asn.dev

Observed topology

AS25248 BLUETONE-AS The Czech Republic

Unclassified RIPE NSP

Upstreams 7 carry this network
Downstreams 27 this network carries
Adjacent (IPv4) 33
Adjacent (IPv6) 20
Upstream graph Who carries AS25248, and who carries them, drawn as a map up to the transit-free core. 3 exchanges Where AS25248 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS25248: 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 IPv6168
AS6939Hurricane Electric LLCTransitIPv4 IPv6106
AS174Cogent Communications, LLCTransitIPv4 IPv664
AS24482SG.GSHostingIPv4 IPv67
AS29504Freenet Liberec, z.s.UnclassifiedIPv4 IPv67
AS31230Slovak University of Technology in BratislavaUnclassifiedIPv45
AS37721Virtual Technologies & SolutionsResidentialIPv45

Transit

Downstream networks

All 27

Networks for which AS25248 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS206438MX-NET Telekomunikace s.r.o.UnclassifiedIPv4 IPv6521
AS47110Cloud4com s.r.o.HostingIPv4 IPv6315
AS206712FELDSAM s.r.o.UnclassifiedIPv4 IPv6282
AS204351NAM system, a.s.UnclassifiedIPv4114
AS213223GasNet, s.r.o.UnclassifiedIPv4111
AS215704NGN CZ s.r.o.UnclassifiedIPv4 IPv699
AS199600Virtis s.r.o.UnclassifiedIPv4 IPv694
AS213359Jan KorinekUnclassifiedIPv4 IPv694
AS59925Seonet Multimedia s.r.o.UnclassifiedIPv4 IPv693
AS39790Web4U s.r.o.HostingIPv490

All 27 downstreams →

Adjacency

Adjacent networks

All 34

Every AS seen directly next to AS25248 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS1299Arelion Sweden ABTransitIPv4 IPv61,281
AS6939Hurricane Electric LLCTransitIPv4 IPv61,132
AS174Cogent Communications, LLCTransitIPv4 IPv6630
AS206438MX-NET Telekomunikace s.r.o.UnclassifiedIPv4 IPv6521
AS47110Cloud4com s.r.o.HostingIPv4 IPv6318
AS206712FELDSAM s.r.o.UnclassifiedIPv4 IPv6282
AS25192CZ.NIC, z.s.p.o.UnclassifiedIPv4 IPv6224
AS204351NAM system, a.s.UnclassifiedIPv4114
AS213223GasNet, s.r.o.UnclassifiedIPv4111
AS215704NGN CZ s.r.o.UnclassifiedIPv4 IPv699

All 34 adjacent →

Provenance

Where this comes from

Derived from routing tables collected at 2026-10-22 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 73.12M 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.