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https://ndl.go.jp

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
79
GRADE
C
FIX
1
REVIEW
4
PASS
3
INFO
1
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
3 PASS 4 REVIEW 1 FIX
D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

B
Redirect Chain
1 redirect(s), 1889 ms total
REVIEW
1 redirect(s), 1889 ms total
Info::
Single redirect
Got: https://ndl.go.jp → https://www.ndl.go.jp:443/ (301)
Info::
WWW normalization redirect
Warning::
Redirect overhead: 1889 ms total
Got: 1889 ms

https://ndl.go.jp

657 ms · HTTP/1.1

301

https://www.ndl.go.jp:443/

1232 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://ndl.go.jp301657 msHTTP/1.1awselb/2.0
2https://www.ndl.go.jp:443/2001232 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

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.ndl.go.jp/
200https://ndl.go.jp/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://ndl.go.jp/ → https://www.ndl.go.jp:443/

Consistent

B
TLS Certificate Expiry & Recommendations
263 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

263
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • 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
DNS Records
2 A records, 278 ms lookup
PASS
2 A records, 278 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 166.117.141.228, 75.2.78.160
Info::
No IPv6 (AAAA) records
Info::
5 nameserver(s) configured
Got: dns-a.iij.ad.jp, ns2.ndl.go.jp, ns3.ndl.go.jp, ns.ndl.go.jp, ns4.ndl.go.jp
Info::
2 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
Warning::
DNS resolution is slow (278 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 278 ms
A166.117.141.228, 75.2.78.160
AAAA—
CNAME—
NSdns-a.iij.ad.jp, ns2.ndl.go.jp, ns3.ndl.go.jp, ns.ndl.go.jp, ns4.ndl.go.jp
MX
10 tn-vmw-mgw0001.ndl.go.jp
30 tn-vmw-mgw0002.ndl.go.jp
TXT
SPF v=spf1 +mx +ip4:153.231.248.161 +ip4:153.231.248.162 +ip4:153.231.248.169 +ip4:1...
CAALookup not available with standard resolver
Resolved in 278 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.

Slow DNS adds latency to every page load. Consider a faster DNS provider.

Why this matters

DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.

Source: DNS performance benchmarks

A+
Crawlability
robots.txt present, sitemap with 1 URLs
PASS
robots.txt present, sitemap with 1 URLs
Info::
robots.txt is present
Got: 66 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 1 entries
Info::
Sitemap index with 1 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 66 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
User-agent: *
Allow: /

Sitemap: https://www.ndl.go.jp/sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 1 entries Valid XML Yes
Child Sitemaps:
A
HTTP Probe Timing
Total 709 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
45 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
1 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
443 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
709 ms
Total Time Total request time from DNS lookup through full response.
709 ms

Connection waterfall

DNS Lookup 45 ms TCP Connect 1 ms TLS Handshake 443 ms Server Processing 221 ms Content Transfer 0 ms
Domain Intelligence
Domain intelligence data not available
INFO
Domain intelligence data not available

RDAP and WHOIS lookup both failed

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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