Your company has 2 AWS accounts which has individual VPC’s. These VPC’s need to communicate with each other. The AWS accounts are in different regions. The VPC’s have non-overlapping CIDR blocks. Which of the following would be a cost-effective connectivity option?

Answer options:

A.Use VPN connections.
B.Use VPC peering between the 2 VPC’s.
C.Use AWS Direct Connect.
D.Use a NAT gateway.

Correct Answer: B
The AWS Documentation mentions the following.
A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them privately. Instances in either VPC can communicate with each other as if they are within the same network. You can create a VPC peering connection between your own VPCs, with a VPC in another AWS account, or with a VPC in a different AWS Region.
AWS uses the existing infrastructure of a VPC to create a VPC peering connection; it is neither a gateway nor a VPN connection and does not rely on a separate piece of physical hardware. There is no single point of failure for communication or a bandwidth bottleneck.
Options A and C are incorrect since VPC peering is easier to establish.
Option D is incorrect since this is used for instances in the private subnet to communicate with the Internet.
For more information on VPC peering, please refer to the below URL-
https://docs.aws.amazon.com/vpc/latest/userguide/vpc-peering.html