Telecommunications

Telecommunications

The transmission of words, sounds, images, or data in the form of electronic or
electromagnetic signals or impulses. Transmission media include the telephone
(using wire or optical cable), radio, television, microwave, and satellite. Data
communication, the fastest growing field of telecommunication, is the process of
transmitting data in digital form by wire or radio. Digital data can be
generated directly in a 1/0 binary code by a computer or can be produced from a
voice or visual signal by a process called encoding. A data communications
network is created by interconnecting a large number of information sources so
that data can flow freely among them. The data may consist of a specific item of
information, a group of such items, or computer instructions. Examples include a
news item, a bank transaction, a mailing address, a letter, a book, a mailing
list, a bank statement, or a computer program. The devices used can be computers,
terminals (devices that transmit and receive information), and peripheral
equipment such as printers (see Computer; Office Systems). The transmission line
used can be a normal or a specially purchased telephone line called a leased, or
private, line (see Telephone). It can also take the form of a microwave or a
communications-satellite linkage, or some combination of any of these various
systems.

Hardware and Software

Each telecommunications device uses hardware, which connects a device to the
transmission line; and software, which makes it possible for a device to
transmit information through the line.

Hardware

Hardware usually consists of a transmitter and a cable interface, or, if the
telephone is used as a transmission line, a modulator/demodulator, or modem. A
transmitter prepares information for transmission by converting it from a form
that the device uses (such as a clustered or parallel arrangement of electronic
bits of information) to a form that the transmission line uses (such as, usually,
a serial arrangement of electronic bits). Most transmitters are an integral
element of the sending device. A cable interface, as the name indicates,
connects a device to a cable. It converts the transmitted signals from the form
required by the device to the form required by the cable. Most cable interfaces
are also an integral element of the sending device. A modem converts digital
signals to and from the modulated form required by the telephone line to the
demodulated form that the device itself requires. Modems transmit data through a
telephone line at various speeds, which are measured in bits per second (bps) or
as signals per second (baud). Modems can be either integral or external units.
An external unit must be connected by cable to the sending device. Most modems
can dial a telephone number or answer a telephone automatically.

Software

Among the different kinds of software are file-transfer, host, and network
programs. File-transfer software is used to transmit a data file from one device
to another. Host software identifies a host computer as such and controls the
flow of data among devices connected to it. Network software allows devices in a
computer network to transmit information to one another.

Applications

Three major categories of telecommunication applications can be discussed here:
host-terminal, file-transfer, and computer-network communications.

Host-Terminal

In these types of communications, one computerthe host computeris connected to

one or more terminals. Each terminal transmits data to or receives data from the
host computer. For example, many airlines have terminals that are located at the
desks of ticket agents and connected to a central, host computer. These
terminals obtain flight information from the host computer, which may be located
hundreds of kilometers away from the agent’s site. The first terminals to be
designed could transmit data only to or from such host computers. Many terminals,
however, can now perform other functions such as editing and formatting data on
the terminal screen or even running some computer programs. Manufacturers label
terminals as “dumb,” “smart,” or “intelligent” according to their varying
capabilities. These terms are not strictly defined, however, and the same
terminal might be labeled as dumb, smart, or intelligent depending upon who is
doing the labeling and for what purposes.

File-Transfer

In file-transfer communications, two devices are connected: either two computers,
two terminals, or a computer and a terminal. One device then transmits an entire
data or program file to the other device. For example, a person who works at
home might connect a home computer to an office computer and then transmit a
document stored on a diskette to the office computer. An outgrowth of file
transfer is electronic mail. For example, an employee might write a document
such as a letter, memorandum, or report on a computer and then send the document
to another employee’s computer.

Computer-Network

In computer-network communications, a group of devices is interconnected so that
the devices can communicate and share resources. For example, the branch-office
computers of a company might be interconnected so that they can route
information to one another quickly. A company’s computers might also be
interconnected so that they can all share the same hard disk. The three kinds of
computer networks are local area networks (LAN), private branch exchange (PBX)
networks, and wide-area networks (WAN). LANs interconnect devices with a group
of cables; the devices communicate at a high speed and must be in close
proximity. A PBX network interconnects devices with a telephone switching
system; in this kind of network, the devices must again be in close proximity.
In wide-area networks, on the other hand, the devices can be at great distances
from one another; such networks usually interconnect devices by means of
telephone.

Telecommunication Services

Public telecommunication services are a relatively recent development in
telecommunications. The four kinds of services are network, information-
retrieval, electronic-mail, and bulletin-board services.

Network

A public network service leases time on a WAN, thereby providing terminals in
other cities with access to a host computer. Examples of such services include
Telenet, Tymnet, Uninet, and Datapac. These services sell the computing power of
the host computer to users who cannot or do not wish to invest in the purchase
of such equipment.

Information-Retrieval

An information-retrieval service leases time on a host computer to customers
whose terminals are used to retrieve data from the host. An example of this is
CompuServe, whose host computer is accessed by means of the public telephone
system. This and other such services provide general-purpose information on news,
weather, sports, finances, and shopping. Other information-retrieval services
may be more specialized. For example, Dow Jones News Retrieval Services provide
general-purpose information on financial news and quotations, corporate-earning
estimates, company disclosures, weekly economic survey updates, and Wall Street
Journal highlights. Newsnet provides information from about 200 newsletters in
30 different industries; Dialog Information Services, BRS Bibliographic
Retrieval Services, and Orbit Information Retrieval Services provide library
information; and Westlaw provides legal information to its users. See Database.

Electronic-Mail

By means of electronic mail, terminals transmit documents such as letters,
reports, and telexes to other computers or terminals. To gain access to these
services, most terminals use a public network. Source Mail (available through
The Source) and EMAIL (available through CompuServe) enable terminals to
transmit documents to a host computer. The documents can then be retrieved by
other terminals. MCI Mail Service and the U.S. Postal ECOM Service (also
available through The Source) let terminals transmit documents to a computer in
another city. The service then prints the documents and delivers them as hard
copy. ITT Timetran, RCA Global Communications, and Western Union Easylink let
terminals send telexes to other cities.

Bulletin-Board

By means of a bulletin board, terminals are able to facilitate exchanges and
other transactions. Many bulletin boards do not charge a fee for their services.
Users of these services simply exchange information on hobbies, buy and sell
goods and services, and exchange computer programs.

Ongoing Developments

Certain telecommunication methods have become standard in the telecommunications
industry as a whole, because if two devices use different standards they are
unable to communicate properly. Standards are developed in two ways: (1) the
method is so widely used that it comes to dominate; (2) the method is published
by a standard-setting organization. The most important organization in this
respect is the International Telecommunication Union, a specialized agency of
the United Nations, and one of its operational entities, the International
Telegraph and Telephone Consultative Committee (CCITT). Other organizations in
the area of standards are the American National Standards Institute, the
Institute of Electrical Engineers, and the Electronic Industries Association.
One of the goals of these organizations is the full realization of the
integrated services digital network (ISDN), which is projected to be capable of
transmitting through a variety of media and at very high speeds both voice and
nonvoice data around the world in digital form.

Other developments in the industry are aimed at increasing the speed at which
data can be transmitted. Improvements are being made continually in modems and
in the communications networks. Some public data networks support transmission
of 56,000 bits per second (bps), and modems for home use (see Microcomputer) are
capable of as much as 28,800 bps.

Introduction

When a handful of American scientists installed the first node of a new computer
network in the late 60’s, they could not know by any chance what phenomenon they
had launched. They were set a challenging task to develop and realise a
completely new communication system that would be either fully damage-resistant
or at least functional even if an essential part of it was in ruins, in case the
Third World War started. The scientists did what they had been asked to. By 1972
there were thirty-seven nodes already installed and ARPANET (Advanced Research
Projects Agency NET), as the system of the computer nodes was named, was working
(Sterling 1993). Since those “ancient times”, during which the network was used
only for national academic and military purposes (Sterling 1993), much of the
character of the network has changed. Its today users work in both commercial
and non-commercial branches and not just in academic and governmental
institutions. Nor is the network only national: it has expanded to many
countries around the world, the network has become international and in that way
it got its name. People call it Internet.

The popularity of this new phenomenon is rising rapidly, almost beyond belief.
In January 1994 there were an estimated 2 million computers linked to the
Internet. However, this is nothing compared to the number from last year’s
statistics. At the end of 1995, 10 million computers with 40-50 million users
were assumed to be connected to the network-of-networks. If it goes on like this,
most personal computers will be wired to the network at the end of this century
(Internet Society 1996).

The Internet is phenomenal in many ways. One of them is that it connects people
from different nations and cultures. The network enables them to communicate,
exchange opinions and gain information from one another. As each country has its
own national language, in order to communicate and make themselves understood in
this multilingual environment the huge number Internet users need to share a
knowledge of one particular language, a language that would function as a lingua
franca. On the Internet, for various reasons, the lingua franca is English.
Because of the large number of countries into which the Internet has spread and
which bring with them a considerable variety of languages English, for its
status of a global language, has become a necessary communication medium on the
Internet. What is more, the position of English as the language of the network
is strengthened by the explosive growth of the computer web as great numbers of
new users are connecting to it every day.

Internet, in computer science, an open interconnection of networks that enables
connected computers to communicate directly. There is a global, public Internet
and many smaller-scale, controlled-access internets, known as enterprise
internets. In early 1995 more than 50,000 networks and 5 million computers were
connected via the Internet, with a computer growth rate of about 9 percent per
month.

Services

The public Internet supports thousands of operational and experimental services.
Electronic mail (e-mail) allows a message to be sent from one computer to one or
more other computers. Internet e-mail standards have become the means of
interconnecting most of the world’s e-mail systems. E-mail can also be used to
create collaborative groups through the use of special e-mail accounts called
reflectors, or exploders. Users with a common interest join a mailing list, or
alias, and this account automatically distributes mail to all its members. The
World Wide Web allows users to create and use point-and-click hypermedia
presentations. These documents are linked across the Internet to form a vast
repository of information that can be browsed easily. Gopher allows users to
create and use computer file directories. This service is linked across the
Internet to allow other users to browse files. File Transfer Protocol (FTP)
allows users to transfer computer files easily between host computers. This is
still the primary use of the Internet, especially for software distribution, and
many public distribution sites exist. The Usenet service allows users to
distribute news messages automatically among thousands of structured newsgroups.
Telnet allows users to log in to another computer from a remote location. Simple
Network Management Protocol (SNMP) allows almost any Internet object to be
remotely monitored and controlled.

Connection

Internets are constructed using many kinds of electronic transport media,
including optical fiber, telephone lines, satellite systems, and local area
networks. They can connect almost any kind of computer or operating system, and
they are self-aware of their capabilities. An internet is usually implemented
using international standards collectively called Transmission Control
Protocol/Internet Protocol (TCP/IP). The protocols are implemented in software
running on the connected computer. Most computers connected to the internet are
called hosts. Computers that route data, or data packets, to other computers are
called routers. Networks and computers that are part of the global Internet
possess unique registered addresses and obtain access from Internet service
providers. There are four ways to connect to the public Internet: by host,
network, terminal, or gateway access. Host access is usually done either with
local area networks or with the use of telephone lines and modems combined with
Internet software on a personal computer. Host access allows the attached
computer to fully interact with any other attached computerlimited only by the
bandwidth of the connection and the capability of the computer. Network access
is similar to host access, but it is usually done via a leased telephone line
that connects to a local or wide area network. All the attached computers can
become Internet hosts. Terminal access is usually done via telephone lines and
modems combined with terminal-emulation software on a personal computer. It
allows interaction with another computer that is an Internet host. Gateway
access is similar to terminal access but is provided via on-line or similar
proprietary services, or other networks such as Bitnet, Fidonets, or UUCP nets
that allow users minimally to exchange e-mail with the Internet.

Development

The Internet technology was developed principally by American computer scientist
Vinton Cerf in 1973 as part of a United States Department of Defense Advanced
Research Projects Agency (DARPA) project managed by American engineer Robert
Kahn. In 1984 the development of the technology and the running of the network
were turned over to the private sector and to government research and scientific
agencies for further development. Since its inception, the Internet has
continued to grow rapidly. In early 1995, access was available in 180 countries
and there were more than 30 million users. It is expected that 100 million
computers will be connected via the public Internet by 2000, and even more via
enterprise internets. The technology and the Internet have supported global
collaboration among people and organizations, information sharing, network
innovations, and rapid business transactions. The development of the World Wide
Web is fueling the introduction of new business tools and uses that may lead to
billions of dollars worth of business transactions on the Internet in the future.

In the Internet nowadays, the majority of computers are from the commercial
sphere (Vrabec 1996). In fact, the commercialisation of the network, which has
been taking place during the last three or four years, has caused the recent
boom of the network, of the WWW service in particular (Vrabec 1996). It all
started in the network’s homeland in 1986, when ARPANET was gradually replaced
by a newer and technologically better built network called NSFNET. This network
was more open to private and commercial organisations (Vrabec 1996) which,
realising the potential of the possible commercial use of the Internet, started
to connect themselves to the network.

There are several possibilities how commercial organisations can benefit from
their connection to the English-speaking Internet. Internet users are supposed
to be able to speak and understand English, and actually most of them do. With
the rapidly rising number of users, the network is a potential world market
(Vrabec 1996) and English will be its important tool. The status of English as a
world language, or rather its large number of people who are able to process and
use information in English, already enables commercial organisations to present
themselves, their work and their products on the Internet. Thanks to English and
the Internet companies can correspond with their partners abroad, respond to any
question or give advice on any problem that their international customers can
have with their products almost immediately (Vrabec 1996). Considering the fact
that many of the biggest, economically strongest and influential organisations
are from the USA or other native English speaking countries, the
commercialisation has very much reinforced the use of English on the Internet.

BIBLIOGRAPHY:

Cepek, Ales and Vrabec, Vladimir 1995 Internet 🙂 CZ, Praha, Grada Demel, Jiri
1995 Internet pro zacatecniky, Praha, NEKLAN Falk, Bennett 1994 InternetROADMAP,
translated by David Krsensk, Praha, Computer Press Jenkins, Simon 1995 “The
Triumph Of English” The Times, May 1995 Philipson, Robert 1992 Linguistic
imperialism, Oxford, Oxford University Press Schmidt, Jan 1996 “Carka , hacek a
WWW” Computer Echo Vol. 3/6 (also available on http://omicron.felk.cvut.cz/
comecho/ce/journal.html) Sterling, Bruce 1993 “A short history of the Internet”
The magazine Of Fantasy And Science Fiction, Feb. 1993 Vrabec, Vladimir 1996
“Komerce na Internetu” LanCom, Vol. 4/3