# 3.5: Cloud Computing

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# Cloud Computing

Historically, for software to run on a computer, an individual copy of the software had to be installed on the computer, either from a disk or, more recently, after being downloaded from the Internet. The concept of “cloud” computing changes this, however.

To understand cloud computing, we first have to understand what the cloud is. “The cloud” refers to applications, services, and data storage on the Internet. These service providers rely on giant server farms and massive storage devices that are connected via Internet protocols. Cloud computing is the use of these services by individuals and organizations.

You probably already use cloud computing in some forms. For example, if you access your e-mail via your web browser, you are using a form of cloud computing. If you use Google Drive’s applications, you are using cloud computing. While these are free versions of cloud computing, there is big business in providing applications and data storage over the web. Salesforce (see above) is a good example of cloud computing – their entire suite of CRM applications are offered via the cloud. Cloud computing is not limited to web applications: it can also be used for services such as phone or video streaming.

• No software to install or upgrades to maintain.
• Can scale to a large number of users easily.
• New applications can be up and running very quickly.
• Services can be leased for a limited time on an as-needed basis.
• You are not limited by the available memory or disk space on your computer.

• Your information is stored on someone else’s computer – how safe is it?
• You must have Internet access to use it. If you do not have access, you’re out of luck.
• You are relying on a third-party to provide these services.

Cloud computing has the ability to really impact how organizations manage technology. For example, why is an IT department needed to purchase, configure, and manage personal computers and software when all that is really needed is an Internet connection?

## Using a Private Cloud

Many organizations are understandably nervous about giving up control of their data and some of their applications by using cloud computing. But they also see the value in reducing the need for installing software and adding disk storage to local computers. A solution to this problem lies in the concept of a private cloud. While there are various models of a private cloud, the basic idea is for the cloud service provider to section off web server space for a specific organization. The organization has full control over that server space while still gaining some of the benefits of cloud computing.

## Virtualization

One technology that is utilized extensively as part of cloud computing is “virtualization.” Virtualization is the process of using software to simulate a computer or some other device. For example, using virtualization, a single computer can perform the functions of several computers. Companies such as EMC provide virtualization software that allows cloud service providers to provision web servers to their clients quickly and efficiently. Organizations are also implementing virtualization in order to reduce the number of servers needed to provide the necessary services. For more detail on how virtualization works, see this informational page from VMWare.

3.5: Cloud Computing is shared under a CC BY-SA license and was authored, remixed, and/or curated by David T. Bourgeois.