What is PaaS?

Experts explain growing role in 'as a service' family

Like the youngest child in just about any family, Platform as a Service (PaaS) is getting plenty of attention today -- but experts say it's still got a way to go before it catches up with its older siblings, Infrastructure as a Service (IaaS) and Software as a Service (SaaS).  

And although PaaS is steadily becoming more popular, if you ask five cloud-computing professionals "What is PaaS?" you're still likely to get five different answers.   

"Without any doubt, use of PaaS is growing," said Yefim Natis, vice president and distinguished analyst at Stamford, Conn.-based Gartner Inc. "But PaaS is smaller and younger than IaaS and SaaS, and it also suffers from a lot of confusion."

Part of that confusion stems from a lack of consensus on what exactly PaaS is supposed to do. In fact, PaaS is often used for myriad types of projects within the same organization, according to results from the latest TechTarget Cloud Pulse Survey.

The many faces -- and uses -- of PaaS

While the majority of Cloud Pulse survey respondents said they use PaaS to develop and deploy cloud applications (58.7%), nearly half of respondents (49.6%) said they use it to extend SaaS applications such as Salesforce.com and SAP. At the same time, 48% reported using PaaS as an application-testing environment, and just over 41% said they use it to develop and deploy mobile applications.

PaaS is smaller and younger than IaaS and SaaS, and it also suffers from a lot of confusion.

Yefim Natis, Gartner Inc.

Despite its apparent versatility, PaaS was designed for one thing, said John Rymer, vice president and principal analyst at Cambridge, Mass.-based Forrester Research. His response to the "What is PaaS" question: "PaaS is for cloud apps. That's what it was invented for."

Still, many companies new to cloud applications mistakenly view PaaS as an extension of other service models, such as IaaS and SaaS, Rymer said.

"PaaS has really become problematic because [the term is used to] apply to so many things that are so very different," he said, noting that many people think they're using PaaS when they're using something else.

As an example, Rymer pointed out that Amazon Web Services (AWS) is currently the most widely used cloud platform. The catch: AWS isn't technically a PaaS.

"People might take Amazon Web Services and put IBM WebSphere on top of it, or just sign up through a Windows virtual machine and use .NET," explained Natis. "Since they're able to be programming in the cloud, they think it must be PaaS."

But having to deal with virtual machines is a characteristic of IaaS, he said. If AWS were truly a PaaS, all of the infrastructure would be hidden.

Such mix-ups may be hindering PaaS adoption rates. "People need to build trust in PaaS," said Fima Katz, CEO of Exadel, a global software engineering company. "We don't expect people are going to switch completely to PaaS right away. What we see is that a lot of people are using PaaS on some portion of their infrastructure. They're starting to try it and, as soon as they see success, then use it on another application, and so on."

PaaS on the rise -- with some big-name backers

Meanwhile, the PaaS market is expanding. Up until late 2012, some of the largest technology players (who may well have been still trying to answer that "What is PaaS" question themselves) had yet to enter the fray—for example, IBM, Red Hat and HP didn't have PaaS offerings. Today, all three do.

But Rymer cautions against the hype surrounding PaaS as the "next big thing" in cloud computing.

"People are sitting back and waiting for PaaS to become the biggest of the three," Rymer said, referring to IaaS, PaaS and SaaS. "Forget it. All of these categories are growing because cloud is on the rise. Rising tides float all boats."