Question 1
An architect is validating an enterprise AWS migration plan, the decisive constraint is: A corporation must route traffic among 80 VPCs without managing thousands of bilateral peering links. What is the most appropriate design under these constraints?
Explanation
Correct Answer
Attach the VPCs to an AWS Transit Gateway with explicit route tables. Transit Gateway provides a transitive hub and reduces the VPC peering mesh.
Incorrect Answers
For the separate situation An existing VPC peering relationship connects two VPCs, and a third VPC needs to reach the peer through one of them, Add a direct peering link or use a Transit Gateway rather than relying on the intermediate peer could be useful. VPC peering does not support transitive routing through a peer VPC.
Peer the regional Transit Gateways and configure the peering routes solves the related scenario An organization needs inter-Region routing between centrally connected VPC groups; transit Gateway inter-Region peering links regional transit domains without a full mesh.
Although Use dedicated spoke and shared-services Transit Gateway route-table associations and propagations can be valid when A shared-services VPC must be reached from every spoke but spokes must not reach each other, it targets a different technical condition. Segmented transit route tables allow hub-service reachability without spoke-to-spoke routing.