Continuing the journey to find better definitions for cloud computing concept, model, and basically classifications, let’s look this time at CIO.com pages dedicated to Cloud Computing Definitions and Solutions. Admitting any theoretical definition of cloud computing could be controversial, CIO is proposing concise definition of consulting firm Accenture:
“Cloud computing is the dynamic provisioning of IT capabilities (hardware, software, or services) from third parties over a network.”
We have to recognize this is a very concise definition… Starting from here, CIO is developing the more deeply description of cloud computing as model, not as technology.
According CIO, “Cloud computing is computing model, not a technology. In this model of computing, all the servers, networks, applications and other elements related to data centers are made available to IT and end users via the Internet, in a way that allows IT to buy only the type and amount of computing services that they need. The cloud model differs from traditional outsourcers in that customers don’t hand over their own IT resources to be managed.”
From CIO perspective the differences between virtualization and cloud are related to different levels of abstraction used. Admitting “virtualization most often means server virtualization — in which one physical server acts as host to several virtual servers, each of which runs on a layer of software called a hypervisor whose job it is to parcel out storage, memory and other computing resources,” cloud computing is taking this abstraction one further step. “Rather than making one server appears to be several, it makes an entire data-center worth of servers, networking devices, systems management, security, storage and other infrastructure, look like a single computer, or even a single screen.”
Finally, here is CIO description of the three basic types of cloud computing:
• Infrastructure as a Service — provides grids or clusters or virtualized servers, networks, storage and systems software designed to augment or replace the functions of an entire data center. The highest-profile example is Amazon’s Elastic Compute Cloud [EC2] and Simple Storage Service, but IBM and other traditional IT vendors are also offering services.
• Platform as a Service — Provides virtualized servers on which users can run existing applications or develop new ones without having to worry about maintaining the operating systems, server hardware, load balancing or computing capacity. Highest-profile examples include Microsoft’s Azure and Salesforce’s Force.com.
• Software as a Service — The most widely known and widely used form of cloud computing, SaaS provides all the functions of a sophisticated traditional application, but through a Web browser, not a locally-installed application. SaaS eliminates worries about app servers, storage, application development and related, common concerns of IT. Highest-profile examples are Salesforce.com, Google’s Gmail and Apps, instant messaging from AOL, Yahoo and Google, and VoIP from Vonage and Skype.
Photo Source: comparethecloud.net