Lesson 15

Read the text: Network remote access devices

Network remote access devices are used to connect remote (off-site) users to an organization's network. There are many options available.

A modem is a device that converts data from digital to analog signals so it can travel over the public switched telephone network (PSTN) to its destination. Once the signal reaches its destination, the modem converts it back to digital. As the PSTN was designed to carry voice (analog signals), it is not the best option for carrying data. Digital data networks (DDNs) are replacing the PSTN. DDNs are used to transmit both data and digitized voice. Because of their slow data transmission speeds, modems are no longer used in most business environments.

Integrated services digital network (ISDN) is a switched, high-speed data service. ISDN is an international telecommunications standard for transmitting voice, video, and data over digital lines running at 64 Kbps, and reaches 1.5 Mbps in North America and 2 Mbps in Europe. ISDN uses the same copper telephone lines as modems do, but at a rate approximately five times faster. Furthermore, it is extremely reliable.

A T1 line carries data approximately 60 times faster than a modem on a normal telephone line. The higher speed and extreme reliability make this a popular choice for many medium- to large-sized businesses. T1 lines can handle hundreds of users simultaneously for general browsing. However, it cannot handle that many users simultaneously downloading large files, such as MP3 files or video files. For very large companies, T1 lines may not be sufficient.

A cable modem is a device used to connect a computer to a coaxial cable, such as the kind used for cable television, in order to access online services. This device modulates and demodulates signals like a conventional modem. In addition, a cable modem functions like a router designed for installation on cable television networks. The most popular application for cable modems is high-speed Internet access, which provides much faster service than standard telephone-line modems, thus enabling users to access streaming audio, video, and other services.

Mobile telephones, laptop computers, and handheld computers are so affordable that they have become a part of everyday life for many people and businesses around the world. Advances in wireless technology have made it possible for people to access networks without having to physically connect to the network through cables. For example, it is not uncommon for business travelers to access networks on their wireless fidelity (Wi-Fi)-enabled laptop PCs or handheld computers while waiting at an airport.

Bluetooth is a wireless standard developed by a group of electronics manufacturers to allow any electronic device—such as computers, cell phones, keyboards, and headphones—to find and connect to other devices without any direct action from the user. The devices find one another and transmit data without any user input at all. Because Bluetooth technology is inexpensive and does not require the user to do anything special to make it work, it is gaining wide use around the world.

Wireless products are now affordable and very reliable. With wireless connections, it is possible for people to move around while connected to a network. This could be very useful in environments such as hospitals, so that health care professionals could access patient records from various locations around the campus. Many home and small-business users also use wireless networks to avoid the need to route twisted-pair wiring around their premises. In fact, domestic, small-office, and home-office networking accounts for most of the wireless Ethernet equipment sales in the United States.

In summary, computers connected with communications networks improve productivity and profitability by enabling people and organizations to develop closer relationships with coworkers, customers, business partners, and other people in general.

Exercise 1. Learn the following words and word-combinations:

Destination, browsing, in order to, affordable, advances, fidelity

Exercise 2. Answer the questions:

1) What is a modem?

2) Why are modems no longer used in most business environment?

3) What can T1 lines handle?

4) What are the advances of wireless technology?

5) What is the function of a cable modem?

Exercise 3. Find derivatives to the following words:

1) afford; 2) possible; 3) connect; 4) common; 5) locate; 6) use; 7) equip; 8) communicate; 9) improve; 10) profit

Exercise 4. Find in the text and give English equivalents to the following Ukrainian words:

1) віддалений; 2) пристрій; 3) місце призначення; 4) перетворювати; 5) приблизно; 6) надійність; 7) одночасно; 8) однак; 9) достатня кількість; 10) розміщення

Exercise 5. Compose a story on one of the topics (up to 100 words):

1) Modems.

2) T1 lines.

3) Wireless Technology.