Telecommunications

A Handbook for Educators

Resa Azarmsa

• Publisher: Routledge
• Year: 2013
• ISBN:
  9781135520731
• Edition: 1
• Topic: Education
• Subtopic: Education General

The objective of this book is to provide a comprehensive introduction to telecommunications and their applications in teaching and learning. It contains up-to-date information about telecommunications, including the latest hardware and software. It discusses the most recent developments in computer networking and how to apply them creatively in the classroom and the school. There is an in-depth discussion of teleconferencing as a way to bring cost-effective instructional material to students. The book also explores distance learning and how it can be expanded to include the home and office as well as the school. There is a detailed presentation on how to ensure computer security in schools to protect records, grades, and other sensitive data. Practical applications and examples are given where appropriate. A directory of on-line educational databases, a lengthy glossary, and an index are included.

Chapter One

An Overview of Telecommunications

Introduction

During the last five centuries, technology has revolutionized communications. From the first printing press to modern computer technology, developments in communications have constantly changed human society. Instantaneous communication around the globe, once a dream, is a reality. The ongoing communications revolution has brought us to the brink of a science-fiction future.

Rapid communications has done much to alter the structure of society. Arthur Clarke, the author of 2001: A Space Odyssey and 2010: Odyssey Two, believes that the communications revolution affects the way we think, work, play, do business, and relate to one another. The concept of a “global family,” “electronic village,” or the “universal village,” through communications technology, now links nations electronically.

Electronic meetings, convened across a nation or around the world, can be beneficial as well as cost effective. Every day hundreds of teleconferences are held in different sites. Every day, thousands of interested groups share information, asking questions via telephone line, eliminating the need to travel a long distance or, in some instances, even to leave the office. Soon after the first communication satellite, Telstar 1, was launched into geosynchronous orbit in July 1962, a multi-billion dollar industry began.

What Is Telecommunications?

Telecommunications is defined as a process of transmitting information over a distance by an electrical or electromagnetic system. This information may take the form of voice, data, image, or message. Electromagnetic transmission systems include telephone lines, cables, microwaves, satellites, and light beams.

Voice communication is known as telephony. Voice communication systems transmit spoken words over telephone networks in the form of electrical energy that varies in amplitude with the sound variations being transmitted. These systems include public and private, local and long distance services.

Data communications is the transmission of data from a computer in one location to another computer in other location. The data is transmitted in coded form over electrical transmission facilities.

Written message systems such as Telex send messages in data form, i.e., telegram and teletypewriter. They are message systems because they are used to transmit messages rather than conversation. Message systems provide a faster alternative to the postal service.

Image or facsimile (FAX) systems transmit text, pictures, diagrams, etc., via a telecommunication system to a remote location where a hard copy of the transmitted material is reproduced.

Telematics is described as merging of telecommunications with computers and television. The word compunication describes the same meaning. The marriage of telecommunications and computer technology has made the information age possible. The marriage has produced a number of offspring, including teleconferencing, telemarketing, telecommuting, telejournalism, telemedicine, and telelearning.

Telecommunications and Society

Telecommunications evolved as a branch of electronics, specifically, electrical engineering. As with most disciplines, electronics has its own special language. The technical aspects of the language, oriented toward electrical circuitry, often deter laypeople from studying telecommunications. However, the increasing use of electronic information handling has made it necessary for business persons—and many others as well—to understand the terminology and underlying principles of telecommunications.

Recognizing the need for people to be familiar with computers, many schools and colleges are requiring students to develop computer literacy. Telecommunications is no less important. As we progress toward “the paperless office,” “the cashless society,” and “the home office,” persons from all walks of life are finding that a knowledge of the language and concepts of telecommunications is becoming a must. The intention of this textbook is to describe the basic terminology and concepts of telecommunications in nontechnical language so that persons with no special training or background in the field can understand them.

Modern society is rapidly becoming an information-based society, and telecommunications is central to this development. The availability of nearly “instant information” made possible by telecommunications technology is changing our jobs, our business organizations, our schools, and our personal lives.

Newspapers, threatened by increased competition and decreased profits and readership, are searching for new ways to attract and retain readers and advertisers as the print media move, however timorously, into the increasingly electronic decades of the information age.

Newspapers are trying to take advantage of new communications technologies and use information they gather every day at great expense and now use only once. They want to cement a seven-day-a-week relationship with readers by becoming more useful and more interesting to a generation accustomed to the accessibility and excitement of television, computers, and video games. With the help of telecommunications technology, newspapers want to reverse a decline in the numbers of Americans reading a newspaper every day.

Many experts in communications technology envision a personalized electronic newspaper available by some combination of computer and television set, early in the next century; in the meantime, some newspapers are experimenting with a variety of intermediate technologies. More than a dozen newspapers have tried sending small editions to selected subscribers by FAX, and others are experimenting with various versions of videotex—newspapers by computer.

For example, Rocky Mountain News, published in Denver, Colorado, gives subscribers the computer software necessary to receive—free of charge—a separate edition of the daily paper, updated frequently and available 24 hours a day by computertelephone hookup.

The Fort Worth Star-Telegram, published in Texas, another daily newspaper, offers stories from the daily paper and from national news services to the residents on StarText—a computer service that enables users to get an early look at the next day’s classified ads, as well as make travel reservations, exchange electronic messages, and access a “reference room” that includes book and movie reviews and gardening tips via telephone line.

The Atlanta Journal and Atlanta Constitution have 250 special telephone lines for readers who want sports scores, news updates, restaurant reviews, movie schedules, soap opera updates, and stock, weather, and traffic reports.

Many newspapers have established 900 telephone numbers that require users to pay a fee for recorded information. The callers can get information on stock market reports, crossword puzzle clues, horoscopes, weather reports, restaurant reviews, soap opera updates, sports scores, recipes, as well as travel, entertainment, and real estate information.

Telecommunications in Business Organizations

Information is the lifeline of modern business; it provides the basis for all business activities. Managers apply judgment to the information available to make their decisions—decisions that have a strong impact upon the success of any enterprise. Recognizing their dependency upon information, businesses have begun to focus on the management of this vital resource.

The present trend in information management is to establish formal management information systems (MIS) to make information immediately available to various levels of management throughout an organization. Some companies have created separate Management Information System Departments to coordinate the flow of information throughout the organization. Telecommunications plays a key role in these departments.

Telecommunications makes possible the technique of distributed processing, which links intelligent terminals to central computer processing facilities through the use of communication lines. Telecommunications also makes possible the instant availability of information from a centralized database (facts arranged in computer files for access and retrieval) within an organization. With a database, information can be shared among the various departments of an organization and among remotely located branches. Thus, many different people with different job responsibilities can access the database from terminals, often referred to as workstations, located in their work areas.

Some companies have established industry-wide databases that can be accessed from virtually anywhere via telecommunication lines. Companies that maintain database services offer access to their database for a subscription fee. These information centers are available for many industries and professions, including transportation, banking, investments, publications, law, and medicine. The databases are protected from unauthorized access by security measures that require user identification via a password or series of passwords.

WESTLAW, one commercial database system, was created by West Publishing Company, a publisher that has served the legal profession for over a century. The WESTLAW system connects remote terminals located in law offices, courts, and government agencies with a centralized database by means of telephone lines. Users enter commands or inquiries at a typewriter-like keyboard; responses are displayed on the cathode ray tube (CRT), or terminal screen. Users can record information appearing on the screen on paper by means of an associated printer. The system is protected from unauthorized access by a multistep sign-on procedure.

This system offers legal research capabilities that permit a lawyer to scan large numbers of cases and identify relevant ones in a few seconds. The system has two basic advantages:

1. speed in finding the research material

2. search capabilities not possible using books

The system’s unique search capabilities allow users to access case summaries using terms other than those indexed in law books. For example, users can locate a case by entering almost any term associated with that court decision—names of judges, witnesses, companies, and unusual nonlegal terms.

WESTLAW is constantly being updated; as new cases are reported, they are added to the database. The system has improved legal research by allowing users to accomplish more research in less time and by providing new search capabilities.

Many organizations are using telecommunications effectively to enhance their services or to provide new services. Additionally, there are industries whose very existence depends upon telecommunications. Among these are airlines, banking, investments, credit card services, and hotel/motel reservation systems.

Airlines

All major airlines in the United States have computerized systems for handling reservations. To make a reservation, a person dials a local telephone number that connects to a regional reservation center, probably located in a distant city. The regional center is linked to a national center by telephone lines. The reservation clerk keys in the desired destination on a remote terminal to access the central computer and obtain information about possible flights. Information displayed on the terminal screen lists the flights on which seats are available and the fares. When the traveler selects a flight, the clerk enters the details of the booking into the system, and the computer’s seat inventory is updated. The cancellation of reservations also is handled automatically; the computer cancels the reservation and adds to the number of seats available on the flight. In addition, the computer keeps a waiting list of passengers desiring reservations and their telephone numbers. Reservation systems are interlinked with those of other airlines so that connecting flights can be booked.

Telecommunications also permits computer operators to monitor air traffic from control towers. A computer system identifies each approaching plane and tracks its altitude and speed, enabling air traffic controllers to give directions for landing.

Banking

Another major industry dependent upon telecommunications technology is banking. Banks use remote terminals and telecommunication lines to update customers’ accounts. Tellers located either at main offices or branch offices insert the customer’s passbook into a computer terminal and key in relevant information; the terminal prints the entry in the passbook and transmits the information to update the central computer files.

In some cases, customers can use their push-button telephones to perform certain banking transactions such as paying bills, transferring funds, and determining their bank balances. The telephone functions as an input terminal when it is connected to the bank’s central computer by telephone lines. The user communicates with the computer by entering appropriate codes on the telephone key-pad.

Banks also use telecommunication lines to provide automatic teller service. Automatic teller terminals are connected to the bank’s central computer via communication lines. To process a transaction, the customer inserts an identifying bank card into the terminal and keys in a personal identification number. After the computer performs appropriate checks on the customer’s identity and account status, the customer keys in a transaction code, and the machine completes the transaction. Automatic tellers are located in shopping malls, supermarkets, and places of employment as well as on bank premises. Many of these terminals accommodate bank cards issued by cooperating banks, credit unions, and savings and loan associations. Automatic tellers offer the convenience of 24-hour operation for the most frequently used services such as deposits, withdrawals, and payments to utilities and credit card accounts.

Many banks now participate in shared networks: a bank network system in one area of the country interconnects to another bank network in another area. It should be noted that banks also have to talk between themselves. Some networks available for this type of communication are:

• SWIFT (Society for Worldwide Interbank Financial Telecommunications)

• MINTS (Mutual Institution National Transfer System)

• FED WIRE (Federal Reserve Bank Telecommunications Network)

• BANK WIRE (Interbank Network)

These networks are used for transferring information between banks. Banks also create private networks and interconnect them for use with the general public. Wholesale electronic funds transfer between banks. By contrast, private bank networks involve retail electronic funds transfer for use by the general public and/or customers of each individual bank. A bank’s network for its checking/savings branch offices, ATMs, POS terminals, home banking, and the l...