asn.dev

Observed topology

AS21453 FLEX-AS

Residential RIPE

Upstreams 15 carry this network
Downstreams 12 this network carries
Adjacent (IPv4) 28
Adjacent (IPv6) 12
Upstream graph Who carries AS21453, and who carries them, drawn as a map up to the transit-free core. 1 exchange Where AS21453 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 15

Networks observed carrying traffic for AS21453: 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
AS12389PJSC RostelecomResidentialIPv4 IPv6339
AS35598INETCOM CARRIER LLCUnclassifiedIPv4226
AS20764CJSC RASCOMUnclassifiedIPv4109
AS1299Arelion Sweden ABTransitIPv4 IPv6106
AS57304JSC "RetnNet"UnclassifiedIPv4 IPv686
AS28917Fiord Networks, UABUnclassifiedIPv4 IPv683
AS8641LLC "Nauka-Svyaz"UnclassifiedIPv4 IPv646
AS62255BiMajLink d.o.o.UnclassifiedIPv436
AS29076Citytelecom LLCHostingIPv629
AS24482SG.GSHostingIPv4 IPv619

All 15 upstreams →

Transit

Downstream networks

All 12

Networks for which AS21453 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS48149Ivanteevskie telecommunicacii LtdUnclassifiedIPv4 IPv6292
AS34975Azimut-R Ltd.UnclassifiedIPv4189
AS201646Flex-l LtdUnclassifiedIPv4 IPv6163
AS57489LLC "Telecom-Uslugi"UnclassifiedIPv4145
AS43567UG-TELECOM Ltd.UnclassifiedIPv4100
AS41783Informational technologies and electronic communications LLCUnclassifiedIPv4 IPv699
AS35271JSC "AVIEL"UnclassifiedIPv4 IPv643
AS50449Limited Liability Company "Kvant"UnclassifiedIPv438
AS49893Bitrace telecom Ltd.UnclassifiedIPv432
AS216335OOO Kalibr SBUnclassifiedIPv428

All 12 downstreams →

Adjacency

Adjacent networks

All 29

Every AS seen directly next to AS21453 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS12389PJSC RostelecomResidentialIPv4 IPv6811
AS35598INETCOM CARRIER LLCUnclassifiedIPv4308
AS48149Ivanteevskie telecommunicacii LtdUnclassifiedIPv4 IPv6299
AS28917Fiord Networks, UABUnclassifiedIPv4 IPv6225
AS1299Arelion Sweden ABTransitIPv4 IPv6210
AS20764CJSC RASCOMUnclassifiedIPv4197
AS34975Azimut-R Ltd.UnclassifiedIPv4189
AS8641LLC "Nauka-Svyaz"UnclassifiedIPv4 IPv6175
AS201646Flex-l LtdUnclassifiedIPv4 IPv6163
AS49893Bitrace telecom Ltd.UnclassifiedIPv4158

All 29 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-24 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 72.94M 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.