asn.dev

Observed topology

AS40401 BACKBLAZE

Hosting APNIC Content

Upstreams 36 carry this network
Downstreams 1 this network carries
Adjacent (IPv4) 27
Adjacent (IPv6) 25
Upstream graph Who carries AS40401, and who carries them, drawn as a map up to the transit-free core. 5 exchanges Where AS40401 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 36

Networks observed carrying traffic for AS40401: 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 IPv61,322
AS3257GTT Communications Inc.TransitIPv4 IPv6596
AS6939Hurricane Electric LLCTransitIPv4 IPv6518
AS3356Level 3 Parent, LLCTransitIPv4 IPv6306
AS812Rogers Communications Canada Inc.MobileIPv4 IPv6139
AS24482SG.GSHostingIPv4 IPv678
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv628
AS293ESnetUnclassifiedIPv423
AS4637Telstra GlobalUnclassifiedIPv420
AS1403EBOXResidentialIPv618

All 36 upstreams →

Transit

Downstream networks

inferred

Networks for which AS40401 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS396865Backblaze IncUnclassifiedIPv4 IPv691

Adjacency

Adjacent networks

All 37

Every AS seen directly next to AS40401 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS1299Arelion Sweden ABTransitIPv4 IPv61,362
AS3257GTT Communications Inc.TransitIPv4 IPv6610
AS6939Hurricane Electric LLCTransitIPv4 IPv6533
AS3356Level 3 Parent, LLCTransitIPv4 IPv6327
AS812Rogers Communications Canada Inc.MobileIPv4 IPv6139
AS396865Backblaze IncUnclassifiedIPv4 IPv691
AS24482SG.GSHostingIPv4 IPv679
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv628
AS293ESnetUnclassifiedIPv423
AS4637Telstra GlobalUnclassifiedIPv420

All 37 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-23 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 73.15M 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.