Connected: An Internet Encyclopedia
Connected: An Internet Encyclopedia
Programmed Instruction Course
Section 1 - Introduction
Prev: Section 1 - Introduction
Recently, everyone seems to have heard about the Internet, but
did you know that the net has been around since 1969?
I always like to start Internet classes with a review of
Don't worry if you don't understand all the terms;
the idea is to get a general picture of Internet history.
1969 - Birth of a Network
The Internet as we know it today, in the mid-1990s, traces it origins
back to a Defense Department project in 1969. The subject of the
project was wartime digital communications. At that time
the telephone system was about
the only theater-scale communications system in use.
A major problem had been identified in its design - its dependence
on switching stations that could be targeted during an attack.
Would it be possible to design a network that could quickly
reroute digital traffic around failed nodes?
A possible solution had been identified in theory. That was
to build a "web" of datagram network, called an "catenet",
and use dynamic routing protocols to constantly adjust the
flow of traffic through the catenet.
The Defense Advanced Research Projects Agency (DARPA) launched
the DARPA Internet Program.
1970s - Infancy
DARPA Internet, largely the plaything of academic and military researchers,
spent more than a decade in relative obscurity. As Vietnam, Watergate, the
Oil Crisis, and the Iranian Hostage Crisis rolled over the nation,
several Internet research teams proceeded through a gradual evolution
In 1975, DARPA declared the project a success and handed its management
over to the Defense Communications Agency.
Several of today's key protocols (including IP and TCP) were stable
by 1980, and adopted throughout ARPANET by 1983.
Mid 1980s - The Research Net
Let's outline key features, circa-1983, of what was then called
ARPANET. A small computer was a PDP-11/45, and a PDP-11/45 does not
fit on your desk. Some sites had a hundred computers attached
to the Internet. Most had a dozen or so, probably with something
like a VAX doing most of the work - mail, news, EGP routing.
Users did their work using DEC VT-100 terminals. FORTRAN was the
word of the day.
Few companies had Internet access, relying instead on
SNA and IBM mainframes. Rather, the Internet community was dominated
by universities and military research sites. It's most popular
service was the rapid email it made possible with distant colleagues.
In August 1983, there were 562 registered ARPANET hosts (RFC 1296).
UNIX deserves at least an honorable mention, since
almost all the initial Internet protocols were developed first
for UNIX, largely due to the availability of kernel source (for a price)
and the relative ease of implementation
(relative to things like VMS or MVS).
The University of California at Berkeley (UCB) deserves special mention,
because their Computer Science Research Group (CSRG) developed
the BSD variants of AT&T's UNIX operating system. BSD UNIX
and its derivatives would become the most common Internet programming
Many key features of the Internet were already in place,
including the IP and TCP protocols. ARPANET was fundamentally
unreliable in nature, as the Internet is still today. This
principle of unreliable delivery
means that the Internet only makes a
best-effort attempt to deliver packets. The network can
drop a packet without any notification to sender or receiver.
Remember, the Internet was designed for military survivability.
The software running on either end must be prepared to recognize
data loss, retransmitting data as often as necessary to achieve
its ultimate delivery.
Late 1980s - The PC Revolution
Driven largely by the development of the PC and LAN technology,
was standardized in 1985 when
RFC 950 was released.
LAN technology made the idea of a "catenet" feasible - an internetwork
of networks. Subnetting opened the possibilities of interconnecting
LANs with WANs.
The National Science Foundation (NSF) started the Supercomputer
Centers program in 1986. Until then, supercomputers such as Crays
were largely the playthings of large, well-funded universities
and military research centers.
NSF's idea was to make supercomputer resources available
to those of more modest means by constructing five
supercomputer centers around the country and building a network
linking them with potential users. NSF decided to base
their network on the Internet protocols, and NSFNET was
born. For the next decade, NSFNET would be the core
of the U.S. Internet, until its privatization and
ultimate retirement in 1995.
Domain naming was stable by 1987 when
RFC 1034 was released.
Until then, hostnames were mapped to IP address using static tables,
but the Internet's exponential growth had made this practice infeasible.
In the late 1980s, important advances related poor network performance
with poor TCP performance, and a string of papers by the likes of
Nagle and Van Jacobson
present key insights into TCP performance.
The 1987 Internet Worm was the largest security failure in
the history of the Internet. All things considered, it could happen
Early 1990s - Address Exhaustion and the Web
In the early 90s, the first address exhaustion crisis
hit the Internet technical community. The present solution,
will sustain the Internet for a few more years by making
more efficient use of IP's existing 32-bit address space.
For a more lasting
solution, IETF is looking at IPv6 and its 64-bit address space,
but CIDR is here to stay.
Crisis aside, the World Wide Web (WWW) has been one of Internet's
most exciting recent developments. The idea of
has been around for more than a decade, but in 1989 a team at
the European Center for Particle Research (CERN) in Switzerland
developed a set of protocols for transferring hypertext
via the Internet. In the early 1990s it was enhanced by a team
at the National Center for Supercomputing Applications (NCSA)
at the University of Illinois - one of NSF's supercomputer centers.
The result was NCSA Mosaic, a graphical, point-and-click hypertext
browser that made Internet easy. The resulting explosion
in "Web sites" drove the Internet into the public eye.
Mid 1990s - The New Internet
Of at least as much interest as Internet's technical progress in the
1990s has been its sociological progress.
It has already become part
of the national vocabulary, and seems headed for even greater prominence.
It has been accepted by the business community, with a resulting
explosion of service providers, consultants, books, and TV coverage.
It has given birth to the Free Software Movement.
The Free Software Movement owes much to bulletin board systems,
but really came into its own on the Internet, due to a combination
of forces. The public nature of the Internet's early funding ensured
that much of its networking software was non-proprietary. The
emergence of anonymous FTP sites provided a distribution mechanism
that almost anyone could use. Network newsgroups and mailing lists
offered an open communication medium. Last but not least were
individualists like Richard Stallman, who wrote EMACS, launched the GNU
Project and founded the Free Software Foundation. In the 1990s, Linus
Torvalds wrote Linux, the popular (and free) UNIX clone operating system.
The explosion of capitalist conservatism, combined with a growing
awareness of Internet's business value, has led to major
changes in the Internet community.
Many of them have not been for the good.
First, there seems to be a growing departure from Internet's history
of open protocols, published as RFCs. Many new protocols are
being developed in an increasingly proprietary manner.
IGRP, a trademark of Cisco Systems, has the dubious distinction
as the most successful proprietary Internet routing protocol,
capable only of operation between Cisco routers.
Other protocols, such as BGP, are published as RFCs, but
with important operational details omitted.
The notoriously mis-named Open Software Foundation has
introduced a whole suite of "open" protocols whose
specifications are available - for a price - and not on the net.
I am forced to wonder: 1) why do we need a new RPC? and
2) why won't OSF tell us how it works?
People forget that businesses have tried to
run digital communications networks in the past.
IBM and DEC both developed proprietary networking schemes
that only ran on their hardware. Several information
providers did very well for themselves in the 80s, including
LEXIS/NEXIS, Dialog, and Dow Jones. Public data networks were
constructed by companies like Tymnet and run into every major US city.
CompuServe and others built large bulletin board-like systems.
Many of these services still offer a quality and depth of coverage
unparalleled on the Internet (examine Dialog if you are skeptical
of this claim). But none of them offered nudie
GIFs that anyone could download. None of them let you read
through the RFCs and then write a Perl script to tweak the one
little thing you needed to adjust. None of them
gave birth to a Free Software Movement.
None of them caught people's imagination.
The very existence of the Free Software Movement is part of the
Internet saga, because free software would not exist without the net.
"Movements" tend to arise when progress offers us new freedoms
and we find new ways to explore and, sometimes, to exploit them.
The Free Software Movement has offered what would be
unimaginable when the Internet was formed - games, editors,
compilers, networking software, and even entire operating systems
available for anyone who wants them, without licensing fees,
with complete source code, and all you need is Internet access.
It also offers challenges, forcing us to ask what changes are
needed in our society to support these new freedoms that have
touched so many people. And it offers chances at exploitation,
from the businesses using free software development platforms
for commercial code, to the Internet Worm and the security
risks of open systems.
People wonder whether progress is better served through
government funding or private industry.
The Internet defies the popular wisdom of "business is better".
Both business and government tried to
build large data communication networks in the 1980s. Business depended
on good market decisions; the government researchers
based their system on openness, imagination and freedom.
Business failed; Internet succeeded.
Our reward has been its commercialization.
For the next few years, the Internet will almost certainly be
content-driven. Although new protocols are always under development,
we have barely begun to explore the potential
of just the existing ones.
Chief among these is the World Wide Web, with its potential for
simple on-line access to almost any information imaginable.
Yet even as the Internet intrudes into society, remember
that over the last two decades "The Net" has developed
a culture of its own, one that may collide with society's.
Already business is making its pitch to dominate the Internet.
Already Congress has deemed it necessary to regulate the Web.
The big questions loom unanswered:
How will society change the Internet...
and how will the Internet change society?
Connected: An Internet Encyclopedia