A large telecom company has created Fifteen VPC in different regions for deploying its IT servers. This VPC is created for each department like Accounts, Finance, Sales, Pre-Sales, HR. A Central VPC is created which host servers accessed from all other VPC. There is an additional requirement of servers in Accounts VPC communicating with servers in Finance VPC. IT Head wants you to ensure proper isolation between VPC & no additional reachability, including the internet, should be established. Which of the following solution will meet this requirement?

Answer options:

A.Create a Partial Mesh configuration on VPC Peering between Central VPC & all other VPCs. Create an additional VPC Peering between Accounts & Finance VPC for communication between them.
B.Create a Full Mesh configuration on VPC Peering between all VPCs.
C.Create Partial mesh configuration on VPC peering between Central, Finance & Accounts VPC. Create a full VPC peering between Central VPC & all other VPC.D.Create a VPN Connection between instances in Accounts & Finance VPC. Create a partial VPC peering between Central VPC & all other VPC.

Correct Answer – A
Partial mesh configuration on VPC can be used to connect VPC with Central VPC so that all VPC can connect to servers in central VPC. With Partial Mesh configuration on VPC, there would not be communication between all other VPCs. Since there are additional connectivity requirements between Finance & Account VPC, an additional peering can be established between these two VPC.Option B & Care incorrect as creating a full mesh configuration between all VPC will allow communication between all VPC.Option D is incorrect as a VPN connection will be internet which is against the requirement.
 For more information on VPC Peering options, refer to the following URLs
https://aws.amazon.com/answers/networking/aws-multiple-region-multi-vpc-connectivity/
https://aws.amazon.com/answers/networking/aws-single-region-multi-vpc-connectivity/