AS57728 CEZNET s.r.o.

Czechia CEZNET-AS RIPE 5 IPv4 prefixes 3 IPv6 prefixes

IPv4 addresses

15,360

IPv6 /48 networks

196,608

RPKI

8 valid0 no ROA

Peers and downstreams

Holder

AS name: CEZNET-AS
Description: CEZNET s.r.o.
Organisation: CEZNET s.r.o.
Abuse contact: dohled@ceznet.cz
Assigned: 2019-10-20
Registered: 2019-10-21
Record last changed: 2025-09-26 09:55 UTC

109.234.40.0/21 185.255.116.0/22 188.122.192.0/19 81.25.16.0/21 81.25.24.0/21

Upstream graph

Upstreams and their upstreams, from BGP paths

Network health

Grade A · 95/100

pass	Prefixes covered by valid ROAs 8 of 8 announced prefixes are RPKI valid.	25/25
pass	No RPKI invalid announcements None of the announcements is RPKI invalid.	10/10
pass	Announces IPv6 3 IPv6 prefixes.	15/15
partly	More than one upstream 1 upstream seen in BGP.	5/10
pass	Working abuse contact dohled@ceznet.cz is published.	15/15
pass	Publishes a geofeed A geofeed (RFC 8805) tells where the address space is used.	10/10
pass	No prefixes smaller than /24 or /48 All prefixes are /24 (IPv4) or /48 (IPv6) or larger.	10/10
pass	Registry record maintained Last changed 2025-09-26.	5/5

Built from the announced prefixes, RPKI, the registry record and geofeeds. Checks without data are not counted. Also in the API.

Show this on your website

HTML

<a href="https://ip-fd.net/asn/57728"><img src="https://ip-fd.net/badge/asn/57728/health.svg" alt="AS57728 network health on IP-FD.net"></a>

Markdown

[![AS57728 network health](https://ip-fd.net/badge/asn/57728/health.svg)](https://ip-fd.net/asn/57728)

Use rpki.svg instead of health.svg for the RPKI badge.

Routing changes

Last 30 days

No changes recorded in the last 30 days. Changes are recorded each time the routing data of this AS is refreshed. Get alerts in real time.

WHOIS

aut-num:        AS57728
as-name:        CEZNET-AS
org:            ORG-TBS13-RIPE
remarks:        ---- NIX.CZ ----
remarks:        ---- PEERING.CZ ----
remarks:        ---- Telia ----
remarks:        ---- TPS ----
remarks:        ---- Superhosting.cz ----
remarks:        ---- Cerberos ----
remarks:        ---- 4NET ----
remarks:        ---- CSC ----
remarks:        ---- UPC ----
admin-c:        CH13482-RIPE
tech-c:         CH13482-RIPE
status:         ASSIGNED
mnt-by:         RIPE-NCC-END-MNT
mnt-by:         CEZNET-MNT
created:        2019-10-21T06:50:54Z
last-modified:  2025-09-26T09:55:20Z
source:         RIPE
% 18 routing policy lines (import/export) not shown

Routing data

Updated just now

Registry record

Fetched just now from RIPE

Prefixes and neighbours come from the RIPE RIS route collectors. Data older than 5 minutes is refreshed when this page is opened.

API

curl -H "X-API-Key: YOUR_KEY" https://ip-fd.net/api/v1/asn/57728

const res = await fetch('https://ip-fd.net/api/v1/asn/57728', {
  headers: { 'X-API-Key': 'YOUR_KEY' }
});
const data = await res.json();
console.log(data);

import requests

r = requests.get('https://ip-fd.net/api/v1/asn/57728', headers={'X-API-Key': 'YOUR_KEY'}, timeout=10)
r.raise_for_status()
print(r.json())

<?php
$ch = curl_init('https://ip-fd.net/api/v1/asn/57728');
curl_setopt($ch, CURLOPT_HTTPHEADER, ['X-API-Key: YOUR_KEY']);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$data = json_decode(curl_exec($ch), true);
print_r($data);

req, _ := http.NewRequest("GET", "https://ip-fd.net/api/v1/asn/57728", nil)
req.Header.Set("X-API-Key", "YOUR_KEY")
res, err := http.DefaultClient.Do(req)
if err != nil {
    log.Fatal(err)
}
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

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