asn.dev

Observed topology

AS18671 PRTC-SC

Upstreams 3 carry this network
Downstreams 3 this network carries
Adjacent (IPv4) 6
Adjacent (IPv6) 0

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS18671: 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
AS16863Home Telephone Company, Inc.UnclassifiedIPv41,103
AS2711Spirit CommunicationsUnclassifiedIPv4628
AS26744Planters Communications, LLCUnclassifiedIPv4358

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 AS18671 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS14480County of OrangeburgUnclassifiedIPv4432
AS398766TriCoLink, Inc.UnclassifiedIPv4172
AS23087Communications Data GroupUnclassifiedIPv459

Adjacency

Adjacent networks

6 shown

Every AS seen directly next to AS18671 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS16863Home Telephone Company, Inc.UnclassifiedIPv41,161
AS26744Planters Communications, LLCUnclassifiedIPv4921
AS2711Spirit CommunicationsUnclassifiedIPv4697
AS14480County of OrangeburgUnclassifiedIPv4432
AS398766TriCoLink, Inc.UnclassifiedIPv4199
AS23087Communications Data GroupUnclassifiedIPv459

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 AS18671, 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.

No exchange membership on file. That is not the same as peering nowhere: the dataset records what PCH has collected, and many exchanges publish no participant list at all.

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.