What should the solutions architect do to meet these requirements?
Create a gateway endpoint for Amazon S3 in the VPC. In the route tables for the private subnets, add an entry for the gateway endpoint.
Create a single NAT gateway in a public subnet. In the route tables for the private subnets, add a default route that points to the NAT gateway.
Create an AWS PrivateLink interface endpoint for Amazon S3 in the VPIn the route tables for the private subnets, add an entry for the interface endpoint.
Create one NAT gateway for each Availability Zone in public subnets. In each of the route tables for the private subnets, add a default route that points to the NAT gateway in the same Availability Zone.
Explanations:
Creating a gateway endpoint for Amazon S3 allows EC2 instances in private subnets to access S3 without routing traffic over the internet, minimizing data transfer costs and enhancing security. The endpoint provides a direct route to S3, avoiding NAT gateways and reducing costs associated with internet data transfers.
Using a single NAT gateway in a public subnet would route traffic from private subnets to the internet for accessing S3, which incurs data transfer costs for both the inbound and outbound traffic. This option does not optimize for cost efficiency when accessing S3.
AWS PrivateLink is typically used for accessing AWS services privately over a secure connection. However, S3 does not support interface endpoints for data access in this manner; instead, gateway endpoints are the correct option for accessing S3 from private subnets.
While having multiple NAT gateways in each Availability Zone provides redundancy and can improve availability, it still routes S3 traffic through the internet, which leads to unnecessary data transfer costs. This does not meet the requirement for optimizing network architecture for cost efficiency.