asn.dev

Observed topology

AS18403 FPT-VN - FPT Telecom Company

Residential APNIC

Upstreams 50 carry this network
Downstreams 236 this network carries
Adjacent (IPv4) 283
Adjacent (IPv6) 127
Upstream graph Who carries AS18403, and who carries them, drawn as a map up to the transit-free core. 16 exchanges Where AS18403 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 50

Networks observed carrying traffic for AS18403: 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 IPv640,189
AS3356Level 3 Parent, LLCTransitIPv4 IPv617,307
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv612,059
AS1299Arelion Sweden ABTransitIPv4 IPv68,837
AS24482SG.GSHostingIPv4 IPv68,403
AS38001NewMedia Express Pte LtdHostingIPv4 IPv68,401
AS33891Core-Backbone GmbHHostingIPv4 IPv65,485
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv65,254
AS1836green.ch AGResidentialIPv4 IPv65,202
AS48362Stadtwerke FeldkirchResidentialIPv4 IPv65,168

All 50 upstreams →

Transit

Downstream networks

All 236

Networks for which AS18403 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS140766FPT Smart Cloud Company LimitedUnclassifiedIPv4 IPv66,929
AS135918VIET DIGITAL TECHNOLOGY LIABILITY COMPANYUnclassifiedIPv4 IPv63,861
AS140815HTTVSERVER TECHNOLOGY COMPANY LIMITEDUnclassifiedIPv4 IPv62,817
AS150895EZ TECHNOLOGY COMPANY LIMITEDUnclassifiedIPv4 IPv62,243
AS38244VNG CorporationUnclassifiedIPv4 IPv61,916
AS45894FPT Online JSCUnclassifiedIPv4 IPv61,765
AS131429MOBIFONE CorporationUnclassifiedIPv4 IPv61,383
AS151858INTERDIGI JOINT STOCK COMPANYUnclassifiedIPv4 IPv61,373
AS140810Megacore Technology Company LimitedUnclassifiedIPv4 IPv61,294
AS150698Chandpur Online SystemsUnclassifiedIPv4 IPv61,251

All 236 downstreams →

Adjacency

Adjacent networks

All 298

Every AS seen directly next to AS18403 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS6939Hurricane Electric LLCTransitIPv4 IPv646,656
AS1299Arelion Sweden ABTransitIPv4 IPv626,506
AS3356Level 3 Parent, LLCTransitIPv4 IPv623,746
AS4637Telstra GlobalUnclassifiedIPv4 IPv616,149
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv615,565
AS38001NewMedia Express Pte LtdHostingIPv4 IPv69,997
AS24482SG.GSHostingIPv4 IPv69,681
AS135918VIET DIGITAL TECHNOLOGY LIABILITY COMPANYUnclassifiedIPv4 IPv68,618
AS140766FPT Smart Cloud Company LimitedUnclassifiedIPv4 IPv66,951
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv66,278

All 298 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-11-08 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 73.00M 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.