asn.dev

Observed topology

AS43037 SEZNAM-

Hosting RIPE Content

Upstreams 23 carry this network
Downstreams 1 this network carries
Adjacent (IPv4) 21
Adjacent (IPv6) 18
Upstream graph Who carries AS43037, and who carries them, drawn as a map up to the transit-free core. 2 exchanges Where AS43037 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 23

Networks observed carrying traffic for AS43037: 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
AS1299Arelion Sweden ABTransitIPv4 IPv6213
AS6939Hurricane Electric LLCTransitIPv4 IPv6106
AS29208Quantcom, a.s.UnclassifiedIPv4 IPv629
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv629
AS5610O2 Czech Republic, a.s.UnclassifiedIPv4 IPv627
AS1836green.ch AGResidentialIPv4 IPv612
AS24482SG.GSHostingIPv4 IPv612
AS29504Freenet Liberec, z.s.UnclassifiedIPv4 IPv612
AS34019Hivane AssociationUnclassifiedIPv4 IPv612
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv612

All 23 upstreams →

Transit

Downstream networks

inferred

Networks for which AS43037 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS200600Seznam.cz datova centra, s.r.o.HostingIPv4 IPv694

Adjacency

Adjacent networks

All 24

Every AS seen directly next to AS43037 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS1299Arelion Sweden ABTransitIPv4 IPv6251
AS6939Hurricane Electric LLCTransitIPv4 IPv6121
AS200600Seznam.cz datova centra, s.r.o.HostingIPv4 IPv694
AS29208Quantcom, a.s.UnclassifiedIPv4 IPv634
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv634
AS5610O2 Czech Republic, a.s.UnclassifiedIPv4 IPv630
AS1836green.ch AGResidentialIPv4 IPv614
AS24482SG.GSHostingIPv4 IPv614
AS29504Freenet Liberec, z.s.UnclassifiedIPv4 IPv614
AS34019Hivane AssociationUnclassifiedIPv4 IPv614

All 24 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-29 10:00 UTC by route-views2,rrc00, as seen from 76 BGP vantage points across 74.36M 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.