ALSO SEE: Ten Cloud Computing Leaders
Cloud computingis a method of provisioning computing resources, including both hardware and software, that relies on sharing those resources rather than using local servers or personal devices to handle applications.
In theory, cloud computing is a way for IT departmentsto increase capacity or add capabilities on the fly, without having to invest in new infrastructure, train new personnel or license new software.
In the cloud computing model, workers log into a Web-based service that hosts all the programs the users need for their jobs, from e-mail to word processing to complex Business Intelligence software. The service, and the hardware it runs on, is deployed, maintained and upgraded by another company, which generally offers service-level agreements(SLAs) to guarantee the service.
Examples of cloud computing include using Google App Engine to run your company's e-mail services, contracting with Amazon Web Services to host your infrastructure, or contracting with Salesforce.comto provision your company's customer relationship management (CRM) software.
The number of cloud computing vendors is growing rapidly, with a continual fresh crop of cloud computing start-ups. Indeed, because of the potential power and influence, the fierce struggle to dominate the cloud computing marketis prompting titanic investments.
Cloud Computing Definitions
Cloud Services, contrast with Cloud Computing
Cloud Computing, contrast with Cloud Services
Cloud Computing vs. Utility Computing vs. SaaS
Cloud Computing Benefits
Cloud Computing Concerns
Cloud Computing's Five Myths
Cloud Computing: News and Additional Resources
The definition of cloud computing remains somewhat fuzzy, as it is often used to describe an array of related concepts. More than a few people are uncertain as to what separates cloud computing related concepts such as utility computing, software-as-a-service (SaaS) and virtualization.
The vagary led Larry Ellison, Oracle's chief executive officer, to famously say of cloud confusion, "The interesting thing about cloud computing is that we've redefined cloud computing to include everything that we already do. I can't think of anything that isn't cloud computing with all of these announcements. The computer industry is the only industry that is more fashion-driven than women's fashion. Maybe I'm an idiot, but I have no idea what anyone is talking about. What is it? It's complete gibberish. It's insane. When is this idiocy going to stop?
"We'll make cloud computing announcements. I'm not going to fight this thing. But I don't understand what we would do differently in light of cloud."
That hasn't stopped analysts at research firm IDC from attempting to establish a more concrete definition. For those who continue to seek more useful terminology, IDC distinguishes between Cloud Servicesand Cloud Computing.
"When most people talk about "cloud computing," they usually refer to online delivery and consumption models for business and consumer services," said IDC's Frank Gens. "These services include IT services—like software-as-a-service (SaaS) and storage or server capacity as a service—but also many, many "non-IT" business and consumer services.
"Indeed, the vast majority of these online services are not, in the mind of the user, IT or "computing" at all—they are about shopping, banking, selling, collaborating, communicating, being entertained, etc. In other words, most people using these services are not "computing," they are living! These customers are not explicitly buying "cloud computing," but "cloud services" that are enabled by cloud computing environments; cloud computing is hidden underneath the business or consumer service."
So IDC's definitional framework is as follows:
In other words cloud computing is the IT environment that encompasses the stack of IT and network products that enables the development, delivery and consumption of cloud services.
According to IDC, there are eight key attributes that define cloud services, as follows:
Meanwhile, cloud computing is the IT foundation for cloud services. A partial list of cloud computing attributes compiled by IDC include the following:
But IDC's definitions are not universally shared. According to 3Tera Chairman Barry X Lynn, cloud computingenables users and developers to utilize services without knowledge of, expertise with, nor control over the technology infrastructure that supports them. Meanwhile, utility computing provides on-demand infrastructure with the ability to control, scale and configure that infrastructure.
SaaS, according to Lynn, is a software-enabled service that is offered on the Web on a month-to-month subscription or a pay-per-use basis, rather than having to purchase or license the software.
Under IDC's rubric, utility computing falls under the umbrella of the cloud computing definition, while SaaS falls under the umbrella of cloud services.
So what potential benefits does cloud computing offer? According to Forrester analyst Ted Schadler, there are three key benefits of cloud computing:
• First, cloud computing promises speed. IT departments don't have to go through the lengthy process of building IT infrastructure and deploying software to multitudes of computers when using cloud services. Instead, they subscribe to services and receive them.
• Second, the cloud computing provider is responsible for maintaining and upgrading the infrastructure, meaning that the customer's IT staff can focus on more important core business processes.
• Third, firms only have to pay for the resources they use. Instead of buying hardware, software and consultants to set up and run applications, businesses can pay a cloud-based provider by the user by the month.
Disaster recoveryis another added benefit. Cloud providers are offsite, maintain the servers in their own data centers, fix any problems, manage disaster recovery planning and continually upgrade the software.
Other benefits of cloud computinginclude:
There are a number of issues surrounding cloud computingas well, including security, privacy, compliance and vendor lock-in.
Cloud computing security is an oft-cited reason for wariness toward cloud services. Skeptics argue that once your data exists out in the cloud, you are hard-pressed to ensure no one else has access to it. This issue may be causing more than a few firms to delay adoption of cloud services.
Burton Group analyst Eric Maiwald said firms considering cloud services should resolve these issues with providers before jumping in: how data is encrypted and stored, how e-discovery can be done if need be, what controls there are and whether the cloud provider has passed a SAS-70 audit.
According to a report released by the Cloud Security Alliance in March, the top threats to cloud computinginclude the following:
San Francisco's Golden Gate University moved to a largely cloud-based infrastructure several years ago. According to Anthony Hill, the CIO of Golden Gate University who oversaw the move to cloud, not all is as it seems when it comes to both the benefits and problems of cloud computing.
Hill said that while security is often the first concerned mentioned when it comes to cloud computing, he doesn't see it as a big concern. He told InformationWeek's Frederic Paul that he's more comfortable with his data in an Oracle data center than he is with it in his own data center. He noted that no midmarket organization could bring to bear the level of security and redundancy on its own that Oracle offers.
On the other hand, Hill said that cloud-computing champions often trumpet the ability to avoid capital expenditures (CapEx) in favor of operating expenditures (OpEx). He noted that in the real world it is sometimes advantageous to bury IT costs in the capital budget and keep it off the P & L for a few years.
Another benefit of cloud computing is the ability to offload management risk. The vendor becomes responsible for reliability, availability and so forth. However, Hill noted that companies should remember that they are exchanging management risk for vendor risk. Organizations are still vulnerable to business disruptions if the vendor experiences problems, or, worse, goes out of business.
Some cloud-computing advocates also suggest that the model provides a great deal of agility. But Hill said switching vendors is not a trivial task. In fact, Richard Stallman, outspoken founder of the Free Software Foundation, has called cloud computing a "trap" that forces people into locked, proprietary systems.
Finally, Hill said it is a myth that "tight" SLAs, which measure breach of contract by specific metrics, are the key to a successful relationship with a cloud-computing vendor. Instead, Hill suggested cloud-computing customers negotiate SLAs that allow for termination based on lack of customer satisfaction.
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