An IoT application collects data from a large number of devices and uses DynamoDB to store the data. Due to variable and unpredictable workloads, short bursts of traffic spikes occur resulting in throttling of requests on the DynamoDB table. What is the optimal solution to this problem?

Answer options:

A.Increase provisioned capacity on the DynamoDB table.
B.Configure DynamoDB Auto-Scaling.
C.Configure CloudWatch alarm on DynamoDB utilization. Use the CloudWatch alarm to trigger a Lambda function to scale-up the DynamoDB capacity.
D.Switch the DynamoDB table to on-demand capacity mode.

Answer: D
Option A is incorrect because this is not the most cost-effective solution. It results in an over-provisioned and underutilized DynamoDB table.
Option B is incorrect because it is not the most optimal solution. Auto-scaling is a delayed process and doesn’t work well with short bursts of traffic spikes.
Option C is incorrect because it is not the most optimal solution.It requires additional development and operational overhead for the implementation and maintenance of the Lambda function.
Option D is CORRECT because Amazon`s on-demand capacity mode is the best solution for applications whose database workload is complex to forecast, with large spikes of short duration or average table utilization well below the peak.
Reference:
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/HowItWorks.ReadWriteCapacityMode.html#HowItWorks.OnDemand
https://aws.amazon.com/blogs/aws/amazon-dynamodb-on-demand-no-capacity-planning-and-pay-per-request-pricing/