N10-009 Question 41
Single answerService models: Software as a service (SaaS), Infrastructure as a service (IaaS), Platform as a service (PaaS)A company is moving a customer-facing web application to the cloud. The development team wants the cloud provider to manage the operating system, runtime, and patching so developers can focus on deploying code. However, the company still needs control over the application itself and its data. Which service model best fits this requirement?
- A
Software as a service (SaaS)
- B
Infrastructure as a service (IaaS)
- C
Platform as a service (PaaS)
- D
Desktop as a service (DaaS)
Show answer and explanation
Correct answer: C
Explanation
The best answer is Platform as a service (PaaS). In cloud shared-responsibility models, PaaS sits between IaaS and SaaS. With IaaS, the customer manages more of the stack, including the operating system and often the runtime environment. With SaaS, the provider manages nearly everything and delivers a finished application to users. PaaS is the appropriate middle ground when an organization wants to deploy its own application code while offloading platform management such as OS maintenance, patching, and runtime support to the provider. This mapping is consistent with common guidance from major cloud providers such as Microsoft Azure, AWS, and Google Cloud, all of which describe PaaS as a model for building and deploying applications without managing underlying infrastructure.
- A. Incorrect.
SaaS is incorrect because in a software-as-a-service model, the provider delivers a complete application to end users, such as email, CRM, or collaboration software. The customer typically manages only limited configuration and user-specific settings, not the deployment of its own custom application code. Someone might choose this if they confuse 'using software in the cloud' with 'hosting a custom-developed application.'
- B. Incorrect.
IaaS is incorrect because infrastructure as a service provides foundational resources such as virtual machines, storage, and networking. In this model, the customer is still generally responsible for managing the operating system, middleware, runtime, and application. This does not meet the requirement that the provider handle the OS, runtime, and patching.
- C. Correct.
PaaS is correct because platform as a service is designed for application deployment without requiring the customer to manage the underlying operating system, middleware, or runtime environment. The provider manages the platform components, while the customer manages the application code and data. This aligns directly with the scenario's need to let developers focus on deploying code rather than maintaining servers.
- D. Incorrect.
DaaS is incorrect because desktop as a service provides hosted virtual desktops to users. It is not the appropriate service model for deploying and running a customer-facing web application. This distractor is plausible because it is also a cloud service model acronym, but it is unrelated to application hosting requirements in this scenario.