You can tell when an industry trend starts hitting the wall: Salespeople stop talking about it. A few sources have told me that, these days, when customers get a sales pitch that leads with "the cloud," they reply with a look that says: "If I hear 'the cloud' out of your mouth one more time, I'm going to kill you," or something to that effect.
Ironically, just when the cloud "brand" is faltering, the real-world value of this fuzzy collection of technologies and techniques is clearer than ever.
Just have a look at four distinct segments of the cloud in order of hotness: The private cloud is on fire -- for very good reasons that will be explained shortly. SaaS (software as a service), almost entirely a public cloud phenomenon, comes next. After that are the public IaaS (infrastructure as a service) offerings such as those from Amazon.com and Rackspace -- and finally commercial PaaS (platform as a service) environments for application development. Let's start at the top.
The allure of the private cloud
You can argue that the whole public cloud phenomenon began years ago when CIOs looked at Google's infinitely scalable, resilient infrastructure and said, "Me want some of that." In response, data center managers slapped their foreheads and explained through clenched teeth that Google's infrastructure was purpose-built for a single application -- utterly the wrong fit for the average data center.
Meanwhile, the proliferation of server virtualization began to form the foundation for a different sort of private cloud. Virtualization's combination of vastly improved hardware utilization and quick provisioning has proven irresistible, to the point where roughly half of servers in midsize to large companies today act as physical hosts to VMs. That's a huge shift from dedicated resources to pooled resources.
When multiple applications run on large banks of virtual servers, the private cloud becomes the most effective way to manage those pooled resources. You need private cloud software to help translate commercial application hardware requirements to VM requirements; to dynamically allocate compute and storage resources among multiple applications; and to accurately charge back stakeholders for the resources they consume. These are not trivial problems -- and without the software to solve them and automate processes, the burden of manually maintaining that shared infrastructure can become too heavy to bear.
Underneath all that, so-called converged infrastructure helps make the private cloud sing. Storage and data share the same high-bandwidth, general-purpose network. Old, dedicated switches get consolidated into programmable 10Gbps switches, so that I/O can be sliced and diced as needed. The sheer number of devices needed to run a data center drops dramatically -- saving not only hardware costs but also management overhead.
The private cloud as it is emerging today may not be what CIOs had in mind originally, but the result can be a massive increase in efficiency and agility.
The return of client/server
Right now, you'd be hard-pressed to find a company that doesn't subscribe to some public cloud service or other. In terms of dollars, the money is still going to SaaS. More will be headed that way if Microsoft has anything to do with it.
By now everyone is familiar with the pure SaaS model -- and the major SaaS providers, including Salesforce.com, NetSuite, Epicor, and Workday. The basic dynamic is the same as it ever was: If you're a small business, SaaS often makes much more sense than the hassle and expense of locally installed and maintained enterprise software. If you're a big business, integrating SaaS into the rest of your existing application and security infrastructure can be tough.
Microsoft's Office 365 exemplifies a different approach -- what might be called the "gateway" model of SaaS, where back-end services in the cloud support locally installed software (Office 2010, in this case). Few customers want to be in the business of maintaining Exchange or SharePoint servers, so why not pay Microsoft to do it? Microsoft obviously sees the gateway model as critical to its future -- and you can expect nearly every conventional software vendor with a foothold in the enterprise to pursue it.
Interestingly, this approach -- much like client/server, only the server resides in the cloud -- also describes the mobile application model. The idea that the client should be a superthin Web app for the sake of cloud purity is ridiculous; it makes sense to run a rich client locally, as long as the local instance can be upgraded on the fly.
Pick your public service
Recently I wrote about how OpenStack and Eucalyptus will enable customers to manage local and cloud-based infrastructure using one set of tools -- so a private cloud can burst to public cloud IaaS and accommodate peak demand. But that's not really happening right now, in part because the APIs are so limited. It's a promising scenario that's maybe three years from taking off.
Meanwhile, enterprises still tend to rent compute and storage from Amazon.com or Rackspace for the usual discrete functions (mainly disaster recovery and dev and test). One new wrinkle is that an increasing number of vendors and professional service organizations are using the public cloud to demo their offerings to large customers. Want to see what your implementation will look like? Let's spin up a couple thousand servers for 24 hours on Amazon and have a look.
As it turns out, PaaS providers are fast becoming major consumers of IaaS. For example, Engine Yard -- the leading Ruby on Rails development platform in the cloud -- uses Amazon and Terremark for its infrastructure. Engine Yard charges a slight premium to its customers for that infrastructure (plus more for support services) and otherwise alows developers to code away free of charge.
As best as I can determine, PaaS is the area of the cloud that appeals least to enterprises. No big surprise there: For what particular reason would you have your developers create intellectual property on someone else's platform? Instead, enterprises tend to have a once-removed relationship with PaaS -- and hire outside development firms to build and deploy public-facing Web apps on PaaS platforms.
There are exceptions to this, of course, an obvious example being the many customers that use the Force.com platform to add to Salesforce's functionality. But for the most part, PaaS is the province of independent developers creating custom or commercial Web and/or mobile applications. The main effect of PaaS on enterprises, then, is that it provides a platform for a new generation of consurmerized applications business users are flocking to -- and IT is desperately trying to manage.
So there's your handy state of the cloud report, summary edition. One final note: I find myself agreeing with InfoWorld's David Linthicum when he says "It's official: 'Cloud computing' is now meaningless." The cloud nomenclature has always been frustratingly vague -- and vendors' tendencies to grandfather everything on earth into "the cloud" has made matters much, much worse. No wonder people are sick of it.
Got ideas for some new terminology? I'd love to hear about it.
This article, "The (real) state of the cloud, 2011," originally appeared at InfoWorld.com. Read more of Eric Knorr's Modernizing IT blog, and for the latest business technology news, follow InfoWorld on Twitter.