I am aware that we can create a vpc by providing a ipv4 cidr range . Imagine I have two AWS accounts with cidr range 10.0.0.0/16 in same region. How are these two VPCs differentiated ? . Might be a dumb question for some . But it would be of great help if you can help me to understand .
Thanks
Base on AWS VPC documents:
A virtual private cloud (VPC) is a virtual network dedicated to your AWS account. It is logically isolated from other virtual networks in the AWS Cloud. You can launch your AWS resources, such as Amazon EC2 instances, into your VPC. You can specify an IP address range for the VPC, add subnets, associate security groups, and configure route tables.
A subnet is a range of IP addresses in your VPC. You can launch AWS resources into a specified subnet. Use a public subnet for resources that must be connected to the internet, and a private subnet for resources that won't be connected to the internet. For more information about public and private subnets, see VPC and Subnet Basics.
To protect the AWS resources in each subnet, you can use multiple layers of security, including security groups and network access control lists (ACL). For more information, see Security.
So, it's like the Local network in each company, the different AWS account isolated like that. When you want to connect two LAN, your option is tunneling and network route between them. Also, you can do same on AWS too.
Finally, for more information read the VPC docs: https://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Introduction.html https://aws.amazon.com/vpc/faqs/