AWS: VPC routing rules and limitation

Each subnet must reside entirely within one Availability Zone and cannot span zones

https://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Subnets.html

Address Space: 10/16

VPC: 10/16 ( R1) = sub1: 10.0.1/24 (R1/AZ1) + sub2: 10.0.2/24 (R1/AZ2) + sub3: 10.0.3/24 (R1/AZ3)      (R1= Region 1, AZ1= Availability Zone 1)

VPC to Customer premises:

AWS Direct Connect or

VPN connections from on-premises


connecting VPCs in different AWS Regions using either

AWS-managed networks or

non-AWS networks ( Private network/Internet-ISP = AWS Direct Connect or VPN connection )


Single Region Multi-VPC Connectivity

https://aws.amazon.com/answers/networking/aws-single-region-multi-vpc-connectivity/


Multiple Region Multi-VPC Connectivity

https://aws.amazon.com/answers/networking/aws-multiple-region-multi-vpc-connectivity/

VPC Peering

networking connection between two VPCs  ( between your own VPCs ( same/different Region)  or  with a VPC in another AWS account )

    https://docs.aws.amazon.com/vpc/latest/peering/what-is-vpc-peering.html

https://docs.aws.amazon.com/AmazonVPC/latest/PeeringGuide/peering-configurations-full-access.html#two-vpcs-full-access