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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
89
GRADE
B
FIX
1
REVIEW
2
PASS
6
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
6 PASS 2 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.

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

Certificate validity

355
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
1 A records, 656 ms lookup
PASS
1 A records, 656 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 128.220.193.2
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: ens1.jhu.edu, ens1.jhmi.edu
Info::
1 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 (656 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 656 ms
A128.220.193.2
AAAA—
CNAME—
NSens1.jhu.edu, ens1.jhmi.edu
MX
1 smtp.johnshopkins.edu
TXT
apple-domain-verification=puEi9pYMYXEBi6bg
cisco-ci-domain-verification=4076af602b47f3714aa27fbdc0e14da0ca421ee8838942eabd7...
e2ma-verification=e15fb
ERF+yrd/ZMTjPnD5bs/nBFo+y0qQgnrv6og7UQaJONReXkEFyLl3peWV1tnVep8tHaJ1RgDgxvRplFYI...
google-site-verification=hNzuzBrLneJ7I5LUSy4YheAPZH2ZTk4Lhz76BOMrViE
ZOOM_verify_HBPKAym7Tz-eFLcbrv5qMQ
google-site-verification=5Zsy53rEK-hXGheCVnv_KOA9ga3WMOe8LQlInYaE668
asv=5da62ba592bab3d1542dbbf409a762ee
facebook-domain-verification=w4q5d6dqct374zdq9lk2a8yfsucsne
atlassian-domain-verification=v82iuU5jtUo6DLhV8wuZZxOk5KYBZdPh/5H+/GFe2/qw/ulV5g...
include:50639708.spf04.hubspotemail.netv=spf1 ip4:128.220.39.0/24 ip4:162.129.19...
be53a892b3bf7129c12261ba89e8317ddc94023220d76fd9fa150b6d4b8f5c24
6d0krd2r1m6d4rfp4y16ryvjq72x1wj4
ca3-54ded686d84a42a6a8e74e31814ecad8
docusign=47d09d1e-f20e-45ae-8348-9e0cde59d212
google-site-verification=Hdg6lOHShC5P7Lb-ffkmurUN4E5BFTJ3NLZJu_9veDk
apple-domain-verification=42Nv9AYu4nSWv2l4
addevent=verification
google-site-verification=OYMuhxFsKdAKd7rlfSh6j9u2RU7ZlLOIMb-apkt_TLE
facebook-domain-verification=og2369fpji19hzsapehl97bxys6cna
docusign=e0788c6f-1ca1-40be-b4f8-7e1516c85ef1
wkq43htjtz52dntbmtjw17pv0tqbbv0m
facebook-domain-verification=llmgbgm34s61kngl4fu1njobuwv9dc
airtable-verification=79c988870bd1359906d21b0f994f3e00
smartsheet-site-validation=o1IiE_3MJXBZ0xFwfwhtOhRmrOKxm1A8
google-site-verification=PogZzKp2fPlmh5CJooxo4w6DOBZvtzxL0aBOsSiGZwI
xr53hrygrc5x351yc9rts2ggkv08kb3k
STKWsca/U+sp2fESD+L8E88fJJ/CVjPAf5Td1GTp3H+Qp45vNgVnofYNV9mj4wsk8YaFZSVLsFxNzJNg...
google-site-verification=ilMpBs6aLedW4vFTLGnCyGYoQuSB5azucOxwxSMIsbg
AppId=000000004C0DFC04
google-site-verification=_78PEuF0BsnxniCMxdFGUXI8-rKuzXbA8w65yi5lRIs
docusign=73173acb-df50-4cbd-b139-cc9adedeae7d
google-site-verification=czjH79sUqAY6z7WdhXo0K3Z_uB8PQrWPoYZFLyG2ZyI
SPF v=spf1 ip4:128.220.39.0/24 ip4:162.129.199.0/24 ip4:128.220.229.235 ip4:162.129....
facebook-domain-verification=fui05pg5padt3lqjitadnizlq80543
anthropic-domain-verification-swf0eb=RQ8Zfyg8S3PQ2BZYxq1laA9K6
docusign=29c2d014-367b-4c7c-a9fe-d6512a2f37b1
CAALookup not available with standard resolver
Resolved in 656 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

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
Redirect Chain
1 redirect(s), 602 ms total
PASS
1 redirect(s), 602 ms total
Info::
Single redirect
Got: https://jhu.edu → https://www.jhu.edu/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 602 ms total
Got: 602 ms

https://jhu.edu

421 ms · HTTP/1.1

301

https://www.jhu.edu/

181 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://jhu.edu301421 msHTTP/1.1nginx/1.29.3
2https://www.jhu.edu/403181 msHTTP/1.1cloudflare

See the visual redirect chain in the HTTP Probe tab →

A+
Crawlability
robots.txt present, sitemap with 2 URLs
PASS
robots.txt present, sitemap with 2 URLs
Info::
robots.txt is present
Got: 1924 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 2 entries
Info::
Sitemap index with 2 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 1924 B Sitemaps referenced 1 User-agents Google-Extended, meta-externalagent, semrush, glutenfree, *, Applebot-Extended, Bytespider, CCBot, ClaudeBot, CloudflareBrowserRenderingCrawler, GPTBot, Amazonbot Blocking No — crawling allowed
# As a condition of accessing this website, you agree to abide by the following
# content signals:

# (a)  If a Content-Signal = yes, you may collect content for the corresponding
#      use.
# (b)  If a Content-Signal = no, you may not collect content for the
#      corresponding use.
# (c)  If the website operator does not include a Content-Signal for a
#      corresponding use, the website operator neither grants nor restricts
#      permission via Content-Signal with respect to the corresponding use.

# The content signals and their meanings are:

# search:   building a search index and providing search results (e.g., returning
#           hyperlinks and short excerpts from your website's contents). Search does not
#           include providing AI-generated search summaries.
# ai-input: inputting content into one or more AI models (e.g., retrieval
#           augmented generation, grounding, or other real-time taking of content for
#           generative AI search answers).
# ai-train: training or fine-tuning AI models.

# ANY RESTRICTIONS EXPRESSED VIA CONTENT SIGNALS ARE EXPRESS RESERVATIONS OF
# RIGHTS UNDER ARTICLE 4 OF THE EUROPEAN UNION DIRECTIVE 2019/790 ON COPYRIGHT
# AND RELATED RIGHTS IN THE DIGITAL SINGLE MARKET.

# BEGIN Cloudflare Managed content

User-agent: *
Content-Signal: search=yes,ai-train=no
Allow: /

User-agent: Amazonbot
Disallow: /

User-agent: Applebot-Extended
Disallow: /

User-agent: Bytespider
Disallow: /

User-agent: CCBot
Disallow: /

User-agent: ClaudeBot
Disallow: /

User-agent: CloudflareBrowserRenderingCrawler
Disallow: /

User-agent: Google-Extended
Disallow: /

User-agent: GPTBot
Disallow: /

User-agent: meta-externalagent
Disallow: /

# END Cloudflare Managed Content

User-agent: semrush
User-agent: glutenfree
Disallow: /

User-agent: *
Disallow: /wp-admin/
Allow: /wp-admin/admin-ajax.php

Sitemap: https://www.jhu.edu/wp-sitemap.xml
Disallow: /search/
sitemap.xml 200 OK
Type Sitemap Index URLs 2 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::
HTTP correctly 301-redirects to HTTPS

www / non-www

403https://www.jhu.edu/
200https://jhu.edu/

HTTP → HTTPS

301http://jhu.edu/ → https://www.jhu.edu/

Consistent

A+
Domain Intelligence
jhu.edu — 39 years, 7 months old, hosted on JHU - Johns Hopkins University, US
PASS
jhu.edu — 39 years, 7 months old, hosted on JHU - Johns Hopkins University, US
Info::
Domain registered until Jul 31, 2027 (1 years, 3 months remaining)
Info::
Hosting: JHU - Johns Hopkins University, US
Got: AS5723
Domain expiry

381 days

July 31, 2027

SSL certificate

355 days

Issued by Internet2

Domain age

39 years, 7 months

Registered March 19, 1987

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

JHU - Johns Hopkins University, US

ASN AS5723

128.220.193.2

Registrar

Registrar unknown

Lock status unknown 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Registrar
Created March 19, 1987 (39 years, 7 months ago)
Expires July 31, 2027 (1 years, 3 months)
Last Updated February 25, 2026
Name Servers ens1.jhmi.edu, ens1.jhu.edu
Registrant Johns Hopkins University
Hosting
IP Address 128.220.193.2
ASN AS5723 (JHU - Johns Hopkins University, US)
Provider JHU - Johns Hopkins University, US
Data source: whois (1.0s)
A
HTTP Probe Timing
Total 646 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
194 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
106 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
244 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
646 ms
Total Time Total request time from DNS lookup through full response.
646 ms

Connection waterfall

DNS Lookup 194 ms TCP Connect 106 ms TLS Handshake 244 ms Server Processing 102 ms Content Transfer 0 ms
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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