Security Groups and NACLs

• Network Access Control List
• Like firewall which control traffic from and to subnets.
• 1 NACL / Subnet.
• Rules have a number, higher precedence with a lower number.
• Last rule is (*) which denies a request, if no rules match.
• New NACLs denies everything; while, default NACL accepts everything.

With Ephemeral Ports