Download Internet Standards and Protocols

Running Head: THE INTERNET
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The Internet
A Really Brief Summary of the History of the Internet, Protocols
And Applications That Evolved as Part of the ARPANET Program.
Michael Davis
University of Mobile
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History
There are any number of opinions of how the Internet started and like anything
else, the issue is one that has been argued repeatedly. Some will point out that packet
switching was proposed in some other part of the world and that would be the
beginnings of the Internet. Others will tell you that the Defense Advanced Research
Projects Agency (ARPA), was the real start. Like so much other technology, a case can
also be made that the Internet is the product of the space race. On October 4, 1957,
Russia launched Sputnik, which was man’s first attempt at the exploration of space. It
also caused the United States to aggressively begin a military campaign to compete
with the Soviets. This was when ARPA was created. It was to be the United States’
research agency for space and missile research. (DARPA and ARPA are just different
names for the same agency.)
This report will support the ARPA beginnings view. In particular, it will suggest
that it all really began with J.C.R. Licklider of the Massachusetts Institute of Technology
(MIT), who was the first head of the Information Processing Techniques Office (IPTO) at
ARPA (Waldrop, 2008). Licklider was talking about a symbiosis of men and machines
as early as 1958. In 1960 he wrote “Man-Computer Symbiosis”, which described some
of his ideas and once he became involved with ARPA, he was able to move forward
with them. It is interesting to find the number of times during a study of the history of
the computer that the same names of influential pioneers come up. In this case, we
learn that Licklider influenced people like Ivan Sutherland, the man considered to be the
Father of Graphic Design, and Doug Inglebart, the inventor of the computer mouse. In
fact, Sutherland replaced Licklider at IPTO, when Licklider returned to MIT. Licklider
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convinced those that followed him at ARPA of the importance of the network. He wrote
a series of memos in August of 1962 (Leiner, B. M., Cerf, V. G., Clark, D. D., Kahn, R.
E., Kleinrock, L., Lynch, D. C., Postel, J., Roberts, L. G., & Wolff, S., 2013). In them he
described a global network through which people could access data and programs from
anywhere. He referred to it as an “intergalactic network”. Ivan Sutherland was followed
at ARPA by Bob Taylor, who was in charge of the same department from 1966 – 1969
(Inductees, 2013).
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One of ARPA’s goals was to connect mainframe computers at different
universities, so that they could share
information even during network failures
caused by enemy attacks, or other
catastrophes such as the hurricanes that
those on the American gulf coast know so
well. According to one source, in 1965
another scientist from MIT developed packet
switching, which is a way of breaking
messages into pieces called packets that can
be sent from a source to a destination along
different routes (The Invention of the Internet,
FIGURE 1
2013). At MIT, Leonard Kleinrock published
a paper on packet switching theory in 1961
and Lawrence G. Roberts and Thomas Merrill actually made an interstate connection of
computers swapping packets of data over a telephone line (Inventor of the Week,
2000). The result was the creation of ARPANET in 1969 (The Birth of the Internet,
2013). ”In fall 1969, the first such node was installed in UCLA. By December 1969,
there were four nodes on the infant network, which was named ARPANET, after its
Pentagon sponsor” (Sterling, February 1993). Those four nodes consisted of one at
UCLA, one at UCSB, one at Stanford Research, now called SR International, and one in
Utah (See Figure 1). It was in 1969 that ARPANET delivered its first message. It was
a node to node communication from UCLA to Stanford that said “LOGIN” or “log win”
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according to another source. Of course, the communication failed and Stanford
received “LO”. The Internet never bombs for us today, right? The Internet has been
growing ever since. Today the term Internet is generally accepted to mean
“international network of networks” and it has become so ingrained in society that it is
hard to imagine life without it. It has allowed a flow of information that has increased
human interaction through social networking, enabled incredible commercial successes,
and even aided in revolutions that may one day result in freedom for many. It is so
powerful that some governments do everything they can to limit their citizens’ access,
while others look for ways to tax it.
Internet Standards and Protocols
It was during the ARPANET development that many of the standards and
protocols that we use today came about. Let’s consider the challenges faced in the
goal to connect devices across long distances. It really seems like a miracle that global
communication can possibly work when one considers the vast number of
manufacturers, providers and people that are involved. Think for a moment about a
person in his or her den using any brand of computer connected to a service through
many other pieces of equipment made by any number of different companies, possibly
passing through several different countries, where people speak different languages.
How in the world can this work? It is the existence of standards that make
communication like that of the Internet possible. So, where do these standards come
from? For one, they can occur because some company has a monopoly for a long time.
For example, until 1982 AT&T had a monopoly in the form of the Bell System. Up to
that time, we did not even buy our own telephones. We leased the phones made by an
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AT&T subsidiary, Western Electric. When the breakup took place, it was only a matter
of weeks before people were able to buy their own phone at the local general store.
How was that possible? It was possible because over the years AT&T had developed
standard configurations for all sorts of equipment, down to the small connector that
plugged into the wall. All the new manufacturers had to do was build equipment that
used that those same specifications.
Another way that a standard evolves is by a product being so popular that its
technology becomes a standard. Take the example of Centronics, a major printer
manufacturer when the first microcomputers made the scene in the late 1970s.
Centronics was such a prominent printer company at the time, that the connector (See
Figure 2) that they used to interface their equipment with computers became the
Institute of Electrical and Electronic
Engineers (IEEE) 1284 standard. Another
good example of this case is the IBM PC.
The technology of that computer in 1980
FIGURE 2
became the standard for microcomputers for
years and it can be said that the IBM PC is the standard for most desktop computers on
the market today. Finally, another way that standards are developed is through
standard setting organizations, such as the IEEE that was referenced above. IEEE, is a
professional association responsible for many standards in use today. The International
Organizations for Standardization, ISO, is a standard setting organization with
representatives from many other organizations. The Telecommunications Industry
Association, TIA, and the Electronic Industries Alliance, EIA, for example, define a
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standard identified as TIA/EIA-568 for high-performance, twisted pair network cabling.
It is not the purpose of this paper to itemize all of the standards used on the Internet,
even if such a paper were possible. It is merely to point out that the reason that
communication across the Internet works is because such standards exist. Every
connection one encounters from his or her own device to another at some other place in
the world works because the network was built in compliance with international
standards.
When discussing communication between networks of devices, one usually
organizes the process into layers with each layer responsible for a specific phase of the
task. For example, one layer might define the physical components of the system to
include the type of medium being used (copper, glass, or air), the specification of
various connectors, the format of the data, 1s and 0s, that are being transmitted and so
on. Another layer might be responsible for the act of communicating between just two
devices. Such a layer might be responsible for managing the flow of data between the
two devices. There would be a layer responsible for finding a way to identify devices
globally and figuring out how to get the message from point A to point X, Y, or Z, while
another might be responsible for making sure what was sent from A is what arrived at Z.
There have been a number of different models of these layers. One such model that
has been taught in many network classes over the years is the Open Systems
Interconnection Model, OSI. This model has seven layers, some of which are well
documented and some not so much. However, after over 40 years of development and
refinement, the model that has become the dominant one is the very model initiated by
ARPANET. It is the Transmission Control Protocol/Internet Protocol or TCP/IP model.
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First, perhaps we should define the term protocol. It means the rules used in
communication. It makes no difference whether the task is diplomatic communication or
network communication, it is necessary that there be defined rules through which
entities, diplomats or computers, communicate. The purpose is to ensure that there is
accurate information passed between those entities. In the case of our network
communication protocols, there are many. The two that make up the basis for TCP/IP
are Transmission Control Protocol and Internet Protocol. Let us touch just briefly on
these two protocols. Transmission Control Protocol, TCP, is the set of rules that enable
end to end communication. That is to say, it is not responsible for all of the intermediate
hops that make up the route from source to destination, but only for ensuring that the
data sent is the data eventually received on the other side. TCP will arrange the
appointment, let us say, between sender and receiver for the message of data. In a
packet switching environment, a message is broken in many smaller pieces called
packets and these packets may travel along different routes to get to the destination. It
is the Transmission Control Protocol that has to ensure that all those packets are put
back together again in the correct order once they reach the destination. The Internet
Protocol is the set of rules that, among other things, actually determines issues like the
addresses of the hosts along the global network. The IP Address is the address that is
used in a TCP/IP environment and every device that is connected must have its own,
unique address. That statement carries with it conditions that need to be explained in
another paper. It really is not true, but does express the principle of addressing on the
Internet. In fact, the only entity that has any semblance of global authority on the
Internet is the Internet Corporation for Assigned Names and Numbers (ICANN). ICANN
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is responsible for allotting those Internet addresses through the Internet Assigned
Numbers Authority (IANA), which it operates. ICANN also issues those domain names
like www.umobile.edu, which we will talk about shortly (Welcome to ICANN, 2013). IP
also determines the route each packet will take to navigate to the destination. Yes, it is
possible, even likely, that the packets that make up one single message will travel
different routes to get to the other end. IP is not concerned that all the packets make it
to the other end. It is purely limited to ensuring that the packet makes it to the next hop.
It is TCP that has the responsibility for making sure that all the packets get there and
are put back together in the proper way.
ARPANET was eventually replaced by NSFnet, which finally ended up as what
we know today as the Internet. There is another story for another paper.
Applications
The first applications that were created for the ARPANET network were
electronic mail (Email), File Transfer Protocol (FTP), and telnet. Note that these
applications were in existence long before the World Wide Web. Email allows one to
send messages across the Internet. File Transfer Protocol, FTP, allows one to transfer
files from one host to another and telnet is a utility that allows one to log in to a host as
a remote terminal. These old applications are still very popular and in use today,
sometimes in concert with the Web.
Now we will examine the World Wide Web often abbreviated the Web. “In
1989, Tim Berners-Lee invented the World Wide Web. He coined the term "World Wide
Web", wrote the first World Wide Web server, “httpd”, and the first client program (a
browser and editor), "WorldWideWeb," in October 1990. He wrote the first version of the
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"HyperText Markup Language (HTML), the document formatting language with the
capability for hypertext links that became the primary publishing format for the Web. His
initial specifications for URL, HTTP, and HTML were refined and discussed in larger
circles as Web technology spread.” (Facts About W3C, 2013) The World Wide Web is
not the same as the Internet. It is a collection of protocols and applications that may be
used to effectively navigate the Internet and access information globally. It is to a great
extent based on its own protocol called the Hypertext Transfer Protocol, HTTP, which
enables the transfer of documents, graphics, audio and video files (World Wide Web,
2013). There are a number of different scripting and programming languages for the
web, such as Hypertext Markup Language (HTML), Java, Visual Basic, PHP, and
others. One of the key components of the web is hypertext, text that references other
text, images, and more, which the reader can immediately access (Hypertext, 2013).
These references are referred to as hyperlinks. Simply by clicking on a hyperlink,
information from another source is immediately downloaded to the user’s client
machine.
The Web is a client/server system in which the user’s application, the Web client,
requests a document from a remote host, the Web server. WorldWideWeb was LernerLee’s web client. Another Web client that really popularized the Web was Mosaic,
developed at the National Center for Supercomputing Applications at the University of
Illinois Urbana-Champaign, beginning in 1992. It reportedly got its name because it
supported multiple Internet protocols. Mosaic was soon followed by Netscape
Navigator (Mosaic (web browser), 2013). Today, the most popular Web clients are
Microsoft’s Internet Explorer, Google’s Chrome, Mozilla Firefox, which descended from
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Netscape Navigator, and Apple’s Safari. On the other side of the link, the server side,
the two most often found are Apache, which is a Unix/Linux based Web server and
Internet Information Services, IIS, which is the Windows product. There are others. In
addition to HTML and HTTP, another title to recognize is Uniform Resource Locator
(URL). Simply put, this is the address that one enters into the Web client to access a
page located on some other Web server.
Previously, we discussed the fact that IP provides the unique address used by
hosts on the Internet. For example, entering 176.32.98.166 into the URL of the web
browser will take one to Amazon’s website. 50.112.92.119 will take a user to Netflix.
Imagine trying to actually remember the IP addresses of one’s 10 favorite websites. For
most people that would not be possible. So, the Domain Name System was created to
allow user-friendly names that may be used to navigate the Web rather than the IP
addresses. So, one may enter www.amazon.com rather than the number referenced
above to reach that great website. Certainly, it is much easier for us to remember such
a domain name.
Finally, is any one in charge of the Internet? The answer is that many people are
in charge. At least, they are in charge of their own piece of this vast network. The
system administrator of each autonomous network that is connected to the Internet has
as much control over what they will allow on the Web as they need, when users access
it from the network that they manage. So, an administrator has the ability to filter
Internet traffic based on the organization’s policies. Now, if the question is does anyone
have control of the global Internet, the answer is no. Then, one might ask how
governments restrict access, if no one is in charge. They do so by means of laws that
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govern those businesses that provide Internet services, for example. If an Internet
Service Provider, ISP, wants to keep its license to do business, then, obviously, it must
comply with any law established by the government, which could include filtering traffic.
Conclusion
The difficulty in communication along the vast network of devices on the Internet
would seem insurmountable, when one considers the sheer number of different entities
involved. The variety of hardware necessary is daunting: As is the variety of people,
services, even countries involved. Yet, as we have seen, it is all possible because of
the existence of well-defined standards and protocols that have been developed for the
task. In addition to that, there have been some excellent applications, such as email,
and the Web, created to enable us to access people and services all over the world.
The result has been a fantastic increase in the power of men and women to compete in
business and politics, and truly change the world. Remember, though, what happened
when men demonstrated this kind of power back in Babylon many years ago.
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References
Facts About W3C. (2013, November 21). Retrieved from W3C: http://www.w3.org/Consortium/facts
Hypertext. (2013, November 21). Retrieved from Ask: http://www.ask.com/wiki/Hypertext?qsrc=3044
Inductees. (2013, November 23). Retrieved from Internet Hall of Fame:
http://internethalloffame.org/inductees/robert-taylor
Inventor of the Week. (2000, July). Retrieved from LEMELS N-MIT:
http://web.mit.edu/invent/iow/cerf.html
Leiner, B. M., Cerf, V. G., Clark, D. D., Kahn, R. E., Kleinrock, L., Lynch, D. C., . . . Wolff, S. (2013,
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http://www.internetsociety.org/internet/what-internet/history-internet/brief-history-internet
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n&ap=ask.com
Moses, P. (n.d.). The Bible. New International Version.
Sterling, B. (February 1993). Internet [aka "S Short Historyof the Internet"]. The Magazine of Fantasy
and Science Fiction.
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http://www.webopedia.com/TERM/W/World_Wide_Web.html