An IT manager is evaluating cloud service models for deploying a new customer relationship management (CRM) application. The team wants to retain full control over the operating system, middleware, and application runtime, but does not want to manage the underlying hardware, virtualization, or networking infrastructure. Which cloud service model would best fit these requirements?
- ASoftware as a Service (SaaS)
- BFunction as a Service (FaaS)
- CInfrastructure as a Service (IaaS)
- DPlatform as a Service (PaaS)
Show answer & explanationAnswer & explanation
Correct answer: D. Platform as a Service (PaaS)
Platform as a Service (PaaS) provides a complete development and deployment environment in the cloud, with resources that enable customers to deliver everything from simple cloud-based apps to sophisticated, cloud-enabled enterprise applications. The cloud provider manages the underlying infrastructure (hardware, OS, middleware, runtime), while the customer manages the applications and data.
Why the other options are wrong
- A. SaaS provides a complete, ready-to-use application; the customer has almost no control over the underlying stack.
- B. FaaS (serverless computing) is a subset of PaaS, where the provider manages even more, down to individual function execution, giving less control than requested.
- C. IaaS provides virtualized computing resources; the customer is responsible for managing the OS, middleware, and runtime, which is more control than desired.
Platform as a Service (PaaS)
PaaS is a cloud computing service model that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app. It sits between IaaS and SaaS.
- Provider manages hardware, OS, middleware, runtime.
- Customer manages applications and data.
- Ideal for developers who want to focus on coding, not infrastructure.
- Examples: Google App Engine, AWS Elastic Beanstalk, Heroku.
Memory trick: I-P-S: 'I' control hardware, 'P' control apps, 'S' control nothing.