Exam AWS Certified Advanced Networking - Specialty ANS-C01 topic 1 question 149 discussion

VPC peering has no bandwidth limit unlike Transit Gateway (50Gb/s per VPC attachment) https://d1.awsstatic.com/whitepapers/building-a-scalable-and-secure-multi-vpc-aws-network-infrastructure.pdf "No bandwidth limits — With Transit Gateway, Maximum bandwidth (burst) per Availability Zone per VPC connection is 50 Gbps. VPC peering has no aggregate bandwidth. "

The correct answer is: A. Configure a transit gateway, attach each VPC to it, and use static routing in each VPC to route traffic to the transit gateway.

No bandwidth limits — With Transit Gateway, Maximum bandwidth (burst) per Availability Zone per VPC connection is 50 Gbps. VPC peering has no aggregate bandwidth. Individual instance network performance limits and flow limits (10 Gbps within a placement group and 5 Gbps otherwise) apply to both options. Only VPC peering supports placement groups.

It doesn't ask about scalability or management, it asks about the HIGHEST throughput -> B

Answer is A VPC peering does not require static routes to be setup Transit gateway peering provides connectivity to all VPCs and its high throughput

Answer is A. VPC routing is non-transitive, how do you route across all VPC. This what Transit Gateways solves

Answer is A. VPC routing is non-transitive, how do you route across all VPC. This what Transit Gateways solves

In this case, configuring a transit gateway and attaching each VPC to it will provide the highest throughput. The transit gateway allows for more efficient routing of traffic between VPCs compared to VPC peering or Site-to-Site VPN connections. Option B (VPC peering) has limitations on bandwidth and does not scale as well when compared to a transit gateway. Option C (transit VPC with VPN connections) can introduce additional complexity and may not provide as high throughput as a transit gateway. Option D (AWS Site-to-Site VPN connections between each VPC) may work but can introduce additional latency and may not scale as well as a transit gateway. Therefore, option A is the preferred solution for achieving the highest throughput and efficient connectivity between the VPCs.

Non clear correct answer. I think it could be B, better than A.

VPC peering is free and also no bandwidth limit compared to 50Gbps limit for a TGW attachment

https://docs.aws.amazon.com/vpc/latest/peering/what-is-vpc-peering.html There is no single point of failure for communication or a bandwidth bottleneck.

Transit gateways are designed for high bandwidth and low-latency communication, making them an ideal choice for scenarios where high throughput between multiple VPCs is required. Each attachment to the transit gateway can support up to 50 Gbps of bandwidth, and multiple VPCs can share the same transit gateway without any direct peering relationship between them.

Maximum bandwidth per VPC attachment, AWS Direct Connect gateway, or peered transit gateway connection, Up to 50 Gbps