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Thread: ARPANET

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    ARPANET

    The first permanent ARPANET link is established between UCLA and SRI.
    November 21, 1969



    ARPANET logical map, March 1977

    The Advanced Research Projects Agency Network (ARPANET) was one of the world's first operational packet switching networks, the first network to implement TCP/IP, and the progenitor of what was to become the global Internet. The network was initially funded by the Advanced Research Projects Agency (ARPA, later DARPA) within the U.S. Department of Defense for use by its projects at universities and research laboratories in the US. The packet switching of the ARPANET, together with TCP/IP, would form the backbone of how the Internet works. The packet switching was based on concepts and designs by American engineer Paul Baran, British scientist Donald Davies and Lawrence Roberts of the Lincoln Laboratory. The TCP/IP communication protocols were developed for ARPANET by computer scientists Robert Kahn and Vinton Cerf.

    Packet switching, today the dominant basis for data communications worldwide, was a new concept at the time of the conception of the ARPANET. Prior to the advent of packet switching, both voice and data communications had been based on the idea of circuit switching, as in the traditional telephone circuit, wherein each telephone call is allocated a dedicated, end to end, electronic connection between the two communicating stations. Such stations might be telephones or computers. The (temporarily) dedicated line is typically composed of many intermediary lines which are assembled into a chain that stretches all the way from the originating station to the destination station. With packet switching, a data system could use a single communications link to communicate with more than one machine by collecting data into datagrams and transmitting these as packets onto the attached network link, as soon as the link becomes idle. Thus, not only can the link be shared, much as a single post box can be used to post letters to different destinations, but each packet can be routed independently of other packets.

    The earliest ideas for a computer network intended to allow general communications among computer users were formulated by computer scientist J. C. R. Licklider of Bolt, Beranek and Newman (BBN), in April 1963, in memoranda discussing his concept for an "Intergalactic Computer Network". Those ideas contained almost everything that composes the contemporary Internet. In October 1963, Licklider was appointed head of the Behavioral Sciences and Command and Control programs at the Defense Department's Advanced Research Projects Agency — ARPA (the initial ARPANET acronym). He then convinced Ivan Sutherland and Bob Taylor that this computer network concept was very important and merited development, although Licklider left ARPA before any contracts were let that worked on this concept.

    Ivan Sutherland and Bob Taylor continued their interest in creating such a computer communications network, in part, to allow ARPA-sponsored researchers at various corporate and academic locales to put to use the computers ARPA was providing them, and, in part, to make new software and other computer science results quickly and widely available. In his office, Taylor had three computer terminals, each connected to separate computers, which ARPA was funding: the first, for the System Development Corporation (SDC) Q-32, in Santa Monica; the second, for Project Genie, at the University of California, Berkeley; and the third, for Multics, at MIT. Taylor recalls the circumstance: "For each of these three terminals, I had three different sets of user commands. So, if I was talking online with someone at S.D.C., and I wanted to talk to someone I knew at Berkeley, or M.I.T., about this, I had to get up from the S.D.C. terminal, go over and log into the other terminal and get in touch with them. I said, "Oh Man!", it's obvious what to do: If you have these three terminals, there ought to be one terminal that goes anywhere you want to go. That idea is the ARPANET". Somewhat contemporaneously, several other people had (mostly independently) worked out the aspects of "packet switching", with the first public demonstration presented by the National Physical Laboratory (NPL), on 5 August 1968, in the United Kingdom.


    Len Kleinrock and the first Interface Message Processor.

    By mid-1968, Taylor had prepared a complete plan for a computer network, and, after ARPA's approval, a Request for Quotation (RFQ) was sent to 140 potential bidders. Most computer science companies regarded the ARPA–Taylor proposal as outlandish, and only twelve submitted bids to build the network; of the twelve, ARPA regarded only four as top-rank contractors. At year's end, ARPA considered only two contractors, and awarded the contract to build the network to BBN Technologies on 7 April 1969. The initial, seven-man BBN team were much aided by the technical specificity of their response to the ARPA RFQ – and thus quickly produced the first working computers. This team was led by Frank Heart. The BBN-proposed network closely followed Taylor's ARPA plan: a network composed of small computers called Interface Message Processors (IMPs: today called routers), that functioned as gateways interconnecting local resources. At each site, the IMPs performed store-and-forward packet switching functions, and were interconnected with modems that were connected to leased lines, initially running at 50kbit/second. The host computers were connected to the IMPs via custom serial communication interfaces. The system, including the hardware and the packet switching software, was designed and installed in nine months.

    The first-generation IMPs were initially built by BBN Technologies using a rugged computer version of the Honeywell DDP-516 computer configured with 24kB of expandable core memory, and a 16-channel Direct Multiplex Control (DMC) direct memory access unit. The DMC established custom interfaces with each of the host computers and modems. In addition to the front-panel lamps, the DDP-516 computer also features a special set of 24 indicator-lamps showing the status of the IMP communication channels. Each IMP could support up to four local hosts, and could communicate with up to six remote IMPs via leased lines. The network connected one computer in Utah with three in California. Later, the Department Of Defense allowed the universities to join the network for sharing hardware and software resources.

    Common ARPANET lore posits that the computer network was designed to survive a nuclear attack. In A Brief History of the Internet, the Internet Society describes the coalescing of the technical ideas that produced the ARPANET:

    It was from the RAND study that the false rumor started, claiming that the ARPANET was somehow related to building a network resistant to nuclear war. This was never true of the ARPANET, only the unrelated RAND study on secure voice considered nuclear war. However, the later work on Internetting did emphasize robustness and survivability, including the capability to withstand losses of large portions of the underlying networks.

    Although the ARPANET was designed to survive subordinate-network losses, the principal reason was that the switching nodes and network links were unreliable, even without any nuclear attacks. About the resource scarcity that spurred the creation of the ARPANET, Charles Herzfeld, ARPA Director (1965–1967), said:

    The ARPANET was not started to create a Command and Control System that would survive a nuclear attack, as many now claim. To build such a system was, clearly, a major military need, but it was not ARPA's mission to do this; in fact, we would have been severely criticized had we tried. Rather, the ARPANET came out of our frustration that there were only a limited number of large, powerful research computers in the country, and that many research investigators, who should have access to them, were geographically separated from them.

    Packet switching pioneer Paul Baran affirms this, explaining: "Bob Taylor had a couple of computer terminals speaking to different machines, and his idea was to have some way of having a terminal speak to any of them and have a network. That's really the origin of the ARPANET. The method used to connect things together was an open issue for a time."


    Historical document: First ARPANET IMP log: the first message ever sent via the ARPANET, 10:30 pm, 29 October 1969. This IMP Log excerpt, kept at UCLA, describes setting up a message transmission from the UCLA SDS Sigma 7 Host computer to the SRI SDS 940 Host computer

    The initial ARPANET consisted of four IMPs:

    University of California, Los Angeles (UCLA), where Leonard Kleinrock had established a Network Measurement Center, with an SDS Sigma 7 being the first computer attached to it;
    The Stanford Research Institute's Augmentation Research Center, where Douglas Engelbart had created the ground-breaking NLS system, a very important early hypertext system (with the SDS 940 that ran NLS, named "Genie", being the first host attached);
    University of California, Santa Barbara (UCSB), with the Culler-Fried Interactive Mathematics Center's IBM 360/75, running OS/MVT being the machine attached;
    The University of Utah's Computer Science Department, where Ivan Sutherland had moved, running a DEC PDP-10 operating on TENEX.

    The first message on the ARPANET was sent by UCLA student programmer Charley Kline, at 10:30 pm on 29 October 1969, from Boelter Hall 3420. Kline transmitted from the university's SDS Sigma 7 Host computer to the Stanford Research Institute's SDS 940 Host computer. The message text was the word login; the l and the o letters were transmitted, but the system then crashed. Hence, the literal first message over the ARPANET was lo. About an hour later, having recovered from the crash, the SDS Sigma 7 computer effected a full login. The first permanent ARPANET link was established on 21 November 1969, between the IMP at UCLA and the IMP at the Stanford Research Institute. By 5 December 1969, the entire four-node network was established.

    In March 1970, the ARPANET reached the East Coast of the United States, when an IMP at BBN in Cambridge, Massachusetts was connected to the network. Thereafter, the ARPANET grew: 9 IMPs by June 1970 and 13 IMPs by December 1970, then 18 by September 1971 (when the network included 23 university and government hosts); 29 IMPs by August 1972, and 40 by September 1973. By June 1974, there were 46 IMPs, and in July 1975, the network numbered 57 IMPs. By 1981, the number was 213 host computers, with another host connecting approximately every twenty days.

    In 1973 a transatlantic satellite link connected the Norwegian Seismic Array (NORSAR) to the ARPANET, making Norway the first country outside the US to be connected to the network. At about the same time a terrestrial circuit added a London IMP.

    In 1975, the ARPANET was declared "operational". The Defense Communications Agency took control since ARPA was intended to fund advanced research.

    In 1983, the ARPANET was split with U.S. military sites on their own Military Network (MILNET) for unclassified defense department communications. The combination was called the Defense Data Network (DDN). Separating the civil and military networks reduced the 113-node ARPANET by 68 nodes. Gateways relayed electronic mail between the two networks. MILNET later became the NIPRNet.

    The original IMPs and TIPs were phased out as the ARPANET was shut down after the introduction of the NSFNet, but some IMPs remained in service as late as 1989.

    The ARPANET Completion Report, jointly published by BBN and ARPA, concludes that:

    ... it is somewhat fitting to end on the note that the ARPANET program has had a strong and direct feedback into the support and strength of computer science, from which the network, itself, sprang.

    In the wake of ARPANET being formally decommissioned on 28 February 1990, Vinton Cerf wrote the following lamentation, entitled "Requiem of the ARPANET":

    It was the first, and being first, was best,
    but now we lay it down to ever rest.
    Now pause with me a moment, shed some tears.
    For auld lang syne, for love, for years and years
    of faithful service, duty done, I weep.
    Lay down thy packet, now, O friend, and sleep.

    -Vinton Cerf

    Senator Albert Gore, Jr. began to craft the High Performance Computing and Communication Act of 1991 (commonly referred to as "The Gore Bill") after hearing the 1988 report toward a National Research Network submitted to Congress by a group chaired by Leonard Kleinrock, professor of computer science at UCLA. The bill was passed on 9 December 1991 and led to the National Information Infrastructure (NII) which Al Gore called the "information superhighway". ARPANET was the subject of two IEEE Milestones, both dedicated in 2009.



    Computer Networks: The Heralds of Resource Sharing, a 30-minute documentary film featuring Fernando J. Corbato, J.C.R. Licklider, Lawrence G. Roberts, Robert Kahn, Frank Heart, William R. Sutherland, Richard W. Watson, John R. Pasta, Donald W. Davies, and economist, George W. Mitchell.
    "Scenario", a February 1985 episode of the U.S. television sitcom Benson (season 6, episode 20), was the first incidence of a popular TV show directly referencing the Internet or its progenitors. The show includes a scene where the ARPANET is accessed.
    The long running British Science Fiction show, Doctor Who, can also lay claim to the first TV reference to an Internet-like network. In the 1966 serial, The War Machines, a computer located in the newly opened Post Office Tower in London housed WOTAN (an acronym for Will Operated Thought ANalogue), the world's most intelligent computer. On 16 July 1966 (Computer Day), the major computers in the world were to be linked under WOTAN's control. These computers were located at facilities such as the White House, Cape Kennedy, ELDO, TESTAR, RN, Woomera and EFTA.

    In Let the Great World Spin: A Novel, published in 2009 but set in 1974 and written by Colum McCann, a character named The Kid and others use ARPANET from a Palo Alto computer to dial phone booths in New York City to hear descriptions of Philippe Petit's tight rope walk between the World Trade Center Towers.

    In Metal Gear Solid 3: Snake Eater, a character named Sigint takes part in the development of ARPANET after the events depicted in the game.
    The Doctor Who Past Doctor Adventures novel Blue Box, written in 2003 but set in 1981, includes a character predicting that by the year 2000 there will be four hundred machines connected to ARPANET.
    There is an electronic music artist known as Arpanet, Gerald Donald, one of the members of Drexciya. The artist's 2002 album Wireless Internet features commentary on the expansion of the internet via wireless communication, with songs such as NTT DoCoMo, dedicated to the mobile communications giant based in Japan.
    In numerous The X-Files episodes ARPANET is referenced and usually hacked into by The Lone Gunmen. This is most noticeable in the episode "Unusual Suspects".
    Thomas Pynchon's 2009 novel Inherent Vice, set in southern California circa 1970, contains a character who accesses the "ARPAnet" throughout the course of the book.
    The viral marketing campaign for the video game Resistance 2 features a website similar in design and purpose to ARPANET, called SRPANET.
    Episode 11 (season 2) of Person of Interest, "2πr," tells a story of an early hacker (heavily implied to be Finch) who somehow caused ARPANET to transform into the modern internet, using a homemade computer.

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  2. #2
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    Re: ARPANET

    In Illinois, Arpanet was migrated into "Illinet" and was initially limited to goverment, education, and research institutions. They eventually dropped the term as the term "Internet" made more sense because it really wasn't a state based network.
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    Re: ARPANET

    Quote Originally Posted by Slicker View Post
    In Illinois, Arpanet was migrated into "Illinet" and was initially limited to goverment, education, and research institutions. They eventually dropped the term as the term "Internet" made more sense because it really wasn't a state based network.
    I didn't know that, one more for history thread, thanks Slicker.
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