Private Versus Public Cloud Computing
A plethora of applications are being considered for the cloud, but it may take at least another year before cloud computing goes mainstream in the enterprise.
The public cloud argument in the ongoing debate versus private clouds goes something like this: Only the public cloud can provide the scalability to meet burgeoning data environments, so private clouds are a waste of money that limit you to your own finite infrastructure.
Ah, but what fun we can have with that infrastructure once it takes on the trappings of the cloud.
At its heart, this debate is over the difference between PaaS and IaaS. Infrastructure as a service is essentially concerned with providing the underlying resources to support compute platforms and the tools needed to run applications. The public cloud is best suited for providing IaaS precisely because of its high scalability. Platform as a service, however, is concerned with delivering primarily virtualized computing environments across one or more clouds. So whether those clouds are public or private is of little concern; it only has to be cheap and capable of meeting service requirements.
To date, however, there's been a problem with PaaS: Most platforms are tied to a single IaaS environment. VMware's Cloud Foundry, for example, only works on Amazon Web Services, so if you want to invite, say, Rackspace to the party, you had to build a completely separate PaaS, much like the old silo days of static infrastructure.
Fortunately, that is coming to an end as VMware announced that Cloud Foundry is now open to any instance from any cloud provider. That means apps need only be deployed once and they will run anywhere you choose without any additional coding or migration hassles across infrastructures.
We're starting to hear the same thing from Microsoft, but in a different direction. Windows Azure offers a truly powerful distributed architecture for .NET environments, but it is of only limited value in mixed environments. Coming soon, though, is a new Azure virtual machine that supports not only Windows Server, SharePoint and SQL, but Linux as well. It's not exactly a universal system, but it does indicate that Microsoft is willing to add greater IaaS support on its PaaS platform.
At the same time, it seems that Amazon, at least, is not interested in getting into the PaaS game itself, preferring instead to be as open and flexible to multiple third-party providers as possible. At best, the company will continue to dabble with its Elastic Beanstalk system, which facilitates the upload of applications into the cloud but doesn't provide the actual working environment. As CTO Werner Vogels told ZDNet the other day, the company is committed to building an infrastructure that enables "1,000 platforms to bloom."
So does the private cloud on its own provide additional resources to meet data requirements? No. Does it introduce a level of flexibility that allows you to manage your resources much more efficiently and effectively? Absolutely. And it's for that reason it should be a vital component of the enterprise cloud infrastructure.