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A Brief
History of Computing
From:
Stephen White

Part - 2
Hardware History Overview
(Suite)
Background of the ARPANET
The earliest ideas of a computer network intended to allow general
communication between users of various computers was formulated by J.C.R.
Licklider of MIT in August 1962, in a series of memos discussing his "Galactic
Network" concept. These ideas contained almost everything that the Internet is
today. In October 1962 Licklider was appointed head of the Behavioral Sciences
and Command and Control programs at ARPA (as it was then called), the United
States Department of Defense Advanced Research Projects Agency. He would then
convince Ivan Sutherland and Bob Taylor that this was a very important concept,
although he left ARPA before any actual work on his vision was performed.
Separately, Paul Baran had started work in 1959 at the RAND corporation on
secure communications technologies that could enable a military communications
network to withstand a nuclear attack. His results, published in a series of
studies starting in 1960, described two key ideas: first, use of a decentralized
network with multiple paths between any two points; and second, dividing
complete user messages into what he called message blocks before sending them
into the network. This first allowed the elimination of single points of failure,
and enabled the network to automatically and efficiently work around any
failures. A summary paper describing the entire scheme was presented in 1962,
and published in 1964.
Leonard Kleinrock had performed tests on store and forward message systems in
1961, and wrote a very important book in 1964 covering queueing theory and
routing in store and forward networks, although this work did not include the
concept of breaking a user's message up into smaller units for transmission
through the network.
Finally, Donald Davies of NPL had begun working with related concepts 1965,
after a conference on in the United Kingdom on time-sharing brought up the
inadequacies of existing circuit-switched networks. His work was originally
independently of Baran's work, although Davies learned of it after he gave a
seminar on his ideas at NPL in 1966; incidentally, it was Davies who introduced
the term packet.
Thus, the ideas that were to become the ARPANET came from three independent
research centers: DARPA, NPL (in the UK) and the RAND corporation.
Creation of the ARPANET
By the summer of 1968, a complete plan had been prepared, and after approval
at ARPA, a Request For Quotation (RFQ) was sent to 140 potential bidders. Most
regarded the proposal as outlandish, and only 12 companies submitted bids, of
which only four were regarded as in the top rank. By the end of the year, the
field had been narrowed to two, and after negotiations, a final choice was made,
and the contract was awarded to Bolt, Beranek and Newman (BBN) early in 1969 (see:
7 April 1969 and Request for Comments).
Initial ARPANET deployment
There were four nodes on the initial ARPANET. Each was connected to a small
computer known as an Interface Message Processor or IMP. The IMPs at each site
performed the function of a router, and were to be connected to each other using
64 kbit/second digital links over leased lines. The first four were installed at
UCLA (where Kleinrock had established a Network Measurement Center), the
Stanford Research Institute (where Doug Engelbart had worked on his "NLS"
project, an early hypertext system), UCSB, and University of Utah.
The first ARPANET link was established on November 21 1969, between an IMP at
UCLA and another at the Stanford Research Institute in Menlo Park. By December
5, 1969, the entire 4-node network was connected.
Origins of the ARPANET
While all this was happening, ARPA and Taylor continued to be interested in
creating a computer communication network, in part to allow ARPA-sponsored
researchers in various locations to use various computers which ARPA was
providing, and in part to quickly make new software and other results widely
available.
At the end of 1966, Taylor brought Lawrence G. Roberts to ARPA from MIT Lincoln
Laboratory to head a project to create the network; Roberts had previously
encountered Davies at the time-sharing conference.
Roberts' initial concept was to hook the various time-sharing machines directly
to each other, through telephone lines. At an early meeting in 1967, many of the
participants were unenthusiastic at having the load of managing this line put
directly on their computer. One of the participants, Wesley Clark, came up with
the idea of using separate smaller computers to manage the communication links;
the small computers would then be connected to the large time-sharing main-frame
computers. Initial planning for the ARPANET began on that basis.
Roberts then proceeded to author a "plan for the ARPANET", which was presented
at a symposium in 1967; also presenting there was Roger Scantlebury, from Davies'
group at NPL. He discussed packet switching with Roberts, and introduced Roberts
to Baran's work. The exact impact is unclear, but Roberts' plans for the network
were soon modified after his meeting with Scantlebury.
Retrospective
The support and style of management by ARPA was crucial to the success of
ARPANET. As the Internet develops and the struggle over the role the Internet
plays unfolds, it will be important to remember how the network developed and
the culture that it was connected with. (As a facilitator of communication, the
culture of the Net is an important feature to acknowledge.) The ARPANET
Completion Report, as published jointly by BBN of Cambridge, Mass., and ARPA
concludes by stating:
"...it is somewhat fitting to end on the note that the ARPANET program has had a
strong and direct feedback into the support and strength of computer science,
from which the network itself sprung." (Chapter III, pg.132, Section 2.3.4)
In order to understand the wonder that the Internet, and various parts of the
Net, represent, we need to understand why the ARPANET Completion report ends
with the suggestion that the ARPANET is fundamentally connected to and born of
computer science.
Motivation for the Internet
The need for an internetwork appeared with ARPA's sponsorship, by Robert
Kahn, of the development of a number of innovative networking technologies; in
particular, the first packet radio networks (inspired by the ALOHA network), and
a satellite packet communication program. Later, local area networks (LAN's)
would also join the mix.
Connecting these disparate networking technologies was not possible with the
kind of protocols used on the ARPANET, which depended on the exact nature of the
subnetwork. A wholly new kind of networking architecture was needed.
Early Internet work
Kahn recruited Vint Cerf to work with him on the problem, and they soon
worked out a fundamental reformulation, where instead of the network being
responsible for reliability, as in the ARPANET, the hosts became responsible.
Cerf credits Herbert Zimmerman and Louis Pouzin (designer of the CYCLADES
network) with important influences on this design. Some accounts also credit the
early networking work at Xerox PARC with an important technical influence.
With the role of the network reduced to the bare
minimum,
it became possible to join almost any networks together, no matter what
their characteristics, thereby solving Kahn's initial problem. (One popular
saying has it that TCP/IP, the eventual product of Cerf and Kahn's work, will
run over "two tin cans and a string".) A computer called a gateway (a name later
changed to router to avoid confusion with a number of other kinds of devices,
also called gateways) is provided with an interface to each network, and
forwards packets back and forth between them.
Happily, this new concept was a perfect fit with the newly
emerging local area networks, which were revolutionizing communication between
computers within a site.
Early growth
In 1983, TCP/IP protocols replaced the earlier NCP
protocol as the principal protocol of the ARPANET;
in 1984, the US military
portion of the ARPANet was broken off as a separate network, the MILNET.
The early Internet, based around the ARPANET, was government-funded and
therefore restricted to non-commercial uses such as research; un-related
commercial use was strictly forbidden. This initially restricted connections to
military sites and universities. During the 1980s, the connections expanded to
more educational institutions, and even to a growing number of companies such as
Digital Equipment Corporation and Hewlett-Packard, which were participating in
research projects, or providing services to those who were.
Another branch of the US government, the National Science Foundation, became
heavily involved in the Internet in the mid 1980s. The NSFNet backbone, intended
to connect and provide access to a number of supercomputing centers established
by the NSF, was established in 1986.
At the end of the 1980s, the US Department of Defense decided the network was
developed enough for its initial purposes, and decided to stop further funding
of the core Internet backbone. The ARPANET was to be gradually shut down (its
last node was turned off in 1989), and NSF took over responsibility for
providing long-haul connectivity in the US.
In another NSF initiative, regional TCP/IP-based networks such as NYSERNet (New
York State Education and Research Network) and BARRNet (Bay Area Regional
Research Network), grew up and started interconnecting with the nascent
Internet. This greatly expanded the reach of the growing network, and when in
the early 1990s the NSF decided to allow commercial access to the Internet
components they had initiated, that was to a great extent the point where the
growth of the Internet really took off.
Commercialization and
privatization
Parallel to the Internet, other networks were growing. Some were educational
and centrally-organized like BITNET and CSNET. Others were a grass-roots mix of
school, commercial, and hobby like the UUCP network.
During the late 1980s the first Internet Service Provider companies were formed.
Companies like PSINet, UUNET, Netcom, and Portal were formed to provide service
to the regional research networks and provide alternate network access (like
UUCP-based email and Usenet News) to the public.
The interest in commercial use of the Internet became a hotly-debated topic.
Although commercial use was forbidden, the exact definition of commercial use
could be unclear and subjective. Everyone agreed that one company sending an
invoice to another company was clearly commercial use, but anything less was up
for debate. The alternate networks, like UUCP, had no such restrictions, so many
people were skirting grey areas in the interconnection of the various networks.
Many university users were outraged at the idea of non-educational use of their
networks. Ironically it was the commercial Internet service providers who
brought prices low enough that junior colleges and other schools could afford to
participate in the new arenas of education and research.
By 1994, the NSFNet lost its standing as the backbone of the Internet. Other
competing commercial providers created their own backbones and interconnections.
Regional NAPs (network access points) became the primary interconnections
between the many networks. The NSFNet was dropped as the main backbone, and
commercial restrictions were gone.
Early applications
E-mail had existed as a message exchanging service on early time sharing
mainframe computers connected to a number of terminals. In about 1971 it
developed into the first system of exchanging addressed messages between
different, networked computers; in 1972 Ray Tomlinson introduced the "name@computer"
notation that is still used today. E-mail turned into the internet "killer
application" of the 1980s.
The second most popular application of the early internet was usenet, a system
of distributed discussion groups which is still going strong today. Usenet had
existed even before the internet, as an application of Unix computers connected
by telephone lines via the UUCP protocol.
It wasn't until the early to mid 1980s that the services we now use most on the
Internet started appearing. The concept of "domain names" (like "wikipedia.org")
requiring "Domain Name Servers" wasn't even introduced until 1984. Before that
all the computers were just addressed by their IP addresses (numbers) or used a
central "hosts" file maintained by the NIC. Most protocols used for email and
other services were significantly enhanced after this.
Standards and control
The Internet has developed a significant subculture dedicated to the idea that
the Internet is not owned or controlled by any one person, company, group, or
organization. Nevertheless, some standardization and control is necessary for
anything to function.
Many people wanted to put their ideas into the standards for communication
between the computers that made up this network, so a system was devised for
putting forward ideas. One would write one's ideas in a paper called a "Request
for Comments" (RFC for short), and let everyone else read it. People commented
on and improved those ideas in new RFCs. (With its basis as an educational
research project, much of the documentation was written by students or others
who played significant roles in developing the network but did not have official
responsibility for defining standards. This is the reason for the very low-key
name of "Request for Comments" rather than something like "Declaration of
Official Standard".) The first RFC (RFC1) was written on April 7th, 1969. There
are now over 3500 RFCs, describing every aspect of how the internet functions.
The Internet standards process has been as innovative as the Internet itself.
Prior to the Internet, standardization was a slow process run by committees with
arguing vendor-driven factions and lengthy delays. In networking in particular,
the results were monstrous patchworks of bloated specifications.
The fundamental requirement for a networking protocol to become an Internet
standard is the existence of at least two working implementations that
interoperate with each other. This makes sense looking back, but it was a new
concept at the time. Other efforts built huge specifications with many optional
parts and then expected people to go off and implement them, and only later did
people find that they did not interoperate, or worse, the standard was not even
implementable.
In the 1980s, the International Organization for
Standardization (ISO) documented a new effort in networking called Open Systems
Interconnect or OSI. Prior to OSI, networking was completely vendor-developed
and proprietary. OSI was a new industry effort, attempting to get
everyone to agree to common network standards to provide multi-vendor
interoperability. The OSI model was the most important advance in
teaching network concepts. However, the OSI protocols or "stack" that were
specified as part of the project were a bloated mess. Standards like X.400
for e-mail took up several large books, while Internet e-mail took only a few
dozen pages at most in RFC-821 and 822. Most
protocols and specifications in the OSI stack, such as token-bus media,
CLNP packet delivery, FTAM file transfer, and X.400
e-mail, are long-gone today. Only one, X.500 directory service,
still survives with significant usage, mainly because
the original unwieldy protocol has been stripped away and effectively replaced
with LDAP.
Some formal organization is necessary to make things
operate. The first central authority was the NIC (Network Information Center) at
SRI (Stanford Research Institute in Menlo Park, California).
The Lyman Years: 1970-1980
The Kennedy Years: 1980-1992
Stanford
Research Institute in Menlo Park
Lyman's tenure also saw an
increase in the numbers and influence of women and members of ethnic minorities
as faculty and students. During the summer of 1980, Lyman left Stanford to
become president of the Rockefeller Foundation, a philanthropic organization
he previously had served as a board member.
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From Jeff Koftinoff
few extract
Other
Rockefeller Foundation
prominent Canadian members include: Gerald Bouey [former Governor
of the Bank of Canada who had fin]; Conrad Black, newspaper magnate and chairman of Argus;
John Allen, CEO of Stelco; Raymond Cyr, President of Bell Canada Enterprises;
Peter Dobell, of Foreign Affairs and Foreign Trade, in Ottawa; Marie-Jose
Druin, Hudson Institute of Canada; Claude Edwards, Public Staff Relations
Board in Ottawa; Allan Gottlieb, former Canadian Ambassador to the U.S.;
David Henniger, Regional Director of Burns, Fry; Senator Duff Roblin; Ron
Sutherland, CEO of ATCO Ltd., William Turner, of Montreal's PCC Industrial
Corporation; and J.H. Warren, former Canadian Ambassador to the
U.S.
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He returned to campus in 1988 to
become the inaugural director of the university's Institute for International
Studies. He retired from the institute as an emeritus professor in 1991.
August 1977 development assistance
requested
December 10, 1980
illegal publication of:
ACILR-CDRIL Tome II and IV by
Power corporation
Press Publication owned by P. Desmarais
A pioneer in computer
architecture, in 1981 Dr. Hennessy drew together researchers to focus on
a computer architecture known as RISC (Reduced Instruction Set Computer), a
technology that has revolutionized the computer industry by increasing
performance while reducing costs.
In addition to his role in the basic research,
Dr. Hennessy helped transfer this technology to industry. In
1984, he confounded MIPS Computer Systems, now MIPS Technologies, which designs
microprocessors. In recent years, his research has focused on the architecture
of high-performance computers.
Dr. Hennessy is a recipient of the 2000 John Von Neumann
Medal, the 2000 ASEE R. Lamme Medal, the 2001 Eckert Mauchly Award and the 2001
Seymour Cray Award. He is a member of the National Academy of Engineering and
the National Academy of Sciences, and he is a fellow of the American Academy of
Arts and Sciences, the Association for Computing Machinery, and the Institute of
Electrical and Electronics Engineers.
The Kennedy Years, 1980-1992
Stanford celebrated its centennial and
its full emergence as a world-class university under Donald Kennedy, who had
served his predecessor Richard Lyman as vice president and provost since 1979.
Kennedy, holder of three degrees from Harvard, joined Stanford's biology faculty
in 1960 and while on leave from 1977 to 1979 served in Washington, D.C., as
commissioner of the Food and Drug Administration.
During Kennedy's presidency, Stanford
completed the $1.26 billion Centennial Campaign, at the time the largest
fund-raising success in the history of higher education. He was at the forefront
of the university's student public service initiative and efforts to renew
faculty commitment to teaching as "first of our labors."His tenure was marked by
the creation of major new facilities -- the value of the physical plant more
than doubled during his term.
Yet his record was overshadowed by the university's
disagreement with the federal government over reimbursement for the indirect
costs of research. In July 1991, one week after announcing a program to reform
university financial systems to improve the university's accountability for
public funds, Kennedy announced he would resign the following summer, saying: "It
is very difficult . . . for a person identified with a problem to be the
spokesman for its solution. We need to . . . look to the future as we resolve
the problems of the past." In 1994, the government reached a settlement with the
university concerning the billing of expenses for federally sponsored research.
The Office of Naval Research, the government agency that oversees Stanford's
research contracts with all federal agencies, said that it did "not have a claim
that Stanford engaged in fraud, misrepresentation or other wrongdoing."
Kennedy is presently the Bing Professor of Environmental
Science and a senior fellow at the Institute for International Studies.
World Wide Web Origins
One of the parts of the Internet
many people are most familiar with is the World Wide Web.
As the Internet grew through the 1980s and early
1990s, many people realized the growing need to be able to find and organize
files and related information.
Projects such as Gopher, WAIS, and the Anonymous FTP Archive Site list
attempted to create schemes to organize distributed data and present it to
people in an easy-to-use form. Unfortunately, these projects fell short in being
able to accommodate all the various existing file and data types, and in being
able to grow without centralized bottlenecks.
One of the most promising ideas was hypertext, inspired by Vannevar Bush's "memex",
Ted Nelson's Project Xanadu and the Note Code Project. Small self-contained
hypertext systems had been created before, such as Apple Computer's HyperCard,
but
before the Internet, nobody had worked out how to scale it up so that it could
to refer to another document anywhere in the world.
The solution was invented by Tim Berners-Lee in 1989.
He was a physicist working at CERN, the European Particle Physics Laboratory,
and wanted a way for physicists to share information about their research. His
documentation project was the source of the two key inventions that made the
World Wide Web possible.
The two key inventions were the uniform resource locator (URL) and hypertext
markup language (HTML). The URL was a simple way to specify the location of a
document anywhere on the Internet in one simple name that specified a computer
name, a file identification on that machine, and a protocol to use. HTML was an
easy way to embed codes into a text file that could define the structure of a
document and also include links pointing to other documents. An additional
network protocol, a hypertext transfer protocol (HTTP), was also invented for
reduced overhead in transfers, but the true genius of the new system was that a
new protocol was useful but not necessary; the URL and HTML system was backwards
compatible with existing protocols like FTP and Gopher.
Later around 1992 people realized that the simple markup capabilities of HTML
could allow graphics to be included in text documents. The first graphical web
browsers were developed, Viola and Mosaic. Mosaic was developed by a team at the
National Center for Supercomputing Applications at the University of Illinois at
Urbana-Champaign (NCSA-UIUC), led by Marc Andreesen. Andreesen left NCSA-UIUC
and joined Jim Clark, one of the founders of SGI (Silicon Graphics, Inc.).
They started Mosaic Communications which became
Netscape Communications Corporation , making Netscape Navigator the first
commercially successful browser.
Microsoft acquired technology from SpyGlass (who got their technology from NCSA)
to develop Internet Explorer.
The ease of creating new Web documents and linking to existing ones caused
exponential growth. As the Web grew, search engines were created to track pages
on the web and allow people to find things. The first search engine, Lycos, was
created in 1993 as a university project. In 1993, the first web magazine, The
Virtual Journal, was published by a University of Maine student. At the end of
1993, Lycos indexed a total of 800,000 web pages.
By August 2001, the Google search engine tracked over 1.3 billion web pages and
the growth continues. In early 2004, Google's index exceeded 4 billion pages.
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