Internet, NAT, and Egress Gateways
Control how subnets reach the internet in each direction.
Controlling Connectivity
Subnets become public or private based on which gateways their traffic can reach. AWS provides several gateway types, each controlling a different direction of internet access. Understanding them lets you allow exactly the connectivity each tier needs and nothing more.
The Internet Gateway
An internet gateway (IGW) is a horizontally scaled, highly available component that allows two-way communication between a VPC and the internet. A subnet with a route to the IGW is public. Resources also need a public IP or Elastic IP to be reachable from the internet through it.
All lessons in this course
- Public and Private Subnet Design
- Internet, NAT, and Egress Gateways
- Route Tables as Security Controls
- Securing VPC Peering and Transit Gateway