Glossary term
What is allow-listing? Meaning for developers
Block everything, then permit only what you explicitly list. The default behaviour of a Security Group.
Learn it properly · DevOpsLesson 2: Networking Basics: IP, Ports, TCP/UDP and FirewallsHow a browser request actually finds and reaches your server. The layer Vercel hides completely, and the one you must understand before EC2 makes any sense.