Because of a response I received to my last post about the cloud enhancing customer experience I realized a definition of “the cloud” may be helpful. The idea of the cloud is rather nebulous. On top of the confusion you have distinct kinds of clouds like private clouds. But, thanks to my friend, Steve Greenberg, I learned that all clouds have similar characteristics.
The National Institute of Standards and Technology (NIST) actually has created the recognized definition of the cloud. Here it is:
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Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. This cloud model is composed of five essential characteristics, three service models, and four deployment models.
Essential Characteristics:
On-demand self-service. A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider.
Broad network access. Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, tablets, laptops, and workstations).
Resource pooling. The provider’s computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. There is a sense of location independence in that the customer generally has no control or knowledge over the exact location of the provided resources but may be able to specify location at a higher level of abstraction (e.g., country, state, or datacenter). Examples of resources include storage, processing, memory, and network bandwidth.
Rapid elasticity. Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be appropriated in any quantity at any time.
Measured service. Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.
Service Models:
Software as a Service (SaaS). The capability provided to the consumer is to use the provider’s applications running on a cloud infrastructure. The applications are accessible from various client devices through either a thin client interface, such as a web browser (e.g., web-based email), or a program interface. The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user- specific application configuration settings.
Platform as a Service (PaaS). The capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages, libraries, services, and tools supported by the provider.3 The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and possibly configuration settings for the application-hosting environment.
Infrastructure as a Service (IaaS). The capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, and deployed applications; and possibly limited control of select networking components (e.g., host firewalls).
Deployment Models:
Private cloud. The cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple consumers (e.g., business units). It may be owned, managed, and operated by the organization, a third party, or some combination of them, and it may exist on or off premises.
Community cloud. The cloud infrastructure is provisioned for exclusive use by a specific community of consumers from organizations that have shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be owned, managed, and operated by one or more of the organizations in the community, a third party, or some combination of them, and it may exist on or off premises.
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Ok. If my kids are reading this their eyes have glazed over. But the characteristics of the cloud are vital to our understanding of what it should do for us. The value of “the cloud” is that is allows us to pool our services from multiple locations reducing our dependence on geographic staffing and increasing our ability to collaborate. It should be metered… At some level it should allow us to pay for what we use and eliminate waste. It should be easily scalable… Not requiring a lot of heavy lifting or effort to expand its use as our organizations grow. And it should be available to us on demand over any network and any device… we use it when we want it, wherever we want it on the device we want to use.
The bottom line is that these five characteristics are major economical drivers that make business more efficient and the customer experience of our organizations more valuable. Two great examples of companies that are providing true cloud services are Citrix and Salesforce.com. Both meet these characteristics although they provide “the cloud” in different ways.
Salesforce.com, for example, has proven it’s ability to service from the small and medium size organizations all the way to the largest in the Enterprise space. Because Salesforce.com doesn’t require heavy equipment expenses and large upfront investments they’ve proven to be a versatile provider. But, Salesforce.com is also extremely accessible and very malleable which is key to ensuring excellent customer experiences.
I hope this definition helps. Let me know how this definition fits against your own. What you would add or delete?
Virtual Ideas 
I just received some great feedback from Aaron McCoy at Sprint Wireless about this article. I had to share it. He wrote: ” The easiest way to understand the cloud is to think of it as a utility, like electricity. When you plug a device into a wall outlet, electricity flows. You didn’t generate the electricity yourself. In fact, you probably have no idea where the electricity was generated. It’s just there when you want it. All you care about is that your device works.Cloud computing works on the same principle. Through an internet connection (the equivalent of an electrical outlet), you can access whatever applications, files, or data you have opted to store in the cloud–anytime, anywhere, from any device. How it gets to you and where it’s stored are not your concern (well, for most people they’re not).The potential benefits of this approach are enormous. To stick with the electricity analogy, if your IT department is still pre-cloud, it’s running the equivalent of its own generator. And with that comes a load of responsibility: Generators break, they run out of fuel, they need to be serviced, and–if demand for power increases–new ones need to be bought and brought online. “
Great post and puts some very simple definitions behind what is actually quite complicated