AWS Certified Advanced Networking – Specialty (ANS-C01)Network ImplementationHard
A company is extending its on-premises data center to AWS using a combination of AWS Direct Connect and AWS Site-to-Site VPN for redundancy. They have multiple VPCs in different AWS Regions that need to communicate with the on-premises network. What is the most effective way to centralize and simplify the routing between the on-premises network and all AWS VPCs across multiple Regions?
- AEstablish separate Direct Connect and VPN connections to each VPC in each Region.
- BUtilize a Direct Connect Gateway and associate it with Transit Gateways in each Region.
- CConfigure a custom routing solution using EC2 instances as routers in a central VPC.
- DImplement a Transit Gateway in each Region and peer them together.
Show answer & explanationAnswer & explanation
Correct answer: B. Utilize a Direct Connect Gateway and associate it with Transit Gateways in each Region.
A Direct Connect Gateway allows you to connect your Direct Connect connection to multiple VPCs in different AWS Regions and accounts. By associating the Direct Connect Gateway with Transit Gateways in each Region, you can centralize routing for all VPCs within those Regions to the on-premises network, providing a scalable and simplified architecture.
Why the other options are wrong
- A. This approach would lead to significant operational overhead and complexity, especially with many VPCs and Regions.
- C. Using EC2 instances as routers is a custom, less scalable, and more complex solution compared to AWS managed services for this scale.
- D. Peering Transit Gateways would allow inter-Region VPC communication but would still require a separate mechanism to connect each Regional Transit Gateway to the on-premises network in a centralized manner.
Direct Connect Gateway with Transit Gateway
A combination that allows a single AWS Direct Connect connection to connect to multiple VPCs across different AWS Regions and accounts through Transit Gateways.
- Enables global hybrid connectivity.
- Simplifies routing and network architecture.
- Supports multiple VPCs and AWS accounts.
Memory trick: DX Gateway + TGW = Global Hub for Hybrid Harmony.