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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
95
GRADE
A
FIX
0
REVIEW
2
PASS
7
INFO
0
Probed from Singapore, Singapore
200 OK
Checks
9
7 PASS 2 REVIEW
B
DNS Records
1 A records, 85 ms lookup
REVIEW
1 A records, 85 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 151.101.78.133
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
Has 1 IPv6 (AAAA) record(s)
Got: 2a04:4e42:12::645
Warning::
CNAME record at zone apex
A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.
Got: dualstack.d.sni.global.fastly.net
Info::
No NS records found
Info::
No MX records — email not configured via DNS
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Info::
DNS resolution time: 85 ms
Got: 85 ms
A151.101.78.133
AAAA2a04:4e42:12::645
CNAMEdualstack.d.sni.global.fastly.net
NS—
MX—
TXT—
CAALookup not available with standard resolver
Resolved in 85 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more ▾

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.

Why this matters

CNAME at the apex (example.com) breaks every other apex record (MX, TXT, NS) — DNS-protocol violation per RFC 1034.

Learn more ▾

RFC 1034 forbids CNAME alongside other records at the same name. Some DNS providers offer ALIAS / ANAME / flattened-CNAME records that work around this — use those instead. Otherwise apex-level CNAME breaks email (no MX), domain ownership verification (no TXT), and more.

Source: RFC 1034

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.

Why this matters

Without SPF, receiving servers can't validate sending IPs — your domain is easier to spoof in phishing.

Learn more ▾

SPF complements DMARC. Both should be published. SPF records list authorized sending IPs (e.g., `v=spf1 include:_spf.google.com ~all` for Google Workspace). After publishing, verify in Google Postmaster Tools or mxtoolbox.

Source: RFC 7208 (SPF)

B
TLS Certificate Expiry & Recommendations
178 days until leaf cert expires — 5 issues to address
REVIEW

Certificate validity

178
days left
0d 30d 60d 90d+

Recommended actions

  • Prefer TLS 1.3 — TLS 1.2 is acceptable but TLS 1.3 removes RSA key exchange and improves latency
  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • Enable DNSSEC on your domain for DNS spoofing protection
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://www.ted.com

https://www.ted.com

201 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.ted.com200201 msHTTP/1.1nginx/1.27.5
A+
IPv6 Readiness
IPv6 reachable (75 ms)
PASS
IPv6 reachable (75 ms)
Info::
IPv6 is configured and reachable at 2a04:4e42:12::645
Got: 75 ms connect
IPv6 Ready
AAAA Records 2a04:4e42:12::645 Connection Reachable (75 ms)
A+
Crawlability
robots.txt present, sitemap with 28 URLs
PASS
robots.txt present, sitemap with 28 URLs
Info::
robots.txt is present
Got: 1040 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 28 entries
Info::
Sitemap index with 28 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 1040 B Sitemaps referenced 1 User-agents Applebot-Extended, Bytespider, FriendlyCrawler, GPTBot, meta-externalagent, OAI-SearchBot, omgili, PerplexityBot, *, Baiduspider, Amazonbot, anthropic-ai, CCBot, cohere-ai, Meta-ExternalAgent, FacebookBot, ImagesiftBot, Diffbot, ChatGPT-User, ClaudeBot, omgilibot Blocking No — crawling allowed
User-agent: *
Disallow: /search
Disallow: /latest
Disallow: /latest-talk
Disallow: /latest-playlist
Disallow: /people
Disallow: /profiles
Disallow: /themes/rss

User-agent: Baiduspider
Disallow: /search
Disallow: /latest
Disallow: /latest-talk
Disallow: /latest-playlist
Disallow: /people
Disallow: /profiles

User-agent: Amazonbot
Disallow: /

User-agent: anthropic-ai
Disallow: /

User-agent: Applebot-Extended
Disallow: /

User-agent: Bytespider
Disallow: /

User-agent: CCBot
Disallow: /

User-agent: ChatGPT-User
Disallow: /

User-agent: ClaudeBot
Disallow: /

User-agent: cohere-ai
Disallow: /

User-agent: Diffbot
Disallow: /

User-agent: FacebookBot
Disallow: /

User-agent: FriendlyCrawler
Disallow: /

User-agent: GPTBot
Disallow: /

User-agent: ImagesiftBot
Disallow: /

User-agent: meta-externalagent
User-agent: Meta-ExternalAgent
Disallow: /

User-Agent: OAI-SearchBot
Allow: /

User-agent: omgili
Disallow: /

User-agent: omgilibot
Disallow: /

User-Agent: PerplexityBot
Disallow: /

Sitemap: https://www.ted.com/sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 28 entries Valid XML Yes
Child Sitemaps:
A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
www/non-www redirect configured correctly (preferred: www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.ted.com/
301https://ted.com/

Preferred variant: www

HTTP → HTTPS

301http://www.ted.com/ → https://www.ted.com/

Consistent

A+
Domain Intelligence
ted.com — via Name.com, Inc., 31 years, 10 months old, hosted on AWS
PASS
ted.com — via Name.com, Inc., 31 years, 10 months old, hosted on AWS
Info::
Domain registered until Nov 7, 2026 (7 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: Name.com, Inc.
Info::
Hosting: AWS
Got: AS14618
Domain expiry

146 days

November 7, 2026

SSL certificate

178 days

Issued by Sectigo Limited

Domain age

31 years, 10 months

Registered November 8, 1994

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS14618

34.224.34.177

Registrar

Name.com, Inc.

Lock status unknown 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
Registrar Name.com, Inc.
Created November 8, 1994 (31 years, 10 months ago)
Expires November 7, 2026 (7 months)
Last Updated October 8, 2025
Name Servers ns-1133.awsdns-13.org, ns-191.awsdns-23.com, ns-1975.awsdns-54.co.uk, ns-882.awsdns-46.net
DNSSEC Not enabled
Hosting
IP Address 34.224.34.177
ASN AS14618 (AMAZON-AES - Amazon.com, Inc., US)
Provider AWS
Data source: rdap (6.5s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.

Learn more ▾

DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.

Source: ICANN / RFC 4033

A
HTTP Probe Timing
Total 510 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
249 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
41 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
86 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
420 ms
Total Time Total request time from DNS lookup through full response.
511 ms

Connection waterfall

DNS Lookup 249 ms TCP Connect 41 ms TLS Handshake 86 ms Server Processing 44 ms Content Transfer 90 ms
A+
CDN & Delivery
Fastly (HIT)
PASS
Fastly (HIT)
Info::
Site is served via Fastly CDN
Got: x-served-by: cache-sin-wsat1880028-SIN
Info::
CDN cache status: HIT
CDN Detected: Fastly
Provider Fastly Cache Status HIT Evidence x-served-by: cache-sin-wsat1880028-SIN
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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