1. EDU626 Integrating Educational Technology
Summer 2012
The Links that Became
a Web
The 40-year Old Internet and the 20-Year Old
Web

2. 2
First: What is the Internet?
For one thing, it‟s not really “the
net”, it‟s the “nets”:
– The internet is “a cooperatively-run
collection of computer networks that
span the globe.”

3. A formal definition
Internet
– The high-speed fiber-optic network of networks
that uses TCP/IP protocols to interconnect
computer networks around the world, enabling
users to communicate via e-mail, transfer data
and program files via FTP, find information on
the World Wide Web, and access remote
computer systems such as online catalogs and
electronic databases easily and effortlessly,
using an innovative technique called packet
switching. The Internet began in 1969 as
ARPAnet, a project of the U.S. Department of
Defense.

4. Cold War Technology?
 Originally designed by the U.S. Department of
Defense so that a communication signal could
withstand nuclear war and serve military
institutions worldwide, the Internet was first
known as the ARPANet, the most robust
communication technology. It is a system of linked
computer networks, international in scope, that
facilitates data transfer and communication
services, such as remote login, file transfer (FTP),
electronic mail (e-mail), newsgroups, and the
World Wide Web. The Internet greatly extends the
reach of each connected computer network (see:
network effect, IP).
– Internet

5. Before ARPANet
 Before ARPANET, most computer systems consisted
of a massive computer -- sometimes the size of an
entire room -- with user terminals hardwired to it. A
terminal was some form of user interface, often
consisting of a keyboard or punch card reader.
Multiple users could access the computer
simultaneously, in a technique called timesharing.
Other early networks required a direct connection
between host computers, meaning that there was
only one path for information to flow through. The
direct connections limited the size of these computer
networks, which became known as local area
networks (LANs).
– How ARPANET Works

6. Phone-linked networks
“In the 1960s, as many as a few hundred
users could have accounts on a single large
computer using terminals, and exchange
messages and files between them. But each
of those little communities was an
island, isolated from others. By reliably
connecting different kinds of computers to
each other, the ARPANET took a crucial
step toward the online world that links
nearly a third of the world's population
today.”
– Marc Weber, founding curator of the Computer History
Museum’s Internet History Program
On October 29, 2009, SRI celebrated
the 40th anniversary of the first
ARPANET connection.

7. From mainframes to minicomputers
 Before ARPANET, most computer systems
consisted of a massive computer -- sometimes the
size of an entire room -- with user terminals
hardwired to it.
What is a
mainframe
computer?

8. The 1957 vision of computers

9. Minicomputers?
 Minicomputers are a largely obsolete class of
multi-user computers which made up the
middle range of the computing spectrum, in
between the largest multi-user systems
(mainframe computers) and the smallest
single-user systems (microcomputers or
personal computers).
From Blog “Health Care
Renewal”:
[a] picture from the George
Washington High School
(Phila., PA) 1973 yearbook in
front of [their] high school's
DEC PDP-8/S:

10. When did ARPAnet become the Internet?
 “. . . Ray Tomlinson is credited with inventing
email in 1972. . . . He picked the @ symbol from
the computer keyboard to denote sending
messages from one computer to another. So then,
for anyone using Internet standards, it was
simply a matter of nominating name-of-the-
user@name-of-the-computer.
 “. . . 1975 seems to be the definitive year in which,
for the first time, networks connected to each
other.”
– Ian Peter’s History of the Internet

11. 1975, the net goes commercial
Telenet
– One of the first value-added, packet switching
networks that enabled terminals and computers
to exchange data. Established in 1975 by Dr.
Lawrence Roberts, who helped to develop
ARPANET, Telenet was acquired by GTE in
1979. After it was acquired by Sprint in 1986, it
was renamed SprintNet

12. Packet switching?
Almost like USPS delivery
– In a packet-switched network, no circuit is set
up prior to sending data between devices.
Blocks of data, even from the same file or
communication, may take any number of paths
as it journeys from one device to another.
Compare this to Figure 1 [circuit switching is
essentially a direct connection]

13. Not to be confused with Telnet
What is telnet?
– Telnet and its close cousins rlogin and
tn3270 are methods of connecting to a
remote computer over the Internet that
let you use programs and data just as if
you were using the computer locally. Do
not confuse telnet with Telenet, the old
name for Sprintnet.
– Telnet is a text-only protocol. At one
time it was one of the most common
ways to connect to other sites.
• Telnet FAQ © 2001 Walt Howe
(last updated 30 April 2001)

14. Significance of Telenet?
Published 1991

15. 1980s
Main uses scholarly or military
– Libraries use Telenet and Tymnet for
remote searching of databases
– Scientists and scholars communicate by
email
The Silent 700 was a line of portable
computer terminals manufactured by Texas
Instruments in the 1970s and 1980s. Silent
700s printed with a dot-matrix heating
element onto a roll of heat-sensitive paper.
They were equipped with an integrated
acoustic coupler and modem that could
receive data at 30 characters per second.

16. What, no fun things?
Enter the BBS!
– Bulletin Board System
– A forum for users to browse and exchange
information. Computer BBSs are accessible by
telephone via a personal computer and a
modem. Many BBSs are small operations run
by a single person that allow only several users
to log on at the same time. Some are much
larger and allow hundreds of users to login
simultaneously to use the system. Huge,
commercial examples are America Online,
CompuServe, and Prodigy.
• From Glossary of Distance Education and Internet
Terminology

17. BBS all text, very little graphics

18. Related to BBS
Gopher
– The Gopher Protocol is a distributed document
search and retrieval protocol that was
developed at the University of Minnesota in the
late 1980s. Resources are stored on Gopher
servers, which organize information using a
hierarchical directory structure. Gopher clients
access servers to retrieve directory listings of
available resources, which are presented to the
user as a menu from which an item may be
selected for retrieval.
• Gopher Protocol (Gopher) (Page 4 of 4)

19. A Gopher menu
Hong Kong Baptist University’s Home Gopher Menu
To navigate the menus, you used the arrow keys (no mouse, of course!) to
move the arrow up or down the menu and then hit Enter to select the item
you wanted. Current browsers no longer support Gopher.

20. Veronica, Jughead and Archie!
Rodent companions (note: no Betty)!
– Veronica: “Very Easy Rodent-Oriented Net-
wide Index to Computerized Archives”
– Jughead: “Jonzy’s Universal Gopher Hierarchy
Excavation and Display”
– Archie: a popular FTP [“File Transfer
Protocol”] search program of the time. Though
the legend of Archie being named for the
cartoon, the name in fact is shorthand for
“Archives.”
• A Pre-Web Search Engine, Gopher Turns Ten
By Chris Sherman, Search Engine Watch, Feb 6, 2002

21. The Web is added: 1991
Tim Berners-Lee:
– “. . . in 1989, while working at the European Particle
Physics Laboratory, I proposed that a global
hypertext space be created in which any network-
accessible information could be refered to by a single
“Universal Document Identifier”. Given the go-ahead
to experiment by my boss, Mike Sendall, I wrote in
1990 a program called “WorldWideWeb”, a point
and click hypertext editor which ran on the “NeXT”
machine. This, together with the first Web server, I
released to the High Energy Physics community at
first, and to the hypertext and NeXT communities in
the summer of 1991.”
• The World Wide Web: A very short personal history

22. The first “real” browser
NCSA Mosaic
In 1991, the NCSA introduced NCSA Mosaic, the
first readily-available
graphical Web Browser
that virtually kickstarted
the dot.com revolution. It
may not look like much
now - but it is interesting
to consider how similar
modern browsers look to
the original.
PawPrint.net Glossary of Terms

23. Today‟s browsers

24. Alphabet soup of the Web
URL
– Uniform Resource Locator
HTTP
– HyperText Transfer Protocol
HTML
– Hypertext Markup Language
– Now being complemented by XML
• EXtensible Markup Language
– See What is XML?

25. Basic URL Structure
Parts
– A URL has three basic parts: the protocol (how to get the resource);
the server id (who to get the resource from); and the resource id (the
name of the resource and how to find it on the target machine). In its
most basic form, this looks like the following:
– The "http" indicates that this is a Web document. The
"www.fake.com" is the domain name of the (in this case, fictional)
machine on which the web server is running (we know it’s a web
server because of the protocol). And, of course, “doc.html” is the
filename of the HTML document (notice the file extension “.html”)
on that machine.

26. Other url address types
Gopher URLs
– gopher://gumby.brain.headache.edu:151/7fonebook.txt
Access the searchable index “fonebook.txt” from the
named gopher server, running on port number 151.
[It’s unlikely that you will be access this: few modern browsers
support gopher any longer ]
Mailto URL
– mailto:user@host?subject=Happy%20lobsters
[Allows you to] include mail headers within the mailto
URL. [This] example [will] send a letter with the
subject line “Happy lobsters”.
• For other examples, see Uniform Resource Locators (URLs) from
Introduction to HTML by Ian Graham, The Information
Commons, University of Toronto. Last Update: 20 September 2000

27. Domain name?
What is a „Domain Name‟?
– Domain Name System, or DNS, is the most
recognized system for assigning addresses to
Internet web servers (aka “Internet hosts”).
Somewhat like international phone
numbers, the domain name system helps to give
every Internet server a memorable and easy-to-
spell address. Simultaneously, the domain
names keep the really technical IP address
invisible for most viewers.
• By Paul Gil, About.com Guide

28. Structure of a Domain Name 1
Top-level domain or first-level domain
– Every domain name has a suffix that indicates the
Top Level Domain (TLD) to which it belongs. The
TLD is the part of an internet domain name which
can be found to the right of the last point. Generic
TLDs include .com, .int, .net, .info, .org, etc. There
are also many country code top level domains
(ccTLDs) such as .es, .it, .cz and .be. Each TLD is
associated with a particular registry which
registers the names associated with the TLD.
• What is a Top Level Domain (TLD)?
• The .eu Top Level Domain

29. Structure of a Domain Name 2
Second-level domain
– In the Domain Name System (DNS)
hierarchy, it is the highest level
underneath the top-level domains. It is
that portion of the domain name that
appears immediately to the left of the
top-level domain, separated by a dot.
For example, the “NetLingo” in
www.netlingo.com is a second-level
domain.

30. Structure of a Domain Name 3
SubDomain - The Third Level Domain
– If you need to further distinguish your
second-level domain name, you can use a
third-level domain name, such as
“resources.hostway.com.” Typically a
third-level domain name is used to refer
to different servers within different
departments of a company.
• Creating third-level domains

31. Examples of 3rd level domains closer to
home?
From Murray State:
– http://campus.murraystate.edu
– http://lib.murraystate.edu/

32. Success of the web?
Tim Berners-Lee:
– The success of the World Wide Web, itself built on the open Internet, has
depended on three critical factors: 1) unlimited links from any part of the
Web to any other; 2) open technical standards as the basis for continued
growth of innovation applications; and 3) separation of network layers,
enabling independent innovation for network transport, routing and
information applications. Today these characteristics of the Web are easily
overlooked as obvious, self-maintaining, or just unimportant. All who use
the Web to publish or access information take it for granted that any Web
page on the planet will be accessible to anyone who has an Internet
connection, regardless whether it is over a dialup modem or a high speed
multi-megabit per second digital access line. The last decade has seen so
many new ecommerce startups, some of which have formed the foundations
of the new economy, that we now expect that the next blockbuster Web site
or the new homepage for your kid's local soccer team will just appear on
the Web without any difficulty.
• Testimony of Sir Timothy Berners-Lee, Hearing on the “Digital Future of the United
States: Part I -- The Future of the World Wide Web”

33. The internet a conversation?
 The Internet is a far more speech-enhancing
medium than print, the village green, or the
mails. . . . The Internet may fairly be regarded
as a never-ending worldwide conversation.[1]
Statement by a federal judge in American Civil
Liberties Union v. Reno, 929 F. Supp. 824, 844 (E.D. Pa. 1996)
(Dalzell, J.). Quoted by Tim Berners-Lee in his Testimony at
Hearing on the “Digital Future of the United States: Part I --
The Future of the World Wide Web”