Why does creating a Regional NAT Gateway generate a new Route Table with an Edge Association?

In fact, the inbound traffic that the NAT gateway interacts with comes primarily from the devices already within your VPC. That’s likely what the documentation is alluding to with the term "appliance." So even though it seems like a lot, it’s about keeping your traffic organized and efficient.

AWS has created this edge association to streamline several essential functions like centralized egress, manage multi-VPC traffic inspection, and ensure regulatory controls. The best part is that when you start traffic in private subnets, you don’t need to replicate the AWS-created route table because the NAT tracks the state for outbound flows automatically.

Actually, the NAT gateway only lets traffic in from within the VPC, so when the documentation refers to "appliance," it usually means security tools like firewalls. If you don't have advanced inspection setups, you're right—you don’t need that extra ingress route.

A NAT Gateway is generally considered an interface or a gateway in AWS terminology. By having its own route table, the NAT can effectively manage traffic routing more efficiently and avoids complications that might arise if it didn't have a dedicated one.

The edge-associated route table serves a key role in modernizing how public traffic is managed. It essentially functions as the "outside" interface of the NAT gateway, processing outgoing and incoming traffic flows. You also need a separate, internal route table to handle traffic going to and from inside your network.