CHAPTER 1: Network Fundamentals 6
massive changes in the later part of the twentieth century. By looking at
these changes, you will see the development of OSes, hardware, and innova-
tions that are still used today.
Early Telecommunications and Computers
Telecommunications got its start in 1870s in Brantford Ontario, when
Alexander Graham Bell developed the idea of a telephone. After the first
successful words were sent over the device on March 10, 1876, a revolu-
tion of communication began. Within decades of its conception, millions of
telephones were sold, with operators connecting people using manual circuit
switching. This method of calling the operator to have them connect you to
another party was routine until the mid-twentieth century, when mechanical
and electronic circuit switching became commonplace. These events would
have a massive impact on the innovation of computers, even though they
wouldn’t be invented until 60 years after Bell’s first successful phone call.
Although arguments could be made as to whether ancient devices (such
as the abacus) could be considered a type of computer, the first computer that
could be programmed was developed by a German engineer named Konrad
Zuse. In 1936, Zuse created the Z1, a mechanical calculator that was the
NOTES FROM THE FIELD…
Knowledgeable Network Users
The Internet is a vast network of interconnected com-
puters that your computer becomes a part of when-
ever it goes online. Because more people than ever
before use the Internet, this means that many people
are familiar with the basic concepts and features of
networking without even being aware of it. This is a
particular benefit in training the users of a network,
as many will be familiar with using e-mail, having user
accounts and passwords, and other technologies or
procedures. Unfortunately, a little knowledge can also

programming. Although the next version of his computer would use punch
cards to store programs, Zuse used movie film to store programming and
data on the Z3 due to a supply shortage of paper during World War II. Just as
his computers evolved, so did his programming skills. Zuse’s achievements
also extended to creating the first algorithmic programming language called
Plankalkül, which later was used to create the first computer chess game.
During this same time, John Atanasoff and Clifford Berry developed
what is acknowledged to be the first electronic-binary computer. Created at
the University of Iowa, the initial prototype acquired this team a grant that
allowed them to build their 700 pound final product, containing more than
300 vacuum tubes and approximately one mile of wire. Because the war
prevented them from completing a patent on their computer, the computer
was dismantled when the physics department needed storage space that was
being used by the machine. The distinction of being first initially went to
John Mauchly and J. Presper Eckert for their Electrical Numerical Integrator
And Calculator (ENIAC I) computer, until a 1973 patent infringement case
determined Atanasoff and Berry were the first.
The ENIAC I was developed with funding from the U.S. government and
based on the work of John Atanasoff. Starting work in 1943, the project took
two and a half years to design and build ENIAC I, at a cost of half a million
dollars. The ENIAC I was faster than previous computers, and used to per-
form calculations for designing a hydrogen bomb, wind-tunnel designs, and
a variety of scientific studies. It was used until 1955 when the 30-ton, 1,800
square foot computer was ultimately retired.
Another computer that was developed during this time was the MARK I
computer, developed by Howard Aiken and Grace Murray Hopper in 1944
in a project cosponsored by Harvard University and International Business
Machines (IBM). Dwarfing the ENIAC at a length of 55 feet and five tons
in weight, the MARK I was the first computer to perform long calculations.
Although it was retired in 1959, it made a lasting mark on the English lan-

was the first commercially available computer to use transistors, and the
fastest computer of its time. Such innovations firmly placed IBM as a leader
in computer technology.
The Space Age to the Information Age
Although IBM and the owners of UNIVAC were contending for clients to buy
their computers, or at least rent computer time, the former USSR launched
Sputnik in 1957. Sputnik was the first man-made satellite to be put into
orbit, which started a competition in space between the USSR and the United
States, and launched a number of events that made advances in computers.
Although author Arthur C. Clark had published an article in 1945 describing
man-made satellites in geosynchronous orbit being used to relay transmis-
sions, communication satellites didn’t appear until after Sputnik’s historic
orbit. In 1960, Bell Telephone Laboratories (AT&T) filed with the FCC to
obtain permission to launch a communications satellite, and over the next
five years, several communication satellites were orbiting overhead.
Obviously, the most notable result of Sputnik was the space race between
the U.S. and USSR, with the ultimate goal of reaching the moon. The U.S.
started the National Aeronautics and Space Administration (NASA), began
launching space missions, and achieved the first manned landing on the
moon in 1969. Using computers that employed only a few thousand lines of
What Is a Network? 9
code (as opposed to the 45 million lines of code used in Windows XP), the
onboard computer systems provided necessary functions and communicated
with other computers on earth. Communications between astronauts and
mission control on earth also marked the furthest distance of people com-
municating to date.
The cold war and space race also resulted in another important milestone
in computer systems and communication systems. As we discussed earlier,
the U.S. government started the Advanced Research Projects Agency, which
developed such important technologies as follows:

Pentium (32-bit processor) produced in 1993, and which ended 
the x86 naming scheme for their processors. After this, Intel chips
bore the Pentium name, inclusive to the Pentium 75 (in 1994),
Pentium 120, 133, and Pentium Pro 200 (in 1995), Pentium MMX
and Pentium II (in 1997), and Pentium III (in 1999). As you would
expect, each generation was faster than the last.
Just as processing changed in the 1970s, so did storage. In 1973, IBM
developed the first hard disk, and an 8” floppy drive, replacing the need to
store data and programs solely on magnetic tapes. This massive floppy was
quickly replaced by the 5.25” floppy in 1976, which was later succeeded by
the 3.5” floppy disk that was developed by Sony in 1980. These methods of
storing data became commonplace until 1989 when the first CD-ROM was
developed, and again changed in 1997 with the introduction of DVDs.
With the advances in technology, it was only a matter of time before
someone developed a home computer. Prior to the mid-1970s, computers
were still too large and expensive to be used by anyone but large corporations
and governments. With the invention of the microprocessor, a company
called Micro Instrumentation and Telemetry Systems (MITS) developed the
Altair 8800 using the Intel 8080 processor. Although it included an 8” floppy
drive, it didn’t have a keyboard, monitor, or other peripherals that we’re
accustomed to today. Programs and data entry were entered using toggle
switches at the front of the machine. Although it couldn’t be compared to
personal computers of today, it did attain the distinction of being the first.
The Altair also provides a point of origin for Microsoft, as Bill Gates
and Paul Allen developed a version of the BASIC programming language for
Altair that was based on a public domain version created in 1964. Microsoft
went on to create an OS that required users to type in commands called
PC-DOS for the first IBM computer named The Acorn in 1981, but main-
tained ownership of the software. This allowed them to market their OS to
other computer manufacturers and build their software empire. Microsoft

processing power and were only used to access mainframe computers. It
connected computers together using cabling and network adapters, allowing
them to communicate with one another over these physical connections. If
Ethernet sounds like many networks in use today, you’d be correct; Ethernet
is an industry standard.
After Ethernet was developed, OSes that were specifically designed for
networking weren’t far behind. In 1979, Novell Data Systems was founded
with a focus on developing computer hardware and OSes. In 1983, however,
Novell changed focus and developed NetWare, becoming an industry leader
in network OSes. Unlike other OSes that resided on a computer and could
be used as either a standalone machine or a network workstation, NetWare
has two components. The NetWare OS is a full OS and resides on a server,
which processes requests from a network user’s client machine. The com-
puter that the network user is working on can run any number of different
OSes (such as Windows 9x, NT, etc), but has client software installed on it
that connects to the NetWare server. When a request is made to access a
file or print to a NetWare server, the client software redirects the request to
the server. Because of its popularity as a network OS, it was widely used on
corporate and government networks.
CHAPTER 1: Network Fundamentals 12
The Information Age Appears
In the 1980s, computers became more commonplace in homes and
businesses. Prices had dropped to the point that it was now affordable to
have a computer in the home, and powerful enough to be worth having a
286 or 386 computer. Although many people found computers useful, they
quickly outgrew the desire to have a standalone machine and wanted to be
networked to others.
The 1980s and 1990s saw growing popularity in Bulletin Board Sys-
tems (BBSs), where one computer could use a modem and telephone line to
directly dial another computer. Computers with BBS software provided the

the Internet. In 1993, other Internet service providers (ISPs) appeared that
What Is a Network? 13
provided this service, increasing the number of people using the Internet
steadily. Although initially used as a repository of programs, research, and
other resources, this opened the Internet up to commercial use, which
evolved it into the entity we know today.
Modern Networking Technologies
Since the year 2000, when Y2K was the biggest rage and the e-mail virus
Melissa was first introduced, there have been countless developments in net-
working. Although there have been many new technologies developed, one
thing remains the same – the fundamentals of networking have not changed.
We still use models to explain, design, administer, and troubleshoot net-
working today and because of those standards more and more proprietary
development (closed source) software, systems, and services are starting to
disappear.
Open source technologies are starting to take hold in the market as
support for them grows within the communities that develop them. Some
newer technologies that we will cover in this book are multiprotocol label
HEAD OF THE CLASS…
Virtualization
The term virtualization is very broad. In its simplest
definition, it’s the term used to explain how hardware
resources and OSes are managed using virtualiza-
tion software such as VMware ESX Server, Windows
Hyper-V, and Citrix Xen to name a few of the most com-
monly used systems.
There are also many types of virtualization – desktop
virtualization, storage virtualization, application virtual-
ization, and server virtualization … the list goes on. The
underlying theory for all is that the OS is abstracted

CHAPTER 1: Network Fundamentals 14
switching (MPLS), virtualization, and cloud computing among many others.
They are paving the way for even newer breakthroughs to take place over the
next year. Some jokingly say that the LAN is dead – could it be true?
Mobile networking is also becoming increasingly important because of
this. As more and more games, videos, and songs are distributed over mobile
devices, the demand to supply faster, more robust ways to support them over
the network will take place. As we approach 2010, it’s interesting to look
back on the last decade of networking … how it has evolved and where we
will wind up next.
LOGICAL NETWORKING TOPOLOGIES
Because networks vary from one another depending upon a range of factors,
it should come as no surprise that there are different network models that
can be chosen. The network model you choose will affect a network infra-
structure’s design, and how it is administered. Depending on the model or
models used, it can have an impact on the location of computers, how users
access resources, and the number of computers and types of OSes required.
Some of the models and topologies available to choose from are as follows:
Centralized
Decentralized (Distributed)
Peer-to-Peer
Client/Server
Virtual Private Network (VPN)
Virtual Local Area Network (VLAN)
Because it’s arguable that there is little need for a network without the
use or sharing of resources on it, then we would have to say that all resources
would either have to be centralized, decentralized, or multiple networks con-
figured and accessible to facilitate both models simultaneously.
Note
We cover new technologies for completeness, although not all new (or bleeding edge)

If the user sent a print job to this plotter, someone from the IT staff would
need to enter the secure room to get their printout. In addition, there would
also be the need to replace paper and toners used in the device. In a central-
ized model, administration of the resources is also centralized.
Despite the previous scenario, in some ways managing resources can be
easier with this model. By keeping these resources in one area, a network
administrator can easily change backup tapes, replace hard disks, or fix other
issues as required. Imagine the issues of having servers in offices throughout
a city or region, and having to visit each of them whenever a tape needed to
be replaced after running a tape backup. By keeping resources centralized,
less work is needed for administration of them.
Depending on the requirements of an organization, the centralized net-
work model can also mean that fewer servers or other devices are needed.
Rather than each building having their own server on the premises, users