asn.dev

Observed topology

AS25577 C4L-AS

Upstreams 24 carry this network
Downstreams 8 this network carries
Adjacent (IPv4) 34
Adjacent (IPv6) 7

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS25577: 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
AS174Cogent Communications, LLCTransitIPv41,048
AS3257GTT Communications Inc.TransitIPv4 IPv6613
AS6939Hurricane Electric LLCTransitIPv4 IPv6442
AS34549meerfarbig GmbH & Co. KGHostingIPv4180
AS3223Voxility LLPHostingIPv4122
AS50304Blix Solutions ASUnclassifiedIPv490
AS48185team.blue NVUnclassifiedIPv450
AS12552GlobalConnect ABUnclassifiedIPv449
AS3303Swisscom (Schweiz) AGResidentialIPv448
AS29169GANDI SASHostingIPv448
AS24482SG.GSHostingIPv4 IPv648
AS50300CustodianDC LimitedUnclassifiedIPv447
AS57463NetIX Communications JSCUnclassifiedIPv447
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv647
AS7575Australian Academic and Research Network (AARNet)EducationIPv445
AS37100SEACOM LimitedUnclassifiedIPv445
AS3741Dimension DataUnclassifiedIPv445
AS48362Stadtwerke FeldkirchResidentialIPv445
AS12779IT.Gate S.p.A.UnclassifiedIPv445
AS17639Converge ICT Solutions Inc.UnclassifiedIPv445
AS31500Global Network Management IncUnclassifiedIPv445
AS4637Telstra GlobalUnclassifiedIPv43
AS9505Taiwan Internet GatewayUnclassifiedIPv43
AS8218Zayo Infrastructure France SAUnclassifiedIPv42

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.

Transit

Downstream networks

inferred

Networks for which AS25577 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS31708Coreix LtdHostingIPv4 IPv61,448
AS203035Xara Computers (UK) LtdUnclassifiedIPv499
AS44934Arachsys Internet Services LtdUnclassifiedIPv4 IPv695
AS59493Cudo Ventures LtdUnclassifiedIPv4 IPv694
AS51572Cerulean Solutions LimitedUnclassifiedIPv460
AS50882Maxnett Ltd.UnclassifiedIPv460
AS206626Professional Software Design LtdUnclassifiedIPv42
AS207162L3C LimitedUnclassifiedIPv41

Adjacency

Adjacent networks

41 shown

Every AS seen directly next to AS25577 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS31708Coreix LtdHostingIPv4 IPv62,325
AS174Cogent Communications, LLCTransitIPv41,946
AS3257GTT Communications Inc.TransitIPv4 IPv61,114
AS6939Hurricane Electric LLCTransitIPv4 IPv6901
AS34549meerfarbig GmbH & Co. KGHostingIPv4315
AS50304Blix Solutions ASUnclassifiedIPv4182
AS3223Voxility LLPHostingIPv4122
AS24482SG.GSHostingIPv4 IPv6104
AS37721Virtual Technologies & SolutionsResidentialIPv4 IPv6104
AS203035Xara Computers (UK) LtdUnclassifiedIPv499
AS48185team.blue NVUnclassifiedIPv495
AS44934Arachsys Internet Services LtdUnclassifiedIPv4 IPv695
AS57463NetIX Communications JSCUnclassifiedIPv494
AS12552GlobalConnect ABUnclassifiedIPv494
AS59493Cudo Ventures LtdUnclassifiedIPv4 IPv694
AS29169GANDI SASHostingIPv492
AS7575Australian Academic and Research Network (AARNet)EducationIPv491
AS48362Stadtwerke FeldkirchResidentialIPv491
AS50300CustodianDC LimitedUnclassifiedIPv489
AS17639Converge ICT Solutions Inc.UnclassifiedIPv489
AS37100SEACOM LimitedUnclassifiedIPv488
AS3741Dimension DataUnclassifiedIPv488
AS12779IT.Gate S.p.A.UnclassifiedIPv486
AS31500Global Network Management IncUnclassifiedIPv483
AS50882Maxnett Ltd.UnclassifiedIPv468
AS3303Swisscom (Schweiz) AGResidentialIPv462
AS51572Cerulean Solutions LimitedUnclassifiedIPv460
AS13237euNetworks GmbHUnclassifiedIPv45
AS9505Taiwan Internet GatewayUnclassifiedIPv43
AS20562Broadband Hosting B.V.HostingIPv43
AS4637Telstra GlobalUnclassifiedIPv43
AS206626Professional Software Design LtdUnclassifiedIPv42
AS8218Zayo Infrastructure France SAUnclassifiedIPv42
AS207162L3C LimitedUnclassifiedIPv41

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.

Interconnection

Exchange presence

recorded

Internet exchanges where Packet Clearing House has a port recorded for AS25577, largest fabric first. An exchange is shared switching where networks interconnect directly rather than paying a transit provider to carry traffic between them, so turning up at one is a deliberate choice about how this network wants to be reached. Each name opens that exchange's own page, with its peering LANs and every other network recorded on it. Recorded at 2 exchanges across 1 country and 1 region.

ExchangeLocationTheir addressMember ports
LINX LON1London, United Kingdom195.66.224.201925
London Network Access PointLondon, United Kingdom5.57.80.217316

Unlike the tables above, this is recorded rather than inferred. An address on a peering LAN is at that exchange by definition. Two carve-outs all the same. Member ports counts every participant at the exchange, not this network's ports, so read it as a size proxy. And an absent exchange means PCH has no record of it, not that the network is not there.

Provenance

Where this comes from

Derived from routing tables collected at 2026-08-08 10:00 UTC by route-views2,rrc00, as seen from 75 BGP vantage points across 74.02M route entries. These are observations from those vantage points, not a complete or authoritative view of the internet.

Cross-check against RIPEstat or BGP.tools, which observe from a different and larger set of vantage points.

Exchange presence comes from a separate dataset: the directory collected 2026-08-09 by Packet Clearing House (https://www.pch.net/ixp/data), covering 1,327 exchanges and 93,164 recorded member ports, licensed CC BY-NC-SA 3.0.

PeeringDB is the better-known directory and is deliberately not the source here: its acceptable-use policy forbids the bulk storage this needs. The two answer different questions anyway. PeeringDB reports what an operator declares about itself; this reports what PCH has recorded.