o2.sk

Readiness by lane

Green: o2.sk. Thin bar: Telecommunications & Internet peer median.

Priority fixes for o2.sk

Ordered by impact and by how common each practice is among peers.

1. Priority 1 · Enable

   Mobile viewport configured

   Observed: The homepage had no viewport meta tag, so phones may render it zoomed out.

   Why it matters: Without it, phones render the page at desktop width and shrink it, which makes text tiny and hard to use.

   What to do: Add <meta name="viewport" content="width=device-width, initial-scale=1"> and check the layout on small screens.

   98% of Telecommunications & Internet peers do this. Limit: Based on the homepage HTML delivered to an automated client; scripts that run later were not executed.

   Guide: Responsive Web Design Checklist for Real Devices

2. Priority 2 · Harden

   HSTS kept for at least a year

   Observed: The homepage response did not include a Strict-Transport-Security header.

   What to do: Send Strict-Transport-Security on HTTPS responses. Start with a short max-age (for example 300 seconds), confirm every subdomain works over HTTPS, then raise it in steps to 31536000. Add includeSubDomains only when all subdomains are HTTPS. HSTS preload is optional and hard to undo; hstspreload.org itself does not recommend it by default.

   54% of Telecommunications & Internet peers do this.

   Guide: HTTPS and TLS Guide for Website Owners

3. Priority 3 · Enable

   robots.txt published

   Observed: No robots.txt file was returned at the site root.

   What to do: Publish /robots.txt with any crawl rules you need and a Sitemap: line pointing to your XML sitemap.

   88% of Telecommunications & Internet peers do this.

   Guide: Robots.txt Guide: Control Crawling Without Hiding Mistakes

4. Priority 4 · Enable

   XML sitemap discoverable

   Observed: No sitemap was listed in robots.txt or found at /sitemap.xml.

   What to do: Generate an XML sitemap of canonical URLs, reference it in robots.txt and submit it in Google Search Console.

   83% of Telecommunications & Internet peers do this.

   Guide: XML Sitemap Guide: Include Only URLs You Stand Behind

What o2.sk already does well

Practices fewer than half of Telecommunications & Internet peers use.

• DNSSEC signedDNSSEC delegation (DS record) present.13% of peers
• Nameservers spread across providersNameservers spread across more than one operator.16% of peers
• No render-blocking scripts in <head>Head scripts load without blocking.37% of peers

What we saw

Homepage checked

https://www.o2.sk/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

DigiCert, 198-day validity, expiring 2026-11-19

DNS operators

2 self-run or other nameserver domains

DMARC policy

p=quarantine

Homepage HTML

0 KB, uncompressed

Images on homepage

0

Limits: homepage only, one location, one moment. Header checks reflect the homepage response; other pages may differ.

Stack and providers

Seen in the homepage response, certificate and DNS. Provider pages compare how their customers configure the same checks.

All 31 checks

Select a gap for the method and fix. How each check works

Compare with other Telecommunications & Internet sites

• freedatagh.com51
• iliad.it51
• lojavirtualtim.com.br48
• securustech.online48
• tumundo.cl48

Telecommunications & Internet readiness benchmark