subnet.im

AS51248Host-Telecom.com s.r.o.

CzechiaRegistryRIPE NCC

As of 11th November 2026, AS51248 (Host-Telecom.com s.r.o.), a network registered in Czechia with RIPE NCC, originates 22 IPv4 prefixes covering 14.6k addresses and 5 IPv6 prefixes. By IPv4 address space that makes it the 8,744th-largest of the 80,747 networks we see originating IPv4, and the 52nd-largest of 576 in Czechia. It is seen behind 14 upstream networks, most often AS9002 (RETN Limited) and AS1299 (Arelion (fka. Telia Carrier)), and in front of 7 downstream networks. 96% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. 96% of its routes reach at least 90% of full-feed peers, and 1 prefix is also originated by another network.

At a glance

IPv4 prefixes

22

IPv6 prefixes

5

IPv4 addresses

14.6k

IPv6 /64s

4.3B

Upstream graph

The networks AS51248 is seen behind, one and two hops out, drawn from real AS paths.

Networks observed one and two hops upstream of AS51248 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

80

adjacent networks

Upstreams
1418%
Peers
5974%
Downstreams
79%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS51248
NetworkCountryRelationshipPathsVantage pts
AS9002RETN LimitedGBPeer1,74171
AS1299Arelion (fka. Telia Carrier)SEPeer1,05531
AS3257GTT Communications Inc.USPeer54339
AS174Cogent Communications, LLCUSPeer43520
AS3223Voxility LLPGBPeer38776
AS6939Hurricane Electric LLCUSPeer27812
AS29208Quantcom, a.s.CZPeer22514
AS25091IP-Max SACHPeer862
AS32590Valve CorporationUSPeer762
AS24482SG.GSSGPeer662

Prefixes

All 27

The largest blocks AS51248 originates, widest first.

Largest prefixes originated by AS51248
PrefixAddressesVisibility
5.43.224.0/212k75/76
158.255.32.0/212k75/76
176.74.216.0/212k75/76
188.124.56.0/212k75/76
185.8.56.0/221k75/76
193.161.84.0/221k75/76
135.106.134.0/2351275/76
13.143.234.0/2425675/76
45.10.191.0/2425675/76
45.129.142.0/2425675/76

Routing health

How AS51248's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid96.3%26
  • Invalid0.0%0
  • No ROA3.7%1

Propagation

  • Globally propagated90% of full-feed peers or more96.3%26
  • Partially propagated40% to 90%3.7%1
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv6 — 5 prefixes

  • /324.3B × /6420.0%1
  • /4865.5k × /6480.0%4

Recent changes

Announcements that started or stopped since 12th Oct 2026.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.