AWS Certified Advanced Networking – Specialty (ANS-C01)Network ImplementationMedium
A global enterprise has multiple AWS accounts and VPCs spread across different AWS Regions. They need to enable communication between VPCs in different Regions. The solution must be scalable and minimize administrative overhead. Which AWS service should be used?
- AVPC Peering connections between all cross-Region VPCs.
- BAWS Transit Gateway peering across Regions.
- CAWS Global Accelerator to route traffic between Regions.
- DCustom VPN connections between VPCs in different Regions.
Show answer & explanationAnswer & explanation
Correct answer: B. AWS Transit Gateway peering across Regions.
AWS Transit Gateway peering allows you to connect Transit Gateways in different AWS Regions. This enables inter-Region communication between all attached VPCs and on-premises networks through a centralized hub-and-spoke model, which is highly scalable and reduces administrative overhead compared to individual VPC peering or custom VPNs.
Why the other options are wrong
- A. VPC Peering is point-to-point and becomes unmanageable and complex for many cross-Region VPCs (N*(N-1)/2 connections).
- C. AWS Global Accelerator is used to improve application performance for global users by routing traffic to the nearest healthy endpoint, not for direct inter-VPC routing between different regions.
- D. Custom VPN connections between VPCs are less scalable, more complex to manage, and incur higher operational overhead than TGW peering.
Transit Gateway Peering
A feature that connects two Transit Gateways together, allowing network traffic to route between their associated VPCs and on-premises networks across different AWS Regions.
- Connects TGWs in different Regions.
- Enables global network connectivity.
- Simplifies inter-Region routing and management.
Memory trick: TGW Peering: 'Global Highway' for VPCs.