Английский язык: Сборник текстов и упражнений. Иваненко Т.И. - 29 стр.

      VII. Think and say:
      A) Speak about access to the Internet; B) What a protocol is; C) Define TCP/IP.




LESSON 11

                               TELEPHONE CONNECTIONS

       A more flexible system is one in which the computer or terminal uses a dial – up connec-
tion over a telephone line. In such cases, you can work anywhere you want as long as you have
access to a phone line.
       To use a dial – up connection, you need a hardware device to convert computer signals to
telephone signals and back again. In technical terms, the computer signal is “digital” and the tel-
ephone signal is “analog». A device that converts from digital to analog is called a modulator. A
device that converts from analog to digital is called a demodulator. When we connect computers
over a phone line, we must be able to send data in both directions. For this, we use a modem, a
“modulator – demodulator”.
       When you buy a modem for your own computer, take into consideration the following
things:
       – The speed of a modem is measured in bits/seconds or bps. An acceptable speed of a
modem is 14, 400 bps. This speed is used only with the services of the Internet, i.e. text informa-
tion, such as e – Mail, teleconferences. For looking through Web sites abundant graphics and
multimedia additions you must buy a modem with the speed over 38, 400 bps. Or 57, 600 bps
(that is four times the nominal speed);
       – It is necessary to take into consideration the choice between an internal and external
modem. The internal modem represents an ordinary extension board inserted into a computer
housing. A modem can be a separate box that attaches to your computer (usually via a “ serial”
cable). The external modem has its own housing and is connected to a computer via a port joint.
       Notice that a dial – up connection requires a modem at each end of the telephone line.

      NOTES

     1. As long as you have access to a phone line – при условии, что вы имеете доступ к те-
лефонной линии
     2. In bits/ second or bps – в бит/с ( скорость передачи в секунду)
     3. Four times the nominal speed – в четыре раза быстрее номинальной скорости
     4. Via a port joint – через разъем порта

      VOCABULARY

      A more flexible system – более гибкая система
      Terminal – терминал; элемент централизованной вычислительной системы , обеспе-
чивающий интерфейс с пользователем и доступ к ресурсам хост-компьютера. Имеет эк-
ран, клавиатуру и, возможно, мышь, похож на персональный компьютер.
      Dial – up connection over a telephone line – соединение с помощью набора номера на
диске через телефонную линию
      To convert computer signals to telephone signals – превращать компьютерные сигналы
в телефонные сигналы
      Modulator – модулятор
      Over – через, по

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