ERIC Identifier: ED392466
Publication Date: 1996-02-00
Author: Tennant, Roy
Source: ERIC Clearinghouse on
Information and Technology Syracuse NY.
Internet Basics: Update 1996. ERIC Digest.
This digest briefly describes the Internet computer network, the physical
connections and logical agreements that make it possible, and the applications
and information resources the network provides.
The Internet is a world wide network of
computer networks. It is comprised of thousands of separately administered
networks of many sizes and types. Each of these networks is comprised of as many
as tens of thousands of computers; the total number of individual users of the
Internet is in the millions. This breadth of connectivity fosters an
unparalleled opportunity for communication, collaboration, resource sharing, and
PHYSICAL CONNECTIONS AND LOGICAL AGREEMENTS
Internet to exist, there must be connections between computers and agreements on
how they are to communicate. Connections can consist of a variety of
communication media or methods: metal wires, microwave links, packet radio or
fiber optic cables. These connections are usually established within areas or
regions by the particular networking organization with authority or economic
interest in that area. For example, a university academic department may use
Ethernet cable to connect its personal computers and workstations into a local
area network (LAN), which is then connected to the cables the campus uses to
connect its buildings together. These cables are then linked to cables in a
regional network, which itself ties into a national backbone which may be
subsidized by the government. Therefore the path between any two points on the
Internet often traverses physical connections that are administered by a variety
of independent authorities.
For disparate computers (from personal computers to mainframes) to
communicate over a network, there must be agreements on how that should occur.
These agreements are called communication protocols. On the Internet, the
Transmission Control Protocol/Internet Protocol (TCP/IP) suite of protocols
defines communication at a machine-to-machine level. Application software for
accomplishing specific tasks such as those outlined below is written to adhere
to these standards and take advantage of the connectivity that they provide.
Electronic mail, or e-mail, is a fast,
easy, and inexpensive way to communicate with other Internet users around the
world. In addition, it is possible for Internet users to exchange e-mail with
users of other networks such as America Online, Compuserve, Prodigy, and others.
Internet users often find that the expanded capability to communicate with
colleagues around the world leads to important new sources of information,
collaboration, and professional development.
Besides basic correspondence between two network users, e-mail presents
additional opportunities for communication. Through various methods of
distributing e-mail messages to lists of "subscribers," e-mail supports
electronic discussions on a wide range of topics. These discussions bring
together like-minded individuals who use such forums for discussing common
problems, sharing solutions, and examining issues.
THE WORLD WIDE WEB
Presently one of the most widespread
applications on the Internet besides electronic mail is the World Wide Web. By
using a Web application program (often called a "browser" or "client"), Internet
users can find information on a variety of topics hosted by a number of
different kinds of Internet "servers" (computers that offer information to
clients) around the world. Information on the Web is presented to the user as
linked "documents" comprised of text, images, and links to other computer files.
Online subject directories and searchable databases of Web resources provide
basic methods for locating information. The future of the Web will likely
include more sophisticated ways of interacting with online information,
including virtual reality (depictions of three dimensional space), video
conferencing, and other kinds of online interactivity and collaboration.
Telnet allows an Internet user in one location to
establish an online connection with a computer located elsewhere. Once a
connection is established with a remote computer, users can use that remote
system as if their computers were hard-wired terminals of that system. Utilizing
Telnet, an Internet user can establish connections with a multitude of
bibliographic databases (primarily library catalogs, full-text databases, data
files (e.g., statistics, oceanographic data, meteorologic data, geographic data,
etc.), and other online services. Many of these systems are available for any
Internet user to access and use without an account.
FILE TRANSFER PROTOCOL (FTP)
Another application of the
Internet is the ability to transfer files from one Internet-connected computer
to another. This function is provided by the File Transfer Protocol (FTP) of the
TCP/IP protocol suite. In a method similar to using Telnet, network users
initiate an online connection with another Internet computer via FTP. But unlike
Telnet, this online connection can perform only functions related to locating
and transferring files. This includes the ability to change directories, list
files, retrieve files, etc. Also, any World Wide Web client can download (get)
files using FTP, but they generally cannot upload (put).
Types of files that can be transferred using FTP include virtually every kind
of file that can be stored on a computer: text files, software programs, graphic
images, sounds, files formatted for particular software programs (e.g., files
with word processing formatting instructions), and others. Many computer
administrators have set aside portions of their machines to offer files for
anyone on the Internet to retrieve. These archive sites support "anonymous"
logins that do not require an account to access, and therefore are called
anonymous FTP sites.
A PREMIER COMMUNICATIONS UTILITY
What makes the Internet
truly remarkable is that ease and speed of access to information are not
dependent upon proximity. An Internet user can connect to a system on the other
side of the globe as easily as (and generally not much slower than) he or she
can connect to a system in the next building. In addition, since many Internet
users are not at present charged for their network use by their institutions, or
at least are not charged by the level of their use, cost is often not a
significant inhibitor of usage. Therefore the barriers of distance, time and
cost, which are often significant when using other forms of electronic
communication, are often less significant on the Internet.
There are numerous ways to gain access to
the Internet. Access options range from the low-end requirements of a computer,
modem, and an account from an Internet access provider (the typical home
configuration), to the high-end, which requires a computer equipped with a
network card and access to an Ethernet network that is connected to the Internet
(the typical business or organization configuration). Due to the relatively low
cost for Internet access (often cheaper than cable TV), as well as the
availability of inexpensive modems and free or inexpensive Internet software,
virtually any computer user can afford to get access to the Internet and all
that it provides. Those who have more money to spend on Internet access will
soon see an array of fast connection options marketed to home users.
The Internet constantly evolves
through both formal standards development as well as individual and corporate
software creation and enhancement. What began as a U.S. government-subsidized
network to allow scholars and researchers to share supercomputer resources, has
since become a mainstream production network tying together commercial
companies, individuals, and organizations of all kinds. Commercial use of the
Internet has spurred rapid development of new software, and it is a trend that
is likely to continue. Some of the developments that are likely to help
transform the Internet into a ubiquitous and full-featured information appliance
include virtual reality, full-motion, realtime, high quality audio and video,
and advanced scripting and programming capabilities.
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