CESNET z.s.p.o.
AS2852 is CESNET z.s.p.o. (cesnet.cz). It announces 849,920 IPv4 addresses in 26 prefixes, and 1 IPv6 prefixes.
Czechia· RIPE· allocated 1993-12-20· education
Where its space is
The IPv4 it announces that IP Geolocation places, by country. A /24 counts for the AS announcing most of it.
- Czechia849,920 · 100.00%
Registry record
Its ASN Whois record, as the registry publishes it.
- handle
- CESNET2
- name
- CESNET z.s.p.o.
- org
- ORG-CA9-RIPE
- org name
- CESNET z.s.p.o.
- org address
- Generála Píky 430/26, Dejvice, 160 00, Praha 6, CZECH REPUBLIC
- org country
- CZ
- country
- CZ
- source
- ripe
- status
- ASSIGNED
- created
- 2002-06-22
- updated
- 2026-09-13
- remarks
- Transit networks / GEANT_IAS_VRF / CBF peerings / GEANT connection / AMS-IX peerings / ColocationIX GmbH / Packet Clearing House / CCBill / Telenor / BBC / NTT Communications / Golden telecom Moscow / RUNNET / Swisscom/IP-Plus / Packet Clearing House - peer / Virgin Media / Euronet NL / Atrato IP Networks / Atrato IP Networks - IPv6 / Shaw Cablesystems / EPT-LU / Euroweb Romania SA / EunetIP / EunetIP - IPv6 / Belgacom-ICS / Belgacom-ICS IPv6 / Telefonica Deutschland / Hurricane Electric, CA / Hurricane Ele
- maintainer
- RIPE-NCC-END-MNT|AS2852-MNT
- abuse name
- CESNET z.s.p.o. Network Administrators
- abuse email
- abuse@cesnet.cz
- abuse phone
- +420 602 252 531
- abuse kind
- role
What the databases see
Addresses each address-keyed database holds in the IPv4 it announces, as a share of that space, with its largest providers. Counts overlap.
- 0.00%
- geonode, privateproxy_me, anyip0.05%
- None here
- floppydata0.00%
- 0.00%
- None here
- Hosting IP16,3841.93%
- None here
- None here
- None here
- None here
- None here
- None here
IPv4 prefixes
Every IPv4 prefix BGP Route saw it announce. A prefix another AS also announces says so.
| PREFIX | COUNTRY | RPKI | PEERS | FIRST SEEN |
|---|---|---|---|---|
| 78.128.128.0/17 | Czechia | valid | 19 | 2026-10-02 |
| 146.102.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.32.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.33.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.228.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.230.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.231.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 147.251.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 158.194.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 158.196.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 160.216.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 160.217.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 185.8.160.0/22 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.32.0/20 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.53.0/24 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.55.0/24 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.56.0/21 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.80.0/22 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.104.0/22 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.116.0/23 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.160.0/20 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.192.0/19 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.192.0/20 | Czechia | valid | 19 | 2026-10-02 |
| 193.84.208.0/20 | Czechia | valid | 19 | 2026-10-02 |
| 195.113.0.0/16 | Czechia | valid | 19 | 2026-10-02 |
| 195.178.64.0/19 | Czechia | valid | 19 | 2026-10-02 |
IPv6 prefixes
Every IPv6 prefix BGP Route saw it announce.
| PREFIX | COUNTRY | RPKI | PEERS | FIRST SEEN |
|---|---|---|---|---|
| 2001:718::/29 | Czechia | valid | 20 | 2026-10-02 |
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