NAT/NACL

NAT

what is NAT?
-> A set of process – remapping SRC or DST IPs

NAT does IP masquerading – it hides CIDR blocks behind one IP

It gives private CIDR range outgoing internet access

NAT Architecture:

private CIDR blocks will be re-mapped via its Route Table and will be passed to NAT Gateway
NAT Gateway will then be re-mapped and will be passed to Internet GateWay
Ta-da! Public internet access!

NACL

filter what comes in/out of VPC subnet which means connection within a subnet aren’t impacted by NACLs

NACL is stateless, inbound and outbound needs to be specified (if applicable)

each subnet can be associated with one NACL whereas one NACL can be associated with many subnet

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