Virtual Private Cloud

The Amazon Virtual Private Cloud (VPC) service provides the network backbone for many AWS services. A virtual private cloud is a virtual network in the AWS cloud that’s logically isolated from other networks. The most well-known use of VPCs is connecting EC2 instances together and to other AWS services and networks, including the internet.

When you create an AWS account, Amazon automatically creates a default VPC in each region. The default VPC is configured to allow instances within the VPC to access the internet. This way you don’t have to create and configure your own VPC just to use EC2.

You can create your own nondefault VPCs. Nondefault VPCs are fully isolated from every other network and AWS resource, including other VPCs. This means you’ll have to configure them explicitly if you want them to have access to other networks and AWS resources outside of the VPC.

VPC CIDR Blocks

Each VPC requires a Classless Inter-Domain Routing (CIDR)...