Platform as a service (PaaS) is a cloud computing service model that lets users, most often developers, rent virtualized servers and other tools used in developing, managing and testing applications.
Similar to Software as a Service (SaaS), PaaS is made available to users over the Internet, although in some instances PaaS software is downloaded and installed locally, making the “as a service” aspect of the name a misnomer.
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Who is involved in the Platform as a Service market?
Beginning in 2011, there has been a host of vendors fighting for position in the PaaS market. While many had developed platforms before that, by the end of 2011 there were very few major technology vendors not involved in the market.
Amazon, Microsoft (with its Azure product) and Google are often identified as market leaders, as is Salesforce.com. There are numerous other platforms, both major companies and independent startups, that complete the market. Examples include CloudBees, Engine Yard, Cloud Foundry, dotCloud and Apprenda.
How is Platform as a Service used for cloud application development?
Platform as a Service has many uses across the cloud application development lifecycle. Some have cloud integrated development environments, or IDEs, and integration with social coding networks like GitHub that allow for easy development in the cloud. Some take all the provisioning, load balancing and other menial work out of testing, and others are geared toward moving existing applications into the cloud, hiding the underlying architectural complexity. Another common use for PaaS is for rapid deployment.
How is Platform as a Service implemented?
One of the misnomers about PaaS is the “as a service” part, because many platforms are not offered that way. Some platforms are downloaded and installed on servers and then run like traditional middleware. Others are offered as a service through a browser. Implementation time obviously varies between the two, with some requiring installation and possibly help from professional services, while others are as simple as creating a log-in.
How does Platform as a Service cut down on testing time?
PaaS fits into the “DevOps” strategy of IT, eliminating the barrier between development and operations. PaaS eliminates the need to provision and build a testing environment, keeps developers from having to go to IT before running tests and, with continuous integration tools, developers can now test as they build without losing time.
What is the difference between multi-language and single-language platforms?
The PaaS offerings from traditional legacy vendors have been largely multi-language, either through design or acquisition. Many of the startups have focused on one language or on minor variations of the same language.
Multi-language enthusiasts argue that one enterprise will want to use different languages for different things and that some complex applications are written in more than one language. Single-language evangelists believe that their platforms are deeper and offer the developer a more focused workspace.
What is lock-in?
Lock-in refers to the inability of customers to port their applications from one platform to another. Whether applications are developed with a PaaS or deployed into one, code from the platform is included in the application. That makes it difficult to move applications between clouds if the need arises. Many vendors have signaled that their platforms no longer lock users in, but the technology has not necessarily changed enough to make the slogan reality.