An internet gateway is a horizontally scaled, redundant, and highly available VPC component
that allows communication between instances in your VPC and the internet. It therefore
imposes no availability risks or bandwidth constraints on your network traffic
An internet gateway serves two purposes: to provide a target in your VPC route tables for
internet-routable traffic, and to perform network address translation (NAT) for instances
that have been assigned public IPv4 addresses
You cannot use an Internet Gateway as a bastion host, deploy an EC2 instance in a public
subnet for this purpose
You cannot connect instances in a private subnet to the Internet using an Internet Gateway,
you need a NAT Gateway or NAT Instance for this purpose
You cannot use the Internet Gateway for making VPN connections to a VPC, you need a Virtual
Private Gateway for this purpose