asn.dev

Observed topology

AS51907 CH-ZG

Upstreams 32 carry this network
Downstreams 2 this network carries
Adjacent (IPv4) 28
Adjacent (IPv6) 16

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS51907: 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
AS39040NTS workspace AGUnclassifiedIPv4 IPv625
AS9002RETN LimitedUnclassifiedIPv4 IPv621
AS34288Kantonsschule ZugUnclassifiedIPv4 IPv621
AS15576NTS workspace AGUnclassifiedIPv4 IPv617
AS6939Hurricane Electric LLCTransitIPv412
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv69
AS50673Serverius Holding B.V.UnclassifiedIPv44
AS50304Blix Solutions ASUnclassifiedIPv44
AS211452Kanton Appenzell AusserrhodenUnclassifiedIPv64
AS24482SG.GSHostingIPv4 IPv63
AS48185team.blue NVUnclassifiedIPv4 IPv63
AS212024Marc SchmittUnclassifiedIPv4 IPv63
AS3333Reseaux IP Europeens Network Coordination Centre (RIPE NCC)UnclassifiedIPv4 IPv63
AS50300CustodianDC LimitedUnclassifiedIPv4 IPv63
AS17639Converge ICT Solutions Inc.UnclassifiedIPv4 IPv63
AS8434Telenor Sverige ABResidentialIPv42
AS20485Joint Stock Company TransTeleComUnclassifiedIPv42
AS29632Netassist International EOODUnclassifiedIPv62
AS3303Swisscom (Schweiz) AGResidentialIPv42
AS37100SEACOM LimitedUnclassifiedIPv42
AS3741Dimension DataUnclassifiedIPv42
AS6730Sunrise GmbHMobileIPv42
AS37721Virtual Technologies & SolutionsResidentialIPv42
AS1836green.ch AGResidentialIPv42
AS48362Stadtwerke FeldkirchResidentialIPv42
AS20766Association "Gitoyen"UnclassifiedIPv42
AS56655Gigahost ASUnclassifiedIPv42
AS12552GlobalConnect ABUnclassifiedIPv41
AS34019Hivane AssociationUnclassifiedIPv61
AS56662Marcin GondekUnclassifiedIPv61
AS293ESnetUnclassifiedIPv41
AS213241TECHIT.BE SRLResidentialIPv61

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 AS51907 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS34288Kantonsschule ZugUnclassifiedIPv4 IPv667
AS211452Kanton Appenzell AusserrhodenUnclassifiedIPv49

Adjacency

Adjacent networks

46 shown

Every AS seen directly next to AS51907 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS34288Kantonsschule ZugUnclassifiedIPv4 IPv6123
AS39040NTS workspace AGUnclassifiedIPv4 IPv6101
AS211452Kanton Appenzell AusserrhodenUnclassifiedIPv4 IPv639
AS9002RETN LimitedUnclassifiedIPv4 IPv621
AS15576NTS workspace AGUnclassifiedIPv4 IPv617
AS6939Hurricane Electric LLCTransitIPv412
AS6730Sunrise GmbHMobileIPv49
AS34549meerfarbig GmbH & Co. KGHostingIPv4 IPv69
AS50304Blix Solutions ASUnclassifiedIPv44
AS50673Serverius Holding B.V.UnclassifiedIPv44
AS37721Virtual Technologies & SolutionsResidentialIPv43
AS37100SEACOM LimitedUnclassifiedIPv43
AS3333Reseaux IP Europeens Network Coordination Centre (RIPE NCC)UnclassifiedIPv4 IPv63
AS24482SG.GSHostingIPv4 IPv63
AS48185team.blue NVUnclassifiedIPv4 IPv63
AS17639Converge ICT Solutions Inc.UnclassifiedIPv4 IPv63
AS50300CustodianDC LimitedUnclassifiedIPv4 IPv63
AS212024Marc SchmittUnclassifiedIPv4 IPv63
AS3303Swisscom (Schweiz) AGResidentialIPv42
AS3741Dimension DataUnclassifiedIPv42
AS20485Joint Stock Company TransTeleComUnclassifiedIPv42
AS1836green.ch AGResidentialIPv42
AS48362Stadtwerke FeldkirchResidentialIPv42
AS56655Gigahost ASUnclassifiedIPv42
AS8434Telenor Sverige ABResidentialIPv42
AS20766Association "Gitoyen"UnclassifiedIPv42
AS29632Netassist International EOODUnclassifiedIPv62
AS34019Hivane AssociationUnclassifiedIPv61
AS213241TECHIT.BE SRLResidentialIPv61
AS56662Marcin GondekUnclassifiedIPv61
AS12552GlobalConnect ABUnclassifiedIPv41
AS293ESnetUnclassifiedIPv41

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 AS51907, 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 4 exchanges across 4 countries and 1 region.

ExchangeLocationTheir addressMember ports
DE-CIX FrankfurtFrankfurt, Germany80.81.196.2061,073
LINX LON1London, United Kingdom195.66.228.96925
AMS-IX AmsterdamAmsterdam, Netherlands80.249.215.69894
SwissIXZurich, Switzerland91.206.53.40253

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.