A VPC peering connection helps you to facilitate the transfer of data. For example, if you
have more than one AWS account, you can peer the VPCs across those accounts to create a file
sharing network. You can also use a VPC peering connection to allow other VPCs to access
resources you have in one of your VPCs
An internal ELB will not help you to transfer data between accounts
You cannot peer subnets
Configuring matching CIDR address ranges will not mean you can route between accounts. Also,
you cannot peer with an account with a matching (or overlapping) address range