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https://semanticscholar.org

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
94
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.semanticscholar.org/
200https://semanticscholar.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://semanticscholar.org/ → https://semanticscholar.org/

Consistent

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

Certificate validity

289
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
4 A records, 38 ms lookup
PASS
4 A records, 38 ms lookup
Info::
Resolves to 4 IPv4 address(es)
Got: 13.227.173.66, 13.227.173.117, 13.227.173.108, 13.227.173.59
Info::
Has 8 IPv6 (AAAA) record(s)
Got: 2600:9000:21f7:4400:6:4565:580:93a1, 2600:9000:21f7:9000:6:4565:580:93a1, 2600:9000:21f7:600:6:4565:580:93a1, 2600:9000:21f7:e800:6:4565:580:93a1, 2600:9000:21f7:9c00:6:4565:580:93a1, 2600:9000:21f7:8000:6:4565:580:93a1, 2600:9000:21f7:3a00:6:4565:580:93a1, 2600:9000:21f7:3e00:6:4565:580:93a1
Info::
4 nameserver(s) configured
Got: ns-290.awsdns-36.com, ns-1772.awsdns-29.co.uk, ns-586.awsdns-09.net, ns-1437.awsdns-51.org
Info::
5 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: 38 ms
Got: 38 ms
A13.227.173.66, 13.227.173.117, 13.227.173.108, 13.227.173.59
AAAA2600:9000:21f7:4400:6:4565:580:93a1, 2600:9000:21f7:9000:6:4565:580:93a1, 2600:9000:21f7:600:6:4565:580:93a1, 2600:9000:21f7:e800:6:4565:580:93a1, 2600:9000:21f7:9c00:6:4565:580:93a1, 2600:9000:21f7:8000:6:4565:580:93a1, 2600:9000:21f7:3a00:6:4565:580:93a1, 2600:9000:21f7:3e00:6:4565:580:93a1
CNAME—
NSns-290.awsdns-36.com, ns-1772.awsdns-29.co.uk, ns-586.awsdns-09.net, ns-1437.awsdns-51.org
MX
1 aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com
10 aspmx3.googlemail.com
10 aspmx2.googlemail.com
TXT
SPF v=spf1 include:_spf.google.com a mx ip4:52.10.131.143 a mx ip4:52.11.211.149 ip4...
google-site-verification=XQD87lq7o-ceBjMa_bB7iZ-VbQAElBnOjnDXpRQOWf0
CAALookup not available with standard resolver
Resolved in 38 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), 446 ms total
PASS
1 redirect(s), 446 ms total
Info::
Single redirect
Got: https://semanticscholar.org → https://www.semanticscholar.org/ (301)
Info::
WWW normalization redirect

https://semanticscholar.org

197 ms · HTTP/1.1

301

https://www.semanticscholar.org/

249 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://semanticscholar.org301197 msHTTP/1.1nginx
2https://www.semanticscholar.org/200249 msHTTP/1.1nginx

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 2600:9000:21f7:4400:6:4565:580:93a1, 2600:9000:21f7:9000:6:4565:580:93a1, 2600:9000:21f7:600:6:4565:580:93a1, 2600:9000:21f7:e800:6:4565:580:93a1, 2600:9000:21f7:9c00:6:4565:580:93a1, 2600:9000:21f7:8000:6:4565:580:93a1, 2600:9000:21f7:3a00:6:4565:580:93a1, 2600:9000:21f7:3e00:6:4565:580:93a1
Got: 16 ms connect
IPv6 Ready
AAAA Records 2600:9000:21f7:4400:6:4565:580:93a1, 2600:9000:21f7:9000:6:4565:580:93a1, 2600:9000:21f7:600:6:4565:580:93a1, 2600:9000:21f7:e800:6:4565:580:93a1, 2600:9000:21f7:9c00:6:4565:580:93a1, 2600:9000:21f7:8000:6:4565:580:93a1, 2600:9000:21f7:3a00:6:4565:580:93a1, 2600:9000:21f7:3e00:6:4565:580:93a1 Connection Reachable (16 ms)
A+
Crawlability
robots.txt present, sitemap with 3331 URLs
PASS
robots.txt present, sitemap with 3331 URLs
Info::
robots.txt is present
Got: 574 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 3331 entries
Info::
Sitemap index with 3331 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 574 B Sitemaps referenced 3 User-agents * Blocking No — crawling allowed
# We are a non-profit research institute.  If you would like to collaborate with us,
# please contact us at: ai2-info@allenai.org
# Or check out our public API http://api.semanticscholar.org/
User-agent: *
Disallow: /search
Disallow: /error
Disallow: /me
Disallow: /api
Disallow: /author/*/claim
Disallow: /author/*?
Disallow: /paper/*?
Disallow: /reader/
Allow: /paper/*?p2df

Sitemap: https://www.semanticscholar.org/sitemap_author_index.xml
Sitemap: https://www.semanticscholar.org/sitemap_paper_index.xml
Sitemap: https://www.semanticscholar.org/sitemap_topic_index.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 3331 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
semanticscholar.org — via Amazon Registrar, Inc., 11 years, 9 months old
PASS
semanticscholar.org — via Amazon Registrar, Inc., 11 years, 9 months old
Info::
Domain registered until Sep 5, 2026 (4 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: Amazon Registrar, 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

55 days

September 5, 2026

SSL certificate

289 days

Issued by Amazon

Domain age

11 years, 9 months

Registered September 5, 2014

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Unknown

2600:9000:21f7:3e00:6:4565:580:93a1

Registrar

Amazon Registrar, Inc.

Unlocked 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Renew the domain or enable auto-renewal to prevent accidental expiry
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Amazon Registrar, Inc.
Created September 5, 2014 (11 years, 9 months ago)
Expires September 5, 2026 (4 months)
Last Updated September 3, 2025
Name Servers ns-1437.awsdns-51.org, ns-1772.awsdns-29.co.uk, ns-290.awsdns-36.com, ns-586.awsdns-09.net
DNSSEC Not enabled
Hosting
IP Address 2600:9000:21f7:3e00:6:4565:580:93a1
Data source: rdap (0.6s)

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

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 359 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
35 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.
19 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
359 ms
Total Time Total request time from DNS lookup through full response.
360 ms

Connection waterfall

DNS Lookup 35 ms TCP Connect 16 ms TLS Handshake 19 ms Server Processing 290 ms Content Transfer 0 ms
A
CDN & Delivery
AWS CloudFront (Miss from cloudfront)
PASS
AWS CloudFront (Miss from cloudfront)
Info::
Site is served via AWS CloudFront CDN (edge: CDG54-P2)
Got: x-amz-cf-id: oj29O6W_CiRsksywocmBJgwT-vsMlPlpfJj5DLJddRoKQWDyj4r7uA==
Info::
CDN cache status: Miss from cloudfront
CDN Detected: AWS CloudFront
Provider AWS CloudFront Cache Status Miss from cloudfront Evidence x-amz-cf-id: oj29O6W_CiRsksywocmBJgwT-vsMlPlpfJj5DLJddRoKQWDyj4r7uA==
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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