asn.dev

Observed topology

AS12874 FASTWEB Fastweb SpA

Residential APNIC

Upstreams 18 carry this network
Downstreams 210 this network carries
Adjacent (IPv4) 229
Adjacent (IPv6) 48
Upstream graph Who carries AS12874, and who carries them, drawn as a map up to the transit-free core. 7 exchanges Where AS12874 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 18

Networks observed carrying traffic for AS12874: 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
AS3303Swisscom (Schweiz) AGResidentialIPv4 IPv62,323
AS1299Arelion Sweden ABTransitIPv4 IPv6913
AS3356Level 3 Parent, LLCTransitIPv4 IPv6818
AS9002RETN LimitedUnclassifiedIPv4 IPv6427
AS1273IDDQD-ASBusinessIPv4 IPv6386
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv6343
AS6461Zayo BandwidthTransitIPv4264
AS50673Serverius Holding B.V.UnclassifiedIPv4 IPv6207
AS6762TELECOM ITALIA SPARKLE S.p.A.TransitIPv4176
AS6939Hurricane Electric LLCTransitIPv4176

All 18 upstreams →

Transit

Downstream networks

All 210

Networks for which AS12874 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS44831Insiel- Informatica per il sistema degli enti locali S.p.AUnclassifiedIPv4 IPv62,459
AS25518Zucchetti SpaUnclassifiedIPv41,909
AS29312Comune di MilanoUnclassifiedIPv4860
AS197075Active Network S.p.A.ResidentialIPv4 IPv6841
AS48135Leonardo S.p.A.UnclassifiedIPv4759
AS15584Informatica Alto Adige SpaUnclassifiedIPv4612
AS21433Accenture UK LimitedUnclassifiedIPv4 IPv6605
AS201565ETRURIA WI-FI S.R.L.UnclassifiedIPv4 IPv6604
AS25301Sr Net S.R.L.UnclassifiedIPv4583
AS41160Amt Services srlUnclassifiedIPv4561

All 210 downstreams →

Adjacency

Adjacent networks

All 233

Every AS seen directly next to AS12874 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS3303Swisscom (Schweiz) AGResidentialIPv4 IPv618,812
AS3356Level 3 Parent, LLCTransitIPv4 IPv67,764
AS1299Arelion Sweden ABTransitIPv4 IPv66,856
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv62,633
AS44831Insiel- Informatica per il sistema degli enti locali S.p.AUnclassifiedIPv4 IPv62,459
AS25518Zucchetti SpaUnclassifiedIPv41,909
AS9002RETN LimitedUnclassifiedIPv4 IPv61,903
AS50673Serverius Holding B.V.UnclassifiedIPv4 IPv61,644
AS43976Poste Italiane S.p.A.UnclassifiedIPv41,028
AS6762TELECOM ITALIA SPARKLE S.p.A.TransitIPv4 IPv6976

All 233 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-11-10 10:00 UTC by route-views2,rrc00, as seen from 74 BGP vantage points across 71.97M 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.