The revolutionary idea
In 1962, as Communism grew stronger, the US Air Force asked a small team of researchers to create a military communications network that could withstand a nuclear strike. The concept of this network relied on a decentralised system, so that the network could continue to function even if one or several machines were destroyed.
The Baran model
Paul Baran is considered one of the main figures in the creation of the Internet. In 1964, he had the idea to create a network in the form of a large web. He had realized that a centralised system was vulnerable, as destroying its core would bring down all communications. For this reason, he created a hybrid network using both mesh and star topology, in which data would travel dynamically, "searching" for the clearest pathway, and "waiting" if all routes were blocked. This technology was called "packet switching."
In August 1969, separate from the military project, the experimental network ARPANET was created by ARPA (Advanced Research Projects Agency, a division of the United States Department of Defense) in order to link four universities together:
- The Stanford Research Institute;
- The University of California at Los Angeles;
- The University of California at Santa Barbara;
- The University of Utah.
The ARPANET is now considered the precursor to the Internet. At that time, it already included several fundamental characteristics of the current network:
- One or several cores could be destroyed without disrupting the network's operation;
- Communication between machines could take place without the direction of a central machine;
- The protocols used were basic.
In 1971, Ray Tomlinson developed a new means of communication: electronic mail. The contents of the first e-mail were:
Additionally, the character "@" was already being used to separate the user's name from the rest of the address.
In July 1972, Lawrence G. Roberts improved upon the horizons pioneered by Tomlinson by developing the first application for listing, selectively reading, archiving, and responding to or forwarding an e-mail. Since then, e-mail has never stopped growing in influence, becoming the most common use of the Internet at the turn of the 21st century.
Also in 1972 (October), the ARPANET was introduced to the general public for the first time, at the ICCC (International Computer Communication Conference). Around that same time, ARPA became DARPA (Defense Advanced Research Projects Agency) and the term "internetting" was used to refer to ARPANET, which was later shortened to "Internet."
The NCP protocol then in use did not enable error checking, and therefore was in principle usable only on the ARPANET, whose infrastructure was correctly controlled.
For this reason, Bob Kahn, who came to ARPA in 1972, started work on a the foundation for a new protocol, called TCP, for routing data over a network by fragmenting it into small packets. In the spring of 1973, he asked Vinton Cerf (then at Stanford) to help him build the protocol.
In 1976, the DoD decided to use TCP on the ARPANET, composed of 111 interconnected machines. In 1978, TCP was split into two protocols: TCP and IP, forming what would become the TCP/IP suite.
The naming system DNS used today was implemented in 1984, in order to remedy the lack of flexibility inherent in hosts files, in which machine names and their respective addresses were stored in text files that had to be updated manually.
In 1969, Steve Crocker (then at the University of California) perfected the "Request for Comments" (RFC) system. It was a group of documents in memorandum form, allowing researchers to share their work.
Jon Postel (6 August 1943 - 16 October 1998) was in charge of administrating these documents until his death.
The World Wide Web
Beginning in 1980, Tim Berners-Lee, a researcher at CERN in Geneva, engineered a hypertext navigation system, and developed, with the help of Robert Cailliau, a software program called Enquire for navigating it.
In late 1990, Tim Berners-Lee finished the protocol HTTP (Hypertext Transfer Protocol), as well as HTML (HyperText Markup Language) for browsing networks by using hyperlinks. The World Wide Web was born.