Figure 7-1: The software stack as a pyramid.
Understanding Platform as a Service
PaaS is an abstracted and integrated cloud-based environment that supports the development, running, and management of applications. Application components may exist in a cloud environment or may integrate with applications managed in private clouds or in data centers. A primary value of a PaaS environment is that developers don’t have to be concerned with some of the lower-level details of the environment. We expect that most organizations will use a combination of some PaaS with traditional on-premises development environments.
If you look at a software stack as a pyramid, as shown in Figure 7-1, Infrastructure as a Service (IaaS) is at the foundational level and includes capabilities such as operating systems, networks, virtual machines, and storage. In the middle is the PaaS environment that includes services for developing and deploying applications. Software as a Service (SaaS) is at the top of the pyramid representing the actual applications offered to end users.
PaaS vendors create a managed environment that brings together a combination of components that would have been managed separately in a traditional development environment. Services integrated in PaaS include middleware, operating systems, and development and deployment services to support software development and delivery organizations. ...