The core benefit of public cloud computing is the ability to share massive amounts of hardware and software among many consumers. These IT assets can be provisioned on-demand, allowing business units to only pay for the services they use. Cloud computing systems are also expandable on-demand, so companies can scale up to massive levels of computing power when needed.
For many enterprises, though, interest in cloud computing has not come from the use of public cloud, but from the use of private cloud. And this includes the use of private Platform as a Service (PaaS), something I've wrestled with as a concept since it appeared on my radar a few years ago.
Before comparing private versus public PaaS, it's important to understand the definition of Platform as a Service as a technology. PaaS, no matter if it's private or public, provides basic development, deployment and operations capabilities that support the design, coding, testing and management of cloud-based systems. The value of this technology is that it provides your enterprise an alternative to support whatever development tools are in style at the time, including purchasing the servers on which to run them.
Using public PaaS, enterprise IT simply picks a public PaaS provider, subscribes to the service and gets to work. Using private PaaS, there are a few more steps and a few more things to buy. Enterprise IT installs private PaaS software on existing or new hardware, and internal developers leverage private PaaS as they would a public PaaS service.
With trepidation, IT pros look to private PaaS
Many enterprise IT pros have pushed back on the use of public clouds, including public PaaS, citing a variety of reasons -- control, security, compliance, etc. -- and, in some cases, they have a point.
Most public PaaS use over the last few years has come from shadow IT. PaaS provides developers with the ability to access the technology they need to build critical business applications while, at the same time, flying under the radar of IT. Many in corporate IT are running around attempting to get these "rogue cloud" applications under their control.
For these reasons, the private PaaS market has grown in the last few years.
There are several private PaaS technologies on the market, including Apprenda, ActiveState Stackato, Red Hat OpenShift, CumuLogic and CloudBees. All of these technologies take different approaches to providing development technology, including languages, deployment models, testing and operations. However, they all have similar stories when it comes to the benefits of private PaaS.
The apparent benefits of private PaaS include the following:
- Portability to public clouds, or perhaps the ability to create hybrid clouds.This allows an organization to move to public cloud-based platforms when extra capacity is required, or perhaps split the processing between private and public clouds, to become a hybrid cloud.
- The ability to provide a single enterprise cloud development environment.This means there is central control over development operations, including governing the use of development and deployment tools. This has the effect of standardizing enterprise cloud system development.
- The ability to create cloud applications that typically could not exist in public cloud.While many in enterprise IT are a bit too quick to spread fear, uncertainty and doubt around the use of public clouds, in many cases there are indeed good business, legal and technical reasons not to place enterprise applications and data on public clouds. Thus, the use of private alternatives is sometimes the better approach, with a path to public clouds at some point.
But with every up comes a down. And, like all technologies, private PaaS has some pitfalls.
The downside of leveraging private PaaS is that you don't have the same cost benefits you would with public PaaS, considering that you have to purchase, configure and operate the hardware and software required to support the platform. Thus, fundamentally nothing changes from traditional approaches. And, in fact, private PaaS could make this more complex and difficult to manage, considering that existing development technologies typically don't go away.
Despite these drawbacks, private PaaS is here to stay. What's critical around the success of private PaaS technology, however, is its ability to prove itself over the next year or so as a viable alternative to existing internal application development approaches. Private PaaS also needs to prove it's a cost-effective alternative to public PaaS.
About the author
David (Dave) S. Linthicum is the chief technology officer (CTO) and founder of Blue Mountain Labs, an internationally recognized industry expert and thought leader, and the author and co-author of 13 books on computing, including the best-selling Enterprise Application Integration. Dave keynotes at many leading technology conferences on cloud computing, SOA, enterprise application integration and enterprise architecture.
His latest book is Cloud Computing and SOA Convergence in Your Enterprise, a Step-by-Step Guide. Dave's industry experience includes tenures as CTO and CEO of several successful software companies and upper-level management positions in Fortune 100 companies. In addition, he was an associate professor of computer science for eight years and continues to lecture at major technical colleges and universities, including the University of Virginia, Arizona State University and the University of Wisconsin.