Putting Platform as a Service on a Pedestal

There isn’t only one approach to PaaS. In fact, the lines between Platform as a Service and Infrastructure as a Service can blur as well. But for purposes of getting your head around platforms that help you develop applications in the cloud, we separated Infrastructure as a Service. Platform as a Service has many characteristics worth mentioning.

Consider what all PaaS solutions have in common:
✓ PaaS has to leverage the Internet.

✓ PaaS must offer some type of development language so professional developers (and in some cases users) can add value.

✓ These environments need a way to monitor and measure resource use and to track overall performance of the vendor’s platform.

✓ Almost all PaaS platforms are based on a multi-tenancy architecture (which lets multiple clients run their copy separately from each other through virtualization) so that each customer’s code or data is isolated from others.

✓ A PaaS environment needs to support the development lifecycle and the team development process, including testing.

✓ A PaaS platform needs to include services interfaces such as SOAP (Simple Object Access Protocol) and XML (eXtensible Markup Language), among others.

✓ A PaaS platform must be able to deploy, manage, test, and maintain the developed applications.

✓ A PaaS platform must support well-defined and well-documented interfaces so elements and components can be used in the following:

• Composite applications are created by combining services to create an enterprise application based on orchestration of business logic and rules.

• Portals, which are an organized environment that organizes application components for the customer.

• Mashups, which let end users easily bring together two or more business services that can communicate and exchange data.

Although PaaS platforms have some common characteristics, we think there are some different approaches that are appropriate for different needs. We have divided the environments into three categories:

✓ Integrated lifecycle platform
✓ Anchored lifecycle platform
✓ Enabling technologies as a platform

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