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Data transport through a speedy world
Text A A. Text Study
a. Look at the title. What do you think this reading will be about? Read the text and define its main idea. One hundred years ago people communicated exchanging letters, fifty years ago it was a telephone call, and in the 1980s personal computers and fax machines were the technology du jour (современная). In the telecommunications age, the demand for greater bandwidth, more storage capacity, and accelerated data transport speeds is increasing faster than you can click on your send button. When choosing a transport medium you should consider the amount of bandwidth that is guaranteed (bandwidth is the ability to transport data). Different ranges of bandwidth are necessary for different applications. The most common methods of data transport are telephone lines, wireless communications, the Internet and fiber optics. A standard telephone line can only handle 56k (one k = 1000 bits); most standard wireless systems can give 10Mb of bandwidth. Today’s highest speed on the Internet is 45Mb/sec on major trunk lines, and most Internet users access the Web at around 56K. Fiber has closed to unlimited bandwidth and can be broken up into many streams of light carrying 194 Mb. Since the early 1960s when the first communications satellite was launched, the satellite aerial/wireless industry has exploded. Communications satellites provide a worldwide link-up of radio, telephone and television. The wireless system consists of a receiver and transmitter located at each end of the connecting sites. These transceivers relay information to each other via radio signals. Telephone line is the most commonly used communications device. With today’s transmission of video and data, a standard telephone line has only enough bandwidth to transmit 56 k data and either analog or digital voice. In order to transmit video over telephone lines, a CODEC (a compression / decompression device that breaks up the video and data into packets) is required. As digital trend grows, copper wire utilized for long distances has been replaced by glass cables as thin as strand of hair. Fiber-optic cable offers increased call-carrying capacity, higher speed, and greater transmission quality. The fiber-optic transmission is based on the principle of total internal reflection. Light travels inside the core of the fiber and reflects any light trying to escape from the core. Fiber-optic cable carries information in the form of digital bursts of light, at data rates that are thousands of times greater than those of normal phone lines. The Internet is a network that contains assorted media, computers, and applications. Today the Internet is over-utilized and bandwidth is limited. As the number of online users multiplies, the amount of space on the Web and the bandwidth availability decrease. Internet II, a higher speed network currently being developed, may go a long way towards solving these problems. No matter which mode of transport a consumer chooses, limitations exist in every one of them. It is important to understand how to get the most from a chosen medium.
II. Read the text again carefully and answer the questions. 1. How did people communicate before the advent of personal computers and fax machines? 2. What requirements are increasing in the telecommunications age? 3. What should you consider when choosing a mode of transport? 4. What methods of data transmission do you know? 5. Why has wireless industry exploded since 1960s? 6. What is required to transmit video over telephone lines? 7. What has been replaced by glass cable? 8. What beneficial effects does fiber-optic cable have? 9. What principle is the fiber-optic transmission based on? 10. Why is the Internet over-utilized? 11. What is Internet II? 12. Is there a transport medium without any limitations?
III. Which of the vocabulary units used in paragraphs 1-2 could be regarded as international words? IV. Read the translation of the sixth paragraph. Compare it with the original and say if everything is right. С появлением цифровой связи использование медного провода для передачи данных на близкие расстояния заменили волоконными кабелями толщиной в человеческий палец. Благодаря применению волоконного кабеля увеличился объем передаваемых звонков, скорость и качество передачи. Волоконно-оптическая передача информации основана на принципе частичного внешнего отражения. Свет перемещается по волокну и отражается при попытке выйти за его пределы. Волоконно-оптический кабель передает информацию в виде импульсов в тысячу раз быстрее, чем стандартные телефонные линии.
VI.Find the English equivalents of the following words and word combinations in paragraph 6. Передавать информацию, использовать, волоконно-оптический кабель, цифровой, вспышки света, сердцевина оптического волокна, увеличивать, основываться на чем-либо, отражение.
V. Find the passage about data transmission over telephone lines and translate it into Russian. VII.Choose a passage and read it aloud (1-2 minutes). VIII.Find complex grammar structures in the text and divide them into simple ones. IX. Find out the subject-matter and the means of its secondary expression. e.g. Betty has a temperature. Give her some tablets. X.Find key words, phrases and the topic sentences which express the general meaning of each paragraph best of all. XI. Using the information obtained from the paragraphs make a plan of the text. XII.Speak about various transport media available, their limitations and benefits using key words, phrases, the topic sentences and the plan of the text.
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