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I. Read and translate the text.



Computer network

A computer network or data network is a telecommunications network which allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections (network links). Data is transferred in the form of packets. The connections between nodes are established using either cable media or wireless media. The best-known computer network is the Internet.

Network computer devices that originate, route and terminate the data are called network nodes.[1] Nodes can include hosts such as personal computers, phones, servers as well as networking hardware. Two such devices are said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other.

Computer networks differ in the transmission media used to carry their signals, the communications protocols to organize network traffic, the network's size, topology and organizational intent. In most cases, communications protocols are layered on (i.e. work using) other more specific or more general communications protocols, except for the physical layer that directly deals with the transmission media.

Computer networks support applications such as access to the World Wide Web, shared use of application and storage servers, printers, and fax machines, and use of email and instant messaging applications.

A computer network, or simply a network, is a collection of computers and other hardware components interconnected by communication channels that allow sharing of resources and information. As of 2015 computer networks are the core of modern communication.

Computer networking may be considered a branch of electrical engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of the related disciplines.

A computer network facilitates interpersonal communications allowing people to communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing. Providing access to information on shared storage devices is an important feature of many networks. A network allows sharing of files, data, and other types of information giving authorized users the ability to access information stored on other computers on the network. A complex computer network may be difficult to set up. It may be costly to set up an effective computer network in a large organization

II. Retell the text.

Unit X.

I. Read and translate the text.

The World-Wide Web

The years 1989-96 was another pivotal period for what was effectively known as the Internet, stressing the fact that the original ARPANET had been followed by myriad of fast growing sub-networks operating in the U.S. and internationally. In 1989 the ARPANET was decommissioned and in April 1995 the NSFNET reverted back to a pure research network, leaving a number of private companies to provide Internet backbone connectivity. At the same time the number of hosts as well as the network traffic grew at an enormousirate.

The veritable explosion in network use, apart from the fact that the personal computer became a household item in the same span of time, can be attributed to the result of a research proposal submitted to the funding authorities of the European Laboratory for Particle Physics in Switzerland, CERN (a French abbreviation for Conseil Europeen pour Ia Recherche Nucleaire). The title was “WorldWideWeb: Proposal for a HyperTextProject,” and the authors were Tim Berners-Lee and Robert Cailliau.

The World-Wide Web (also known as the WWW or Web) was conceived as a far more user-friendly and navigationally effective user interface than the previous UNIX-based text interfaces. The communications protocol devised for the WWW was termed HTTP (HyperText Transfer Protocol), hypertext being a navigational tool, linking data objects, be it text or graphics, together by association in what is effectively a web of pages, hence the use of the term “World-Wide Web.” Berners-Lee and Cailliau describes the process as follows: “A hypertext page has pieces of text which refer to other texts. Such references are highlighted and can be selected with a mouse… When you select a reference, the browser [the software used to access the WWW] presents you with the text which is referenced: you made the browser follow a hypertext link.”

The WWW prototype was first demonstrated in December 1990, and on May 17, 1991 the WWW began to work due to granting HTTP access to a number of central CERN computers. As soon as browser software became available for the more common operating systems such as Microsoft Windows and Apple Macintosh, this new tool was immediately picked up by the Internet community.

The World-Wide Web, the simplicity of Internet access for private individuals, as well as the increasing user-friendliness of the software necessary to master the Internet protocols contributed to the meteoric rise of network use in the 1990s.

Browsing through the original WWW proposal reveals an irony very characteristic to the development of the Internet, in the face of its author’s assertion that “the project will not aim to do research into multimedia facilities such as sound and video.” In 1996 the present and future of the Internet, and the WWW in particular, points to a convergence of media types, and multimedia has indeed become the catch phrase of the day. Despite serious limitations in contemporary network capacity as far as to sound and video, new technologies constantly enable the increase of interactive network experiences. This development is supplemented by a constant innovation in hardware; today’s Internet backbones transmit data packets at a speed up to 200 megabits per second (by comparison, the NSFNET backbone of 1986 ran at the blazing speed of 56 kilobits per second). Today the modems of most Internet users run at a speed of 28.8 kbit/s and a digital connection can deliver at a speed of up to 128 kbit/s, but the possibility of using the fiber optic cables bringing cable TV to millions of homes, for Internet data transmission opens up for private connections running at a speed of up to 10 Mbit/s. Another new technology, ASDL, promises to use the existing telephone copper wires for even higher transmission speeds.

But what will these network technologies deliver to the Internet user? In 1996 commercial Internet hosts have overtaken educational and governmental applications and these commercial interests clearly consider the Internet, and the WWW in particular, as a vehicle for online advertising and commerce. Hence the Net user of today can be described as a consumer. The Internet is still a powerful medium for communication, and has in many ways fulfilled the vision of interactive computing which fueled J.C.R. Licklider’s imagination, but it remains to be seen whether it will be the democratizing medium of the 21st century, or merely become another static-filled television channel.

Notes:

Household item-предмет домашнего обихода

Span of time-промежуток времени

To submit a proposal-высказать предложение

Catch phrase-фраза дня

 

COMPREHENSION CHECK

 




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