asn.dev

Observed topology

AS21320 GEANT_IAS_VRF GEANT Vereniging

Unclassified RIPE

Upstreams 9 carry this network
Downstreams 40 this network carries
Adjacent (IPv4) 53
Adjacent (IPv6) 43
Upstream graph Who carries AS21320, and who carries them, drawn as a map up to the transit-free core. 19 exchanges Where AS21320 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS21320: 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, LLCTransitIPv421
AS2603NORDUnetEducationIPv414
AS174Cogent Communications, LLCTransitIPv49
AS6939Hurricane Electric LLCTransitIPv47
AS9002RETN LimitedUnclassifiedIPv45
AS3216PJSC "Vimpelcom"MobileIPv41
AS3303Swisscom (Schweiz) AGResidentialIPv41
AS8551Bezeq International Ltd.UnclassifiedIPv41
AS48185team.blue NVUnclassifiedIPv41

Transit

Downstream networks

All 40

Networks for which AS21320 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS1930Fundacao para a Ciencia e a Tecnologia, I.P.UnclassifiedIPv4 IPv63,755
AS378Israel InterUniversity Computation CenterUnclassifiedIPv4 IPv62,019
AS5408National Infrastructures for Research and Technology S.A.EducationIPv4 IPv61,356
AS2614Agentia de Administrare a Retelei Nationale de Informatica pentru Educatie si CercetareEducationIPv4 IPv61,224
AS2607Zdruzenie pouzivatelov Slovenskej akademickej datovej siete SANETEducationIPv4 IPv6879
AS6802Bulgarian Research and Education Network Association (BREN)EducationIPv4 IPv6852
AS2200RenaterEducationIPv4 IPv6818
AS6879ENSTINETEducationIPv4789
AS766Entidad Publica Empresarial Red.esUnclassifiedIPv4 IPv6638
AS2107ARNESUnclassifiedIPv4 IPv6613

All 40 downstreams →

Adjacency

Adjacent networks

All 54

Every AS seen directly next to AS21320 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS2603NORDUnetEducationIPv4 IPv615,121
AS5408National Infrastructures for Research and Technology S.A.EducationIPv4 IPv66,592
AS3356Level 3 Parent, LLCTransitIPv4 IPv64,956
AS1930Fundacao para a Ciencia e a Tecnologia, I.P.UnclassifiedIPv4 IPv64,708
AS174Cogent Communications, LLCTransitIPv4 IPv63,105
AS766Entidad Publica Empresarial Red.esUnclassifiedIPv4 IPv62,627
AS2200RenaterEducationIPv4 IPv62,556
AS6939Hurricane Electric LLCTransitIPv4 IPv62,531
AS9002RETN LimitedUnclassifiedIPv4 IPv62,326
AS378Israel InterUniversity Computation CenterUnclassifiedIPv4 IPv62,073

All 54 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.