Satellite Connection

Getting the Internet connection from a satellite is really not all that different from getting TV signals from one. In both cases data is being sent from the satellite to a user's equipment and then translated and decoded. One major limitation of satellite technology is that it can only send data from the satellite to a user's receiver – not the other way. To get around this problem, a separate ISP connection is needed to send data to the Internet, typically over an analog modem. This connection works in conjunction with the satellite feed. As information is requested via the modem line, data are sent back via the satellite. Since most Internet users need high bandwidth from the Web, downstream (typically Web pages and file downloads), and less bandwidth going to the Web, upstream (typically link requests), this scenario of sending upstream data over a standard modem line and downstream data over the high-bandwidth satellite feed has been effective. The newest satellite technology allows for two-way communications and higher upstream bandwidths. A satellite return channel can be added for traffic bound for the Internet. The upload speeds through this satellite return channel may peak at 128 kbps. Download speeds with this system are up to 400 kbps. Satellite technology has one strong advantage over cable modems and DSL: accessibility. For many it is today’s only high-speed option. It can reach areas that are otherwise difficult to establish contact with. The infrastructure exists to provide 400 kbps downstream bandwidth to almost anyone with a 21” satellite dish. It is eight times faster than fastest analog telephone modems and three times faster than ISDN. However, it is not as fast as cable modems or DSL services, which both can provide more than megabits of bandwidth. Also, cable and DSL access methods are cheaper. Equipment required for satellite connection includes installation of a mini-dish satellite receiver and a satellite modem. Like cable modem systems, satellite provides a “shared bandwidth” pipe. This means that download performance may vary depending upon other users of the satellite transponder. Another potential problem can be associated with severe weather. In severe snowstorms and heavy rain, users may experience signal fade.

The general rule about the Internet connection is the faster, the better. The bandwidth and transfer rate determine how quickly pictures, sounds, animation and video clips will be downloaded. Since multimedia and interactivity make the Internet such an exciting tool for information sharing, the speed is the key. Dial-up access provides an easy and inexpensive way for users to connect to the Internet, however, it is a slow-speed technology and most users are no longer satisfied with dial-up or ISDN connections. Fortunately, the broadband access, we once dreamed of, is now possible with TV cable, DSL and satellite links.

Task 1. After reading the text answer the questions:

1. How many bits are there in a byte?

2. How many ways of connecting to the Internet are mentioned in the text?

3. What is the main disadvantage of Dial-up connection?

4. Is ISDN connection available everywhere?

5. What is the main difference between ADSL and SDSL?

6. What’s the difference between upstream and downstream bandwidth?

7. What are the advantages and disadvantages of each type of the Internet connection?

8. What is a modulator? A demodulator?

9. What kind of Internet connection would you choose?

Task 2. Find in the text English equivalents to the following:

1. пропускная способность 2. провайдер 3. зависать 4. загружать файл 5. устанавливать оборудование 6. недоступный 7. низкая скорость 8. ограничение соединения 9. локальная сеть 10. спутниковая тарелка 11. цифровая сеть с интегрированным сервисом 12. подключиться к Интернету 13. установить временное соединение 14. передавать информацию 15. сервер, клиент 16. обеспечивать централизованное хранение программ и информации 17. беспрводное соединение 18. доступ в Интернет при помощи кабельного модема

19. безопасность сети 20. получить доступ к содержимому сервера 21. передавать по телефонным линиям 22. скорость передачи данных 23. ассиметричная цифровая абонентская линия 24. скорость доступа в Интернет 25. преобразовывать 26. преобразование 27. отправитель 28. получатель 29. преобразовывать аналоговый сигнал в цифровой 30. входящий поток информации 31. исходящий поток информации 32. наивысшие скорости 33. поминутная тарификация 34. дорогая установка 35. соединение установлено 36. скорость соединения падает

Task 3. Translate the sentences into English using vocabulary from the text.

1. Большинство людей с кабельным телевидением имеют возможность доступа в Интернет при помощи кабельного модема.

2. Скорость, с которой информация передается от отправителя к получателю в сети, называется скоростью передачи данных.

3. Это преобразование выполняется модемом – устройством, которое модулирует (преобразует в аналоговый сигнал) и демодулирует (преобразует аналоговый сигнал в цифровой).

4. Эти типы подсоединений не везде доступны.

Task 4. Construct sentences using fragments from A and B.

A. 1. Many people use some type of non-Internet mail service that...

2. What you should understand is that...

3. We want you to be able to ...

4. The computer or terminal uses a dial-up connection ...

5. To use dial-up connection, you need ...

6. A device that converts from digital to ...

7. A device that converts from analog to ...

8. The speed of a modem is ...

9. It is necessary to take into consideration the choice between ...

10. The external modem has its own ...

B. a. ... over a telephone line.

b. ... analog is called a modulator.

3. ... while mail and Usenet are important, they are not every­thing.

4. ... can exchange messages with the Internet.

5. ... use a computer that has a full TCP/IP connection with the Internet.

6. …a hardware device to convert computer and telephone signals.

7. …digital is called demodulator.

8. …housing and is connected to a computer via a port joint.

9. … measured in bits/second or bps.

10. …an internal and external modem.

Extra

• http://www.bbc.co.uk/webwise/topics/using-the-web/getting-connected

• http://www.bbc.co.uk/webwise/topics/using-the-web/using-a-browser/