Thesis Statement:
Although it is a massive resource of
information, people from the university community who could profit from its
tremendous data bank fail to take advantage of it.
I. Preface
II. History of the Internet
III. Understanding how it works
A. Packets and Addresses
B. Usability
C. Domain Name
System
IV. Navigating Around
V. Finale
In the middle of the information age, our lives depend each day more and
more on communication. The way we communicate has evolved through the years
changing the methods in which information is produced and distributed. This
has made a notable influence on the way we receive and perceive information.
Information plays a vital role in the way we stay competent and therefore
in this ever demanding world, the need for exceedingly large amounts of
information is essential to our progress. This great need for information
has led to technological advances which have brought the world closer, making
long distances shorter, allowing us to travel to remote places faster and
virtually putting the whole world at our fingertips.
One of these technological advances has been the development of computer
networking. Networking is the method of connecting computers together in
a way in which they can work with each other and share information. The Internet
is an example of such a network and although it is a massive resource of
information, people from the university community who could profit from its
tremendous data bank fail to take advantage of it.
For those who do not know what is Internet, there really is no single definition
to what word means. One can refer to the Internet as a group of linked networks
that speak the same language (*TCP/IP protocol) or the group of people that
use hose networks or the collection of resources that can be reached from
those networks. There has never been one term agreed upon as to what the
Internet is. Being such a controversial term, the best way to understand
the Internet is by looking back at how it all started and follow its evolution
to what it currently portrays.
Internet started more than twenty years ago as an experiment, while the U.S.
Department of Defense was trying to connect together a network called the
**ARPAnet and some other radio and satellite stations. The objective of the
whole project was to build a communication system that would withstand
catastrophes and still be functional.
In the ARPAnet network model (see Appendix A), communication will always
occur between two computers: a source (the local terminal) and a destination
(the remote terminal). It was designed to require minimum information from
each end. To send a message through the network all one had to do was put
its data into an envelope called Internet Protocol (IP) packet and
switch it over to the destination with the correct "address".
*A protocol is a common method of communication
between parties or in this case computers.
**ARPA = Advanced Research Projects Agency
With this packet switching technique, the source and destination computers
were responsible for making sure that the packets got from one end to the
other. Since the network itself was supposed to be unreliable and any portion
of it could disappear without notice, the network was built around the idea
that each computer would be able to serve as a pier or levee with any other
computer. If for some reason some part of it were unavailable between the
source and destination computers, the machines would automatically trace
the next best route among the two and proceed to deliver the message. This
model of networking proved to be very reliable because it not only permitted
flawless connections but it also provided the only practical method for computers
from different manufacturers to communicate. This was a very attractive idea
for universities and other large institutions which did not own one standard
set of computers. They could all use whichever computer they preferred and
could still work over the network, sharing data files, programs or electronic
mail.
As technology evolved and computer prices dropped, manufacturers started
to put TCP/IP protocol into their machines. It was not too long before research
institutions, libraries and large corporations started adopting the protocol
to connect their computers together. This new demand started a communication
standard that all institutions took benefit of. Since then, the Internet
has not stopped growing. It is the fastest growing system of human communication
in history. It has grown faster than telephone, television or fax. It currently
connects over 10,000,000 computers, more than 20,000,000 users and grows
25% each month1.
To understand how Internet works, it is convenient to state a comparison
between Internet and some other packet switched network. The postal service
is a good example of a packet switched network.
Here, one does not have a dedicated piece of the network. What ever is going
to be sent gets packed up with everybody else's things, put in a bag, transferred
to the next Post Office and finally sorted out again.
One never has a direct route to your destination reserved for your data.
The postal office decides how it is going to pack that data and send it to
the next substation. Until the data reaches its destination, the whole process
will be repeated from substation to substation.
Like the postal service, the Internet has a set of substations called routers.
Routers are the computers in charge of sorting out all the data that moves
through the network and sends it to other routers until the final destination
is reached 2.
In order for the routers to know to which specific computer in the network
the data is heading, it is necessary to assign a unique address to each computer
on the network. Just like the postal service the data is put into an envelope,
addressed and sent. The envelope in this case being a packet and the address
(IP address) consisting of four sets of numbers smaller than 256 and separated
by periods (154.217.56.21). The packets are small chunks of information not
exceeding 1500 characters in longitude. Once data exceeds 1500 characters
it is necessary to place the data in another packet and address it to the
same destination as the first. In order to make sure that multiple packets
get pasted the way they should on the destination compute; the Transmission
Control Protocol (TCP) gives a number to each of the packets to assure that
they are all pasted back in proper order on the destination computer. If
for some reason any of the packets get lost or do not arrive, it asks the
sending machine to retransmit/hem. TCP also has the power of detecting any
errors in any of the packets and correcting them before pasting any more
packets.
Although it all sounds very difficult, its actually extremely easy to get
things from one place to the other. Considering that most of the work is
done by the computers, all one really has to do is fill in the names. Through
time vendors have developed software which automate the most common tasks
and allow the user to concentrate on what needs to be done rather than on
how to do it.
To make things even easier, another way of addressing computers was developed,
putting names over the numbers. This naming process was called The Domain
Name System. Its structure assigns names to the IP address numbers and separates
them with periods: inter.ui.clu.edu.
Each name represents a domain with a certain level. The higher to the right,
the higher the level (see Appendix B).
There can be any number of domains within a address, but in most cases there
will be five or less. This naming system does not replace the IP address
but only works on top of it making the process of addressing computers
easier.
When the computer sees the address
inter.ui.clu.edu, it proceeds to convert
each domain name to an IP address. In order for the computer to link a domain
name with an IP address, the name must be part of a worldwide database in
which the computer will look it up. This database is located at the root
computer which is the one et the highest domain or level (in this case
edu). Once the source contacts this computer,
it asks for the address of the computer at the next domain
(clu). It then proceeds to contact
clu and asks for the
address of the computer at the next domain
(ui). This procedure is the repeated
until then last domain is reached (inter).
Once the outermost domain is reached, connection will be established. The
user in the source computer can then proceed to work with the remote computer.
In order to work more efficiently, Internet offers, some special tools that
allows him to navigate around, making the journey easier. The most commonly
used tools are telnet and
ftp.
Telnet is used for logging into other computers across the
network3. When connection is established, the source computer
acts as if it were locally connected with the destination and is able to
access the same information that can be accessed through a computer that
is locally connected. This is the tool to use when connecting to public services
and databases available all over the network.
FTP is used for moving files between computers4. Like telnet,
the user can access public databases across the network with the difference
that he can transfer any file he needs down to his terminal.
These two basic tools, are all the user needs to make a successful Internet
connection. In a place where the concept of time and distance as we know
it is redefined, it is hard to predict what you'll find. Being the Internet
one undivided network, there are practically no frontiers.
Through the net, a computer that is physically thousands of miles away is
just as close as a computer in the office next door. This means that any
information that is available thousands of miles away is as near and available
as if it were right next door. This is one of the most significant advantages
of the network. One's computer does not need to be anywhere near the computer
one wants to access to use the same services available to a computer that
is.
All this adds up to say that any person using Internet can have the same
access to any computer on the net as if he were physically on the other computer,
no matter how far away it is. Once inside, the possibilities are endless.
Best of all, a lot of the information found on the network is in the public
domain and therefor free for the taking.
Even with all these advantages, not too many people in the university community
benefit from Internet. Many do not even know it exists. This is due largely
to the fact that many people still think that computers are difficult to
learn and use. Hopefully some time in the future, people will start looking
into Internet and will then unleash the true potential that lies within it.
Each computer is represented by a dot and connected by a line. If a connection
were to be unavailable between two computers, the routers are capable of
finding another path between the two points.
In the address above, inter is the domain
name of a computer. This computer named
inter is maintained by
ui which is the main computer in a
university. The university computer
ui is part of a network named
clu. This network named
clu is part of a national group of
educational institutions which classify to the domain name
edu.
1 Tracy L. LaQuey, User's Directory of Computer
Networks
(Bebford, MA: DigitalPress, 1989) 57.
2 Ed Krol, The Whole Internet: User's Guide &
Catalog
(Sebastopol, CA: O'Reilly & Associates, 1992) 38.
3 Krol 67.
4 Krol 69.
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nic.ddn.mil, directory: rfc, filename: rfc1175.txt]
Krol, Ed. The Hitchhiker's Guide the to Internet.
Network Working Group, Request for Comments 1118, September, 1989.
[Available via anonymous FTP on host: nic.ddn.mil, directory: rfc, filename:
rfc 1118.txt]
Krol, Ed. The Whole Internet: User's Guide & Catalog,
Sebastopol, CA: O'Reilly & Associates, 1992.
Krol, Ed. and E. Hoffman. FYI on "What is the
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Network Working Group, Request for Comments 1462, May 1993.
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Ladner, Sharyn J. and Hope N. Tillman. "Getting on the Internet."
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LaQuey, Tracy L. User's Directory of Computer Networks.
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