PaaS is a platform for programming developers and brings the benefits - SaaS is used for but from the software development point. It is the computer platform that provides the facility to use web applications quickly and with ease, without buying & maintaining web-development PaaS has a similarity with that of SaaS except that SaaS deliver software over the web, whereas PaaS provides a platform for the creating of software, delivered over the web. PaaS has a feature of point-and-click tool that allows non-programmers to develop web applications. App-Engine of Google & Force.com, Windows Azure, AppFog, Openshift, and VMware Cloud Foundry are examples of PaaS.
Advantages of PaaS:
- Scalability: of users ranges from hundreds to thousands.
- Prebuilt Business Plan: PaaS vendors provide pre-defined business functionality for users to directly start the project.
- Low Cost: Development via PaaS requires a computer & a good internet connection and hence less investment in hardware & software.
- Instant Community: PaaS providers facilitates user providing online communities where a developer can get new ideas & share their experience & advice.
- Simple & easy to use
Disadvantages of PaaS are as follows:
- Vendor Migration: Migration from one PaaS vendors' application to another PaaS vendor will create some problem.
- Data-Privacy: Privacy of data can get hamper if it is not held within the boundary of the company or organization.
- Mix-up Complexity: Some of the applications developed may be local while others are from the cloud; which may increase the complexity.