asn.dev

Observed topology

AS203421 BALTICBROADBAND-AS

Residential RIPE Cable/DSL/ISP

Upstreams 18 carry this network
Downstreams 0 this network carries
Adjacent (IPv4) 18
Adjacent (IPv6) 0
Upstream graph Who carries AS203421, and who carries them, drawn as a map up to the transit-free core. 3 exchanges Where AS203421 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 18

Networks observed carrying traffic for AS203421: 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
AS51945ENLINK LTDUnclassifiedIPv487
AS61049Exascale LtdResidentialIPv449
AS6939Hurricane Electric LLCTransitIPv424
AS34549meerfarbig GmbH & Co. KGHostingIPv412
AS50304Blix Solutions ASUnclassifiedIPv48
AS3216PJSC "Vimpelcom"MobileIPv44
AS3741ISUnclassifiedIPv44
AS4657StarHub LtdResidentialIPv44
AS12552GlobalConnect ABUnclassifiedIPv44
AS12779IT.Gate S.p.A.UnclassifiedIPv44

All 18 upstreams →

Transit

Downstream networks

inferred

Networks for which AS203421 was observed as the last hop before the origin, meaning it appears to provide them transit.

No downstream observed. This network does not appear to carry transit for anyone.

Adjacency

Adjacent networks

All 18

Every AS seen directly next to AS203421 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS51945ENLINK LTDUnclassifiedIPv487
AS61049Exascale LtdResidentialIPv449
AS6939Hurricane Electric LLCTransitIPv424
AS34549meerfarbig GmbH & Co. KGHostingIPv412
AS50304Blix Solutions ASUnclassifiedIPv48
AS3216PJSC "Vimpelcom"MobileIPv44
AS3741ISUnclassifiedIPv44
AS4657StarHub LtdResidentialIPv44
AS12552GlobalConnect ABUnclassifiedIPv44
AS12779IT.Gate S.p.A.UnclassifiedIPv44

All 18 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-26 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.