cas.cz

Observed 2026-07-04T19:46:16.502Z (7d ago). Every field below was attested with an Ed25519 signature at scan time.

INFRASTRUCTURE MAPwhat cas.cz actually stands on - every host below is a signed observation

cas.cz

A / AAAA

147.231.163.240

unattributedserves the site

academy.cas.czvisla.utia.cas.cznsa.ces.net

cas.cz + ces.netanswers its DNS

cas-cz.mail.protection.outlook.com

outlook.comreceives its email

HTTPS probe

redirect Redirecting (3xx) 301 → https://www.avcr.cz/

HTTP status301

Servercloudflare

TLS protocolHTTP/2

TLS issuernot observed

Behind Cloudflareyes

Response time1091 ms

DNS resolutionNOERROR

Redirect chain

https://www.avcr.cz/

Every field above is part of the same signed observation as the records below. Blank means not observed, never "none".

DNS Records

A 1

147.231.163.240

MX 1

10cas-cz.mail.protection.outlook.com

TXT 6

google-site-verification=vUDwTSfcIbP-SZlB4YtOHK9HptYiG6lYnU2bDgAbgqs
eZQUjdgG4Qz1lrWWUR2cbrxQzAfv6E8v5ZR6ERf7euQqDDSdKQQQ0MMjQLs5ERt6cGUN8tGMy8fMmLeoh4z5Ig==
MS=ms15273704
v=spf1 ip4:147.231.58.32 ip4:147.231.163.131 include:spf.protection.outlook.com ~all
PS-1DE9E9D695DD8C6BCB650BF86B69107D861F5A07
v=DNSSEC1; (detected)

NS 3

academy.cas.cz
visla.utia.cas.cz
nsa.ces.net

SOA 1

visla.utia.cas.cz root.utia.cas.cz

TLS Certificates (0)

None.

Subdomains (109)

The proof

Signed at scan time. Check the math yourself. Every line above is part of one signed observation. Re-hash it and check the Ed25519 signature in your own browser; nothing leaves your machine.

Verify this receipt

Put the receipt on your own site. A live badge showing what Connor observes and signs for cas.cz. It updates itself. It attests a signed observation - not that the site is safe.

<a href="https://connor.dns.drm3.network/t/cas.cz">
  <img src="https://connor.dns.drm3.network/badge/cas.cz.svg"
       width="300" height="64" alt="Connor signed observations for cas.cz">
</a>

Ed25519 Receipt

Receipt ID: d15df525-6b08-427e-9db7-02ddd19582e9
Output Hash: 0fad151933310ac4a47eeb805308d279e1a2bf8a667665d6acaf95216d97325e
Signature: ed25519:fd5667a6e1c866dc3baf93e720d04ff26732ce09cc08b9172e3d1378bf43eca714520a68a9e9daf3fa174dfb3aae23c4fb3804b30a730981cac52a4682893109
Public Key: ed25519:d610d74ef18f683e5beb859d241d5e67dff0c122e8928b06bec1c2476f4ba27b
Parent: (genesis)
Plane: fast

Verify this in your browser

Permalink: https://connor.dns.drm3.network/t/cas.cz/2026-07-04T19:46:16.502Z