Page 201 -

200 Part Two Information Technology Infrastructure

for locating and managing stored Web pages. If the client requests access to a
corporate system (a product list or price information, for instance), the request
is passed along to an application server. Application server software han-
dles all application operations between a user and an organization’s back-end
business systems. The application server may reside on the same computer
as the Web server or on its own dedicated computer. Chapters 6 and 7 provide
more detail on other pieces of software that are used in multitiered client/
server architectures for e-commerce and e-business.
Client/server computing enables businesses to distribute computing work
across a series of smaller, inexpensive machines that cost much less than cen-
tralized mainframe systems. The result is an explosion in computing power and
applications throughout the firm.
Novell NetWare was the leading technology for client/server networking at
the beginning of the client/server era. Today, Microsoft is the market leader
with its Windows operating systems (Windows Server, Windows 8, Windows 7,
and Windows Vista).

Enterprise Computing Era (1992 to Present)
In the early 1990s, firms turned to networking standards and software tools that
could integrate disparate networks and applications throughout the firm into an
enterprise-wide infrastructure. As the Internet developed into a trusted com-
munications environment after 1995, business firms began seriously using the
Transmission Control Protocol/Internet Protocol (TCP/IP) networking standard to
tie their disparate networks together. We discuss TCP/IP in detail in Chapter 7.
The resulting IT infrastructure links different pieces of computer hardware
and smaller networks into an enterprise-wide network so that informa-
tion can flow freely across the organization and between the firm and other
organizations. It can link different types of computer hardware, including
mainframes, servers, PCs, and mobile devices, and it includes public infrastruc-
tures such as the telephone system, the Internet, and public network services.
The enterprise infrastructure also requires software to link disparate applica-
tions and enable data to flow freely among different parts of the business, such
as enterprise applications (see Chapters 2 and 9) and Web services (discussed
in Section 5.4).

Cloud and Mobile Computing Era (2000 to Present)
The growing bandwidth power of the Internet has pushed the client/server
model one step further, towards what is called the “Cloud Computing Model.”
Cloud computing refers to a model of computing that provides access to a
shared pool of computing resources (computers, storage, applications, and
services) over a network, often the Internet. These “clouds” of computing
resources can be accessed on an as-needed basis from any connected device
and location. Currently, cloud computing is the fastest growing form of com-
puting, with companies spending about $109 billion on public cloud services in
2012, and an estimated $207 billion by the end of 2016 (Gartner, 2012).
Thousands or even hundreds of thousands computers are located in cloud data
centers, where they can be accessed by desktop computers, laptop computers,
tablets, entertainment centers, smartphones, and other client machines linked to
the Internet, with both personal and corporate computing increasingly moving
to mobile platforms. IBM, HP, Dell, and Amazon operate huge, scalable cloud
computing centers that provide computing power, data storage, and high-speed
Internet connections to firms that want to maintain their IT infrastructures

MIS_13_Ch_05_Global.indd 200 1/17/2013 3:04:21 PM