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πŸ“˜ Excessive Explanation

🧩 Technical Details

What this tool checks

  • HTTP/2 readiness from TLS/ALPN-compatible path evidence.
  • HTTP/3 confirmation via runtime support path with safe fallback logic.
  • Alt-Svc advertisement visibility where full confirmation is unavailable.

How to read the output

  • Result Summary shows combined protocol posture status.
  • Overview distinguishes confirmed support from advertised-only state.
  • Technical Details includes detection evidence and negotiation notes.
  • Raw Output helps track regression after edge or CDN updates.

Common failure patterns

  1. HTTP/3 advertised but QUIC listener blocked or not deployed.
  2. HTTP/2 disabled unintentionally at edge termination layer.
  3. Region-specific rollout creates inconsistent client experience.
  4. TLS policy prevents expected ALPN negotiation outcomes.

Remediation workflow

  1. Confirm HTTP/2 enablement at all active edge routes.
  2. Validate UDP reachability and QUIC listener deployment for HTTP/3.
  3. Re-test from multiple regions after rollout waves.
  4. Track protocol posture in release validation checklist.

Next steps

❓ Frequently asked questions

Is Alt-Svc enough proof of HTTP/3 support?

No. Advertisement must be validated with confirmed protocol connectivity.

Does HTTP/3 replace HTTP/2 everywhere?

Not yet. Many clients and intermediaries still rely heavily on HTTP/2.

Can protocol support vary by geography?

Yes. Edge rollout and regional policy can create location-specific behavior.

Should performance testing follow this check?

Yes. Availability checks confirm support, not end-user performance outcomes.

When should protocol checks be repeated?

After CDN, TLS, load balancer, or network policy changes.