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The Internet. The History. On October 4, 1957 the Soviet Union (now Russia) launched the first satellite, called “Sputnik 1” into Earth’s orbit. The History.
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The History • On October 4, 1957 the Soviet Union (now Russia) launched the first satellite, called “Sputnik 1” into Earth’s orbit.
The History • In 1958, President Eisenhower and the U.S. government created an organization titled the Advanced Research Projects Agency (ARPA) that could research and develop ideas and technology for the future. • ARPA is still in existence but is now called DARPA, the Defense Advanced Research Projects Agency.
The Internet • The Internet is a world-wide network of computers. • A network is two or more computers that are connected in order to share resources and exchange information with one another.
Types of Networks • There are two main types of networks: • local area networks (LANs) • wide area networks (WANs).
Types of Networks • A local area network (LAN) is a group of computers connected within a confined geographic area. They can extend over several yards or even miles, but are generally restricted to one building.
Types of Networks • A wide area network (WAN) consists of two or more LANs that span a wide geographic area or even a continent.
Network Communication Networks communicate using a client and server. The server is a fast, reliable computer that is responsible for storing information on a network. • The client is a computer that is responsible for requesting information on a network.
The History • In 1960, Joseph Licklider, an employee at DARPA, suggested the idea of a computer network. "A network of such [computers], connected to one another by wide-band communication lines [which provided] the functions of present-day libraries together with anticipated advances in information storage and retrieval and [other] symbiotic functions."
The History • In 1962, Licklider wrote a detailed description of a computer network. • After working for 5 years on the network, Licklider left DARPA.
The History • In 1969, his successors, Larry Roberts and Bob Taylor completed the computer network. • It was called the Advanced Research Projects Agency Network or ARPANET for short.
The History • The first ARPANET network was established between the University of California, Los Angeles and the Stanford Research Institute on October 29, 1969 at 10:30pm. • At that time, ARPANET was only accessible to people who understood the technologies that powered it.
The Web • The World Wide Web or WWW refers to the actual information that can be accessed through the network connections that make up the Internet.
The Web • HTTP or the Hypertext Transfer Protocol is the set of rules used to transfer information over a the World Wide Web. • HTTP separates information into sub parts called packets prior to transferring data and reassembles the packets upon receipt of the data. • Routers are devices on a network that are connected between a client and a server that direct packets to the appropriate location.
The Web • Every machine on a network has a unique Internet Protocol (IP) address that identifies it. 69.201.49.232 32.107.63.241 71.69.237.46
The Web • IP address are hard to remember so we use host or domain names. • A host name is a mnemonic (memorable)name that identifies an Internet resource such as a website. • Host names are created as a combination of letters, numbers or hyphens and a top level domain (TLD) such as .com, .net, .org, etc.
The Web • A Uniform Resource Locator (URL) is a complete path to an Internet Resource. • URLs include the HTTP protocol, the host name, the TLD and the path to the resource.
The History • In 1984, researchers and technicians at the University of Wisconsin developed the Domain Name System (DNS) – the system for naming hosts.
The History • In 1990, a man named Tim Berners-Lee created the first web browser, a web language called HTML, the WWW software and HTTP. • At that point, the connections on ARPANET and the technologies powering it became known as the Internet.
The Web • Everything that exists on the Web is created with the help of a Web Language. • We will learn more about Web Languages later.