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https://doi.org

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
93
GRADE
A
FIX
0
REVIEW
2
PASS
7
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
7 PASS 2 REVIEW
B
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
www/non-www, trailing slash, HTTP→HTTPS
Critical::
Both www and non-www versions serve content
Got: Both variants return 200 Expected: One variant 301-redirects to the other
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.doi.org/
200https://doi.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://doi.org/ https://doi.org/

Consistent

B
TLS Certificate Expiry & Recommendations
63 days until leaf cert expires — 2 issues to address
REVIEW

Certificate validity

63
days left
0d 30d 60d 90d+

Recommended actions

  • Submit your domain to hstspreload.org to be added to the Chrome preload list
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
DNS Records
3 A records, 32 ms lookup
PASS
3 A records, 32 ms lookup
Info::
Resolves to 3 IPv4 address(es)
Got: 104.26.5.132, 104.26.4.132, 172.67.69.3
Info::
Has 3 IPv6 (AAAA) record(s)
Got: 2606:4700:20::ac43:4503, 2606:4700:20::681a:584, 2606:4700:20::681a:484
Info::
2 nameserver(s) configured
Got: josh.ns.cloudflare.com, zita.ns.cloudflare.com
Info::
3 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 32 ms
Got: 32 ms
A104.26.5.132, 104.26.4.132, 172.67.69.3
AAAA2606:4700:20::ac43:4503, 2606:4700:20::681a:584, 2606:4700:20::681a:484
CNAME
NSjosh.ns.cloudflare.com, zita.ns.cloudflare.com
MX
10 mx.zoho.eu
20 mx2.zoho.eu
50 mx3.zoho.eu
TXT
SPF v=spf1 include:zohomail.eu include:cnri.net include:amazonses.com ~all
zoho-verification=zb37490279.zmverify.zoho.eu
CAALookup not available with standard resolver
Resolved in 32 ms

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.

A
Redirect Chain
1 redirect(s), 159 ms total
PASS
1 redirect(s), 159 ms total
Info::
Single redirect
Got: https://doi.org → https://www.doi.org/ (301)
Info::
WWW normalization redirect

https://doi.org

62 ms · HTTP/1.1

301

https://www.doi.org/

97 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://doi.org30162 msHTTP/1.1cloudflare
2https://www.doi.org/20097 msHTTP/1.1AmazonS3

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (16 ms)
PASS
IPv6 reachable (16 ms)
Info::
IPv6 is configured and reachable at 2606:4700:20::ac43:4503, 2606:4700:20::681a:584, 2606:4700:20::681a:484
Got: 16 ms connect
IPv6 Ready
AAAA Records 2606:4700:20::ac43:4503, 2606:4700:20::681a:584, 2606:4700:20::681a:484 Connection Reachable (16 ms)
A+
Crawlability
robots.txt present, sitemap with 41 URLs
PASS
robots.txt present, sitemap with 41 URLs
Info::
robots.txt is present
Got: 39 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 41 entries
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 39 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent: *

Allow: /

Disallow: /_


A+
Domain Intelligence
doi.org — via Cloudflare, Inc., 27 years, 7 months old
PASS
doi.org — via Cloudflare, Inc., 27 years, 7 months old
Info::
Domain registered until Jan 19, 2035 (8 years, 10 months remaining)
Info::
DNSSEC is enabled
Info::
Registrar: Cloudflare, Inc.
Warning::
Registrar lock is NOT enabled
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Domain expiry

3077 days

January 19, 2035

SSL certificate

63 days

Issued by Google Trust Services

Domain age

27 years, 7 months

Registered January 19, 1999

DNSSEC

Enabled

Protects against DNS spoofing

Hosting

Unknown

2606:4700:20::ac43:4503

Registrar

Cloudflare, Inc.

Unlocked 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Cloudflare, Inc.
Created January 19, 1999 (27 years, 7 months ago)
Expires January 19, 2035 (8 years, 10 months)
Last Updated July 12, 2025
Name Servers josh.ns.cloudflare.com, zita.ns.cloudflare.com
DNSSEC Enabled
Hosting
IP Address 2606:4700:20::ac43:4503
Data source: rdap (0.6s)

The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.

Why this matters

Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.

Learn more

Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A+
HTTP Probe Timing
Total 91 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
32 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
16 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
22 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
92 ms
Total Time Total request time from DNS lookup through full response.
92 ms

Connection waterfall

DNS Lookup 32 ms TCP Connect 16 ms TLS Handshake 22 ms Server Processing 22 ms Content Transfer 0 ms
A+
CDN & Delivery
Cloudflare (HIT)
PASS
Cloudflare (HIT)
Info::
Site is served via Cloudflare CDN (edge: CDG)
Got: cf-ray: 9ed4d34a4d65f0f8-CDG
Info::
CDN cache status: HIT
CDN Detected: Cloudflare
Provider Cloudflare Cache Status HIT Evidence cf-ray: 9ed4d34a4d65f0f8-CDG
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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