So, let's talk a little bit about some of the details of the technology that you interact
with every day. Let's start with the Internet. The Internet was created by people. Where
did it come from? Well, originally it was funded by the Defense Department which is
a United States agency. It was funded and conceptualized and put out for bid by an organization
called The Advanced Research Projects Agency. ARPA is what the acronym is pronounced as.
It has since become something that is more familiar perhaps, DARPA, the Defense Advanced
Research Projects Agency. So, ARPA before DARPA was responsible for creating the Internet
for getting people together in order to build this thing that we call the Internet. The
key thing that was different about the Internet than from technology that came before it,
for example the telephone, was an innovation called packet switching. Prior to packet switching
we had something that was called circuit switching. If you are familiar with old videos or old
pictures of people, particularly telephone operators, putting wires into this big board
and trying to connect telephone calls... my mom actually had this job when she was growing
up. She was responsible for creating circuits between different people at different sides
of the world, and she would have to listen to phone calls in order to hear the people
that were on the phone who would ask her to make a connection to some other location on
the other side of the nation largely. So, she would plug in the wires to create a circuit
between two locations. So, if you made a telephone call you were actually communicating across
one long extended wire that was manually connected. So, what the Internet did is it enabled many
different conversations to be able to travel over one single wire by breaking up the conversation
into packets rather than requiring one separate circuit to create an end-to-end connection
between the people that wanted to communicate. That was the key innovation of ARPANET, and
it was what was the basis of the Internet that we know today. The Internet was initially
formed between four different locations, and this is a class in the University of California
and one thing that we don't talk very much about is how instrumental the University of
California was in the formation of the Internet. In fact, two of the first four nodes that
were on the Internet were University of California campuses. They were UCLA and UC Santa Barbara.
The other two nodes that were the first on ARPA's Internet were SOI which is up in Stanford
and the University of Utah. They used something called IMPs which are Interface Message Processors.
These were basically the first network cards, but they didn't sit inside a computer. They
were outside the computer. These IMPs connected these four locations and enabled the packets
to be switched between these different locations over one circuit. That first Internet message
was sent on October 10, 1969. It was sent by a UCLA student programmer named Charley
Kline about 10:30 at night. He transmitted that message from a computer called SDS Sigma
7, that was the host computer, and sent it to Stanford's Research Institute in a different
SDS computer. The attempt of that communication is shown here in the log. This is a paper
log that researchers were keeping track of to document their progress. The attempt was
to log into that computer. So, the language that they sent were the letter L for login,
and then the letter O, and immediately after they sent the O the computers crashed. So,
literally the first message that was sent on the Internet was L O, LO. Now, a couple
hours later they got the computers back online and they were able to successfully recover
from the crash and send a complete command, log in, and with that the Internet was born
with that one communication. So, that first link was in October of 1969. A permanent link
was established about a month later on the 21st of November. Then by December 5, 1969,
all four of those nodes had been connected in a permanent network that were sending packages
back and forth around this nation Internet, although we don't know how often it was crashing
after that. Now, in parallel something else was going on with the creation of the Internet.
There was something that was being created in Hawaii through the University of Hawaii
system called ALOHAnet. ALOHAnet was doing something slightly different. They were trying
to connect the Hawaiian Islands by radio. So, unlike land-based stations, Hawaii didn't
have the benefit of being able to be connected by wire. At that point they didn't have undersea
cables that were connecting the islands for this purpose, and so they were trying to do
the same thing, but they were trying to do it over radio networks. So, the key innovation
in ALOHAnet was allowing 7 different computers to use the medium. The medium in this case
was the radio frequency that they were using to communicate the message, and being able
to use all the computers to communicate at the same time, the same frequency, and still
be able to get their message through. This technology became the foundation for how mobile
phones when you talk on them are able to all use the same frequencies, and has since evolved
of course, but originally use the same frequencies in order to communicate even though all the
phones around you are using the same frequency. It also became the basis for Wi-Fi communication.
How computers connect to the Wi-Fi network owes its heritage to that which was developed
at the ALOHAnet. So, key milestones in the invention of the Internet were 1969 ARPAnet
sent the first message which was a landline-based system. In 1970 we're very sad, the first
e-mail was sent. Of course life has never been the same since. In 1971 in parallel the
first ALOHAnet demo was made. Then in 1972 ARPAnet and ALOHAnet came together and those
two were connected to form a joint network. By 1973 there were 40 nodes in the entire
ARPAnet network, so it was growing slowly but steadily and it included the first international
node which was located in Norway. 12 years later in 1985 the ARPAnet that was in existence
at that point got split into two separate networks. One was the military side of the
network, and the other was the civilian side of the network. The military side branched
off. The civilian side became what is known as NSFnet and became the civilian Internet.
That continued growing until 1995 at which point the backbone was transitioned to private
companies and the backbone being managed by commercial companies from then on. So, from
then the Internet has had a structure similar to what we see in 2014. This graphic here
just shows you in 1991 what the connections were in NSFnet, those white lines being the
backbone that were connecting major hubs like freeways connect cities if you drive by car,
and the vertical pink and yellow lines showing the smaller connections that would go from
these regional hubs down to local universities in the same way that arterial roads or residential
nodes connect houses with the freeway. The colors represent how much traffic was being
sent at that time. So, that is the origin of the Internet in a nutshell. What I think
would be important now is to talk about some other kinds of terminology that are going
to be talked about as we talk about information technology.