asn.dev

Observed topology

AS21738 ROZINT - Rozint

Residential ARIN Cable/DSL/ISP

Upstreams 6 carry this network
Downstreams 27 this network carries
Adjacent (IPv4) 22
Adjacent (IPv6) 27
Upstream graph Who carries AS21738, and who carries them, drawn as a map up to the transit-free core. 2 exchanges Where AS21738 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS21738: 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
AS6939Hurricane Electric LLCTransitIPv4 IPv6323
AS32097WholeSale Internet, Inc.HostingIPv4234
AS1299Arelion Sweden ABTransitIPv497
AS3257GTT Communications Inc.TransitIPv441
AS34927iFog GmbHHostingIPv67
AS52025ParadoxNetworks LimitedUnclassifiedIPv45

Transit

Downstream networks

All 27

Networks for which AS21738 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS402247flew llcHostingIPv4 IPv6223
AS6517LAKENETWORKSHostingIPv4 IPv6187
AS401710CloudMesh Labs LLCUnclassifiedIPv4 IPv6152
AS53388Tefexia LCUnclassifiedIPv4 IPv6130
AS14923Graham Technology Solutions LLCUnclassifiedIPv4 IPv693
AS151349Yuki Network LtdHostingIPv4 IPv686
AS398549Zero Attack Vector LLCUnclassifiedIPv4 IPv676
AS214430Takahiro FukushimaUnclassifiedIPv672
AS200242Ember Ana ReimerUnclassifiedIPv668
AS270142Castor Networks MexicoUnclassifiedIPv458

All 27 downstreams →

Adjacency

Adjacent networks

All 34

Every AS seen directly next to AS21738 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS6939Hurricane Electric LLCTransitIPv4 IPv61,511
AS32097WholeSale Internet, Inc.HostingIPv4 IPv6902
AS402247flew llcHostingIPv4 IPv6223
AS6517LAKENETWORKSHostingIPv4 IPv6217
AS401710CloudMesh Labs LLCUnclassifiedIPv4 IPv6152
AS151349Yuki Network LtdHostingIPv4 IPv6139
AS53388Tefexia LCUnclassifiedIPv4 IPv6130
AS1299Arelion Sweden ABTransitIPv4 IPv6108
AS14923Graham Technology Solutions LLCUnclassifiedIPv4 IPv693
AS398549Zero Attack Vector LLCUnclassifiedIPv4 IPv676

All 34 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-11-11 10:00 UTC by route-views2,rrc00, as seen from 74 BGP vantage points across 73.24M 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.