The document provides a history of the development of the Internet from its origins as the ARPANET network in the 1960s through its evolution and commercialization in the 1990s. It describes how ARPANET was developed by the US Department of Defense to connect researchers and universities. In the 1970s and 80s, ARPANET expanded significantly and adopted the TCP/IP protocol. By the 1990s, the NSFNet backbone and connections to commercial networks transformed ARPANET into the modern Internet. The development of the World Wide Web in the early 1990s, enabled by browsers, further drove the widespread adoption and commercialization of the Internet.

1. Internet History and Growth

2. What Is the Internet?
• A network of networks, joining many government,
university and private computers together and
providing an infrastructure for the use of E-mail,
bulletin boards, file archives, hypertext documents,
databases and other computational resources
• The vast collection of computer networks which
form and act as a single huge network for transport
of data and messages across distances which can be
anywhere from the same office to anywhere in the
world.
Written by William F. Slater, III
1996
President of the Chicago Chapter of the Internet Society

3. What is the Internet?
• The largest network of networks in the
world.
• Uses TCP/IP protocols and packet switching .
• Runs on any communications substrate.
From Dr. Vinton Cerf,
Co-Creator of TCP/IP

4. ARPANET
• In 1968, the Defense Department began
developing ARPANET
ARPA – Advanced Research Projects Agency
• WAN (wide area network) designed to
connect DoD researchers and university
researchers
• Development of WANS, routers and the
Internet Protocols
• used packet-switching

5. ARPANET
– ARPANET went on line in 1969 connecting 4
computers in California and Utah
• In 1972, Email was invented
• In 1973, APRANET went international with
sites in England and Norway
• The ARPRANET grew rapidly in the 1980s:
– By 1981: 213 computers
– By 1984: 1000 computers
– By 1987: 10000 computers

6. From APRANET to INTERNET
• In 1982, the military portion of the
ARPANET was separated into MILNET
• Supervision of ARPANET was passed to
the NSF (the National Science
Foundation)
• In 1983, the new TCP/IP protocol was
added

7. From APRANET to INTERNET
• By 1990, the original ARPANET
backbone was decommissioned in favor
of newer long-distance data
transmission networks
– The collection of NSF-sponsored
backbones and the regional sites it
connected together became the Internet

8. From Internet to WWW
• By the early 1990s, the Internet was primarily
used to connect Universities together
– Other commercial WANs began to connect to
the Internet
• Genie, CompuServe, Prodigy, etc
– Popular applications were Email, FTP

9. From Internet to WWW
– In 1994, a graphical Internet browser was
developed to allow easy access to materials
stored on the Internet
• the first web browser was called Mosaic
– This gave birth to the World Wide Web, the
collection of interlinked files on the Internet
• which has led to full-scale exploitation of the
Internet for global communications

10. Commercialization of the
Internet
• Before 1995 commercial traffic was
forbidden on the taxpayer-funded NSF
• In 1995 when NSF eliminated all
Internet subsidies commercial Internet
development took off.

11. The
Internet
Today
Areas of the world and
The number of computers
Part of the Internet
backbone

12. Who Controls the Internet?
• No one
• The Internet is made up of privately owned
computers and networks, all of which agree
to implement the Internet protocols.

13. Who Controls the Internet?
• Some organizations control certain aspects
of the Internet
– W3C, World Wide Web Consortium issues
standards related to all aspects of the Web.
• The Internet is everywhere and yet it is not
in any one location.
– In fact, the Internet was designed to survive a
nuclear war

14. Brief History of the Internet
• 1968 - DARPA (Defense Advanced Research Projects Agency)
contracts with BBN (Bolt, Beranek & Newman) to create
ARPAnet
• 1970 - First five nodes:
– UCLA
– Stanford
– UC Santa Barbara
– U of Utah, and
• 1974 - TCP specification by Vint Cerf
• 1984 – On January 1, the Internet with its 1000 hosts
converts en masse to using TCP/IP for its messaging

15. *** Internet History ***

16. A Brief Summary of the
Evolution of the Internet Mosaic
Age of
eCommerce
Begins
WWW Created 1995
Internet Created 1993
Named 1989
and
Goes
TCP/IP TCP/IP
Created 1984
ARPANET 1972
1969
Hypertext
Invented
Packet 1965
Switching
First Vast Invented
Computer 1964
Network
Silicon Envisioned
A Chip 1962
Mathematical 1958
Theory of
Memex Communication
Conceived 1948
1945
1945 1995

17. From Simple, But Significant Ideas Bigger Ones Grow
1940s to 1969
We will prove that packet switching
works over a WAN.
Hypertext can be used to allow
rapid access to text data
Packet switching can be used to
send digitized data though
computer networks
We can accomplish a lot by having a
vast network of computers to use for
accessing information and exchanging ideas
We can do it cheaply by using
Digital circuits etched in silicon.
We do it reliably with “bits”,
sending and receiving data
We can access
information using
electronic computers
1945 1969

18. From Simple, But Significant Ideas Bigger Ones Grow
1970s to 1995
Great efficiencies can be accomplished if we use
The Internet and the World Wide Web to conduct business.
The World Wide Web is easier to use if we have a browser that
To browser web pages, running in a graphical user interface context.
Computers connected via the Internet can be used
more easily if hypertext links are enabled using HTML
and URLs: it’s called World Wide Web
The ARPANET needs to convert to
a standard protocol and be renamed to
The Internet
We need a protocol for Efficient
and Reliable transmission of
Packets over a WAN: TCP/IP
Ideas from
1940s to 1969
1970 1995

19. The Creation of the Internet
• The creation of the Internet solved the following
challenges:
– Basically inventing digital networking as we know it
– Survivability of an infrastructure to send / receive high-speed
electronic messages
– Reliability of computer messaging

20. IPAddresses
IP – Internet Protocol
• an IP address is a 32-bit number
• NKU‟s web server has the IP 192.122.237.7
• routers throughout the Internet relay
messages from one location to another using
the IP address of the intended recipient

21. Internet Addresses and Aliases
• Its hard to remember these long numbers
• We give our machines “aliases” instead
– NKU‟s web server is known as sappho.nku.edu (or
www.nku.edu)
• We use aliases for convenience, it is
necessary to convert from an alias to an IP
address when sending a datagram
– Domain Name Servers (DNS) are tables stored on
various computers on the Internet that do this
conversion for us

22. The World Wide Web
• Many refer to the Internet today as the Web,
or the world wide web (www)
– In fact, the WWW is an application that runs on
the Internet
• It has a collection of files stored on certain computers
on the Internet known as web servers
– What makes it a web?
• Links

23. The World Wide Web
– In a Web page, there are links to other files
• Links are commands that tell a computer to go out
and retrieve another file over the Internet
• But unlike older Internet technologies where the user
had to know the IP address, the link contains the
address so there is nothing to memorize
• Click on a link  your computer sends a message
across the Internet requesting the specified document
(web page) referenced in the link
– the receiving computer sends the page back and your
computer loads it and displays it in your browser

24. URLs
• A link includes the location of the document being
referenced
– These links are called URLs
• Uniform Resource Locators
– URLs have four parts:
• Protocol (http, ftp) : //
– the protocol determines what will be done with the document
when it is received, http: display in a browser, ftp: save to disk
• Server - the web server storing the document you want
• Path - the directory where the document is stored
• Document (file) name
– Example: http://www.nku.edu/~foxr/CSC150/ch1.ppt
– NOTE: just because there is a link, doesn‟t mean it has
the right address – the address may be old, the file may
be gone, this leads to broken links (or dead links)

25. Web Browsers and Web Servers
• Web servers
– Computers that store web pages and allow client
computers to access them
• Web browsers
– allow clients to access web server
• If you have web pages on your computer but no web
server, no one can see those pages (outside of you)
• A web site is a collection of web documents
available on a computer running the web
server software
– The home page (or index page) is the main page,
the first one retrieved

26. Accessing a Web Page
3. Your request NATIONAL 4. Your request
goes to a goes to a national
network access backbone network.
point (NAP).
1. You request R
a Web page. E
G
I
O
N
A
L 5. Your request
2. Your request reaches the Web
YOU ARE site’s server and the
goes to your
HERE ISP’s point of Web page is sent
presence (POP). back to you in
packets.

27. Internet Computer in scramento
Requests information from
Communications: A computer in Savannah
1) Message packaged
A Variety of 2)
3)
Message sent by MODEM
To Internet POP
Technologies 4) To another component of
the Internet backbone via
microwave
5) To satellite
6) To receiving station in NY
7) By microwave to another
station in Atlanta
8) By phone to Georgia State
9) Where the message is
received by destination
machine

28. Configuring Your Computer
• What you need to get to the Internet:
– TCP/IP (which is available in the OSs)
– Communications equipment to connect your computer
to a network:
• A physical connection to the Internet
– Dialup access : modem
– DSL, Cable or Satellite access
• Access the Internet through your signal provider using a special
modem over the line to your house (coaxial, satellite dish or
DSL line)
– LAN access
• such as from NKU – access via LAN is usually much better than
through an ISP because of the use of T1 or better connections
• Network card

29. Interoperability
• The Internet is made up of many different
– Types of computers (IBM PC, Mac, mainframes, Unix
workstations, etc)
– OSs (windows, Mac OS, Unix, Linux, VMX)
– LANs (Ethernets, Appletalk networks, etc)
• This makes the Internet a cross-platform network
• All of these computers must be Interoperable
– they must speak the “same language”
– in this case, the language is the TCP/IP protocol
• Transmission Control Protocol/Internet Protocol
– IP protocol dictates how addresses and routers work
– TCP: reliable delivery, congestion control, service requested

30. Internet: Packet Switching Network
Messages are divided
into units called
packets
Each packet is given
a copy of the
destination address
and sent on its way
Each packet finds its
way independently
across the network
Upon receipt, the
receiving computer
assembles the
packets in order
before displaying
the message to the user

31. Packet Switching Continued

32. Intranets
• Because of the success of TCP/IP, many networks are
being configured today to use TCP/IP
– But rather than being a part of the Internet, they only
connect local computers together
– Thus, the organization has the same abilities as Internet
users (email, ftp, messaging, etc) but communication
remains local
• A firewall might be placed between a company‟s Intranet and
the Internet so that critical information can not be sent out and
viruses and other harmful attacks can not make their way in
• The firewall is special software running on a computer that acts
as the point of contact (or connection) to the Internet
– An Extranet is an Intranet
that is open to certain pre-
specified users, so in a way,
its like opening up your
network to only a portion of
the Internet but where you
dictate who gains access

33. Who Do You Trust?
• The Web is a great source of information. One
problem is that there are no rules about what
people can say on their web sites
– Inaccurate information
– Irrelevant information
– Out-of-date information
• In examining information, keep in mind
– who the author is
– whose server it is
– who the author‟s source is
– keep in mind accuracy and currency (date) of data
• the web is littered with web pages that haven‟t been updated
in years!

34. The Future of the Internet
• A billion Internet users by 2010?
– Can the IP protocol support this? No
• There are about 4 billion unique IP addresses
available but there will not be enough to go around
Class Network Machine
Addresses Addresses There are not enough Class B addresses
for all of the networks and many networks
Class A 127 16 million
that currently exist are outgrowing their
Class B 16,000 65,000 Class C addresses
Class C 2 million 254
• A newer version of IP addresses is being considered
called IPv6 – 128 bit address

35. Future of the Internet
– We will also have a problem supporting the need
for super-fast connections to transfer large data
files
• such as music and movies
• I2 (Internet 2)
– a project for developing gigaPop
– gigaPop: a gigiabit per second point of presence
– access to a backbone service capable of
transferring in excess of 1 Gbps.

36. Internet Growth Trends

37. Internet Growth Trends
• 1977: 111 hosts on Internet
• 1981: 213 hosts
• 1983: 562 hosts
• 1984: 1,000 hosts
• 1986: 5,000 hosts
• 1987: 10,000 hosts
• 1989: 100,000 hosts
• 1992: 1,000,000 hosts
• 2001: 150 – 175 million hosts
• 2002: over 200 million hosts
• By 2010, about 80% of the planet will be on the Internet

38. No. of Participating Hosts
Oct. „90 - Apr. „98

39. Having Internet Connectivity
• To have complete Internet connectivity you
must be able to reach all destinations on the
net.
• Your packets have to get delivered to every
destination. This is easy (default routes).
• Packets from everywhere else have to “find
you”. This is done by having your ISP(s)
advertise routes for you.

40. Internet service provider
(ISP or IAP)
ISP is a business or organization that
provides consumers or businesses access to
the Internet and related services. In the
past, most ISPs were run by the phone
companies. Now, ISPs can be started by just
about any individual or group with sufficient
money and expertise. In addition to Internet
access via various technologies such as dial-
up and DSL, they may provide a combination
of services including Internet transit, domain
name registration and hosting, web hosting.

41. ISP connection options
Typical home user connection
• Dial-up
• DSL
• Broadband wireless access
• Cable modem
• ISDN

42. ISP connection options
Typical business connection
• DSL
• SHDSL
• Ethernet technologies

43. DSL - Digital Subscriber Line
DSL is one of the most prevalent forms
of Internet connection. DSL provides
high-speed networking over ordinary
phone lines using digital modems. DSL
connection sharing can be easily
achieved with either wired or wireless
broadband routers.

44. Cable - Cable Modem Internet
Cable modem is a form of broadband
Internet connection. Cable Internet
uses neighborhood cable television
conduits rather than telephone lines,
but the same broadband routers that
share DSL Internet connections also
work with cable.

45. Dial Up Internet
Dial up uses ordinary telephone lines
but, unlike DSL, dial up connections
take over the wire, preventing
simultaneous voice calls. Dial up
routers are difficult to find, expensive,
and generally do not perform well
given such a slow Internet pipe. Dial up
is most commonly utilized in lightly
populated areas where cable and DSL
Internet services are unavailable

46. ISDN - Integrated Services
Digital Network
ISDN works over telephone lines and
like DSL, supports simultaneous voice
and data traffic. Additionally, ISDN
provides 2 to 3 times the performance
of most dial up connections. Home
networking with ISDN works similarly to
networking with dial up.

47. Satellite Internet
Enterprises like Starband, Direcway
and Wildblue offer satellite Internet
service. With an exterior-mounted
mini-dish and a proprietary digital
modem inside the home, Internet
connections can be established over a
satellite link similar to satellite
television services.

49. POP(Point of presence)
An Internet point of presence is an access point
to the Internet. It is a physical location that
houses servers, routers, ATM switches and
digital/analog call aggregators. It may be either
part of the facilities of a telecommunications
provider that the Internet service provider (ISP)
rents or a location separate from the
telecommunications provider. ISPs typically have
multiple POPs, sometimes numbering in the
thousands. POPs are also located in Internet
exchange points and collocation centres.

50. Internet POP Design
• Point of Presence (POP)
– An access point to the Internet
– A router is required to interface with the
service provider
– Demarcation point is where the ISP company
ends and the private network of the
customer begins.