Glossary term
What is stateful (Stateful (firewall))?
stateful stands for Stateful (firewall).
Remembers connections: if a request was allowed in, its reply is automatically allowed out. Security Groups are stateful.
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.