Micro #19 28 мая 1999

Интернет

Internet - a brief introduction before the real work on the Internet.

         INTERNET. INTRODUCTORY LECTURE



          Methodological guidelines


  This lecture can be used as a brief introductory course to 
the real work on the Internet and is designed to untrained 
listeners. 


  The concept of computer telecommunications

The term "computer telecommunications"
denotes computer networks, performing remote data transmission
between computers.
Computer networks are divided into local and global. Local area 
networks connect users, remote maximum a few kilometers, more 
often - being in the same building or working in one 
organization. Global networks bring together computers located 
in different cities and countries. In this lecture we consider 
the global computer network. Computer telecommunications allow 
for quick transmit information in any form

(Numerical data, text, graphics, sound,
video, etc.).
With this technology, people got
access to information of interest, regardless of where they
live.


             The concept of Internet

In the world there are thousands of different
computer networks. Previously, these networks were not linked 
and could not communicate. It was very uncomfortable, so the 
experts look for ways to you can link together a variety of

computer networks running on different
hardware and software platforms. This
method of communication has been found. For it was based
taken by the network protocol IP, developed by
About 20 years ago for the needs of union
networks of the Ministry of Defense. This standard is good in 
that it provides the high reliability of the network and allows 
ensuring interoperability of computers manufactured by 
different companies. By the experimental network of the 
Ministry of Defense began to connect more and more new users. 
Currently, community interconnected networks running over IP, 
swept the world and became known as the Internet. Thus, wrong 
to say that the Internet - a network. On Indeed, a combination 
of a large number of networks that support common standards. 
Each of these networks may belong to someone else and managed 
by someone but the Internet as a whole belongs to no one

and has no central authority
management. In addition, many networks, not
using the protocol of IP, now have
gateways to the Internet. Give the definition of the Internet, 
taken from the book "Access to Internet via e-mail (Doctor 
Bob's Guide to Offline Internet Access) ", 4 th edition - March 
1995, translation: Vadim Fedorov, 1995 Internet (noun) - and 
his burgeoning collection of computer networks, beset globe, 
connecting government, educational and commercial institutions,

as well as individual citizens, with a wide range of computer 
services, resources and information. The complex network of 
agreements and common tools are designed with web to create one 
large network in which computers are connected together, 
interact with many different hardware and software platforms. 
Internet Services When you connect to the Internet user has 
access to certain services (Services). Below we list the most

popular ones.


        E-mail (E-mail)

One of the most traditional and common types of service on the 
Internet - it e-mail. The subscriber registers

in the network and receives a unique address. Addresses
the Internet are in the shape of the form user @ domain, where 
"domain" represents a few symbolic fields separated by dots. 
"Domain" - the name of the computer the network, and "user" - 
the username on this computer. If your correspondent has an 
address in this form, you can safely send him a letter from any 
network that is part of the Internet. For example, E-mail the 
author of this lecture looks like this:


                        vas@vas.tomsk.su

Email has many advantages
Compared with the traditional "paper" mail:

    Letters to go much faster.

    Shipping costs are cheaper.

    Can automatically receive an increase in
    adequately informed about the delivery.

    Letters are not lost and are delivered

    clock.

    Address is not tied to a geographical

    point, and to a specific person.



             Teleconferences


  Electronic newsgroups represent
a thematic exchange of electronic
letters between the subscribers. Conference
serves to organize the discussion of one or
other issues. The letter, sent by a subscriber at a conference 
on a particular subject, sent to all subscribers connected to 
the conference (signed at this conference). And each subscriber 
is connected to a conference, may receive all who come in her 
letter. There are thousands of case conferences devoted to 
almost any areas of human interest. To

to connect to the conference and receive information from it, 
as well as to send a letter to the conference and it was sent 
to all subscribers, the subscribers of this conference, it is 
necessary to know the name of the conference. In order to 
navigate this sea of ​​topics and information, the names of 
newsgroups are set according to with certain rules. Existing

rules define the hierarchical names
conferences. These names represent
a few words separated by dots, with each subsequent precise 
affiliation of the conference to the topic for a thematic 
section - the hierarchy. Here are the basic hierarchy 
(So-called "Big Six"): 

comp

  Conference to discuss issues

  related to computers and programming
  vaniem.

news

  Discussion of the program to exchange news,

  questions of development of teleconferencing

rec

  Recreation, hobbies, passions.

sci

  Conference for the discussion and share experiences
  that the various scientific disciplines.

soc

  Questions of public life.

talk

  Conference targeted for discussion
  Denia controversial issues, for fans

  just to talk on any subject.

misc

  Topics that do not fall into one of the other

  classes or related directly to several
  Kim.

Apart from the "Big Six", there are regional hierarchy, a 
number of special hierarchies, and alt - the alternative 
hierarchy, such conferences are not available everywhere or not 
all. May contain information prohibited or unacceptable for any

reasons. For example, on behalf of the Conference
You can easily guess that the debate
conferences
comp.graphics.apps.photoshop
alt.binaries.pictures.erotica.blondes
relcom.commerce.audio-video


                   FTP

FTP (File Transfer Protocol) means
"File Transfer Protocol" and is
means of access to files stored on
remote computer systems. Allows
copy files from a remote computer
to your local computer and vice versa. For
mass user of greatest interest
represent the public FTP-servers. By
tradition to a request under the user name
accessing that server must respond
anonymous (unnamed). Hence it appeared
the name of a popular Internet services:
ANONYMOUS FTP, that is getting files from
public server. Thousands of such servers. For example, firms - 
manufacturers software products have their own servers,

where you can get the files to fix bugs, seen at work
programs to-date information, instructions and
other information. The ftp-server
manufacturers of hardware you can always find the latest 
drivers. There are many specialized servers

collections of files for every taste.


                   IRC

IRC (Internet Relay Chat) - Services, through the
which users can "talk"
with each other through the whole world. IRC allows people 
located even thousands of miles away from each other, engage in 
dialogue or entire conference in real time.



    World-Wide Web (World Wide)

The World Wide Web - is the most popular service on the 
Internet. Through it you can access all other services (Ftp, 
email, etc.). It is built on technology that is based on the 
concept of "hypertext." 


           The concept of hypertext

Hypertext - this information is presented in such a way that 
certain words in text at any time to "reveal" and

obtained in this way about them for more information. That is, 
these words are links to other documents that may be text, 
files, pictures, sound bites, or whatever. Process following 
links can continue to arbitrarily as long. Thus, work on the 
Internet with WWW is more reminiscent of view of an illustrated 
magazine or encyclopedia. To get to your resource, simply click 
the mouse of selected words or graphic elements. Uniform 
Resource Locator (URL) World Wide Web, all information is 
available on the Internet, is presented in the form of 
hypertext pages. Each page has its own unique URL. Any resource 
on the Internet can be found, knowing the URL. To do this, 
simply enter the URL in the box browser (the software to work

with the WWW). URL has the following format:
naimenovanie_protokola: / / servername / path
For example, URL World Service BBC Radio as follows:

      http://www.bbc.co.uk/worldservice/
"The name of the protocol" may be read: ftp, telnet, gopher, 
news, http, mailto. Server Name - a domain name

server that hosts the desired resource. "The Way" - the full 
path name of the file on the server. 


            Search engines

Internet is huge and filled with various information. How to 
find what you need? To do this, there are search engines. 
Knowing the search engine URL, you can contact her and give her 
a task to find the information you need. Most often, 
information retrieval can be carried out in two ways. One of 
them is that you can specify the keyword

or words and search a (ab%, will give you
URL of all known her pages on the Internet, which meets a key
word. Another way is
that all the major search engines
There are collections of URL, grouped by
topics. Here are some URL's most popular search engines:

Infoseek

  http://guide.infoseek.com/

AltaVista Search

  http://altavista.digital.com/

Yahoo!

  http://www.yahoo.com/

WhoWhere? E-mail Addresses

  http://www.whowhere.com/

Deja News - the Source for Internet Newsgroups

  http://www.dejanews.com/

FTP Search

  http://ftpsearch.unit.no/ftpsearch

Typically, each Internet user
has a favorite search engine.
WWW embodies the idea of ​​the most user-friendly graphical 
interface in the Internet. Therefore, it is not surprising that 
it is the WWW service in the last two year, growing faster than 
any other The Internet service. This is facilitated by

and that using WWW interface can be
comfortable to work with other, more
old and traditional Internet resources: email, ftp, etc.


                Conclusion

It takes just a few hours of practical work in the internet to 
learn to look at it the information you need. 


Text taken from the server ZSU. 29.05.1999