensburg UniversityUnclassifiedIPv4 IPv6152
AS3999The Pennsylvania State UniversityEducationIPv4 IPv6119
AS9Carnegie Mellon UniversityUnclassifiedIPv4 IPv698
AS398564Pennsylvania Western UniversityUnclassifiedIPv497
AS7150Commonwealth University of PennsylvaniaEducationIPv470
AS398813Millersville University of PennsylvaniaUnclassifiedIPv470

All 32 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-19 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 73.17M 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.