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Chapter 1
The Evolution of Cloud
Computing
1.1 Chapter Overview
It is important to understand the evolution of computing in order to get an
appreciation of how we got into the cloud environment. Looking at the evo-
lution of the computing hardware itself, from the first generation to the cur-
rent (fourth) generation of computers, shows how we got from there to
here. The hardware, however, was only part of the evolutionary process. As
hardware evolved, so did software. As networking evolved, so did the rules
for how computers communicate. The development of such rules, or proto-
cols, also helped drive the evolution of Internet software.
Establishing a common protocol for the Internet led directly to rapid
growth in the number of users online. This has driven technologists to make
even more changes in current protocols and to create new ones. Today, we
talk about the use of IPv6 (Internet Protocol version 6) to mitigate address-
ing concerns and for improving the methods we use to communicate over
the Internet. Over time, our ability to build a common interface to the
Internet has evolved with the improvements in hardware and software.
Using web browsers has led to a steady migration away from the traditional
data center model to a cloud-based model. Using technologies such as server
virtualization, parallel processing, vector processing, symmetric multipro-
cessing, and massively parallel processing has fueled radical change. Let’s
take a look at how this happened, so we can begin to understand more
about the cloud.
In order to discuss some of the issues of the cloud concept, it is impor-
tant to place the development of computational technology in a historical
context. Looking at the Internet cloud’s evolutionary development,
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and the
problems encountered along the way, provides some key reference points to
help us understand the challenges that had to be overcome to develop the
Internet and the World Wide Web (WWW) today. These challenges fell
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2 Cloud Computing
into two primary areas, hardware and software. We will look first at the
hardware side.
1.2 Hardware Evolution
Our lives today would be different, and probably difficult, without the ben-
efits of modern computers. Computerization has permeated nearly every
facet of our personal and professional lives. Computer evolution has been
both rapid and fascinating. The first step along the evolutionary path of
computers occurred in 1930, when binary arithmetic was developed and
became the foundation of computer processing technology, terminology,
and programming languages. Calculating devices date back to at least as
early as 1642, when a device that could mechanically add numbers was
invented. Adding devices evolved from the abacus. It was a significant mile-
stone in the history of computers. In 1939, the Berry brothers invented an
electronic computer capable of operating digitally. Computations were per-
formed using vacuum-tube technology.
In 1941, the introduction of Konrad Zuse’s Z3 at the German Labora-
tory for Aviation in Berlin was one of the most significant events in the evo-
lution of computers because this machine supported both floating-point
and binary arithmetic. Because it was a “Turing-complete” device,
2
it is con-
sidered to be the very first computer that was fully operational. A program-
ming language is considered Turing-complete if it falls into the same
computational class as a Turing machine, meaning that it can perform any
calculation a universal Turing machine can perform. This is especially sig-
nificant because, under the Church-Turing thesis,
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a Turing machine is the
embodiment of the intuitive notion of an algorithm. Over the course of the
next two years, computer prototypes were built to decode secret German
messages by the U.S. Army.
1. Paul Wallis, “A Brief History of Cloud Computing: Is the Cloud There Yet? A Look at the
Cloud’s Forerunners and the Problems They Encountered,” http://soa.sys-con.com/node/
581838, 22 Aug 2008, retrieved 7 Jan 2009.
2. According to the online encyclopedia Wikipedia, “A computational system that can com-
pute every Turing-computable function is called Turing-complete (or Turing-powerful).
Alternatively, such a system is one that can simulate a universal Turing machine.”
http://en.wikipedia.org/wiki/Turing_complete, retrieved 17 Mar 2009.
3. http://esolangs.org/wiki/Church-Turing_thesis, retrieved 10 Jan 2009.
Chap1.fm Page 2 Friday, May 22, 2009 11:24 AM
Hardware Evolution 3
1.2.1 First-Generation Computers
The first generation of modern computers can be traced to 1943, when the
Mark I and Colossus computers (see Figures 1.1 and 1.2) were developed,
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albeit for quite different purposes. With financial backing from IBM (then
International Business Machines Corporation), the Mark I was designed
and developed at Harvard University. It was a general-purpose electrome-
chanical programmable computer. Colossus, on the other hand, was an elec-
tronic computer built in Britain at the end 1943. Colossus was the world’s
first programmable, digital, electronic, computing device. First-generation
computers were built using hard-wired circuits and vacuum tubes (thermi-
onic valves). Data was stored using paper punch cards. Colossus was used in
secret during World War II to help decipher teleprinter messages encrypted
by German forces using the Lorenz SZ40/42 machine. British code breakers
referred to encrypted German teleprinter traffic as “Fish” and called the
SZ40/42 machine and its traffic “Tunny.”
5
To accomplish its deciphering task, Colossus compared two data
streams read at high speed from a paper tape. Colossus evaluated one data
stream representing the encrypted “Tunny,” counting each match that was
discovered based on a programmable Boolean function. A comparison
with the other data stream was then made. The second data stream was
generated internally and designed to be an electronic simulation of the
4. http://trillian.randomstuff.org.uk/~stephen/history, retrieved 5 Jan 2009.
5. http://en.wikipedia.org/wiki/Colossus_computer, retrieved 7 Jan 2009.
Figure 1.1 The Harvard Mark I computer. (Image from www.columbia.edu/acis/
history/mark1.html, retrieved 9 Jan 2009.)
Chap1.fm Page 3 Friday, May 22, 2009 11:24 AM
4 Cloud Computing
Lorenz SZ40/42 as it ranged through various trial settings. If the match
count for a setting was above a predetermined threshold, that data match
would be sent as character output to an electric typewriter.
1.2.2 Second-Generation Computers
Another general-purpose computer of this era was ENIAC (Electronic
Numerical Integrator and Computer, shown in Figure 1.3), which was built
in 1946. This was the first Turing-complete, digital computer capable of
being reprogrammed to solve a full range of computing problems,
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although earlier machines had been built with some of these properties.
ENIAC’s original purpose was to calculate artillery firing tables for the U.S.
Army’s Ballistic Research Laboratory. ENIAC contained 18,000 thermionic
valves, weighed over 60,000 pounds, and consumed 25 kilowatts of electri-
cal power per hour. ENIAC was capable of performing 100,000 calculations
a second. Within a year after its completion, however
,
the invention of the
transistor meant that the inefficient thermionic valves could be replaced
with smaller, more reliable components, thus marking another major step in
the history of computing.
Figure 1.2 The British-developed Colossus computer. (Image from www.com-
puterhistory.org, retrieved 9 Jan 2009.)
6. Joel Shurkin,
Engines of the Mind: The Evolution of the Computer from Mainframes to
Microprocessors,
New York: W. W. Norton, 1996.
Chap1.fm Page 4 Friday, May 22, 2009 11:24 AM
Hardware Evolution 5
Transistorized computers marked the advent of second-generation
computers, which dominated in the late 1950s and early 1960s. Despite
using transistors and printed circuits, these computers were still bulky and
expensive. They were therefore used mainly by universities and govern-
ment agencies.
The integrated circuit or microchip was developed by Jack St. Claire
Kilby, an achievement for which he received the Nobel Prize in Physics in
2000.
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In congratulating him, U.S. President Bill Clinton wrote, “You can
take pride in the knowledge that your work will help to improve lives for
generations to come.” It was a relatively simple device that Mr. Kilby
showed to a handful of co-workers gathered in the semiconductor lab at
Texas Instruments more than half a century ago. It was just a transistor and
a few other components on a slice of germanium. Little did this group real-
ize that Kilby’s invention was about to revolutionize the electronics industry.
1.2.3 Third-Generation Computers
Kilby’s invention started an explosion in third-generation computers.
Even though the first integrated circuit was produced in September 1958,
Figure 1.3 The ENIAC computer. (Image from www.mrsec.wisc.edu/.../computer/
eniac.html, retrieved 9 Jan 2009.)
7. http://www.ti.com/corp/docs/kilbyctr/jackstclair.shtml, retrieved 7 Jan 2009.
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