Under which service model does the cloud provider maintain the operating system, while the user manages applications?

The service model where the cloud provider maintains the operating system while the user manages applications is Platform as a Service (PaaS). In this model, the cloud provider offers a platform that includes the underlying infrastructure, operating systems, and middleware, allowing users to focus on developing, running, and managing their applications without the complexity of managing the OS or hardware.

PaaS is designed to streamline the development process by providing a pre-configured environment equipped with necessary tools and services. This allows developers to deploy applications quickly and efficiently, handling the software stack that supports the runtime environment. Users are responsible for their applications and data, but they benefit from the maintenance of the core services and platform by the provider.

This contrasts with other models. For example, Infrastructure as a Service (IaaS) requires users to manage not only the applications but also the operating system and other components of the infrastructure. Software as a Service (SaaS) fully abstracts the underlying infrastructure and application management, providing users with access to completed software solutions without any management responsibilities.

By picking Platform as a Service, you understand the shared responsibility model, where the cloud provider handles certain layers of the stack, reducing overhead for users to concentrate on application development and deployment.