asn.dev

Observed topology

AS1321 ANSBB-ASNNET-1

Upstreams 4 carry this network
Downstreams 12 this network carries
Adjacent (IPv4) 16
Adjacent (IPv6) 4

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS1321: 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
AS701Verizon BusinessResidentialIPv4 IPv6885
AS703Verizon BusinessUnclassifiedIPv4 IPv6306
AS702Verizon BusinessUnclassifiedIPv4 IPv6302
AS1339Verizon BusinessUnclassifiedIPv4 IPv693

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 AS1321 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS10953CONSTELLATION ENERGY GENERATION, LLCUnclassifiedIPv4869
AS26662XEROX CORPORATIONUnclassifiedIPv4660
AS22390XEROX CORPORATIONUnclassifiedIPv4660
AS4642Cathay Pacific Airways Ltd.UnclassifiedIPv4618
AS16224Verizon UK LimitedUnclassifiedIPv4598
AS7046Verizon BusinessUnclassifiedIPv4480
AS14799ExperianUnclassifiedIPv4339
AS26425Exelon CorporationUnclassifiedIPv4259
AS2830Verizon Nederland B.V.UnclassifiedIPv4238
AS11787Supreme Court of PennsylvaniaUnclassifiedIPv4218
AS23503Exelon CorporationUnclassifiedIPv4204
AS395959XEROX CORPORATIONUnclassifiedIPv4180

Adjacency

Adjacent networks

20 shown

Every AS seen directly next to AS1321 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS701Verizon BusinessResidentialIPv4 IPv63,467
AS702Verizon BusinessUnclassifiedIPv4 IPv62,575
AS703Verizon BusinessUnclassifiedIPv4 IPv6883
AS10953CONSTELLATION ENERGY GENERATION, LLCUnclassifiedIPv4869
AS26662XEROX CORPORATIONUnclassifiedIPv4660
AS22390XEROX CORPORATIONUnclassifiedIPv4660
AS4642Cathay Pacific Airways Ltd.UnclassifiedIPv4618
AS16224Verizon UK LimitedUnclassifiedIPv4598
AS7046Verizon BusinessUnclassifiedIPv4480
AS14799ExperianUnclassifiedIPv4339
AS23503Exelon CorporationUnclassifiedIPv4300
AS26425Exelon CorporationUnclassifiedIPv4272
AS2830Verizon Nederland B.V.UnclassifiedIPv4238
AS11787Supreme Court of PennsylvaniaUnclassifiedIPv4218
AS395959XEROX CORPORATIONUnclassifiedIPv4180
AS1339Verizon BusinessUnclassifiedIPv4 IPv693

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 AS1321, 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.