1. The History of the Internet

2. Three Major Players in Internet History

3. Early Innovations
The creation of the Internet is dependent on mankind’s earlier innovations
Telegraph by Cooke and Wheatstone
Revolutionized human (tele)communications.
Morse Code a series of dots and dashes used to communicate between humans. This is similar to how computers communicate via (binary 0/1) data today. Although it is much slower!!
Transatlantic cable. Allowed direct instantaneous communication across the Atlantic. (Cyrus Field) Today, cables connect all continents and are still a main hub of telecommunications.
Telephone. Alexander Graham Bell Exhibits.
Telephones exchanges provide the backbone of Internet connections today.
Modems provide Digital to Audio conversions to allow computers to connect over the telephone network.

4. Political Events 1940’s to 1980’s - U.S. vs. Soviet Cold War
U.S.S.R. launches Sputnik. The US forms the Advanced Research Projects Agency (ARPA) within the Department of Defense (DoD) to build US skills in computer technology.
The start of global telecommunications. Satellites play an important role in transmitting all sorts of data today.

5. ARPA Created
In response, US forms the Advanced Research Projects Agency (ARPA) within the Department of Defense (DoD) to establish US lead in science and technology applicable to the military.
Dr. J.C.R. Licklider (‘Lick’) was chosen to head ARPA's research in improving the military's use of computer technology.
Licklider was a visionary who sought to make the government's use of computers more interactive.
Moved ARPA's contracts from the private sector to universities and laid the foundations for what would become the ARPANET.

6. Packet-Switching is Key
Packet-switching (PS) networks developed
The Internet relies on packets to transfer data.
Data is split into tiny packets that may take different routes to a destination. (vs. circuit switching)
The origin is military : for utmost security in transferring information of networks (no single outage point).
More than one route available -- if one route goes down another may be followed.
Networks can withstand large scale destruction (Nuclear attack - This was the time of the Cold War).

7. The Story of ARPANET - Team
ARPANET commissioned by DoD for research into networking. The Team included:
Bob Taylor, a psychoacoustician, was director of the computer research program at the Department of Defense's Advanced Research Projects Agency in 1966 when he hit upon the idea of lining computers together. He was awarded $1 Million to develop the network.
Larry Roberts, a pioneer in computer networking at MIT's Lincoln Laboratory. He designed the original four-node network, which was to be based on packet-switching, as opposed to circuit-switching.

8. The Story of ARPANET – the Nodes
1969 – Four nodes and a test
First node at UCLA
soon after at:
Stanford Research Institute (SRI)
UCSB
U of Utah
                                                                                                              

9. The Story of ARPANET – The IMPs
1969 – To connect these four computers – each with its own “language” – Wes Clark suggested to Larry Roberts that 4 small computers that spoke the same language be constructed and connected together.
The small computers were called Information Message Processors (IMP) [Honeywell 516 mini computer with 12K of memory] developed by Bolt Beranek and Newman, Inc. (BBN)

10. The Birth of the Internet
The plan was unprecedented: Leonard Kleinrock, a pioneering computer science professor at UCLA, and his small group of graduate students hoped to log onto the Stanford computer and try to send it some data.
Vinton Cerf
develop TCP/IP
Steve Crocker
developed ARPANET network protocol
Mike Wingfield
Wingfield built the hardware interface between the UCLA computer and the first IMP
Jon Postel
developed Domain Name System, FTP, Telnet, and the Internet Protocol.
Bill Naylor

11. The Birth of the Internet
They would start by typing "login," and seeing if the letters appeared on the far-off monitor.
Kleinrock : "We set up a telephone connection between us and the guys at SRI...,"
"We typed the L and we asked on the phone,
"Do you see the L?"
"Yes, we see the L," came the response.
"We typed the O, and we asked, "Do you see the O."
"Yes, we see the O."
"Then we typed the G, and the system crashed"...
Yet a revolution had began"...
Source: Sacramento Bee, May 1, 1996, p.D1
LOG

12. The Birth of the Internet
Ray Tomlinson of BBN invents program to send messages across a distributed network. The original program was derived from two others:
an intra-machine program (SNDMSG) and an experimental file
transfer program (CPYNET)
15 nodes (23 hosts) on ARPANET.
The first message??
qwertyuiop

13. The Birth of the Internet
Global Networking becomes a reality
First international connections to the ARPANET: University College of London (England) and Royal Radar Establishment (Norway)
Packets become mode of transfer
Transmission Control Program (TCP) specified. Packet network Intercommunication -- the basis of Internet Communication.
Telenet, a commercial version of ARPANET, opened -- the first public packet data service.
Networking comes to many
Queen Elizabeth sends out an .

14. The Birth of the Internet
takes off, Internet becomes a reality
Number of hosts breaks 100.
THEORYNET provides electronic mail to over 100 researchers in computer science (using a locally developed system and TELENET for access to server).
News Groups born
Computer Science Department research computer network established in USA.
USENET established using UUCP.
A collection of discussions groups, news groups.
3 news groups established by the end of the year
Almost any topic now has a discussion group.

15. The Birth of the Internet
News Groups born
Computer Science Department research computer network established in USA.
USENET established using UUCP.
USENET still thrives today.
A collection of discussions groups, news groups.
3 news groups established by the end of the year
Almost any topic now has a discussion group.

16. The Birth of the Internet
TCP/IP defines future communication •DCA and ARPA establishes the Transmission Control Protocol (TCP) and Internet Protocol (IP), as the protocol suite, commonly known as TCP/IP, for ARPANET.
Leads to one of the first definitions of an Internet as a connected set of networks, specifically those using TCP/IP.
Internet gets larger
Name server developed.
There is such a large number of nodes that its hard to remember exact paths
Use meaningful names instead.

17. The Birth of the Internet
Growth of Internet Continues
Number of hosts breaks 1,000.
Domain Name Server (DNS) introduced. Instead of it is easier to remember something like
( e.g.
Power of Internet Realized
5, 000 Hosts. 241 News groups.
NSFNET created when NSF establishes 5 super-computing centers to provide high-computing power for all -- This allows an explosion of connections, especially from universities.

18. The Birth of the Internet
Commercialization of Internet Born
Number of hosts 28,000.
UUNET is founded with Usenix funds to provide commercial UUCP and Usenet access.
1988
Internet Relay Chat (IRC) developed
Large growth in Internet
Number of hosts breaks 100,000
First relays between a commercial electronic mail carrier and the Internet

19. The Birth of the Internet
English scientist Tim Berners-Lee invented the World Wide Web in 1989.
He wrote the first web browser computer program in 1990 while employed at CERN in Switzerland.
This ‘GUI’ drastically changed access to the Internet.

20. The Birth of the Internet
Expansion of Internet continues
300,000 Hosts. 1,000 News groups
ARPANET ceases to exist
Archie released files can be searched and retrieved (FTP) by name.
The World comes on-line (world.std.com), becoming the first commercial provider of Internet dial-up access.

21. The Birth of the Internet
Friendly User Interface to Internet established
Gopher released by Paul Lindner and Mark P. McCahill from the U of Minnesota.
Text based, menu-driven interface to access internet resources.
No need to remember or even know complex computer command. User Friendly Interface (?).
Largely superseded by WWW, these days.

22. The Birth of the Internet
Multimedia changes the face of the Internet
Number of hosts breaks 1 Million. News groups 4,000
The term "Surfing the Internet" is coined by Jean Armour Polly.

23. The Birth of the Internet
The WWW Revolution truly begins
Number of Hosts 2 Million. 600 WWW sites.
The Mosaic Web browser is released (by a group of 10 students from U of I at Champaign-Urbana) on the Net, gaining 2 million and fueling a 341,634% annual growth rate for Web traffic.

24. The Birth of the Internet
The WWW Revolution truly begins
The White House opens its Web page and the President gets an address.
Business and Media really take notice of the Internet.
Mosaic takes the Internet by storm.
User Friendly Graphical Front End to the World Wide Web.
Develops into Netscape -- most popular WWW browser to date.

25. Internet, Packets and Routing
The Internet is a network of computer networks
Data is transmitted by packet switching using the standard Internet Protocol (IP)
Packet – a unit of information carriage
Packet switching – process of moving packets from one node (computer device) to another

26. A Visualization of Internet

27. Internet, Packets and Routing
At the sender, data is broken into packets and sent to the nearest node (router)
At each router, it sends the packet to another router that is closer to the final destination
At the receiver, packets are reassembled to get the original data
A comparison: mailing system

28. Mailing System A B
A&M-Commerce
UTA
Admin

29. TCP/IP and Domain Names
Basic task of IP – moving packets as quickly as possible from one router to another
Yet, it doesn’t check whether packets are delivered successfully, thus it needs TCP
TCP (Transmission Control Protocol) – disassemble/reassemble packets, error checking, ACK packets

30. TCP/IP and Domain Names
TCP's relatively complex protocol called the "three-way handshake”
SYN
SYN/ACK
ACK
The protocol is based on:
SYN - (Synchronize) Initiates a connection
FIN(Final) Cleanly terminates connection
ACK - Acknowledges received data

31. TCP/IP and Domain Names
We need some sort of address in order to identify different nodes, as every house has a mailing address in order to receive mail from others
The one used by Internet Protocol is called IP address
Every host on the Internet has a unique IP address, made up of four numbers. E.g , each number was originally between 0 and 255

32. TCP/IP and Domain Names
Every host on the Internet has a unique IP address, made up of four numbers. E.g , each number was originally between 0 and 255
IP Version 6 (IPv6) adds more options

33. Why?
If you know binary, you will understand that each of these numbers are stored in 8 bits (binary digits), and the number of possibilities you can have is 2 raised to the power of 8, which is 256 (0-255).

34. TCP/IP and Domain Names
The numbers in an IP address are hard to remember, names are easier
Domain Name System – a mapping between the human-readable name (domain name) of a host and its IP address
A domain name consists of two or more parts, e.g. hssa.tamuc.edu
The rightmost label conveys the top-level domain, e.g. edu

35. TCP/IP and Domain Names
The Internet Corporation for Assigned Names and Numbers manages the top-level development and architecture of the Internet domain name space.
ICANN authorizes domain name registrars, through which domain names are registered and reassigned.
Domain name registration with a registrar does not confer any legal ownership of the domain name, only an exclusive right of use.

36. TCP/IP and Domain Names
Each label to the left specifies a domain, in our example, domain is now tamuc (University’s registered domain name), then sub-subdomain is hssa (Humanities Social Sciences Arts).
A top-level domain can contain multiple subdomains, each subdomain can contain multiple sub-subdomains, so on.
The database contains the mapping between a domain name and an IP address is stored on a DNS server.

37. World Wide Web
The World Wide Web (commonly shortened to the Web) is a system of interlinked, hypertext documents accessed via the Internet.
It is created to share files/documents and overcome the barrier of different file formats
Hypertext refers to text on a computer that will lead the user to other, related information on demand.

38. World Wide Web
Hypertext documents are created using a special kind of document formatting or “markup” language called HyperText Markup Language (HTML).
Not computer code
HTML is sent or received over the network using HyperText Transfer Protocol (HTTP).
A browser is a software program which interprets the HTML documents and displays it on the user’s screen.

39. URLs and Client-Server Model
Each document/resource on the WWW needs to have an identifier in order to be accessed by others.
A Uniform Resource Identifier (URI), is a compact string of characters used to identify or name a resource.
A Uniform Resource Locator (URL) is a URI which provides means of obtaining the resource by describing its network “location”.

40. URLs and Client-Server Model
Two things are given by the URL
Exact location of the document
The method or protocol by which to retrieve and display the document
Example,
– specifies the protocol
faculty.tamuc.edu – specifies the subdomain / host name / domain name
/TDeMars/151outlineF17.html – specifies the path of the document on the host

41. Registrars GoDaddy Mad Dog – login
nearly 3,000 accredited domain name registrars in the market
‘Top 9’
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