subnet.im

AS51248Host-Telecom.com s.r.o.

CzechiaRegistryRIPE NCC

As of 27th September 2026, AS51248 (Host-Telecom.com s.r.o.), a network registered in Czechia with RIPE NCC, originates 19 IPv4 prefixes covering 13.8k addresses and 5 IPv6 prefixes. By IPv4 address space that makes it the 8,838th-largest of the 79,525 networks we see originating IPv4, and the 55th-largest of 574 in Czechia. It is seen behind 12 upstream networks, most often AS9002 (RETN Limited) and AS1299 (Arelion (fka. Telia Carrier)), and in front of 4 downstream networks. 96% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

19

IPv6 prefixes

5

IPv4 addresses

13.8k

IPv6 /64s

4.3B

Upstream graph

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

AS51248Toward the internet core
Upstream graph for AS51248: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS51248Host-Telecom.com …This networkAS174Cogent Communicat…AS1299Arelion (fka. Tel…AS3223Voxility LLPAS3257GTT Communication…AS9002RETN LimitedAS151326DCConnect Communi…AS8888xTom Pty LtdAS13030Init7 (Switzerlan…AS2914NTT America, Inc.AS3356Lumen (Level 3)AS6453TATA Communicatio…AS51907Kanton Zug

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

67

adjacent networks

Upstreams
1218%
Peers
5176%
Downstreams
46%

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

Upstreams of AS51248
NetworkCountryRelationshipPathsVantage pts
AS9002RETN LimitedGBPeer1,61370
AS1299Arelion (fka. Telia Carrier)SEPeer93138
AS174Cogent Communications, LLCUSPeer67131
AS3223Voxility LLPGBPeer50181
AS3257GTT Communications Inc.USPeer46821
AS6939Hurricane Electric LLCUSPeer29811
AS25091IP-Max SACHPeer952
AS32590Valve CorporationUSPeer592
AS24940Hetzner Online GmbHDEPeer592
AS49544i3D.net B.VNLPeer592

Prefixes

The largest blocks AS51248 originates, widest first.

Largest prefixes originated by AS51248
PrefixAddressesVisibility
5.43.224.0/212k81/81
158.255.32.0/212k81/81
176.74.216.0/212k81/81
188.124.56.0/212k81/81
185.8.56.0/221k81/81
193.161.84.0/221k81/81
135.106.134.0/2351281/81
13.143.234.0/2425680/81
45.10.191.0/2425681/81
45.129.142.0/2425680/81

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

  • Valid95.8%23
  • Invalid0.0%0
  • No ROA4.2%1

Propagation

  • Globally propagated90% of full-feed peers or more100.0%24
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 19 prefixes

IPv6 — 5 prefixes

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

Recent changes

Announcements that started or stopped since 28th Aug 2026.

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