Shedding Light on Cloud Computing

Introduction

Cloud is a collective term for a large number of developments and possibilities. It is not an invention, but more of a practical innovation, combining several earlier inventions into something new and compelling. Much like the iPod is comprised of several existing concepts and technologies (the Walkman, MP3 compression and a portable hard disk), cloud computing merges several already available technologies: high bandwidth networks, virtualization, Web 2.0 interactivity, time sharing, and browser interfaces.

To understand why there is so much excitement around cloud computing today while the concept is not truly new, it is important to understand that cloud services need very fast and broad networks to work smoothly. Twenty years ago no-one would have conceived of cloud computing because the networks in those days were simply too slow. And even ten years ago no one considered it because every Enter or mouse click would have cost $10 in communication costs. But with the global network innovations made over the past few years, these networks are finally ready for primetime, i.e. cloud computing.

In this primer, we will first look at the various definitions of cloud computing and at some of the reasons why organizations would want to implement cloud computing, such as cost-savings, increased speed and flexibility and higher performance.

We will also look at the risks of cloud computing. Risk is consistently cited by CIOs and CFOs as the largest obstacle of cloud computing for their organizations. We will consider the risks in areas such as availability, privacy and regulatory compliance.

Next we delve more deeply into the various types of cloud computing. We will discuss the cloud infrastructure also known as Infrastructure as a Service, and also at the application cloud, also known as Software and Platform as a Service.

When we talk about cloud computing in an infrastructure context, virtualization plays an important role, so we will explore this concept in more depth. In the last part we will explore the impact of cloud computing on organizations, looking forward to what the future holds, along with its impact on IT management.

Cloud Computing Defined

The term cloud computing was first used in an academic context by Prof. Kenneth K Chellapa, who described it in 1997 at the Informs Conference in Dallas [1] as a computing paradigm where the boundaries of computing will be determined by economic rationale rather than technical limits. This description is clearly broader and less technical than many of the definitions in circulation today. Current definitions, as the one below from Wikipedia all assume some use of the internet (or at least some internet technology) to classify something as cloud computing.

Cloud Computing

From Wikipedia, the free encyclopedia

Cloud Computing is a popular phrase that is shorthand for applications that were developed to be  that run on the Internet (or Cloud). In the Cloud Computing paradigm,  that is traditionally installed on personal computers is shifted or extended to be accessible via the Internet. These Cloud applications or Cloud apps utilize massive  and powerful servers that host  and . They can be accessed by anyone with a suitable Internet connection and a standard .

Forrester, Gartner and other analysts all have their own definition, many of which are still evolving. A very pragmatic definition is used by Consulting firm Accenture: the dynamic provisioning of IT capabilities (hardware, software, or services) from third parties over a network [12]

The currently most accepted or official definition of cloud computing is provided by the North American National Institute for Standard and Technology (NIST), a shortened version is listed below.

The NIST Definition of Cloud Computing (version 15, shortened)

Cloud Computing is a model for enabling 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