N10-009 Question 40
Single answerService models: Software as a service (SaaS), Infrastructure as a service (IaaS), Platform as a service (PaaS)A company is launching a customer portal and wants to minimize the time its network team spends maintaining the underlying operating systems and middleware. The developers still need to deploy custom application code and use a managed database service. The company does not want to manage virtual machines directly, but it does want more control over the application environment than a fully hosted email or file-sharing product would provide. Which cloud 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 standard cloud shared-responsibility models, SaaS offers the least customer control because the provider manages the full application stack, while IaaS offers the most control over infrastructure but requires the customer to manage operating systems and often middleware. PaaS sits between them: the provider manages the platform components, and the customer focuses on deploying application code and configuring the app. This makes PaaS the best fit when an organization wants to avoid managing servers and operating systems but still needs to build and run custom applications. This distinction 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 application development and deployment without direct infrastructure administration.
- A. Incorrect.
SaaS is incorrect because SaaS delivers a complete application to end users, such as hosted email, collaboration tools, or CRM platforms. In this scenario, the developers need to deploy custom application code, which goes beyond simply consuming a finished software product. A candidate might choose SaaS because it reduces management overhead, but it usually does not provide the level of control needed for custom application deployment.
- B. Incorrect.
IaaS is incorrect because IaaS provides foundational compute, storage, and networking resources such as virtual machines, subnets, and load balancers. With IaaS, the company would typically still manage guest operating systems, patching, and much of the middleware stack. That conflicts with the requirement to avoid managing virtual machines directly. This is a common misconception because IaaS does offer flexibility, but it requires more administrative effort than the scenario allows.
- C. Correct.
PaaS is correct because it lets developers deploy and run custom applications without managing the underlying servers, operating systems, and much of the middleware. This aligns with the requirement to reduce infrastructure management while still supporting custom code and managed backend services such as databases. PaaS is designed for organizations that want application-level control without the operational burden of VM administration.
- D. Incorrect.
DaaS is incorrect because Desktop as a Service provides hosted virtual desktops for end users, not an application hosting environment for deploying customer-facing web applications. Someone might select this option by confusing different cloud service acronyms, but DaaS does not meet the development and deployment requirements described in the scenario.