AWS Certified Solutions Architect – Professional — Question 965

A web design company currently runs several FTP servers that their 250 customers use to upload and download large graphic files They wish to move this system to AWS to make it more scalable, but they wish to maintain customer privacy and Keep costs to a minimum.
What AWS architecture would you recommend?

Answer options

• A. ASK their customers to use an S3 client instead of an FTP client. Create a single S3 bucket Create an IAM user for each customer Put the IAM Users in a Group that has an IAM policy that permits access to sub-directories within the bucket via use of the 'username' Policy variable.
• B. Create a single S3 bucket with Reduced Redundancy Storage turned on and ask their customers to use an S3 client instead of an FTP client Create a bucket for each customer with a Bucket Policy that permits access only to that one customer.
• C. Create an auto-scaling group of FTP servers with a scaling policy to automatically scale-in when minimum network traffic on the auto-scaling group is below a given threshold. Load a central list of ftp users from S3 as part of the user Data startup script on each Instance.
• D. Create a single S3 bucket with Requester Pays turned on and ask their customers to use an S3 client instead of an FTP client Create a bucket tor each customer with a Bucket Policy that permits access only to that one customer.

Correct answer: A

Explanation

Using a single S3 bucket with folder-level partitioning and IAM policy variables (such as '${aws:username}') allows secure, isolated access for multiple clients while keeping S3 costs and administration overhead low. Creating individual buckets for 250 customers is highly inefficient and difficult to manage, while running an Auto Scaling group of FTP servers on EC2 introduces unnecessary compute costs and management complexity. Transitioning clients to an S3-compatible client directly leverages AWS's highly durable and scalable storage without maintaining server infrastructure.