Cloud computing is not really a technology by itself, but an approach to building IT services. This approach harnesses several converging factors in the IT world, including the rapidly increasing horsepower of servers and virtualisation technologies that unleash power by combining many servers into large computing pools and dividing single servers into multiple virtual machines that can be spun up and powered down, at will.
Led by companies such as Amazon, vendors are building massively scalable server farms to offer compute power, storage, business software and application building platforms over the Internet, using self-service interfaces that let customers acquire resources at any time they want and get rid of them the instant they are no longer needed. Private clouds, deployed by enterprises for their own users, are built along the same principles, but done so completely within the firewall.
Amazon CTO Werner Vogels, delivering a speech at Sys-Con's recent Cloud Computing Conference and Expo in the US, showed a slide featuring an early 1900s beer brewery that contained its own power generators. "They had to be experts in electricity to brew beer. Something is off there," he said. "These guys couldn't wait to dump their own generators and start to use electricity from other companies."
Just as electricity became a shared service, or utility, so too will computing power, Vogels and other commentators say. If you are the founder of a start-up that is building an application for Facebook, you have to prepare for the possibility of becoming immensely popular overnight, Vogels says. But you might also fail. That's why you need on-demand access to the power of 5,000 servers at any time, without having to spend the money upfront. Or if you run a seasonal business, you may need huge amounts of computing power one month out of the year, but very little during the remaining 11 months.
"There is a shift from infrastructure being a capital expense to a variable cost," Vogels said.
Grid computing’s cousin
Cloud computing borrows concepts from grid computing, namely the ability to harness large collections of independent computing resources to perform large tasks; and from utility computing, namely the metered consumption of IT services, according to IBM. But perhaps the real impetus for cloud computing are failings within the current IT infrastructure, the company believes.
Seven out of ten IT dollars are spent on maintaining current systems, and perhaps 85 per cent of capacity in distributed computing environments sits idle at any given time, IBM said. Storage requirements are escalating too quickly for many data centers to keep up.
The basic message from vendors: Cloud computing, while still in its infancy, is the solution to these problems.
Recently, there has been the release of the Open Cloud Manifesto, a document urging vendors to agree on basic principles related to cloud computing and the interoperability of competing cloud services. The manifesto drew criticism from Microsoft, but has a long list of supporters including major industry players such as AMD, IBM, Rackspace, Sun and VMware.
Cloud computing start-up Enomaly, one of the companies responsible for bringing the manifesto to the public, advocates the creation of an industry association focused on marketing a cohesive picture of what is cloud computing.
Market opportunity
Still, many questions remain to be answered about cloud computing. Customers want data security, performance, availability, and service-level agreements guaranteeing minimum standards for all three.
While companies such as Amazon and Rackspace offer computing power over the Web, and the Salesforce.coms of the world deliver software-as-a-service, a whole crop of third-party vendors, who layer services over the cloud, is starting to emerge.
Security and customers' ability to control their own resources are among the top concerns, according to Cohesive FT, a vendor whose technology helps customers shift workloads to virtualised platforms and external cloud services with a standard interface. Cloud computing may be an improvement over existing systems in many ways, but it's definitely not a panacea for bad design, the vendor believes.
Cloud vendors will be judged on five points: security, scalability, availability, performance and cost-effectiveness. While there are shortcomings today, huge advancements are predicted in the next few years.
