johnblackbourn.com
Observed Aug 16, 2026, 07:45 UTC (10h ago). Every field below was attested with an Ed25519 signature at scan time. Catalog observation, re-checked on rotation - watch it for 5-minute checks.
Up right now
Email byGoogle Workspace
Google WorkspaceSecured byLet's Encrypt
Let's EncryptRegistered withNameSilo, LLC
1 subdomain · domcop
Every line above is a signed observation. Check the math at the bottom of the page.
INFRASTRUCTURE MAPwhat johnblackbourn.com actually stands on - every host below is a signed observation
johnblackbourn.com
A / AAAA
75.2.60.5
unattributedserves the site
NS
ns1.dnsowl.comns2.dnsowl.comns3.dnsowl.com
dnsowl.comanswers its DNS
MX
alt1.aspmx.l.google.comalt2.aspmx.l.google.comalt3.aspmx.l.google.comalt4.aspmx.l.google.com+1 more
Google Workspacereceives its email
TLS
johnblackbourn.com
Let's Encryptissued its certificate
DNS Records
A 1
75.2.60.5
MX 5
5alt1.aspmx.l.google.com5alt2.aspmx.l.google.com10alt3.aspmx.l.google.com10alt4.aspmx.l.google.com1aspmx.l.google.com
TXT 1
v=spf1 a mx include:spf.mtasv.net ~all
NS 3
ns1.dnsowl.comns2.dnsowl.comns3.dnsowl.com
SOA 1
ns1.dnsowl.com hostmaster.dnsowl.com
TLS Certificates (4)
| Common Name | Issuer | Expires |
|---|---|---|
johnblackbourn.com |
C=US, O=Let's Encrypt, CN=YE1 | Sat, 19 Sep 2026 05:53:48 +0000 |
YE1 |
C=US, O=ISRG, CN=Root YE | Sat, 02 Sep 2028 23:59:59 +0000 |
Root YE |
C=US, O=Internet Security Research Group, CN=ISRG Root X2 | Thu, 02 Sep 2032 23:59:59 +0000 |
ISRG Root X2 |
C=US, O=Internet Security Research Group, CN=ISRG Root X1 | Thu, 02 Sep 2032 23:59:59 +0000 |
Subdomains (1)
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; the only network request the check makes is for the published public keys.
Verify this receiptEd25519 Receipt
- Receipt ID
rcpt_634236705c155085- Output Hash
8cca7037f93a645f266ead8e6677637e29c5bd92dde54abe6c780269f6c8c36c- Signature
ed25519:7b83cea5ed20691c412d932b81baa3c1a6ba2bfc00af79d96823314ece8376bb14b77c790f18a60b484b8a656ea55f84e1c14abceab1a4db5edea4d6e37ab501- Public Key
ed25519:4859bb613d650e12dd7478cc307c73a8712fabc115a9dc59f65534ed3c09a8f9- Parent
(genesis)- Plane
- fast