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Registry Zone Health Intelligence — co.uk is a shared registry suffix.
This report focuses on zone infrastructure health: DNSSEC signing, nameserver diversity, certificate authority policy, and delegation security. Email authentication protocols (SPF, DMARC, DKIM) are not applicable to registry suffixes — they apply to domains registered under this zone.
Registry operators, ICANN, and ccTLD authorities can use this view to assess zone security posture.
DNS Tool
Registry Zone Health Report
Generated 24 Feb 2026, 14:58 UTC
Duration 44.5s
Version v26.25.65
Integrity 3f119cafd66c385cda88e8a6c572b6733d22b6728ae20f8121190e9e6c539ea3882a350a0036bc562f99d7915fdbfede9846e772d9c1566a5bc437821996c697
Subject Domain
co.uk

Registry Zone Health Report

co.uk
24 Feb 2026, 14:58 UTC · 44.5s ·v26.25.65 · SHA-3-512: 3f11✱✱✱✱ Verify
Executive Methodology
Recon Mode Snapshot Re-analyze New Domain
Footprint
Intelligence Currency
Data Currency: Adequate 68/100
ICuAE Details
Currentness Excellent TTL Compliance Excellent Completeness Stale Source Credibility Excellent TTL Relevance Degraded
DNS data shows some aging or gaps — consider re-scanning for critical decisions

The following DNS record TTLs deviate from recommended values. Incorrect TTLs can cause caching issues, slow propagation, or unnecessary DNS traffic.

Record Type Observed TTL Typical TTL Severity Context
SOA 21564s 1 hour (3600s) high SOA TTL is above — observed 21564s, typical value is 1 hour (3600s). Consider setting to 3600 seconds per NIST SP 800-53 SI-18 relevance guidance.
NS 21584s 1 day (86400s) medium NS TTL is below — observed 21584s, typical value is 1 day (86400s). Consider setting to 86400 seconds per NIST SP 800-53 SI-18 relevance guidance.

Big Picture Questions

  • How often do you actually change this record? If it hasn’t changed in months, a short TTL is generating unnecessary DNS queries without any benefit.
  • Are you preparing for a migration or IP change? Short TTLs make sense temporarily — but should be raised back to 1 hour (3600s) once the change is complete.
  • Every DNS lookup adds 20–150ms of latency. With a 60s TTL, returning visitors trigger a fresh lookup every minute. With 3600s, they get cached responses for an hour — faster page loads, no extra infrastructure needed.
  • Google runs A records at ~30s because they operate a global anycast network and need to steer traffic dynamically. For a typical website without that infrastructure, copying those TTLs increases query volume with zero upside.
Tune TTL for co.uk
Reference: NIST SP 800-53 SI-7 (Information Integrity) · RFC 8767 (Serve Stale) · RFC 1035 §3.2.1 (TTL semantics)
Suggested Scanner Configuration High Confidence
Based on 19 historical scans of this domain
Parameter Current Suggested Severity Rationale
timeout_seconds 5s 8s low Average scan duration is 45.8s, suggesting DNS responses are slow for this domain. Increasing timeout from 5s to 8s prevents premature resolution failures.
RFC 8767
Suggestions require explicit approval before applying. No automatic changes will be made.
Registry Zone Health
DNSSEC: Success CAA: Not Set 0 Nameservers
Zone infrastructure protocols applicable to registry suffixes
Email Spoofing
Vulnerable
Brand Impersonation
Not Setup
DNS Tampering
Protected
Certificate Control
Open
Action Required
No SPF and no DMARC — domain is completely unprotected against email spoofing
Recommended
Publish an SPF record to authorize legitimate mail senders, Publish a DMARC record starting with p=none and rua reporting
Monitoring
DKIM signing inferred from provider — could not directly verify selector
Configured
DKIM (inferred via Unknown), DNSSEC
Not Configured
SPF, DMARC, MTA-STS, TLS-RPT, BIMI, DANE, CAA
Priority Actions Achievable posture: Low Risk
High Add DMARC Reject for No-Mail Domain

This domain has no MX records and appears to be a website-only domain. A DMARC reject policy tells receiving mail servers to reject any email claiming to be from your domain.

Instructs receiving servers to reject all email from this domain — no legitimate mail is expected.
TypeTXT
Host_dmarc.co.uk
Valuev=DMARC1; p=reject; sp=reject; adkim=s; aspf=s;
RFC 7489
High Lock Down SPF for No-Mail Domain

This domain has no MX records and appears to be a website-only domain. Publishing a strict SPF record explicitly declares that no servers are authorized to send email, preventing attackers from spoofing your domain.

Explicitly declares no servers are authorized to send email from this domain.
TypeTXT
Hostco.uk
Valuev=spf1 -all
RFC 7208
Low Add CAA Records

CAA records specify which Certificate Authorities may issue certificates for your domain, reducing the risk of unauthorized certificate issuance.

CAA constrains which CAs can issue certificates for this domain.
TypeCAA
Hostco.uk (root of domain — adjust CA to match your provider)
Value0 issue "letsencrypt.org"
RFC 8659
Registrar (RDAP) LIVE
Unknown
Where domain was purchased
Email Service Provider
Unknown
Unprotected
Web Hosting
Unknown
Where website is hosted
DNS Hosting
Unknown
Where DNS records are edited
DNS Server Security Hardened

No DNS server misconfigurations found on nsc.nic.uk — Nmap NSE probes for zone transfer (AXFR), open recursion (RFC 5358), nameserver identity disclosure, and DNS cache snooping.

Check Result Detail
Zone Transfer (AXFR) Denied Zone transfer denied (correct configuration)
Open Recursion Disabled Recursion disabled (correct configuration)
Nameserver Identity Hidden No nameserver identity information disclosed
Cache Snooping Protected Cache snooping not possible (correct configuration)

Tested nameservers: nsc.nic.uk, dns1.nic.uk, nsa.nic.uk, dns3.nic.uk, dns2.nic.uk, nsd.nic.uk, dns4.nic.uk, nsb.nic.uk

Zone Signing & DNSSEC Methodology Is this zone cryptographically signed? YES DNSSEC signed and validated, cryptographic chain of trust verified

DNSSEC RFC 4033 §2 Verified Signed RSA/SHA-256 Adequate

DNSSEC fully configured and validated — AD (Authenticated Data) flag set by resolver 8.8.8.8 confirming cryptographic chain of trust from root to zone (RFC 4035 §3.2.3)

Algorithm Observation: RSA/SHA-256 — MUST implement, widely deployed (RFC 8624 §3.1)
All current DNSSEC algorithms use classical cryptography. Post-quantum DNSSEC standards are in active IETF development (draft-sheth-pqc-dnssec-strategy) but no PQC algorithms have been standardized for DNSSEC yet.
Chain of trust: Root → TLD → Domain. DNS responses are authenticated and tamper-proof.
AD Flag: Validated - Resolver (8.8.8.8) confirmed cryptographic signatures
DS Record (at registrar):
11810 8 2 1DF4681BDACC3E6296AC7667C42CA33CB57EFBC2005CE23064F15FBFFA286FF5

NS Delegation Verified Match

NS delegation verified - 8 nameserver(s) match parent zone

Parent zone delegation matches domain's NS records. No delegation drift detected.
Nameservers: dns1.nic.uk dns2.nic.uk dns3.nic.uk dns4.nic.uk nsa.nic.uk nsb.nic.uk nsc.nic.uk nsd.nic.uk
Multi-Resolver Verification Recon: Consensus reached - 5 resolvers (Cloudflare, Google, Quad9, OpenDNS, DNS4EU) agree on DNS records

CDS / CDNSKEY (DNSSEC Automation) RFC 7344 Success CDS CDNSKEY

Full RFC 8078 automated DNSSEC key rollover signaling detected (CDS + CDNSKEY)

Key TagAlgorithmDigest TypeDigest
11810 RSASHA256 2
CDNSKEY Records:
FlagsProtocolAlgorithmPublic Key
257 3 RSASHA256
Subdomain Discovery Not Applicable
Certificate Transparency subdomain enumeration is not applicable for registry suffixes. For co.uk, CT logs would show registered domains under this zone rather than organizational subdomains. To analyze a specific domain's exposure, scan a registrable domain like example.co.uk.
Δ Changes Detected: SOA Resolver ≠ Authoritative (TTL / CDN rotation / recent change)
Risk: Low - typically resolves within TTL
DNS Intelligence What does DNS look like right now — and what changed over time?
DNS Evidence Diff Side-by-side comparison
Resolver Records (Public DNS cache)
Authoritative Records (Source of truth)
A 0 / 0 records
No records
No records
AAAA 0 / 0 records
No records
No records
CAA RFC 8659 §4 0 / 0 records
No records
No records
MX RFC 5321 0 / 0 records
No records
No records
NS RFC 1035 Synchronized 8 / 8 records
dns4.nic.uk.
nsb.nic.uk.
nsa.nic.uk.
dns2.nic.uk.
dns3.nic.uk.
nsa.nic.uk.
nsc.nic.uk.
dns4.nic.uk.
nsb.nic.uk.
nsc.nic.uk.
dns1.nic.uk.
dns1.nic.uk.
dns2.nic.uk.
nsd.nic.uk.
nsd.nic.uk.
dns3.nic.uk.
SOA RFC 1035 Propagating 1 / 1 records
dns1.nic.uk. hostmaster.nominet.org.uk. 1771944976 900 300 2419200 10800
dns1.nic.uk. hostmaster.nominet.org.uk. 1771945006 900 300 2419200 10800
TXT RFC 7208 §4 0 / 0 records
No records
No records
DNS History Timeline BETA

When was a record added, removed, or changed — and could that change be the problem?

Analyze Another Domain

DATA FRESHNESS & METHODOLOGY

All security-critical records (SPF, DMARC, DKIM, DANE/TLSA, DNSSEC, MTA-STS, TLS-RPT, BIMI, CAA) are queried live from authoritative nameservers and cross-referenced against 5 independent public DNS resolvers (Cloudflare, Google, Quad9, OpenDNS, DNS4EU) at the time of each analysis. No security verdict uses cached data.

Registrar data (RDAP) is cached for up to 24 hours because domain ownership and registration details change infrequently. Certificate Transparency logs (subdomain discovery via RFC 6962) are cached for 1 hour because CT entries are append-only historical records. Sections using cached data are marked with a CACHED badge; live queries show LIVE.

Intelligence Sources

This analysis used 4 DNS resolvers (consensus), reverse DNS (PTR), Team Cymru (ASN attribution), IANA RDAP (registrar), crt.sh (CT logs), and SMTP probing (transport). All using open-standard protocols.

Full List
Verify Report Integrity SHA-3-512 Has this report been altered since generation? Verify below

This cryptographic hash seals the analysis data, domain, timestamp, and tool version into a tamper-evident fingerprint. Any modification to the report data will produce a different hash. This is distinct from the posture hash (used for drift detection) — the integrity hash uniquely identifies this specific report instance.

3f119cafd66c385cda88e8a6c572b6733d22b6728ae20f8121190e9e6c539ea3882a350a0036bc562f99d7915fdbfede9846e772d9c1566a5bc437821996c697
Evaluations reference 12 RFCs. Methods are reproducible using the verification commands provided. Results reflect DNS state at 24 Feb 2026, 14:58 UTC.
Download Raw Intelligence Download Checksum (.sha3)

Download the intelligence dump and verify its integrity, like you would a Kali ISO or any critical artifact. The SHA-3-512 checksum covers every byte of the download — deterministic serialization ensures identical hashes across downloads.

After downloading, verify with any of these commands:

Tip: cd ~/Downloads first (or wherever you saved the files).

OpenSSL + Sidecar (macOS, Linux, WSL) 
cat dns-intelligence-co.uk.json.sha3 && echo '---' && openssl dgst -sha3-512 dns-intelligence-co.uk.json
Python 3 (cross-platform) 
python3 -c "import hashlib; print(hashlib.sha3_512(open('dns-intelligence-co.uk.json','rb').read()).hexdigest())"
sha3sum (coreutils 9+) 
sha3sum -a 512 dns-intelligence-co.uk.json
Compare the output against the .sha3 file or the checksum API at /api/analysis/4161/checksum. Hash algorithm: SHA-3-512 (Keccak, NIST FIPS 202).

Every finding in this report is backed by DNS queries you can run yourself. These vetted one-liners reproduce the exact checks used to build this report for co.uk. Our analysis adds multi-resolver consensus, RFC-based evaluation, and cross-referencing — but the underlying data is always independently verifiable. We are intelligence analysts, not gatekeepers.

DNS Records

Query A records (IPv4) RFC 1035 
dig +noall +answer co.uk A
Query AAAA records (IPv6) RFC 1035 
dig +noall +answer co.uk AAAA
Query MX records (mail servers) RFC 1035 
dig +noall +answer co.uk MX
Query NS records (nameservers) RFC 1035 
dig +noall +answer co.uk NS
Query TXT records RFC 1035 
dig +noall +answer co.uk TXT

Email Authentication

Check SPF record RFC 7208 
dig +short co.uk TXT | grep -i spf
Check DMARC policy RFC 7489 
dig +short _dmarc.co.uk TXT
Check DKIM key for selector 'default' RFC 6376 
dig +short default._domainkey.co.uk TXT
Check DKIM key for selector 'google' RFC 6376 
dig +short google._domainkey.co.uk TXT
Check DKIM key for selector 'selector1' RFC 6376 
dig +short selector1._domainkey.co.uk TXT
Check DKIM key for selector 'selector2' RFC 6376 
dig +short selector2._domainkey.co.uk TXT

Domain Security

Check DNSSEC DNSKEY records RFC 4035 
dig +dnssec +noall +answer co.uk DNSKEY
Check DNSSEC DS records RFC 4035 
dig +noall +answer co.uk DS
Validate DNSSEC chain (requires DNSSEC-validating resolver) RFC 4035 
dig +dnssec +cd co.uk A @1.1.1.1

Transport Security

Check TLSA record (replace MX_HOST with actual MX) RFC 7672 
dig +noall +answer _25._tcp.MX_HOST TLSA
Check MTA-STS DNS record RFC 8461 
dig +short _mta-sts.co.uk TXT
Fetch MTA-STS policy file RFC 8461 
curl -sL https://mta-sts.co.uk/.well-known/mta-sts.txt
Check TLS-RPT record RFC 8460 
dig +short _smtp._tls.co.uk TXT

Brand & Trust

Check BIMI record BIMI Draft 
dig +short default._bimi.co.uk TXT
Check CAA records (certificate authority authorization) RFC 8659 
dig +noall +answer co.uk CAA

DNS Records

Check HTTPS/SVCB records RFC 9460 
dig +noall +answer co.uk HTTPS

Domain Security

Check CDS/CDNSKEY automation records RFC 7344 
dig +noall +answer co.uk CDS

Infrastructure Intelligence

RDAP domain registration lookup RFC 9083 
curl -sL 'https://rdap.org/domain/co.uk' | python3 -m json.tool | head -50
Search Certificate Transparency logs RFC 6962 
curl -s 'https://crt.sh/?q=%25.co.uk&output=json' | python3 -c "import json,sys; [print(e['name_value']) for e in json.load(sys.stdin)]" | sort -u | head -20
Check security.txt RFC 9116 
curl -sL https://co.uk/.well-known/security.txt | head -20

AI Surface

Check for llms.txt 
curl -sI https://co.uk/llms.txt | head -5
Check robots.txt for AI crawler rules 
curl -s https://co.uk/robots.txt | grep -i -E 'GPTBot|ChatGPT|Claude|Anthropic|Google-Extended|CCBot|PerplexityBot'
Commands use dig, openssl, and curl — standard tools available on macOS, Linux, and WSL. Results may vary slightly due to DNS propagation timing and resolver caching.
Intelligence Confidence Audit Engine Verified · 9/9 Evaluated
How confident are these results? Each protocol is independently verified against RFC standards. No self-awarded badges.
SPF
Verified 4908 runs
DKIM
Verified 4726 runs
DMARC
Verified 4891 runs
DANE/TLSA
Verified 4710 runs
DNSSEC
Verified 4889 runs
BIMI
Verified 4725 runs
MTA-STS
Verified 4728 runs
TLS-RPT
Verified 4730 runs
CAA
Verified 4722 runs
Maturity: Development → Verified → Consistent → Gold → Gold Master

Appendix: Verification Commands

The core DNS queries behind this report can be independently verified using these standard terminal commands (dig, openssl, curl). DNS Tool adds multi-resolver consensus, RFC-based evaluation, and cross-referencing on top of the raw data shown here.

DNS Records

Query A records (IPv4) (RFC 1035) 
dig +noall +answer co.uk A
Query AAAA records (IPv6) (RFC 1035) 
dig +noall +answer co.uk AAAA
Query MX records (mail servers) (RFC 1035) 
dig +noall +answer co.uk MX
Query NS records (nameservers) (RFC 1035) 
dig +noall +answer co.uk NS
Query TXT records (RFC 1035) 
dig +noall +answer co.uk TXT

Email Authentication

Check SPF record (RFC 7208) 
dig +short co.uk TXT | grep -i spf
Check DMARC policy (RFC 7489) 
dig +short _dmarc.co.uk TXT
Check DKIM key for selector 'default' (RFC 6376) 
dig +short default._domainkey.co.uk TXT
Check DKIM key for selector 'google' (RFC 6376) 
dig +short google._domainkey.co.uk TXT
Check DKIM key for selector 'selector1' (RFC 6376) 
dig +short selector1._domainkey.co.uk TXT
Check DKIM key for selector 'selector2' (RFC 6376) 
dig +short selector2._domainkey.co.uk TXT

Domain Security

Check DNSSEC DNSKEY records (RFC 4035) 
dig +dnssec +noall +answer co.uk DNSKEY
Check DNSSEC DS records (RFC 4035) 
dig +noall +answer co.uk DS
Validate DNSSEC chain (requires DNSSEC-validating resolver) (RFC 4035) 
dig +dnssec +cd co.uk A @1.1.1.1

Transport Security

Check TLSA record (replace MX_HOST with actual MX) (RFC 7672) 
dig +noall +answer _25._tcp.MX_HOST TLSA
Check MTA-STS DNS record (RFC 8461) 
dig +short _mta-sts.co.uk TXT
Fetch MTA-STS policy file (RFC 8461) 
curl -sL https://mta-sts.co.uk/.well-known/mta-sts.txt
Check TLS-RPT record (RFC 8460) 
dig +short _smtp._tls.co.uk TXT

Brand & Trust

Check BIMI record (BIMI Draft) 
dig +short default._bimi.co.uk TXT
Check CAA records (certificate authority authorization) (RFC 8659) 
dig +noall +answer co.uk CAA

DNS Records

Check HTTPS/SVCB records (RFC 9460) 
dig +noall +answer co.uk HTTPS

Domain Security

Check CDS/CDNSKEY automation records (RFC 7344) 
dig +noall +answer co.uk CDS

Infrastructure Intelligence

RDAP domain registration lookup (RFC 9083) 
curl -sL 'https://rdap.org/domain/co.uk' | python3 -m json.tool | head -50
Search Certificate Transparency logs (RFC 6962) 
curl -s 'https://crt.sh/?q=%25.co.uk&output=json' | python3 -c "import json,sys; [print(e['name_value']) for e in json.load(sys.stdin)]" | sort -u | head -20
Check security.txt (RFC 9116) 
curl -sL https://co.uk/.well-known/security.txt | head -20

AI Surface

Check for llms.txt 
curl -sI https://co.uk/llms.txt | head -5
Check robots.txt for AI crawler rules 
curl -s https://co.uk/robots.txt | grep -i -E 'GPTBot|ChatGPT|Claude|Anthropic|Google-Extended|CCBot|PerplexityBot'
Running Multi-Source Intelligence Audit

co.uk

0s
DNS records — Cloudflare, Google, Quad9, OpenDNS, DNS4EU
Email auth — SPF, DMARC, DKIM selectors
DNSSEC chain of trust & DANE/TLSA
Certificate Transparency & subdomain discovery
SMTP transport & STARTTLS verification
MTA-STS, TLS-RPT, BIMI, CAA
Registrar & infrastructure analysis
Intelligence Classification & Interpretation

Every result includes terminal commands you can run to independently verify the underlying data. No proprietary magic.