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Running Head: THE INTERNET 1 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 THE INTERNET 2 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 THE INTERNET 3 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). THE INTERNET 4 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” THE INTERNET 5 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 THE INTERNET 6 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 THE INTERNET 7 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. THE INTERNET 8 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 THE INTERNET 9 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 THE INTERNET 10 "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 THE INTERNET 11 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 THE INTERNET 12 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. THE INTERNET 13 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, November 18). The Internet. Retrieved from Internet Society: http://www.internetsociety.org/internet/what-internet/history-internet/brief-history-internet Mosaic (web browser). (2013, November 21). Retrieved from Ask: http://www.ask.com/wiki/Mosaic_(web_browser)?o=2800&qsrc=999&ad=doubleDown&an=ap 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. The Birth of the Internet. (2013, November 18). Retrieved from Webopedia: http://www.webopedia.com/DidYouKnow/Internet/2002/BirthoftheInternet.asp The Invention of the Internet. (2013, November 18). Retrieved from History.com: http://www.history.com/topics/invention-of-the-internet Waldrop, M. (2008, April). About/History/First 50 Years. Retrieved from DARPA: www.darpa.mil Welcome to ICANN. (2013, November 20). Retrieved from Internet Corporation for Assigned Names and Numbers: http://www.icann.org/en/about/welcome World Wide Web. (2013, November 21). Retrieved from Webopedia: http://www.webopedia.com/TERM/W/World_Wide_Web.html