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COMPUTER COMMUNICATIONS
1. The present status of telecommunications is a result of a long evolution through more than a hundred years. It is interesting to note that the old telegraph system used digital transmission. When, many years later, telephony was introduced, analogue transmission was used. Telex, on the other hand, worked with a digital technique while video transmission in principle uses analogue transmission. Data communication is digital and a transition is now taking place where all services, voice, text, data and picture—will be integrated in a basic digital network. This digital network will be an ideal carrier of data communications and will promote the growth of such communications.
2. The development of data communications depends, to a great extent, on the development of data processing. So far, all the signs indicate a trend towards remote data processing which means a greater usage of data communications services.
3. A number of new text services have been, or will be, introduced shortly.
Firstly, a lot of interest has been shown in Teletex which is already being introduced in some countries. Teletex is an international service enabling subscribers to exchange correspondence on an automatic memory to memory basis, via telecommunications networks. As a successor to Telex, it will use specially adapted word processors and electronic typewriters and enable a 3-page A4 letter to be sent almost instantaneously from one end of the country to the other.
4. The Telefacsimile service is well established, though faster and more advanced systems (Group 4 types) will be introduced shortly. This service provides for the transmission and reproduction of still pictures and printed matter.
Videotex is a service enabling a subscriber to obtain information over the public switched telecoms network (PSTN) for presentation in alphanumeric and/or graphic form on a VDU (visual display unit) —usually a specially adapted TV receiver. This service is marketed under different names in different countries. Videotex subscribers may choose to have an additional service—electronic mailbox enabling them to send messages directly and instantaneously to one another. The UK viewdata system, which is an interactive service, should not be confused with Teletext, a one-way innovation service which TV companies broadcast.
5. Technically it will be possible to integrate various types of telecommunications networks (private and public, data and telephony) to form an Integrated Services Digital Network (цифровая сеть с комплексными услугами . ISDN is a wide band integrated services local communications system, offering the subscriber the complete spectrum of telecommunications services, including a new video telephone service as well as radio and TV broadcasts, all transmitted via optical fibre cables.
6. Despite this development towards ISDN, a number of specialized networks will have to live side by side for many years to come. From the customer's point of view, it is therefore essential that networks and services are compatible. It should be possible to use one and the same terminal for different devices and to send traffic over different networks. The question is how can this be realized? Could an integrated network be developed?
VI. Say whether the following statements are true or false.
| The system of Telecommunications is not evolving nowadays. | |
| The old telegraph transmitted messages in digital form. | |
| Data communication is digital and shortly all services will be integrated in a basic digital network. | |
| Teletex is a local service enabling subscribers to exchange messages via faxes. | |
| Teletex will use adapted techniques but the service will be very slow. | |
| Telefacsimile service is developing now. It provides instant transmission and reproduction only of images. | |
| Videotex service enables a subscriber to obtain information by means of a specially adapted TV receiver. | |
| A number of other techniques will develop as well as ISDN in the nearest future. |
VII .Choose the best continuation for each of the following beginnings to match the contents of the text.
| We are living in an age… | |||
| a | of digital techniques | ||
| b | of quickly changing and developing communication technologies | ||
| c | of analogue information transmission | ||
| The development of data communication depends on the development of… | |||
| a | the telegraph | ||
| b | data processing | ||
| c | telefaxes | ||
| Digital network will be an ideal carrier of… | |||
| a | voice and images | ||
| b | data communications | ||
| c | additional services | ||
| Teletex is… | |||
| a | an international service for exchange correspondence via telecommunications networks | ||
| b | a local communications system | ||
| c | a service providing data processing | ||
| The Telefacsimile service… | |||
| a | makes an interactive service | ||
| b | provides transmission and reproduction of still images and printed matter | ||
| c | enables a 3-page A4 letter to be sent almost instantaneously | ||
| Videotex service… | |||
| a | provides an electronic mailbox to a subscriber | ||
| b | integrates various types of telecommunications | ||
| c | includes a video telephone service | ||
| While developing ISDN, it’s essential that… | |||
| a | a customer has a terminal | ||
| b | specialized networks will also develop | ||
| c | networks and services are compatible |
VIII. Choose the right English word or word combination in the box for the Russian fragments in brackets.
| techniques | means | alphanumeric | to replace |
| integrated | data | instantaneously | printed |
| available | adapted | widespread | still |
| including | enables | numerous | transmit |
| Modern electronic systems (передают) information (незамедлительно) from a sender to a receiver. | |
| The (широко распространенное) adoption of new communication (оборудование) has altered the communication process. | |
| All services, voice, text and (данные) will be (объединены) in a digital network. | |
| Computer communications use specially (приспособленные) word processors and electronic typewriters. | |
| The telefax service (предоставляет возможность) to transmit and reproduce (неподвижные) pictures and (печатные) matter. | |
| Videotex presents information in (буквенно-цифровой) or graphic form. | |
| E-mail being very fast and convenient is beginning (заменять) slower paper media. | |
| ISDN offers a subscriber (многочисленные) telecommunication services (включая) a new video telephone service. | |
| Large-scale networks are becoming (доступный) as a (средства) of transmitting messages rapidly and worldwide. |
IX. Look through the text again and answer the following questions.
| What forms did telecommunications evolve into through more than a hundred years? | |
| What will be an ideal carrier of data communications? | |
| Teletex is an international service enabling to exchange correspondence via satellite service, isn’t it? | |
| Does teletex or telefacsimile service use adapted word processors and electric typewriters? | |
| Why is electronic mail replacing paper media nowadays? | |
| What is essential for all networks and services? |
X. Use the diagram below and speak about possible development of integrated networks.
Part B
I. Look through the English words and their Russian equivalents facilitating reading text B.
| supervisory | /"sju:pq'vaIzqrI/ | наблюдательный, контролирующий |
| maintain | /meIn'teIn/ | поддерживать, сохранять |
| upload | /AplqVd/ | загрузка |
| downstream | /'daVnstri:m/ | смещение по ходу ленты |
| proprietary | /prq'praIqt(q)rI/ | собственный, патентованный |
| assign | /q'saIn/ | определять, назначать |
| affordable | /q'fO:dqbl/ | возможный, допустимый |
| twisted pair | /'twistId'pFq/ | витая пара |
| splitter | /'splItq/ | расщепитель, приемный распределитель |
| premises | /'premIsIz/ | помещение, здание, дом |
| upgrade | /Ap'greId/ | улучшать |
| bandwidth | /"bxnd'wIdT/ | ширина полосы частот |
| download | /daVn'lqVd/ | загрузка |
| shield | /"Si:ld/ | экран, защита |
II. Define the meaning of the “X” word:
| supervise: supervisory = x: контролирующий |
| provide: provision = обеспечивать: x |
| maintain: maintenance = поддерживать: x |
| afford: affordable = x: допустимый |
| twist: twisted = x: переплетенный |
| connect: connector = x: соединитель |
| vary: variable = менять, разнообразить: x |
| require: requirement = требовать: x |
| install: installation = устанавливать: x |
| assign: assignment = предоставлять: x |
III. Find in the list the following parts of speech:
a) nouns
| exist, existence, existing, existed, existent | |
| alternative, alternatively, alternator, alternation | |
| frequent, frequency, frequently, frequentative | |
| converse, conversable, conversation, conversational |
b) adjectives
| supervise, supervision, supervisory, supervised | |
| cell, cellular, cellulite, cellulose | |
| avail, available, availability, availably | |
| digit, digitalization, digital, digitize |
c) verbs
| splitter, split, splitting, splitted | |
| utility, utilize, utilized, utilization | |
| additional, addition, add, additionally | |
| significance, significant, signify, signification |
IV. Complete the sentences with the following words in the box. Translate completed sentences into Russian.
| require | independent | twisted-pair | installation |
| utilized | additional | equipment | channel |
| digital | upgrading | available | upload |
| copper | supervisory | affordable |
| A common ISDN interface standard has a (цифровой) communications line consisting of three (независимый ) channels. | |
| The Data (канал) is used to carry signalling and (контролирующий) information to the network. | |
| Satellite systems (требуют) the use of a modem to maintain the (загрузка). | |
| Cable companies can also offer (допустимый) broadband services over (медный) coaxial or fibre networks. | |
| DSL technology allows the full bandwidth of the copper (витая пара) telephone cabling to be (использованный). | |
| This involves (дополнительный) hardware and (установка). | |
| The telephone company’s (оборудование) might need (улучшение). | |
| DSL-based services can be made (допустимый) to the customer at extremely competitive prices. |
V. Read the text “Broadband communications” and say what communications services are available to customers.
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