AWS Certified Solutions Architect – Associate (SAA-C03) — Question 782

A company is planning to migrate data to an Amazon S3 bucket. The data must be encrypted at rest within the S3 bucket. The encryption key must be rotated automatically every year.

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

Answer options

• A. Migrate the data to the S3 bucket. Use server-side encryption with Amazon S3 managed keys (SSE-S3). Use the built-in key rotation behavior of SSE-S3 encryption keys.
• B. Create an AWS Key Management Service (AWS KMS) customer managed key. Enable automatic key rotation. Set the S3 bucket's default encryption behavior to use the customer managed KMS key. Migrate the data to the S3 bucket.
• C. Create an AWS Key Management Service (AWS KMS) customer managed key. Set the S3 bucket's default encryption behavior to use the customer managed KMS key. Migrate the data to the S3 bucket. Manually rotate the KMS key every year.
• D. Use customer key material to encrypt the data. Migrate the data to the S3 bucket. Create an AWS Key Management Service (AWS KMS) key without key material. Import the customer key material into the KMS key. Enable automatic key rotation.

Correct answer: B

Explanation

AWS KMS customer managed keys support automatic annual key rotation, which completely automates the process with minimal operational overhead once enabled. SSE-S3 managed keys do not offer customizable annual rotation schedules, and manual rotation introduces unnecessary administrative tasks. Additionally, AWS KMS keys with imported key material do not support automatic key rotation, making the customer managed key with automatic rotation the ideal solution.