AWS Certified Advanced Networking – Specialty (ANS-C01) — Question 224

A company has a VPC that includes application workloads that run on Amazon EC2 instances in a single AWS Region. The company wants to use AWS Local Zones to deploy an extension of the application workloads that run in the Region. The extended workloads in the Local Zone need to communicate bidirectionally with the workloads in the VPC in the Region.

Which solution will meet these requirements MOST cost-effectively?

Answer options

• A. Create a new VPC in the Local Zone. Attach all the VPCs to a transit gateway. Configure routing for the transit gateway and the VPCs. Deploy instances in the new VPC.
• B. Deploy a third-party appliance in a new VPC in the Region. Create a new VPC in the Local Zone. Create VPN connections to the appliance for the VPCs. Deploy instances in the new VPC in the Local Zone.
• C. Create a new subnet in the Local Zone. Deploy a third-party appliance in the VPC with interfaces in each subnet. Configure the new subnet to route the Local Zone through the appliance. Deploy instances in the new subnet.
• D. Create a new subnet in the Local Zone. Configure the new subnet to use a CIDR block that is within the VPC’s CIDR block. Deploy instances in the new subnet in the Local Zone.

Correct answer: D

Explanation

Option D is the most cost-effective solution because it allows for direct communication between the Local Zone and the VPC without the need for additional infrastructure like transit gateways or third-party appliances. The other options involve more complexity and cost due to the added components and configurations required, making them less efficient for the given requirements.