Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Probed from Singapore, Singapore

301 Moved Permanently

Checks

4 PASS 3 REVIEW 2 FIX

URL Variants

Action

www/non-www, trailing slash, HTTP→HTTPS

FIX

www/non-www, trailing slash, HTTP→HTTPS

Both www and non-www versions serve content

Got: Both variants return 200 Expected: One variant 301-redirects to the other

HTTP version does not redirect to HTTPS

Got: HTTP 301 Expected: 301 redirect to HTTPS

www / non-www

200https://www.pbs.org/

200https://pbs.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://pbs.org/ → http://www.pbs.org/

HTTP version does not redirect to HTTPS

CDN & Delivery

Action

No CDN detected

FIX

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.

Redirect Chain

1 redirect(s), 1563 ms total

REVIEW

1 redirect(s), 1563 ms total

Single redirect

Got: https://pbs.org → https://www.pbs.org/ (301)

WWW normalization redirect

Redirect overhead: 1563 ms total

Got: 1563 ms

https://pbs.org

748 ms · HTTP/1.1

301

https://www.pbs.org/

814 ms · HTTP/1.1 FINAL

#	URL	Status	Time	Protocol	Server
1	https://pbs.org	301	748 ms	HTTP/1.1	openresty
2	https://www.pbs.org/	200	814 ms	HTTP/1.1	CloudFront

See the visual redirect chain in the HTTP Probe tab →

IPv6 Readiness

Action

No IPv6 support

REVIEW

No IPv6 support

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

TLS Certificate Expiry & Recommendations

70 days until leaf cert expires — 3 issues to address

REVIEW

Certificate validity

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, 16 ms lookup

PASS

2 A records, 16 ms lookup

Resolves to 2 IPv4 address(es)

Got: 54.225.206.152, 54.225.198.196

No IPv6 (AAAA) records

4 nameserver(s) configured

Got: ns-1230.awsdns-25.org, ns-1674.awsdns-17.co.uk, ns-193.awsdns-24.com, ns-806.awsdns-36.net

1 mail exchanger(s) configured

CAA records not checked

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

SPF record present in TXT

DNS resolution time: 16 ms

Got: 16 ms

A	54.225.206.152, 54.225.198.196
AAAA	—
CNAME	—
NS	ns-1230.awsdns-25.org, ns-1674.awsdns-17.co.uk, ns-193.awsdns-24.com, ns-806.awsdns-36.net
MX	10 pbs-org.mail.protection.outlook.com
TXT	Jr4+zjA9dTLAFxFkcph9AFpTVWwXq7oMKDgVMkankOriEatYCDuzU/WQK2Gyuees8j7z+OBI98TsF/2x... MS=ms14905487 MS=ms58428140 ZOOM_verify_mEujaWwm5dMExViFaHNZl9 anthropic-domain-verification-3bj3y3=FaFrOgE4p15xv9e00c1EN3u1w atlassian-domain-verification=xXbRj/JToaVlStqe/9rvbIVJTPvROKeb7MXvPsaCwdD2tFWAkq... atlassian-domain-verification=xsGmA8QYmOMhZ9YdIm9bQMseNYOXvOKmciPOg2aD23hRgnwYXp... atlassian-sending-domain-verification=2c13394a-b258-4d38-a457-eab648b5e0aa brevo-code:ba178c29138917649adaeb118f884b18 cisco-ci-domain-verification=25f97f6c108aa08314f1a41d1202369fb654e43cf29250ed772... d365mktkey=5jhrhdpz5qtqb8ppw9nm95rnw detectify-verification=1583bf00b85b6570195c4ec81a2625ae docusign=12c0f1de-fcbf-4461-bcc9-57cfcbee1e1a facebook-domain-verification=hxcquifih7vsf9z0u39e2t2ks317j6 google-site-verification=1q7KpRbb72jFQk6X7jgmKIrfzb1DZBeRtaXtkuNua-Y google-site-verification=38943G797swQqVx4L2quzrbny_CcmFOjx0qzJPAwhTY google-site-verification=5gDTeKSkUctitTQInZRfAr78uxoKDfDJCysJrCkPfeo google-site-verification=8yJvWAgyzPHlrdB5CGCDjTq0raQf861mwEGE25P_FLQ google-site-verification=T2_cy5E9wKg4wpYbEb4t5m-SX0Uxz00XrgwueP1jOhU google-site-verification=cB2-sH4zbNRhFrpCGjSWpojYsgGosef904g_gI5VLnI google-site-verification=oB2RzGB5K77Yaia4d4yRU9YzfxQGpGwUE-mS6Npl9OI google-site-verification=oiiWhKuvkmnM080OtUGP2jT-CexdhCkATjyELBh7Odk have-i-been-pwned-verification=dweb_jzhg1z2wr7iv7l7mue5f6t0k iContact1760978 openai-domain-verification=dv-My8fClm9MqKjWAexRtqOWtV1 pardot963303=eb019aebebc852309d6358ac3aec298343b66ab28978dc28037464aced4c60d1 pdq-domain-verification=NP4n68pln458 postman-domain-verification=53d20208c464282ca428dcbd1fbb5b5dde64c4403e704b3e0b41... status-page-domain-verification=g90gln3s127q tollbit-domain-verification=cf1bd6a46c1d6b8fb731af6e314086e4d5af03dbcfa9f1b35806... SPF v=spf1 include:_u.pbs.org._spf.smart.ondmarc.com ~all
CAA	Lookup not available with standard resolver

Resolved in 16 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+

Crawlability

robots.txt present, sitemap with 6246 URLs

PASS

robots.txt present, sitemap with 6246 URLs

robots.txt is present

Got: 3451 bytes

sitemap.xml is present

sitemap.xml is valid XML

sitemap.xml contains 6246 entries

Sitemap index with 6246 child sitemaps

robots.txt references sitemap

robots.txt 200 OK

Size 3451 B Sitemaps referenced 4 User-agents Baiduspider, GPTBot, CCBot, PerplexityBot, * Blocking No — crawling allowed

User-agent: *
Crawl-delay: 1
Disallow: /wgbh/pages/frontline/digitalnation/%3F
Disallow: /wgbh/pages/frontline/digitalnation/%3F*
Disallow: /wgbh/frontline/*elqat*
Disallow: /wgbh/pages/frontline/*elqat*
Disallow: /wgbh/pages/frontline/bushswar*
Disallow: /independentlens/getinvolved/cinema/
Disallow: /cgi-bin/*
Disallow: /cgi-registry/*
Disallow: /survey/
Disallow: /whatson/stations/
Disallow: /whatson/schedulex/
Disallow: /whatson/pbsyou/
Disallow: /whatson/dbs/
Disallow: /remotecontrol/bestpractices/prototype/
Disallow: /remotecontrol/bestpractices/jl-prototype/
Disallow: /pressroom/
Disallow: /als/shakespeare_pilot/
#Disallow: /.
Disallow: /newshour/bb/military/military.html/
Disallow: /producers/webmanual/
Disallow: /devcon2007/
Disallow: /smcot/
Disallow: /pbsholidaycard/
Disallow: /gpra/
Disallow: /tlqa/
Disallow: /remote.control/
Disallow: /teachers/connect/
Disallow: /engage/sites/all/files/blog_images/monkeys.gif
Disallow: /teachers/edcar/
Disallow: /teachers/dll_research/
Disallow: /peerconnection/feeds/
Disallow: /teachers/innovators/toolkit/
Disallow: /mt4/
Disallow: /klru/mt4/
Disallow: /newshour/mt4/
Disallow: /mediashift/mt4/
Disallow: /kcet/mt4/
Disallow: /newshour/mt3/
Disallow: /now/mt3/
Disallow: /itvs/mt3/
Disallow: /pbs/mt3/
Disallow: /pbs/mt3o4/
Disallow: /pbs/mt4/
Disallow: /pbs/teachers/mt3/
Disallow: /pbs/kids/mt3/
Disallow: /pbs/kids/mt4/
Disallow: /pbs/src/mt4/
Disallow: /pbs/parents/mt4/
Disallow: /pbsi/mt3/
Disallow: /moyers/mt3/
Disallow: /moyers/mt4/
Disallow: /nbr/mt3/
Disallow: /nbr/mt4/
Disallow: /cringely/mt3/
Disallow: /cringely/mt4/
Disallow: /wgbh/mt4/
Disallow: /wnet/expose/mt4/
Disallow: /wnet/mt4/
Disallow: /opb/mt4/
Disallow: /search/search_results.html?q=*
Disallow: /wgbh/nova/search/
Disallow: /wgbh/nova/search/results/*
Disallow: /wgbh/nova/beta/search/results/*
Disallow: /nbr/info/search.html?*
Disallow: /independentlens/video/index.php?*
Disallow: /independentlens/video/?filter=*
Disallow: /wnet/religionandethics/*/index.html?*
Disallow: /wnet/religionandethics/search_results.html*
Disallow: /teachers/search/resources/?q=* 
Disallow: /teacherline/catalog/browse/ 
Disallow: /thewar/search_results.php?* 
Disallow: */emailthispage.html?* 
Disallow: /pov_mt/mt4/ 
Disallow: /newshour/indepth_coverage/middle_east/iraq/honorroll/search.php?*
Disallow: /includes/ 
Disallow: */emailthispage.html 
Disallow: /about/faq/station-finder/?state-text=* 
Disallow: /about/faq/station-finder/?zip-text=* 
Disallow: /wgbh/nova/search-results.html 
Disallow: /wgbh/americanexperience/about/search/search_results.html 
Disallow: /moyers/journal/about/search_google.html
Disallow: /foundation/contact/
Disallow: *?replytocom
Disallow: /social_media/
Disallow: /independentlens/film-lists/watch-online/
Disallow: /show/koth-show/
Disallow: /my-list-videos/
Disallow: /my-list-shows/
Disallow: /my-list-viewing-history/
Disallow: /parents/activity-finder/
Disallow: /parents/search/
Sitemap: https://www.pbs.org/sitemap.xml
Sitemap: http://www.pbs.org/mercy-street/sitemap.xml
Sitemap: https://www.pbs.org/newshour/sitemaps/sitemap.xml
Sitemap: https://www.pbs.org/weta/washingtonweek/sitemap.xml

User-Agent: Baiduspider 
Disallow: /independentlens/getinvolved/cinema/
Disallow: /independentlens/films/watch-online/*

User-agent: GPTBot
Disallow: /

User-agent: CCBot
Disallow: /

User-agent: PerplexityBot
Disallow: /

User-agent: *
Disallow: /ga-actions/formie/forms/refresh-tokens

sitemap.xml 200 OK

Type Sitemap Index URLs 6246 entries Valid XML Yes

Child Sitemaps:

A+

Domain Intelligence

pbs.org — via CSC Corporate Domains, Inc., 31 years, 5 months old, hosted on AWS

PASS

pbs.org — via CSC Corporate Domains, Inc., 31 years, 5 months old, hosted on AWS

Domain registered until Apr 20, 2027 (1 years remaining)

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.

Registrar: CSC Corporate Domains, Inc.

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.

Hosting: AWS

Got: AS14618

Domain expiry

280 days

April 20, 2027

SSL certificate

70 days

Issued by Let's Encrypt

Domain age

31 years, 5 months

Registered April 19, 1995

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS14618

54.225.198.196

Registrar

CSC Corporate Domains, Inc.

Unlocked 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
Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers

Registrar CSC Corporate Domains, Inc.

Created April 19, 1995 (31 years, 5 months ago)

Expires April 20, 2027 (1 years)

Last Updated April 21, 2026

Name Servers ns-1230.awsdns-25.org, ns-1674.awsdns-17.co.uk, ns-193.awsdns-24.com, ns-806.awsdns-36.net

DNSSEC Not enabled

Hosting

IP Address 54.225.198.196

ASN AS14618 (AMAZON-AES - Amazon.com, Inc., US)

Provider AWS

Data source: rdap (1.2s)

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

HTTP Probe Timing

Total 783 ms — DNS, TCP, TLS, TTFB, content transfer breakdown

PASS

DNS Lookup

4 ms

TCP Connect

259 ms

TLS Handshake

262 ms

Time to First Byte

784 ms

Total Time

784 ms

Connection waterfall

DNS Lookup 4 ms TCP Connect 259 ms TLS Handshake 262 ms Server Processing 258 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.