Page 162 - Using MIS

130 Chapter 4 Hardware, Software, and Mobile Systems

Figure 4-14
Virtual Machine Example
Source: Microsoft Corporation

to either of those virtual machines, and they will appear as normal servers. Figure 4-14 shows
how virtual machine VM3 appears to a user of that server. Notice that a user of VM3 is running
a browser that is accessing SharePoint. In fact, this virtual machine was used to generate many
of the SharePoint figures in Chapter 2. Server virtualization plays a key role for cloud vendors, as
you’ll learn in Chapter 6.
PC virtualization is interesting as well as quite useful, as you will learn in Chapter 6.
Desktop virtualization, on the other hand, has the potential to be revolutionary. With desktop
virtualization, a server hosts many versions of desktop operating systems. Each of those desk-
tops has a complete user environment and appears to the user to be just another PC. However,
the desktop can be accessed from any computer to which the user has access. Thus, you could
be at an airport and go to a terminal computer and access your virtualized desktop. To you, it
appears as if that airport computer is your own personal computer. Using a virtual desktop also
means that you wouldn’t have to worry about losing a corporate laptop or confidential internal
data. Meanwhile, many other users could have accessed the computer in the airport, and each
thought he or she had his or her personal computer. IBM offers PC virtualization for as low as
$12 a month per PC.
Desktop virtualization is in its infancy, but it might have major impact during the early
years of your career.

Own Versus License

When you buy a computer program, you are not actually buying that program. Instead, you
are buying a license to use that program. For example, when you buy a Mac OS license, Apple
is selling you the right to use Mac OS. Apple continues to own the Mac OS program. Large or-
ganizations do not buy a license for each computer user. Instead, they negotiate a site license,
which is a flat fee that authorizes the company to install the product (operating system or appli-
cation) on all of that company’s computers or on all of the computers at a specific site.
In the case of Linux, no company can sell you a license to use it. It is owned by the open
source community, which states that Linux has no license fee (with certain reasonable restric-
tions). Large companies such as IBM and smaller companies such as RedHat can make money
by supporting Linux, but no company makes money selling Linux licenses.