AWS Certified Solutions Architect – Associate (SAA-C03) — Question 502

A company needs to connect several VPCs in the us-east-1 Region that span hundreds of AWS accounts. The company's networking team has its own AWS account to manage the cloud network.

What is the MOST operationally efficient solution to connect the VPCs?

Answer options

• A. Set up VPC peering connections between each VPC. Update each associated subnet’s route table
• B. Configure a NAT gateway and an internet gateway in each VPC to connect each VPC through the internet
• C. Create an AWS Transit Gateway in the networking team’s AWS account. Configure static routes from each VPC.
• D. Deploy VPN gateways in each VPC. Create a transit VPC in the networking team’s AWS account to connect to each VPC.

Correct answer: C

Explanation

AWS Transit Gateway acts as a centralized cloud router, making it the most scalable and operationally efficient solution to connect hundreds of VPCs across multiple accounts. Setting up full-mesh VPC peering (Option A) becomes unmanageable at this scale due to the sheer number of connections and routing table limits. Options B and D are less secure and introduce significant management overhead and architectural complexity compared to using AWS Transit Gateway.