220-1101 Question 376
Single answerCloud characteristicsA small accounting firm uses a cloud-based tax application during filing season. For most of the year, only a few employees use the service, but from January through April the number of users increases sharply and the firm temporarily needs much more computing capacity. The office manager wants a cloud solution that can automatically increase resources during peak demand and then reduce them afterward so the company pays only for what it uses. Which cloud characteristic best matches this requirement?
- A
Rapid elasticity
- B
Measured service
- C
Resource pooling
- D
Broad network access
Show answer and explanation
Correct answer: A
Explanation
The best answer is rapid elasticity because the key business need is to handle large temporary increases in demand and then release those resources when they are no longer needed. In the NIST essential characteristics of cloud computing, rapid elasticity describes the ability to provision and release resources quickly, often automatically, to scale with workload changes. Measured service is related and explains the pay-for-usage billing model, but it does not by itself guarantee dynamic scaling. Resource pooling and broad network access are also standard cloud characteristics, yet they do not directly solve the firm's seasonal capacity problem.
- A. Correct.
Correct. Rapid elasticity is the cloud characteristic that allows resources such as compute power, memory, or storage to scale up quickly when demand increases and scale back down when demand drops. In this scenario, the firm's seasonal workload requires temporary expansion and contraction of resources, which is exactly what rapid elasticity provides.
- B. Incorrect.
Incorrect. Measured service refers to metering cloud usage so customers can be billed based on consumption, such as storage used, network bandwidth, or processing time. Although the scenario mentions paying only for what is used, the main requirement is the ability to automatically scale capacity up and down, which is rapid elasticity rather than measured service.
- C. Incorrect.
Incorrect. Resource pooling means the cloud provider serves multiple customers using a shared pool of computing resources that are dynamically assigned as needed. This is a core cloud characteristic, but it does not specifically describe automatic scaling for seasonal spikes in demand.
- D. Incorrect.
Incorrect. Broad network access means cloud services are available over the network and can be accessed from different client platforms such as laptops, tablets, and smartphones. That characteristic is useful for accessibility, but it does not address changing capacity based on workload.