CESNET z.s.p.o.
Cluster stats
Netblocks303
All fragments 371 blocks across 46 clusters
Cluster ID191597209
RegistryBGP
Customersfind customers using this network →
Evidence & provenance ?
Attribution unresolved
Shared handles clustered on 10 shared RIR contact/maintainer handles
Registry names 3 distinct registrant names across these blocks
full provenance (JSON) → · how attribution works

Footprint over time

2 weekly snapshots · JSON
303 0 netblocks since 2026-07-05
2026-07-05 peak 303 2026-07-06

IP Ranges (303)

showing 50 of 303 — see all — ⬇ export CSV
CIDR Org name Registry Status Confidence
78.128.128.0/17 CESNET z.s.p.o. BGP ANNOUNCED ● high
78.128.235.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● high
146.102.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.32.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.33.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.228.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.230.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.231.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
147.251.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
158.194.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
158.196.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
160.216.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
160.217.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
185.8.160.0/22 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.32.0/20 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.53.0/24 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.55.0/24 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.56.0/21 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.80.0/22 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.104.0/22 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.116.0/23 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.160.0/20 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.192.0/20 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.192.0/19 CESNET z.s.p.o. BGP ANNOUNCED ● high
193.84.208.0/20 CESNET z.s.p.o. BGP ANNOUNCED ● high
195.113.0.0/16 CESNET z.s.p.o. BGP ANNOUNCED ● high
195.113.167.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● high
195.178.64.0/19 CESNET z.s.p.o. BGP ANNOUNCED ● high
2001:718::/29 CESNET z.s.p.o. BGP ANNOUNCED ● high
78.128.128.0/17 CESNET z.s.p.o. RIPE ALLOCATED PA ● low
78.128.210.0/25 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.211.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.212.0/26 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.212.64/26 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.214.0/26 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.214.70/31 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.214.128/27 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.214.192/26 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.216.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.217.128/27 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.217.224/27 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.0/26 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.64/28 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.80/29 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.88/31 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.90/31 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.112/28 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.218.128/25 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.219.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● low
78.128.222.0/24 CESNET z.s.p.o. RIPE ASSIGNED PA ● low

Network trust

what's this?
RPKI hygiene: A how networks compare →
100.0% of checked blocks have valid RPKI ROA coverage (303 of 303)
Possible discrepancies (1)

These blocks are registered to CESNET z.s.p.o. but cryptographically authorized for a different, unrelated network (1 distinct holder) — often M&A history, multi-homing, or outsourced/managed hosting, occasionally worth a closer look.

194.212.11.0/24 /24 authorized for AS13036 — T-Mobile Czech Republic a.s.

NIC Handles

AS2852 CZMC1-RIPE DUMY-RIPE DUMY-RIPE GTSCZ-MNT ORG-CA9-RIPE RIPE-NCC-END-MNT RIPE-NCC-HM-MNT TENCZ-MNT TENCZ-MNT