asn.dev

Observed topology

AS25151 CYSO-AS Cyso Group B.V.

Hosting RIPE Content

Upstreams 29 carry this network
Downstreams 2 this network carries
Adjacent (IPv4) 23
Adjacent (IPv6) 17
Upstream graph Who carries AS25151, and who carries them, drawn as a map up to the transit-free core. 2 exchanges Where AS25151 physically turns up to peer, and its address on each fabric.

Transit

Upstream networks

All 29

Networks observed carrying traffic for AS25151: 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
AS3356Level 3 Parent, LLCTransitIPv4 IPv6414
AS1299Arelion Sweden ABTransitIPv4 IPv6144
AS2914NTT America, Inc.TransitIPv4 IPv6131
AS6939Hurricane Electric LLCTransitIPv627
AS50673Serverius Holding B.V.UnclassifiedIPv422
AS200020Stichting NBIP-NaWasUnclassifiedIPv422
AS42708Glesys Sweden ABUnclassifiedIPv4 IPv618
AS24482SG.GSHostingIPv4 IPv617
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv617
AS48185team.blue NVUnclassifiedIPv4 IPv617

All 29 upstreams →

Transit

Downstream networks

inferred

Networks for which AS25151 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS15535Virtual Access Internet BVHostingIPv459
AS210728Cyso Group B.V.UnclassifiedIPv420

Adjacency

Adjacent networks

All 31

Every AS seen directly next to AS25151 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS3356Level 3 Parent, LLCTransitIPv4 IPv6430
AS1299Arelion Sweden ABTransitIPv4 IPv6159
AS2914NTT America, Inc.TransitIPv4 IPv6150
AS15535Virtual Access Internet BVHostingIPv459
AS6939Hurricane Electric LLCTransitIPv627
AS50673Serverius Holding B.V.UnclassifiedIPv426
AS200020Stichting NBIP-NaWasUnclassifiedIPv422
AS42708Glesys Sweden ABUnclassifiedIPv4 IPv621
AS48185team.blue NVUnclassifiedIPv4 IPv620
AS210728Cyso Group B.V.UnclassifiedIPv420

All 31 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.