Book Report on: Where Wizards Stay Up Late: The Origins of the Internet

1. Book Report on:Where Wizards Stay Up Late: The Origins of the Internet By: Alexander Scudder For: Dr. Annexstein, CS110

2. Formation of ARPA • The Advanced Research Projects Agency was formed by President Dwight D. Eisenhower in response to the Soviets launching Sputnik into space. ARPA was part of the Pentagon formed to both stop disputes between the branches of the military concerning research grants, and to be a a fast-response team for new technologies, to keep America at the technological edge . However, after the formation of NASA, most of the budget was stripped with the transfer of space and rocket responsibility. After almost being disbanded, the staff of ARPA proposed that the focus of their research shift to more esoteric projects.

3. Timesharing • Allowing multiple users to use the same computer, by dividing system resources among them. but with more users running commands at the same time, the computer will need more resources to coordinate those commands. • Timesharing helped popularize computers, since people who did not usually have access to a computer could use one without taking time from others who may have had more important tasks.

4. ARPAnet and the Interface Message Processors • Bob Taylor, head of the Information Processing Techniques Office at ARPA, first envisioned networking while looking at the 3 separate computers that he used, that were linked to three separate locations in the United States. He proposed to his boss, the director of ARPA, that they should tie computers across the country together, in effort to stop duplication of research effort, and no matter where you were, as long as you were at a computer that was part of the network, you would have access to the data. Another concept that Taylor wanted included was reliability: that if one line went down, the message could take another path to the destination.

5. ARPAnet and the Interface Message Processors (II) • The dual jobs of designing and manufacturing the soft- and hard-ware needed to create this network were put out for companies to bid on. Some of the bids were from giants such as IBM, and even defense contractors. But the bidders that won the task came as a surprise: it went to a small consulting firm in Cambridge, Bolt Beranek and Newman. While they were originally a company that mostly did consulting work for acoustical planning, they eventually moved on to computing, after hiring J.C.R. Licklider, an early and strong advocate of what computers could become. • They decided to have a separate computer do the packet switching work, instead of the host. The term that they used for these specially built computers was Interface Message Processor, which was a modified Honeywell 516 computer. These IMPs would communicate over telephone wires, to the various sites they would eventually be installed at.

6. E-Mail • Though Email had been in use since the early 1960s, on timesharing systems, the first two machine transfer was not done until 1972, by Roy Tomlinson, using his own file-transfer protocol, CPYNET over two computers at BBN. Now the question was how to get this software out on the network. The answer was to include it in the ARPAnet file-transfer protocol. Tomlinson was also the man who came to the decision to use the '@' sign in the addresses, to separate the user's name from the host computer's name. • The only flaw in the system was the fact that you could not access a single message without viewing/printing all of the other messages you had received. Larry Roberts at ARPA solved this problem by writing a program allowing one to file messages, delete them and display a menu of your messages. He called it RD, which was short for "read." The program quickly became popular, and soon most had developed their own version of it, with the features they desired.

7. E-mail (II) • With all of these programs with their own ways of handling mail, it became very inconvenient. A committee was first established in 1973 to attempt to create a standard for email programs, but did not succeed in it. Later, in 1975, formed an electronic discussion group, titled the MsgGroup. After writing a standard, and then rewriting it as less of a standard and more of a basic guideline, many of the programs were rewritten to accept these general rules. It did not take long for disagreements to start up again. But by the time the MsgGroup broke up in the 1980's, they had already formed a community-wide standard for email, that most agreed with.

8. TCP and Ethernet • After the success of ARPAnet over land-based lines, efforts were made to try packet-switching over radio and satellite. Both of these succeeded, but they were not compatible with other networks. The problem was solved by Vint Cerf and Bob Khan, who, together, came up with the idea of a 'gateway', to make other networks appear as if they were running using the same set of protocols. The idea was that this ‘Transmission Control Protocol’ (TCP) would put a message into an ‘envelope’ of data which would be read by the gateways, and forwarded towards the destination, at which the message itself would be read. • Bob Metcalfe, at around the same time as Cerf and Khan were forming TCP, was inventing a new type of network: the local-area network. This network would not connect computers across the world, but instead focus on ones in the next room. The problem he faced was when two computers would transmit data over the same line at the same time, garbling the packets. To circumvent this problem, he made the computer detect that it's data was interfering with another transmission, and stop. It would then resume after a random delay, usually in the thousandths of seconds range. If it kept detecting other traffic on the line, it would wait for longer and longer intervals until it could transmit, keeping it efficient. This system was dubbed the Ethernet.