6 Cloud Computing
microchips were not used in computers until 1963. While mainframe
computers like the IBM 360 increased storage and processing capabilities
even further, the integrated circuit allowed the development of minicom-
puters that began to bring computing into many smaller businesses.
Large-scale integration of circuits led to the development of very small
processing units, the next step along the evolutionary trail of computing.
In November 1971, Intel released the world’s first commercial micropro-
cessor, the Intel 4004 (Figure 1.4). The 4004 was the first complete CPU
on one chip and became the first commercially available microprocessor.
It was possible because of the development of new silicon gate technology
that enabled engineers to integrate a much greater number of transistors
on a chip that would perform at a much faster speed. This development
enabled the rise of the fourth-generation computer platforms.
1.2.4 Fourth-Generation Computers
The fourth-generation computers that were being developed at this time
utilized a microprocessor that put the computer’s processing capabilities on
a single integrated circuit chip. By combining random access memory
(RAM), developed by Intel, fourth-generation computers were faster than
ever before and had much smaller footprints. The 4004 processor was
capable of “only” 60,000 instructions per second. As technology pro-
gressed, however, new processors brought even more speed and computing
capability to users. The microprocessors that evolved from the 4004
allowed manufacturers to begin developing personal computers small
enough and cheap enough to be purchased by the general public. The first
commercially available personal computer was the MITS Altair 8800,
released at the end of 1974. What followed was a flurry of other personal
computers to market, such as the Apple I and II, the Commodore PET, the
Figure 1.4 The Intel 4004 processor. (Image from www.thg.ru/cpu/20051118/
index.html, retrieved 9 Jan 2009.)
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Internet Software Evolution 7
VIC-20, the Commodore 64, and eventually the original IBM PC in
1981. The PC era had begun in earnest by the mid-1980s. During this
time, the IBM PC and IBM PC compatibles, the Commodore Amiga, and
the Atari ST computers were the most prevalent PC platforms available to
the public. Computer manufacturers produced various models of IBM PC
compatibles. Even though microprocessing power, memory and data stor-
age capacities have increased by many orders of magnitude since the inven-
tion of the 4004 processor, the technology for large-scale integration (LSI)
or very-large-scale integration (VLSI) microchips has not changed all that
much. For this reason, most of today’s computers still fall into the category
of fourth-generation computers.
1.3 Internet Software Evolution
The Internet is named after the Internet Protocol, the standard communi-
cations protocol used by every computer on the Internet. The conceptual
foundation for creation of the Internet was significantly developed by
three individuals. The first, Vannevar Bush,
8
wrote a visionary description
of the potential uses for information technology with his description of an
automated library system named MEMEX
(see Figure 1.5)
.
Bush intro-
duced the concept of the MEMEX in the 1930s as a microfilm-based
“device in which an individual stores all his books, records, and communi-
cations, and which is mechanized so that it may be consulted with exceed-
ing speed and flexibility.”
9
8. http://en.wikipedia.org/wiki/Vannevar_Bush, retrieved 7 Jan 2009.
Figure 1.5 Vannevar Bush’s MEMEX. (Image from www.icesi.edu.co/
blogs_estudiantes/luisaulestia, retrieved 9 Jan 2009.)
9. http://www.livinginternet.com/i/ii_summary.htm, retrieved 7 Jan 2009.
Chap1.fm Page 7 Friday, May 22, 2009 11:24 AM
8 Cloud Computing
After thinking about the potential of augmented memory for several
years, Bush wrote an essay entitled “As We May Think” in 1936. It was
finally published in July 1945 in the
Atlantic Monthly
. In the article, Bush
predicted: “Wholly new forms of encyclopedias will appear, ready made
with a mesh of associative trails running through them, ready to be dropped
into the MEMEX and there amplified.”
10
In September 1945,
Life
maga-
zine published a condensed version of “As We May Think” that was accom-
panied by several graphic illustrations showing what a MEMEX machine
might look like, along with its companion devices.
The second individual to have a profound effect in shaping the Internet
was Norbert Wiener. Wiener was an early pioneer in the study of stochastic
and noise processes. His work in stochastic and noise processes was relevant
to electronic engineering, communication, and control systems.
11
He also
founded the field of cybernetics. This field of study formalized notions of
feedback and influenced research in many other fields, such as engineering,
systems control, computer science, biology, philosophy, etc. His work in
cybernetics inspired future researchers to focus on extending human capa-
bilities with technology. Influenced by Wiener, Marshall McLuhan put
forth the idea of a
global village
that was interconnected by an electronic
nervous system as part of our popular culture.
In 1957, the Soviet Union launched the first satellite,
Sputnik I,
prompting U.S. President Dwight Eisenhower to create the Advanced
Research Projects Agency (ARPA) agency to regain the technological lead in
the arms race. ARPA (renamed DARPA, the Defense Advanced Research
Projects Agency, in 1972) appointed J. C. R. Licklider to head the new
Information Processing Techniques Office (IPTO). Licklider was given a
mandate to further the research of the SAGE system. The SAGE system (see
Figure 1.6) was a continental air-defense network commissioned by the
U.S. military and designed to help protect the United States against a space-
based nuclear attack. SAGE stood for Semi-Automatic Ground Environ-
ment.
12
SAGE was the most ambitious computer project ever undertaken at
the time, and it required over 800 programmers and the technical resources
of some of America’s largest corporations. SAGE was started in the 1950s
and became operational by 1963. It remained in continuous operation for
over 20 years, until 1983.
10. http://www.theatlantic.com/doc/194507/bush, retrieved 7 Jan 2009.
11. http://en.wikipedia.org/wiki/Norbert_Wiener, retrieved 7 Jan 2009.
12. http://www.computermuseum.li/Testpage/IBM-SAGE-computer.htm, retrieved 7 Jan 2009.
Chap1.fm Page 8 Friday, May 22, 2009 11:24 AM
Internet Software Evolution 9
While working at ITPO, Licklider evangelized the potential benefits of
a country-wide communications network. His chief contribution to the
development of the Internet was his ideas, not specific inventions. He fore-
saw the need for networked computers with easy user interfaces. His ideas
foretold of graphical computing, point-and-click interfaces, digital libraries,
e-commerce, online banking, and software that would exist on a network
and migrate to wherever it was needed. Licklider worked for several years at
ARPA, where he set the stage for the creation of the ARPANET. He also
worked at Bolt Beranek and Newman (BBN), the company that supplied
the first computers connected on the ARPANET.
After he had left ARPA, Licklider succeeded in convincing his
replacement to hire a man named Lawrence Roberts, believing that Rob-
erts was just the person to implement Licklider’s vision of the future net-
work computing environment. Roberts led the development of the
network. His efforts were based on a novel idea of “packet switching” that
had been developed by Paul Baran while working at RAND Corporation.
The idea for a common interface to the ARPANET was first suggested in
Ann Arbor, Michigan, by Wesley Clark at an ARPANET design session
set up by Lawrence Roberts in April 1967. Roberts’s implementation plan
called for each site that was to connect to the ARPANET to write the soft-
ware necessary to connect its computer to the network. To the attendees,
Figure 1.6 The SAGE system. (Image from USAF Archives, retrieved from http://
history.sandiego.edu/GEN/recording/images5/PDRM0380.jpg.)
Chap1.fm Page 9 Friday, May 22, 2009 11:24 AM
10 Cloud Computing
this approach seemed like a lot of work. There were so many different
kinds of computers and operating systems in use throughout the DARPA
community that every piece of code would have to be individually writ-
ten, tested, implemented, and maintained. Clark told Roberts that he
thought the design was “bass-ackwards.”
13
After the meeting, Roberts stayed behind and listened as Clark elabo-
rated on his concept to deploy a minicomputer called an Interface Message
Processor (IMP, see Figure 1.7) at each site. The IMP would handle the
interface to the ARPANET network. The physical layer, the data link layer,
and the network layer protocols used internally on the ARPANET were
implemented on this IMP. Using this approach, each site would only have
to write one interface to the commonly deployed IMP. The host at each site
connected itself to the IMP using another type of interface that had differ-
ent physical, data link, and network layer specifications. These were speci-
fied by the Host/IMP Protocol in BBN Report 1822.
14
So, as it turned out, the first networking protocol that was used on the
ARPANET was the Network Control Program (NCP). The NCP provided
the middle layers of a protocol stack running on an ARPANET-connected
host computer.
15
The NCP managed the connections and flow control
among the various processes running on different ARPANET host comput-
ers. An application layer, built on top of the NCP, provided services such as
email and file transfer. These applications used the NCP to handle connec-
tions to other host computers.
A minicomputer was created specifically to realize the design of the
Interface Message Processor. This approach provided a system-independent
interface to the ARPANET that could be used by any computer system.
Because of this approach, the Internet architecture was an open architecture
from the very beginning. The Interface Message Processor interface for the
ARPANET went live in early October 1969. The implementation of the
architecture is depicted in Figure 1.8.
13. http://www.urbandictionary.com/define.php?term=Bass+Ackwards defined this as “The art
and science of hurtling blindly in the wrong direction with no sense of the impending
doom about to be inflicted on one’s sorry ass. Usually applied to procedures, processes, or
theories based on faulty logic, or faulty personnel.” Retrieved 8 Jan 2009.
14. Frank Heart, Robert Kahn, Severo Ornstein, William Crowther, and David Walden, “The
Interface Message Processor for the ARPA Computer Network,”
Proc. 1970 Spring Joint
Computer Conference
36:551–567, AFIPS, 1970.
15. http://www.answers.com/topic/network-control-program, retrieved 8 Jan 2009.
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