Monday, 30 September 2019

                                                   HISTORY OF INTERNET

·         The Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP).

·         It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked web pages and other resources of the World Wide Web (WWW).

·         It is a global network connecting millions of computers. More than 1000 countries are linked into exchanges of data, news and opinions. Unlike online services, which are centrally controlled, the Internet is decentralized by design. Each Internet computer, called a host, is independent. Its operators can choose which Internet services to use and local services to make available to the global Internet community.
  • It is also a world wide connection of computer to share information 

  • Historical Background of the Internet                                                                                              
·         The USSR's launch of Sputnik spurred the United States to create the Advanced Research Projects Agency, known as ARPA, in February 1958 to regain a technological lead.

·         The sputnik was a series of robotic spacecraft missions launched by the Soviet Union.

·         The first of these, Sputnik 1, launched the first man-made object to orbit the Earth. That launch took place on October 4, 1957 as part of the International Geophysical Year and demonstrated the viability of using artificial satellites to explore the upper atmosphere.

·         The surprise launch of Sputnik 1, coupled with the spectacular failure of the United States' first two Project Vanguard launch attempts, shocked the United States, which responded with a number of early satellite launches, including Explorer 1, Project SCORE, and Courier 1B. The Sputnik crisis also led to the creation of the Advanced Research Projects Agency (renamed the Defense Advanced Research Projects Agency in 1972): DARPA, and NASA, and an increase in U.S. government spending on scientific research and education.

·         In 1969, ARPA, a part of the Department of Defense (DOD), awarded a contract to the firm of Bolt Beranek and Newman (BBN) to construct a computer network. The network was used to link researchers at universities with defense contractors, researchers, scientists and military contractors so that they can share information and resources. This network was called the ARPANET.

·         Between 1969 and 1983, minicomputers, mainframes and super computers made up the networks. This network had file transfer capabilities, electronic mail and mailing list services.

·         In 1973, Advanced Research Project Agency (ARPA) was changed to the Defense Advanced Research Agency (DARPA) and the resulting network to DARPANET.

·         An important task for this newly named agency was to begin a project called “the interneting project”, which would start the process of linking different networks together.
·         The principal goals of the interneting project were to:
Move from circuit switching (ARPA) to Packet switching network (DARPA)
Link these packet switching networks together
Overcome network specific protocols
Study ways to pass traffic from one network to another
Establish Internet protocols and standards
·         Previous networking efforts used circuit switching which required two computers to be continuously connected in order to form a network. It was like having a rail track on which a single train could travel.

·         The packet switching system allows the creation of a data highway that could handle large amount of data including voice, text, video, etc. Each data packet was given the computer equivalent of a map and time stamp so that it would be sent to the right destination and the reviewer would know when the message started. At its destination the message would be reassembled from the packet parts so either machine or human could read it.

                                                   HISTORY OF INTERNET ·          The Internet is a worldwide, publicly accessible seri...