ARPANET: Difference between revisions

During the Cold War era, one of the primary concerns for the United States government was to find ways of protecting its military communications system, as wel as ways to make its command and control network able to survive a nuclear attack from the Soviet Union. As a result of the Soviet Union launching Sputnik in 1957,<ref>[http://www.dei.isep.ipp.pt/~acc/docs/arpa--1.html Part I: The history of ARPA leading up to the ARPANET]</ref> in 1958 US President Dwight Eisenhower instructed the creation of the Advance Research Project Agency (ARPA), which later became known as [[DARPA]].<ref>[http://www.livinginternet.com/i/ii_darpa.htm DARPA/ARPA]</ref>

The basis of the academic research for ARPANET started with [[Paul Baran]], a researcher from [[Research and Development|RAND]], Inc., who would one day be considered one of the fathers of the Internet. In 1962, Baran suggested that a more robust communications network using redundancy and digital technology be designed. Although his idea was dismissed by many, Baran continued to work on developing the idea with colleagues at RAND. He envisioned a method of distributed communications wherein a network of unmanned nodes would serve as switches to route information from one node to another until the information reached its final destination. He later developed [[packet switching]], a method of dividing information into "message blocks"  before sending them out to a network. Each message block was to be sent separately and then rejoined as a whole when reaching the final destination.<ref>[http://www.rand.org/about/history/baran.html Paul Baran and the Origins of the Internet]</ref>

During the same year, DARPA commissioned Dr. [[J.C.R. Licklider]] from Bolt, Beranek and Newman to lead the [[IPTO| Information Processing Techniques Office]], which was mandated to further develop the Semi-Automatic Ground Environment (SAGE) program and build the first wide area computer network for the cross country radar defense system, interconnecting the three major defense sites of the United States in a manner that was capable of surviving a nuclear attack.

Licklider envisioned the project based on Baran's method of packet switching.<ref>[http://cs.gmu.edu/cne/pjd/TT/innov_story.pdf The World Wide Web, a Paradigm of Innovation]</ref> He also visualized a universal network that would allow people to communicate with each other using the computer. He referred to the first group of computer specialists working on the research project as the "Intergalactic Network." Licklider's interest in connecting the community through a computer network resulted in the creation of the ARPANET.<ref>[http://www.dei.isep.ipp.pt/~acc/docs/arpa--1.html Licklider]</ref> He believed in the "promise offered by the computer as a communication medium between people, not as an arithmetic engine."<ref>[http://www.columbia.edu/~hauben/CS/n www.columbia.edu]</ref> In 1964, Licklider resigned from IPTO as Director and went to work for [[IBM]].

Licklider was succeeded by [[Ivan Sutherland]], who developed the Sketchpad program which enabled computer displays to be saved and modified in memory. He also developed computer graphics. Inspired by his predecessors' vision of a universal network, in 1965 Sutherland awarded a contract to [[Lawrence Roberts]] from MIT to develop the computer networking technology. Roberts worked with [[Thomas Marril]] and together they were able to implement the first packet dial-up telephone connection exchange between a TX-2 computer at MIT and a Q-32 computer in California.<ref>[http://www.livinginternet.com/i/ii_ipto.htm Sutherland]</ref>

In 1966, Robert Taylor succeeded Sutherland as IPTO Director.. He lobbied for additional funding to be able to carry out a research project to achieve a distributed communication network. A one million dollar funding was promised to him by DARPA then-Chief [[Charlie Hertzfeld]], and Roberts was hired by IPTO as Chief Scientist. On June 21, 1968, Taylor approved the Resource Sharing Computer Network Report, a plan to create ARPANET, which was prepared by Roberts.<ref>[http://www.livinginternet.com/i/ii_ipto.htm Taylor Appproved Creation of ARPANET]</ref> ARPANET was officially developed on August 30, 1969.<ref>[http://www.livinginternet.com/i/ii_arpanet.htm ARPANET officially created]</ref> Lawrence Roberts became Director of IPTO the following month.

In 1968, computer experts from four of the research laboratories receiving funding from IPTO were called together to identify and solve the technical problems associated with the development and completion of the ARPANET. [[Elmer Shapiro]] from the Stanford Research Institute (SRI) organized the first meeting, as instructed by ARPA, to discuss host-to-host problems. The meeting was attended by [[Steve Crocker]], who represented UCLA, [[Steve Carr]], from University of Utah, [[Jeff Rulifson]] from SRI, and [[Ron Stoughton]] from UCSB. The group decided to meet regularly, and became known as the [[NWG|Network Working Group]]. Crocker describe what transpired during the first meeting with the following statement:

<blockquote>"''With no specific service definition in place for what the IMPs [Interface Message Processor] were providing to the hosts, there wasn't any clear idea of what work the hosts had to do. Only later did we articulate the notion of building a layered set of protocols with general transport services on the bottom and multiple application- specific protocols on the top. More precisely, we understood quite early that we wanted quite a bit of generality, but we didn't have a clear idea how to achieve it. We struggled between a grand design and getting something working quickly.''"<ref>[http://www.dei.isep.ipp.pt/~acc/docs/arpa--2.html History of ARPANET Part II:The Network Working Group]</ref></blockquote>

The NWG's initial advance protocol developments were [[DEL]] (Decode-Encode-Language) and [[NIL]] (Network Interchange Language), which were intended to give instruction on how to understand messages received from a sender. In 1969, Bolt, Beranek and Newman (BBN) submitted a detailed report on the host-IMP interface specifications from the IMP side, which provided the NWG a basic starting point to develop the ARPANET, analyze its cost, performance and reliability.<ref>[http://www.dei.isep.ipp.pt/~acc/docs/arpa--2.html History of ARPANET Part II: The Network Working Group]</ref>

A Request for Comments ([[RFC]]) was started by the NWG when they realized that the discussions during their meetings needs to be recorded. Crocker organized the notes and noted the discussions in their meetings with the label Request for Comments. According to Crocker, the NWG had a vision for inter computer communication but they struggled to create a detailed protocol design. The RFCs served as a document to give status updates to the members of the NWG. The RFCs were open and provided an exchange of ideas and information between the computer scientists working on the ARPANET.<ref>[http://www.dei.isep.ipp.pt/~acc/docs/arpa--3.html Part III: About RFC's as "Open" Documentation]</ref>