NAT Gateways

• You can enable instances in a private subnet to connect to the internet or other AWS services.

• You can prevent the internet from initiating a connection with those instances.

• You are charged for creating and using a NAT gateway in your account.

• If a subnet's traffic is routed to an internet gateway, the subnet is known as a public subnet.

• If a subnet doesn't have a route to the internet gateway, the subnet is known as a private subnet.

• To create a NAT gateway, you must specify the public subnet in which the NAT gateway should reside.

• Each NAT gateway is created in a specific Availability Zone and implemented with redundancy in that zone.