asn.dev

Observed topology

AS42541 FIBERBY Fiberby ApS

Residential RIPE Cable/DSL/ISP

Upstreams 32 carry this network
Downstreams 5 this network carries
Adjacent (IPv4) 35
Adjacent (IPv6) 21
Upstream graph Who carries AS42541, and who carries them, drawn as a map up to the transit-free core. 5 exchanges Where AS42541 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 32

Networks observed carrying traffic for AS42541: 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
AS3356Level 3 Parent, LLCTransitIPv4 IPv6122
AS6939Hurricane Electric LLCTransitIPv4 IPv650
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv611
AS1299Arelion Sweden ABTransitIPv410
AS3333Reseaux IP Europeens Network Coordination Centre (RIPE NCC)UnclassifiedIPv4 IPv66
AS17639Converge ICT Solutions Inc.UnclassifiedIPv4 IPv66
AS24482SG.GSHostingIPv4 IPv66
AS42708Glesys ABUnclassifiedIPv4 IPv66
AS48185team.blue NVUnclassifiedIPv4 IPv66
AS48362Stadtwerke FeldkirchResidentialIPv4 IPv66

All 32 upstreams →

Transit

Downstream networks

inferred

Networks for which AS42541 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS207727Asbjorn Sloth Tonnesen trading as a5nUnclassifiedIPv4 IPv6303
AS204141K-Net ForeningUnclassifiedIPv4 IPv6155
AS205235LabitatUnclassifiedIPv4 IPv6133
AS201697Tobias Fonsmark trading as SemaphorUnclassifiedIPv4 IPv6127
AS12654Reseaux IP Europeens Network Coordination Centre (RIPE NCC)UnclassifiedIPv4 IPv68

Adjacency

Adjacent networks

All 38

Every AS seen directly next to AS42541 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS205235LabitatUnclassifiedIPv4 IPv6734
AS6939Hurricane Electric LLCTransitIPv4 IPv6545
AS3356Level 3 Parent, LLCTransitIPv4 IPv6338
AS207727Asbjorn Sloth Tonnesen trading as a5nUnclassifiedIPv4 IPv6303
AS204141K-Net ForeningUnclassifiedIPv4 IPv6155
AS201697Tobias Fonsmark trading as SemaphorUnclassifiedIPv4 IPv6127
AS1299Arelion Sweden ABTransitIPv453
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv652
AS401753BIXCE IncUnclassifiedIPv4 IPv644
AS3333Reseaux IP Europeens Network Coordination Centre (RIPE NCC)UnclassifiedIPv4 IPv640

All 38 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-11-05 10:00 UTC by route-views2,rrc00, as seen from 76 BGP vantage points across 73.57M 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.