Management Information Systems, 13TH ED.
MANAGING THE DIGITAL FIRM
Kenneth C. Laudon ● Jane P. Laudon
continued
Learning Track 5: The Evolution of IT Infrastructure
e IT infrastructure in organizations today is an outgrowth of over 50 years of evolution in
computing platforms. ere have been five stages in this evolution, each representing a dierent
configuration of computing power and infrastructure elements (see Figure 5.2). e five eras are
General-Purpose Mainframe and Minicomputer Era:
(1959 to Present)
e introduction of the IBM 1401 and 7090 transistorized machines in 1959 marked the begin–
ning of widespread commercial use of mainframe computers. In 1965, the mainframe computer
truly came into its own with the introduction of the IBM 360 series. e 360 was the first commer–
cial computer with a powerful operating system that could provide time sharing, multitasking, and
virtual memory in more advanced models. IBM has dominated mainframe computing from this
Chapter 5: IT Infrastructure and Emerging Technologies
Chapter 5 Learning Track 5 2
continued
FIGURE 5.2 Eras in IT Infrastructure Evolution
Illustrated here are
the typical computing
Chapter 5 Learning Track 5 3
continued
Personal Computer Era: (1981 to Present)
Although the first truly personal computers (PCs) appeared in the 1970s (the Xerox Alto, the MITS
Altair 8800, and the Apple I and II, to name a few), these machines had only limited distribution to
computer enthusiasts. e appearance of the IBM PC in 1981 is usually considered the beginning
of the PC era because this machine was the first to be widely adopted by American businesses. At
first using the DOS operating system, a text–based command language, and later the Microsoft
Windows operating system, the Wintel PC computer (Windows operating system software on a
computer with an Intel microprocessor) became the standard desktop personal computer. In 2012,
Client/Server Era (1983 to Present)
In client/server computing, desktop or laptop computers called clients are networked to power–
ful server computers that provide the client computers with a variety of services and capabili-
ties. Computer processing work is split between these two types of machines. e client is the
user point of entry, whereas the server typically processes and stores shared data, serves up Web
pages, or manages network activities. e term “server” refers to both the software application
and the physical computer on which the network software runs. e server could be a mainframe,
Chapter 5 Learning Track 5 4
continued
FIGURE 5.3 A Multitiered Client/Server Network (N-Tier)
In a multitiered client/server network, client requests for service are handled by different levels of
servers.
For instance, at the first level, a Web server will serve a Web page to a client in response to a
request for service. Web server software is responsible for locating and managing stored Web
pages. If the client requests access to a corporate system (a product list or price information,
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 communications environment after 1995, business firms began
Chapter 5 Learning Track 5 5
e resulting IT infrastructure links dierent pieces of computer hardware and smaller networks
into an enterprise-wide network so that information can ow freely across the organization and
Cloud and Mobile Computing Era (2000 to Present)
e 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, appli-
cations, and services) over the Internet. ese “clouds” of computing resources can be accessed
on an as-needed basis from any connected device and location. Currently, cloud computing is the