AWS Certified Solutions Architect – Professional (SAP-C02) — Question 152

A company has a latency-sensitive trading platform that uses Amazon DynamoDB as a storage backend. The company configured the DynamoDB table to use on-demand capacity mode. A solutions architect needs to design a solution to improve the performance of the trading platform. The new solution must ensure high availability for the trading platform.

Which solution will meet these requirements with the LEAST latency?

Answer options

• A. Create a two-node DynamoDB Accelerator (DAX) cluster. Configure an application to read and write data by using DAX.
• B. Create a three-node DynamoDB Accelerator (DAX) cluster. Configure an application to read data by using DAX and to write data directly to the DynamoDB table.
• C. Create a three-node DynamoDB Accelerator (DAX) cluster. Configure an application to read data directly from the DynamoDB table and to write data by using DAX.
• D. Create a single-node DynamoDB Accelerator (DAX) cluster. Configure an application to read data by using DAX and to write data directly to the DynamoDB table.

Correct answer: B

Explanation

Option B is the best choice because it utilizes a three-node DAX cluster for reading, which provides faster access, while writing directly to the DynamoDB table ensures data is consistently updated without the extra latency of going through DAX. The other options either reduce the number of DAX nodes or change the read/write configuration, which could introduce higher latency or reduce availability.