"If you see a bandwagon, it's too late."
Product marketers love a bandwagon, and no bandwagons have been more appealing in the past ten years of information technology (IT) as the Service Oriented Architecture (SOA) and cloud computing ones. Much of the challenge of marketing products is getting the attention of the target customer in order to create an opportunity to pitch products or services to them. Of course, if it doesn't work with one bandwagon, as the old adage goes, try, try again. This is why we often see the same products marketed with different labels and categories applied to them. Product vendors will insist that they have developed some new add-on or tweaked a user interface to include the new concept, but at the very core, the products remain fundamentally unchanged.
It is particularly frustrating when product marketing gets in the way of implementing what otherwise would be a valuable concept. Competing vendor, consultant, and individual implementer messages on the meaning of a specific term interferes with realizing real value. This is especially the case with the emerging concept of private clouds. While the term could potentially have real meaning and lasting value, the product and consulting marketers have turned any potential meaning into mush that hides that value.
Cloud computing is primarily loosely-coupled, location-independent virtualized services run on abstracted infrastructure with the primary intent of reducing IT expenditures, increasing flexibility, or improving overall system robustness. Given that this is the general cloud concept, is there any value in a new concept called private clouds? How does the addition of the word private add value to the service-oriented cloud computing that has been discussed for a handful of years? Is it a valuable term, or mere marketing spin? This article first examines the range of definitions being applied to the private cloud concept, then offers a summary on the value provided by private clouds.
Concept #1: Company-Owned and Operated, Location-independent, Virtualized (Homogeneous) Service Infrastructure
Some are of the opinion that a private cloud consists of infrastructure owned by a company to deploy services in a virtualized, location-independent manner. What differentiates private clouds from simply implementing clustered applications or servers is that the cloud is not built for a specific service or application. Rather, it is an abstracted, virtualized environment that allows for deployment of a wide range of disparate services. In practical terms, companies will most likely not implement this vision of private clouds using a diversity of heterogeneous infrastructure. Indeed, it is in their best interests to control the costs and complexity of support, training, and administration by implementing their private clouds using a single vendor stack. So, this vision of private clouds is often a single-vendor (homogeneous) cluster of virtualized infrastructure that enables location-independent service consumption. Implementing any sort of homogeneous stack reduces the need for loosely-coupled services, and thus weakens the service-oriented cloud computing value proposition as a whole for that company. For most companies, what they used to call grids are now being relabeled as private clouds.
Concept #2: Virtualization Plus Dynamic Provisioning (Elasticity)
Others assert that the above definition doesn't go far enough. In order for the company-owned and implemented infrastructure to be considered a private cloud, it must include the concept of elasticity. Elasticity means that the hardware and software resources must be provisioned in a dynamic manner, scaling up and down to meet changes in demand, thus enabling a more responsive and cost-sensitive approach to IT provisioning. This idea of private clouds sounds a lot like the Utility Computing concept sold as part of IBM's decade-old vision of On Demand Computing. From this perspective, a private cloud is company-owned On Demand Utility Computing implemented with services instead of tightly coupled applications.
Concept #3: Governed, Virtualized, Location-Independent Services
There is a notable contingent that argues that the private cloud is a response to some of the security and governance issues raised by the (public) cloud. Specifically, a private cloud provides more control over what and how. In this regard, a private cloud is a governed cloud that enables virtualized, governed, location-independent services. There has been much consternation over the fact that the most popular public clouds share infrastructure between customers and require that data and communications cross the company firewall. Many IT administrators and managers want the technological benefits of cloud computing without the governance risk of having it reside in someone else's infrastructure. Basically, they want the virtualization, loose coupling, and location-independent benefits of cloud computing without the economic benefits of leveraging someone else's costs and investments. In essence, they would rather own a version of the Amazon EC2 cloud than use it, solely for reasons of governance.
Many are concerned about the governance and security draw-backs of cloud computing. Rather than simply dismissing the economic benefits of public clouds, why not approach private clouds as a veneer placed on top of public clouds? Couldn't companies impose their governance and security requirements on third-party infrastructure, using company-owned governance tools and approaches to manage remote services? Couldn't organizations demand that public clouds provide greater governance and security control? Does the addition of the term private provide the same sort of value as it does in the context of the Virtual Private Network (VPN)? We didn't throw out the Internet because it was insecure and replace it with individual private Internets. So, why should we replace public cloud computing with private clouds?
Concept #4: Internal Business Model for Pay on Demand Consumption of Location-Independent, Virtualized Resources
Some individuals and companies insist that the primary value of any cloud, whether implemented privately or acquired from a public vendor, is the business model of pay-as-you-go service consumption. From this perspective, a private cloud is an internal business model that enables organizations to consume and procure internal, virtualized, loosely-coupled services using a pay-on-demand model similar to a chargeback mechanism. Rather than an IT organization paying for and supporting the costs of the business users in an aggregate fashion, they can provide those resources using the same business models employed by Amazon, Google, Salesforce.com and others in their public clouds. In order to realize this vision of private clouds, companies need a means to enable transactional service purchases, auditing of service usage, and organizational methods for enabling such inter-departmental charges. At the most fundamental level, this vision of the private cloud treats IT as a business and a service provider to the rest of the organization.
Concept #5: Marketing Hype, Pure and Simple
TechTarget offers the most cynical view of the private cloud. In their words, a private cloud is a "marketing term for a proprietary computing architecture that provides hosted services to a limited number of people behind a firewall. Marketing media that uses the words "private cloud" is designed to appeal to an organization that needs or wants more control over their data than they can get by using a third-party hosted service." Basically, they opine that the term has marketing value only. Where does this place IT practitioners? Reading between the lines, they encourage us to ignore the usage of the term.
What Does it Mean, If Anything?
The fact that there's no single perspective on private cloud might indicate that none of the definitions really warrant separating the private cloud concept from that of cloud computing as a whole. One reasonable perspective is that the definitions discussed above are simply differing infrastructural and organizational approaches to implementing service-oriented cloud computing. Those approaches do not warrant a whole new term and certainly not millions more in infrastructure expenditure. Trying to create a new concept of private clouds from any of a number of perspectives--architectural, infrastructural, organizational, governance, and business model--seems to introduce more confusion than clarification. After all, shouldn't all clouds, private or not, provide the benefits described above? Doesn't the concept of a private, company-owned cloud in some ways weaken the cloud value proposition? Who really benefits from this private cloud discussion: IT practitioners or vendors with products to sell?
ZapThink has had many positive things to say about cloud computing, and we do believe that as a business model, technological approach, and service-oriented domain it will have significant impact on the way companies procure, develop, deploy, and scale their applications. We're starting to see hundreds of companies that develop whole products and services without procuring a penny of internal IT hardware or software resources. This is the bonanza that is cloud computing.
The point of any new term should be to clarify and differentiate. If the term does neither, then it is part of the problem, not the solution. When vendors start promoting their products with new terms, ask yourself: does this change what you are doing now, or is this the beating of the bandwagon's marketing drum? The goal is not to buy more stuff; the goal is to provide the business increasing value from existing IT investments. This is the purpose and goal of enterprise architecture and the reason why IT exists in the first place.