Technically Speaking: What Is Cloud Computing?

A couple of years ago in 2007, Google, IBM, and others set out on a large-scale cloud computing project. By mid-2008, Gartner, from Gartner.com, saw an opportunity for cloud computing to “shape the relationship among consumers of IT services, those who use IT services, and those who sell them,” and observed that “organizations are switching from company-owned hardware and software assets to per-use, service-based models” so that the “projected shift to cloud computing … will result in dramatic growth in IT products in some areas and in significant reductions in other areas.”

IBM states-

“A new era is here. Information technology is changing rapidly, and now forms an invisible layer that increasingly touches every aspect of our lives. Power grids, traffic control, healthcare, water supplies, food, and energy, along with most of the world’s financial transactions, all now depend on information technology.

An emerging computer model–cloud computing–addresses the explosive growth of Internet-connected devices, and complements the increasing presence of technology in today’s world. Cloud computing is massively scalable, provides a superior user experience, and is characterized by new, Internet-driven economics.”

Cloud computing is Internet-based development and use of computer technology. In concept, it is a shift whereby details are abstracted from the users who no longer need knowledge of, expertise in, or control over the technology infrastructure “in the cloud” that supports them. It typically involves the provision of dynamically scalable and often virtualized resources as a service over the Internet.

The term cloud is used as a metaphor for the Internet, and is an abstraction of the underlying infrastructure it conceals. Typical clouds deliver common business applications online which are accessed from a web browser, while the software and data are stored on the servers.

These applications are generally divided into a handful of categories: Software as a Service (SaaS), Utility Computing, Web Services, Platform as a Service (PaaS), Managed Service Providers (MSP), Service Commerce, and Internet Integration.

Software as a Service

SaaS delivers a single application through the browser to thousands of customers using a multitenant architecture. On the user end, it means no upfront costs for servers or software licensing; on the provider side, with only a single app to maintain, costs are low compared to conventional hosting.

SaaS Examples:

• Oracle CRM On Demand

• Salesforce.com

• Google Apps

• Zoho Office

Utility Computing

Utility Computing delivers storage and virtual servers that IT can access on demand. Generally used for supplemental, non-mission-critical needs, it is possible that this may one day replace areas in the data center.

Web Services

Web Services offer APIs that enable developers to exploit functionality over the Internet, rather than delivering full-blown applications.

Web Services Examples:

• Google Maps

• U.S. Postal Service

• Conventional credit card processing services

Platform as a Service

PaaS delivers development environments as a service. One can build their own applications that run on the cloud’s infrastructure and then are delivered to users via the Internet from the cloud’s servers. However, these services are constrained by the cloud’s design and capabilities, so there isn’t complete freedom, but there is predictability and pre-integration.

PaaS Examples:

• Salesforce.com’s Force.com

• Google App Engine

• Yahoo Pipes

Managed Service Providers

MSP are applications exposed to IT admin rather than to end-users, such as anti-virus for email or an application-monitoring service.

Service Commerce

Service Commerce offers a service hub that users interact with, common in trading environments such as expense management systems that allow users to order travel or secretarial services from a common platform that then coordinates the service delivery and pricing within the specifications set by the user.

Internet Integration

Cloud computing users do not generally own the physical infrastructure, instead renting usage from a third-party provider. Customers use resources and pay only for resources that they use. Sharing “perishable and intangible” computing power among multiple users can improve utilization rates, as servers are not unnecessarily left idle, which can reduce costs significantly while increasing the speed of application development. Other benefits of this time sharing-style approach are low barriers to entry, shared infrastructure and costs, low management overhead, and immediate access to a broad range of applications.

The majority of cloud computing infrastructure, as of 2009, consists of reliable services delivered through data centers and built on servers with different levels of virtualization technologies. The services are accessible anywhere that provides access to networking infrastructure. Open standards are critical to the growth of cloud computing, and open source software has provided the foundation for many cloud computing implementations.