docs(checkpoint): complete checkpoint 20 - HTTPS and SSL certificates

[wendev27]

🎯 Objective

Understand how HTTPS and SSL certificates secure communication between browsers and web applications.

📚 Topics Covered

• Nginx
• Reverse Proxy
• HTTP vs HTTPS
• SSL certificates
• Certificate Authorities
• Let's Encrypt
• Certbot

🤔 Questions Explored

• How does Nginx route traffic?
• Why are SSL certificates needed?
• Why does Chrome trust Google but not localhost?
• How do websites automatically renew certificates?

🔬 Labs and Experiments

• Built a reverse proxy with Nginx
• Routed traffic to frontend and backend containers
• Generated self-signed SSL certificates
• Configured HTTPS locally
• Observed browser trust warnings
• Explored certificate authorities

🧠 Key Concepts

• Reverse proxy
• HTTPS
• SSL certificates
• Certificate Authorities
• Automatic certificate renewal

🚀 Next Checkpoint

Phase 6 — Cloud & Orchestration