o2online.es

Readiness by lane

Green: o2online.es. Thin bar: Telecommunications & Internet peer median.

Priority fixes for o2online.es

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

1. Priority 1 · Accelerate

   HTML compressed

   Observed: The homepage HTML (702 KB) was delivered without gzip, Brotli or zstd compression.

   Why it matters: Compression usually shrinks HTML several times over, so the first bytes of the page arrive sooner on slow connections.

   What to do: Enable Brotli or gzip for text responses (HTML, CSS, JavaScript, JSON, SVG) at the CDN or origin.

   90% of Telecommunications & Internet peers do this. Limit: Read from the homepage response only; other pages or regions may send different headers.

   Guide: How to Set a Website Performance Budget That Teams Can Keep

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 · Harden

   DMARC policy enforces quarantine or reject

   Observed: The DMARC policy for o2online.es was p=none, which asks receivers to take no action on failing mail.

   What to do: Publish DMARC with p=none and a reporting address first, fix any legitimate senders that fail SPF or DKIM alignment, then move to quarantine and finally reject.

   59% of Telecommunications & Internet peers do this.

   Guide: A Practical Website Health Check for Owners

4. Priority 4 · Accelerate

   No render-blocking scripts in <head>

   Observed: The homepage <head> loaded 1 external script without async or defer.

   What to do: Add defer to scripts that need the DOM, async to independent ones such as analytics, or move them to the end of the body.

   37% of Telecommunications & Internet peers do this.

   Guide: Control Third-Party Scripts Before They Control Your Page

What o2online.es already does well

Practices fewer than half of Telecommunications & Internet peers use.

• CAA records limit who can issue certificatesCAA limits issuance to amazon.com, amazonaws.com, amazontrust.com and others.15% of peers
• Referrer-Policy setReferrer-Policy present.33% of peers
• Static files cached for 30 days or moreLong-lived caching on static files.41% of peers

What we saw

Homepage checked

https://o2online.es/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

Amazon, 393-day validity, expiring 2027-03-18

DNS operators

Amazon Route 53

DMARC policy

p=none

Homepage HTML

702 KB, uncompressed

Images on homepage

42 (png 12, webp 9, svg 5)

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

• astrasms.com65
• orange.fr65
• red-by-sfr.fr65
• visible.com66
• yettel.hu66

Telecommunications & Internet readiness benchmark