AWS Certified Solutions Architect – Professional — Question 751

A company has millions of objects in an Amazon S3 bucket. The objects are in the S3 Standard storage class. All the S3 objects are accessed frequently. The number of users and applications that access the objects is increasing rapidly. The objects are encrypted with server-side encryption with AWS KMS keys (SSE-KMS).

A solutions architect reviews the company's monthly AWS invoice and notices that AWS KMS costs are increasing because of the high number of requests from Amazon S3. The solutions architect needs to optimize costs with minimal changes to the application.

Which solution will meet these requirements with the LEAST operational overhead?

Answer options

• A. Create a new S3 bucket that has server-side encryption with customer-provided keys (SSE-C) as the encryption type. Copy the existing objects to the new S3 bucket. Specify SSE-C.
• B. Create a new S3 bucket that has server-side encryption with Amazon S3 managed keys (SSE-S3) as the encryption type. Use S3 Batch Operations to copy the existing objects to the new S3 bucket. Specify SSE-S3.
• C. Use AWS CloudHSM to store the encryption keys. Create a new S3 bucket. Use S3 Batch Operations to copy the existing objects to the new S3 bucket. Encrypt the objects by using the keys from CloudHSM.
• D. Use the S3 Intelligent-Tiering storage class for the S3 bucket. Create an S3 Intelligent-Tiering archive configuration to transition objects that are not accessed for 90 days to S3 Glacier Deep Archive.

Correct answer: B

Explanation

Using server-side encryption with Amazon S3 managed keys (SSE-S3) removes the AWS KMS request charges entirely, directly addressing the cost issue with minimal operational overhead when combined with S3 Batch Operations. SSE-C and AWS CloudHSM options increase operational complexity and management overhead significantly. Transitioning to S3 Intelligent-Tiering and S3 Glacier Deep Archive is inappropriate because the objects are frequently accessed and it does not resolve the KMS request cost issue.