HTTP/HTTPS: applications and diagnosis

Objectives and progression

A technical course with six modules, explained decisions, and fictional APS cases. Interpret requests and responses, retries, concurrent updates, caching, message framing, HTTP/2 and HTTP/3, TLS identity, and proxy metrics. References IETF, NGINX, and curl. Internal assessment of 24 decisions in 60 minutes. Independent content without external certification; illustrative examples without executed labs.

Audience: APS L2/L3 teams, middleware administrators, developers, and technical managers.

Prerequisites: TCP/IP and DNS fundamentals; examples provide the context needed for decisions.

300 estimated study minutes

• Identify the service, format, and outcome the test should observe.
• Relate HTTP meaning to decisions that preserve business state.
• Choose reuse rules without confusing performance and data isolation.
• Interpret sizes, truncation, and transport differences between HTTP versions.
• Retain name verification and identify where each TLS connection terminates.
• Combine statuses, metrics, and limits to choose the next observation.

Modules

1. The request and intended representation
2. Methods, statuses, and controlled retries
3. Caching, variants, and validation
4. Versions and message framing
5. HTTPS, identity, and proxy hops
6. Diagnosis and time budgets

Continue learning

Technical assessments

• TCP/IP
• DNS
• Middleware
• Application Production Support

References and version

DR HTTP/HTTPS 2026-09; HTTP RFCs 9110–9114; selected TLS 1.3 and NGINX/curl guidance

• HTTP Semantics · 2026-09-30
• HTTP Caching · 2026-09-30
• HTTP/1.1 framing · 2026-09-30
• HTTP/2 transport mapping · 2026-09-30
• HTTP/3 transport mapping · 2026-09-30
• Additional HTTP status codes: rate limiting · 2026-09-30
• HTTP Strict Transport Security · 2026-09-30
• TLS 1.3 · 2026-09-30
• Service Identity in TLS · 2026-09-30
• curl command-line manual · 2026-09-30
• curl TLS certificate verification · 2026-09-30
• curl response and transfer interpretation · 2026-09-30
• curl write-out diagnostics · 2026-09-30
• NGINX proxy module · 2026-09-30
• NGINX TLS module · 2026-09-30
• NGINX access logging · 2026-09-30
• NGINX upstream response timing · 2026-09-30
• NGINX request and virtual host selection · 2026-09-30
• NGINX core HTTP handling · 2026-09-30
• NGINX HTTPS server configuration · 2026-09-30