Terminology and History
– The word ‘internetted’ was used as early as 1849, meaning interconnected or interwoven.
– The word ‘Internet’ was used in 1945 by the United States War Department in a radio operator’s manual and in 1974 as the shorthand form of Internetwork.
– Today, the term ‘Internet’ most commonly refers to the global system of interconnected computer networks, though it may also refer to any group of smaller networks.
– Most publications treated the word ‘Internet’ as a capitalized proper noun when it came into common use, but this has become less common.
– The lowercase form of ‘internet’ is now recommended in every case, although it may still be capitalized to distinguish the global internet from smaller networks.
– In the 1960s, computer scientists began developing systems for time-sharing of computer resources.
– J. C. R. Licklider proposed the idea of a universal network while working at Bolt Beranek & Newman and later leading the Information Processing Techniques Office (IPTO) at ARPA.
– Research into packet switching, one of the fundamental Internet technologies, started in the early 1960s.
– The ARPANET, an experimental resource sharing network, was designed incorporating packet switching from the proposed NPL network.
– The ARPANET development began with two network nodes interconnected between UCLA and SRI International on October 29, 1969.
– The ARPANET gradually developed into a decentralized communications network, connecting remote centers and military bases in the United States.
– Other user networks and research networks, such as the Merit Network and CYCLADES, were developed in the late 1960s and early 1970s.
– International collaborations for the ARPANET were rare initially, but connections were made in 1973 to the Norwegian Seismic Array (NORSAR) and Peter Kirstein’s research group at University College London.
– ARPA projects, international working groups, and commercial initiatives led to the development of protocols and standards for multiple separate networks to become a single network or a network of networks.
– In 1974, Vint Cerf and Bob Kahn published a proposal for A Protocol for Packet Network Intercommunication, using the term ‘internet’ as a shorthand for ‘internetwork.’
Impact
– The Internet reshaped and redefined traditional communication media such as telephone, radio, television, paper mail, and newspapers.
– New services such as email, Internet telephone, Internet television, online music, digital newspapers, and video streaming websites emerged.
– Print publishing adapted to website technology or transformed into blogging, web feeds, and online news aggregators.
– The Internet enabled new forms of personal interaction through instant messaging, Internet forums, and social networking services.
– Online shopping grew exponentially, allowing businesses to extend their presence and affect supply chains across industries.
Governance
– The Internet has no single centralized governance in technological implementation or policies for access and usage.
– Each constituent network sets its own policies.
– The Internet Corporation for Assigned Names and Numbers (ICANN) directs the Internet Protocol address (IP address) space and the Domain Name System (DNS).
– The Internet Engineering Task Force (IETF) is responsible for the technical underpinning and standardization of the core protocols.
– The IETF is a non-profit organization of international participants that anyone may associate with by contributing technical expertise.
Infrastructure
– Internet consists of hardware components and software layers.
– Components include routers, media, repeaters, modems, etc.
– Network nodes are not necessarily Internet equipment.
– Internet packets are guided by IP routers.
– Internet runs across heterogeneous hardware.
– Packet routing involves multiple tiers of ISPs.
– Tier 1 networks exchange traffic directly via high-speed fiber-optic cables.
– Tier 2 and lower-level networks buy Internet transit.
– ISPs may use upstream providers or implement multihoming.
– Large organizations may perform the same function as ISPs.
– Common methods of Internet access include dial-up, broadband, Wi-Fi, satellite, and cellular technology.
– Internet access points exist in public places like libraries and coffee shops.
– Wi-Fi provides wireless access to the Internet.
– Wireless community networks have been established.
– Commercial Wi-Fi services cover large areas in many cities.
Internet Protocol and Subnetwork
– Internet protocol suite is a framework for communication.
– Consists of four conceptual layers: application, transport, networking technologies, and Internet layer.
– Application layer includes protocols like HTTP and data structures like HTML.
– Transport layer provides ordered, reliable delivery (TCP) or unreliable datagram service (UDP).
– Networking technologies interconnect networks and exchange traffic.
– Implements the Internet Protocol (IP) for computers to identify and locate each other.
– IP layer code is independent of the network type it runs over.
– Link layer connects nodes on the same physical link.
– Link layer protocols do not require routers for traversal to other links.
– Encapsulation information is added at each abstraction layer during data transmission.
– IP addresses are used to direct internet packets to their destinations.
– IP addresses consist of fixed-length numbers within the packet.
– IP addresses can be assigned automatically via DHCP or configured manually.
– Domain Name System (DNS) converts domain names to IP addresses for routing purposes.
– IPv4 and IPv6 are the two versions of the Internet Protocol.
– IPv4 defines an IP address as a 32-bit number.
– IPv4 is still in dominant use on the Internet.
– IPv4 was designed to address up to approximately 4.3 billion hosts.
– IPv4 address exhaustion began in 2011.
– The global IPv4 address allocation pool is now exhausted.
– IPv6 provides larger addressing capabilities and more efficient routing.
– IPv6 uses 128 bits for the IP address.
– IPv6 was standardized in 1998.
– IPv6 deployment has been ongoing since the mid-2000s.
– IPv6 is not directly interoperable with IPv4.
– Subnetwork is a logical subdivision of an IP network.
– Computers in a subnet have identical most
The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a network of networks that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the interlinked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing.
The origins of the Internet date back to research to enable time-sharing of computer resources and the development of packet switching in the 1960s. The set of rules (communication protocols) to enable internetworking on the Internet arose from research and development commissioned in the 1970s by the Defense Advanced Research Projects Agency (DARPA) of the United States Department of Defense in collaboration with universities and researchers across the United States and in the United Kingdom and France. The ARPANET initially served as a backbone for the interconnection of regional academic and military networks in the United States to enable resource sharing. The funding of the National Science Foundation Network as a new backbone in the 1980s, as well as private funding for other commercial extensions, encouraged worldwide participation in the development of new networking technologies and the merger of many networks using DARPA's Internet protocol suite. The linking of commercial networks and enterprises by the early 1990s, as well as the advent of the World Wide Web, marked the beginning of the transition to the modern Internet, and generated a sustained exponential growth as generations of institutional, personal, and mobile computers were connected to the network. Although the Internet was widely used by academia in the 1980s, subsequent commercialization is what incorporated its services and technologies into virtually every aspect of modern life.
Most traditional communication media, including telephone, radio, television, paper mail, and newspapers, are reshaped, redefined, or even bypassed by the Internet, giving birth to new services such as email, Internet telephone, Internet television, online music, digital newspapers, and video streaming websites. Newspaper, book, and other print publishing have adapted to website technology or have been reshaped into blogging, web feeds, and online news aggregators. The Internet has enabled and accelerated new forms of personal interaction through instant messaging, Internet forums, and social networking services. Online shopping has grown exponentially for major retailers, small businesses, and entrepreneurs, as it enables firms to extend their "brick and mortar" presence to serve a larger market or even sell goods and services entirely online. Business-to-business and financial services on the Internet affect supply chains across entire industries.
The Internet has no single centralized governance in either technological implementation or policies for access and usage; each constituent network sets its own policies. The overarching definitions of the two principal name spaces on the Internet, the Internet Protocol address (IP address) space and the Domain Name System (DNS), are directed by a maintainer organization, the Internet Corporation for Assigned Names and Numbers (ICANN). The technical underpinning and standardization of the core protocols is an activity of the Internet Engineering Task Force (IETF), a non-profit organization of loosely affiliated international participants that anyone may associate with by contributing technical expertise. In November 2006, the Internet was included on USA Today's list of the New Seven Wonders.
