asn.dev

Observed topology

AS201789 NETOPS

Upstreams 8 carry this network
Downstreams 4 this network carries
Adjacent (IPv4) 13
Adjacent (IPv6) 10

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS201789: 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
AS50673Serverius Holding B.V.UnclassifiedIPv4123
AS6939Hurricane Electric LLCTransitIPv4 IPv671
AS9002RETN LimitedUnclassifiedIPv4 IPv645
AS174Cogent Communications, LLCTransitIPv4 IPv623
AS59900Balkan Internet Exchange LtdUnclassifiedIPv4 IPv622
AS24482SG.GSHostingIPv41
AS48362Stadtwerke FeldkirchResidentialIPv41
AS1836green.ch AGResidentialIPv41

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 AS201789 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS51430AltusHost B.V.UnclassifiedIPv4 IPv62,417
AS136787PacketHub S.A.VPNIPv4254
AS61295NETOPS B.V.UnclassifiedIPv4 IPv6104
AS207604United Internet Ltd.UnclassifiedIPv461

Adjacency

Adjacent networks

23 shown

Every AS seen directly next to AS201789 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS51430AltusHost B.V.UnclassifiedIPv4 IPv62,417
AS12459NETOPS B.V.HostingIPv4 IPv61,084
AS6939Hurricane Electric LLCTransitIPv4 IPv6908
AS9002RETN LimitedUnclassifiedIPv4 IPv6418
AS50673Serverius Holding B.V.UnclassifiedIPv4 IPv6402
AS136787PacketHub S.A.VPNIPv4254
AS174Cogent Communications, LLCTransitIPv4 IPv6170
AS59900Balkan Internet Exchange LtdUnclassifiedIPv4 IPv6104
AS61295NETOPS B.V.UnclassifiedIPv4 IPv6104
AS207604United Internet Ltd.UnclassifiedIPv461
AS1836green.ch AGResidentialIPv4 IPv618
AS24482SG.GSHostingIPv4 IPv618
AS48362Stadtwerke FeldkirchResidentialIPv41

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 AS201789, 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 3 exchanges across 2 countries and 1 region.

ExchangeLocationTheir addressMember ports
SwissIXZurich, Switzerland91.206.52.224253
Bulgarian Internet eXchangeSofia, Bulgaria193.169.199.72137
Balkan Internet ExchangeSofia, Bulgaria185.1.30.14767

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 2026-08-08 by Packet Clearing House (https://www.pch.net/ixp/data), covering 1,327 exchanges and 93,137 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.