asn.dev

Observed topology

AS16246 AS16246 NEJ.cz s.r.o

Upstreams 1 carry this network
Downstreams 13 this network carries
Adjacent (IPv4) 13
Adjacent (IPv6) 13

Transit

Upstream networks

inferred

Networks observed carrying traffic for AS16246: 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
AS5610O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6858

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 AS16246 was observed as the last hop before the origin, meaning it appears to provide them transit.

ASNetworkTypeFamiliesPaths seen
AS12570O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6725
AS62178MASTER IT Technologies, a.s.UnclassifiedIPv4 IPv6658
AS41046O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6548
AS31246O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6372
AS29321O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6328
AS212315Frantisek TomanUnclassifiedIPv4 IPv6214
AS44070O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6156
AS49767O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6153
AS197197CETIN a.s.UnclassifiedIPv4 IPv695
AS202657Pavel JochimUnclassifiedIPv4 IPv693
AS207015Position s.r.o.UnclassifiedIPv4 IPv683
AS47681O2 Czech Republic, a.s.UnclassifiedIPv460
AS39736ICT Support, s.r.o.UnclassifiedIPv626

Adjacency

Adjacent networks

29 shown

Every AS seen directly next to AS16246 in a routing path, in either direction.

ASNetworkTypeFamiliesPaths seen
AS5610O2 Czech Republic, a.s.UnclassifiedIPv4 IPv65,404
AS12570O2 Czech Republic, a.s.UnclassifiedIPv4 IPv61,731
AS62178MASTER IT Technologies, a.s.UnclassifiedIPv4 IPv6689
AS41046O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6548
AS31246O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6372
AS29321O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6328
AS212315Frantisek TomanUnclassifiedIPv4 IPv6214
AS44070O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6156
AS49767O2 Czech Republic, a.s.UnclassifiedIPv4 IPv6153
AS197197CETIN a.s.UnclassifiedIPv4 IPv695
AS202657Pavel JochimUnclassifiedIPv4 IPv693
AS207015Position s.r.o.UnclassifiedIPv4 IPv683
AS47681O2 Czech Republic, a.s.UnclassifiedIPv460
AS39736ICT Support, s.r.o.UnclassifiedIPv626

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 AS16246, 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 1 exchange across 1 country and 1 region.

ExchangeLocationTheir addressMember ports
Peering.czPrague, Czech Republic185.0.20.16212

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.