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UNIT 8 INTERNET TOOLS

Structure

8.0 Objectives

8.1 Introduction

8.2 Internet Search Tools

8.2.1 Search Engines

8.2.2 Subject Directories

8.2.3 Deep Web or Invisible Web

8.3 Remote Access and File Transfer Tools

8.3.1 Telnet

8.3.2 File Transfer Protocol (FTP)

8.4 Communication Tools

8.4.1 E-Mail

8.4.2 Discussion Groups

8.5 Conferencing Tools

8.6 Other Tools

8.7 Summary

8.8 Keywords

8.9 Answers to Self Check Exercises

8.10 References and Further Reading

8.1 OBJECTIVES

After reading this Unit, you will be able to:

categorise different types of Internet tools;

elaborate search tools viz. search engines, subject directories and deep

web or invisible web;

explain the functionality of telnet and FTP;

discuss different communication tools like e-mail, discussion forums etc.;

describe different types of internet based audio, video and text conferencing

tools; and

enumerate different types of multimedia tools.

8.2 INTRODUCTION

Internet has been around for quite sometime. However, it is only in the recent

years that its popularity has increased to a great extent. The Internet is an

information communications channel that enables broadcast and exchange of

electronic information amongst individuals and institutions. The usage varies

from a simple e-mail to a complex video conferencing facility.

The Internet provides several services viz. searching for information (search

engines, directories), communication (through e-mail, chat, newsgroups,133



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mailing list etc.), file transfer protocol (FTP), telnet or remote login,

conferencing, media broadcasting, etc. World Wide Web is currently the service

that most people use to access Internet services. A variety of tools have been

developed over the years to make effective use of these services. In this unit

you will get familiarised with some of the popular Internet tools.

8.3 INTERNET SEARCH TOOLS

There are millions of servers available all over the world hosting private and

public websites with their web pages offering information and services. The

information available on the Internet can be in the form of HTML pages,

attached files in various formats (Word processor, PDF, video, audio etc.),

databases attached to websites, dynamic page elements viz. animation, online

forms etc. There are so many information items available on the net which

makes it difficult to locate the exact required information. As you all know by

now that there is no central authority in charge of the Internet. Anyone can

create or withdraw websites as and when required. Because of the dynamicnature of the web, it is difficult to keep track of all the information that are

available in the web. If you are aware of availability of specific information

on the net, all it takes is to provide the exact site address (URL) in the browser

to go to that site. But if you have no idea as to where to look for a specific

information, what do you do in such a situation? You then need to take help of

different types of search tools that are available on the net. The search tools

can be categorised into following three types:

Search engines

Subject directories

Deep web or invisible web.

Let us discuss these three categories in details in the following sections.

8.2.1 Search Engines

A search engine is a program that searches through keywords or a search term.

Search engines use automated software to create indexes of web pages. Search

engines comprise the following three basic elements:

Spiders: These are programs (also known as web crawlers, web robots,web wanderers) that navigate the web from link to link identifying and

reading pages and retrieving all documents that are referenced.

Index: It is a database containing a copy of each web page gathered by

the spider. After spiders find pages, they pass them on to another computer

program for indexing. The indexing program identifies the text, links

and other content in the page, and stores them in the search engine database

files.

Search and retrieval mechanism: It is a program that enables users to

put queries to the index and returns results in some schematic order. Thesearch engine database can be searched through keyword or through other

advanced search approaches. The required pages will be retrieved if the

search term matches the content stored in the index of a search engine.



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Search engines can be further categorised into two types: primary and meta

search engines. Primary search engine uses a spider to collect its own searchable

index whereas, meta search engine searches multiple search engines

simultaneously.

There are numerous search engines available. Some of the popular ones are–

Google, Yahoo, Infoseek, Looksmart, Teoma, Lycos, Hotbot, etc. For meta-search engines you can have a look into ixquick (http://www.ixquick.com),

Fazzle (http://www.fazzle.com), ProFusion (http://www.profusion.com), Query

Server (http://www.queryserver.com), MetaCrawler (http://www.metacrawler.com).

Now let us see how to use search engines to retrieve information. For this we

will use the Google search engine. Open the Google main page at http://

www.google.com/ (Fig.8.1).

Fig. 8.1: Google Main Page

In the search box enter the term IGNOU and click search. Google will search

the web for those websites which contain the word “IGNOU” and list those

addresses as shown in Fig. 8.2. In this case it has found 58, 200 matches for

IGNOU. Each record is displayed with a few lines of information picked upfrom the retrieved pages so as to help a user to find its relevance. On clicking

any of these links, the required page will be transferred from the concerned

server and displayed on your screen. Search engines usually give us a list of

best matches to least likely matches in descending order.

Most search engines allow you to enter very specific, even complicated search

queries. Usually a single keyword or a couple of words will be sufficient to

search for the relevant information. For pinpointed searching you can employ

one of the following methods to search for specific information.

i) Phrase searching: one can refine the search by putting two or more wordsforming a phrase within quotations e.g. “library education”.




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Fig. 8.2: Search Result for IGNOU

ii) Boolean Logic: most search engines employ the principles of Boolean

Logic. The terms ‘and’ ‘or’ and ‘not’ can be used to narrow down or

broaden your search e.g. “library education and USA and UK”, here,

‘AND’ is used for narrowing a search. Similarly, ‘OR’ can be used to

broaden it and ‘NOT’ to refine the search.

iii) Field search: Field specific searching is possible by defining the field to

search e.g. Title: global warming, URL: warming.

iv) Plus and Minus signs: place the plus sign(+) in front of all words you

wish to retrieve and minus signs(-) for those which you want to eliminate.

8.2.2 Subject Directories

Subject directories are built by human selection and not by computers or robot

programs as in the case of search engines. It is a service that offers a collection

of links to Internet resources submitted by site creators or evaluators and

organised into subject categories. Directories are useful for topic based

searches. There are two categories of subject directories:

i) Academic and professional directories: These are generally created and

maintained by subject experts or librarians and are usually associated with

librarians and academic institutions. There are thousands of specialised

directories on practically every subject. Librarians Index (http://lii.org),

Infomine (http://infomine.ucr.edu), Academic Info (http://

www.academicinfo.net) and Bubl Link (http://bubl.ac.uk/link) are some

examples of professional directories.

ii) Commercial portals: These are meant to cater to the general public. They

cover wide range of topics and often emphasise on entertainment, travel,sports etc. Yahoo, Google, LookSmart are some examples of such

directories.



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8.2.3 Deep Web or Invisible Web

These are pages that cannot be found by search engines and are rarely available

in subject directories. They comprise information that is stored in databases

as well as multimedia and other files. Search engine spiders cannot index

these databases due to a number of reasons:

i) Spiders cannot go inside database tables and extract the data.

ii) Spiders are incapable of gathering non-textual data such as multimedia

files, graphical files and documents in proprietary formats such as PDF

files.

iii) Sites requiring registration or passwords and login id are excluded by

spiders as they require ‘typing in’ which is not possible for spiders.

Deep web sites or database-driven websites hosts dynamically changing content

such as the latest news, job postings, flight and train related information etc.

The information content is normally stored in a database such as phonebooklisting, list of professionals such as lawyers, doctors etc., dictionary definitions,

geographical information, etc. in a deep web or hidden website.

There are websites that specialise in collecting indexing databases available in

the web. Some of examples of such sites that collect searchable databases on

the web are:

Complete Planet (http://aip.completeplanet.com)

Direct Search (http://www.freepint.com/gary/direct.htm)

Invisible web.net (http://www.invisible-web.net)

ProFusion (http://www.profusion.com/index.htm)

Search.com (http://www.search.com).

Self Check Exercise

1) Discuss briefly the three basic elements of search engines.

Note: i) Write your answer in the space given below.

ii) Check your answer with the answers given at the end of this Unit.

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8.3 REMOTE ACCESS AND FILE TRANSFER TOOLS

Telnet and FTP are two commonly used Internet tools. Telnet enables remote

access to other computers whereas FTP allows uploading/downloading of files

both personal as well as general files.

8.3.1 TelnetTelnet is a program that allows you to log on to the computers on the Internet

and use online databases, library catalogues, chat services, etc. To Telnet to a

computer you must know its address. This may comprise words, for example,

spacelink.msfc.nasa.gov or numbers (IP address: 140.147.254.3). Some services

require logging into a specific port on the remote computer. For this you will

be required to type the port number after the Internet address for example,

downwind.sprl.umich.edu:3000.

Telnet is based on client/server model. The client program running on your

machine initiates the connection with a server program running on a remote

machine. Telnet lets you log on to another computer from your computerusing Internet. For this you will require valid user id and password to access

the remote computer. However, there are many Internet hosts providing public

resources which are accessible through special guest account.

To use telnet you have to run a telnet client program. If you access the Internet

using a shell account, your telnet client will be the Unix telnet program. In

case of a PC, you have to run a windows client. The windows operating system

has its own telnet client. In windows you can start the telnet program by

following these steps:

i) Go to start and click run.

ii) In the ‘Run window type telnet and then the IP address of the computer

you want to access then click OK.

Fig. 8.3: Run Window

To get access to the system you will have to provide the user id and password.

In the following example the IGNOU LibSys server is accessed through telnet.

Fig. 8.4: Accessing IGNOU Libsys Server through Telnet

By entering user id and Password for the Libsys Library System you can enter

Libsys interface and work in the remote computer as if you have been working

on the server itself.



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Fig 8.5: Telnet Access to IGNOU’s Libsys Server

The alternate way is to go to the DOS prompt and enter the telnet command.

Telnet sessions are text based and do not have any graphics. With the growing

popularity of web, telnet is now less frequently used as a means to access toinformation on the Internet.

8.3.2 File Transfer Protocol (FTP)

FTP is an Internet service that allows transfer of file from one computer to

another. A file can be a software program, a game, a text document, a

spreadsheet, a graphic, animation, a sound or a video file.

There are two methods of FTP. In the first method one has to log on to the

remote host machine having a valid account with user id and password. The

second method is known as anonymous FTP, where one has to sign in as a

guest or as an anonymous user. Like telnet, FTP is also based on a client/

server architecture. Many FTP client software programs are available which

make file transfer faster and accurate. You can download a free trial version

of WS-FTP from Ipswitch Home Page. After installation when you start the

programme the following screen will be displayed.

Fig 8.6: Ipswitch WS_FTP Home Page




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To connect to the remote server click connection wizard. The connection

wizard will require entry of site name, server address, user name and password

of the remote server. Click finish to connect to the remote server. Once you

are connected you will see a screen similar to the one given below (Fig.8.7).

Fig 8.7: Ipswitch WS_FTP Home Page after Connection with the Remote Host

The left frame shows the files of your own computer and the right frame lists

the ones available on the remote host. To download a file from remote host,

select it and click the arrow pointing towards the left frame. This will download

the file from the remote host. To upload a file similar process is to be followed

but in the opposite direction.

The latest web browsers now available, have inbuilt FTP capability which

makes downloading of files a very simple operation requiring no additional

FTP software or knowledge of FTP commands.

Self Check Exercise

1) Mention briefly the basic difference between Telnet and FTP.

Note: i) Write your answer in the space given below.ii) Check your answer with the answers given at the end of this Unit.

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8.4 COMMUNICATION TOOLS

8.4.1 E-Mail

Electronic mail or e-mail in short has made a dramatic change in the personal

and business communication all over the world in the last few years. It is one

of the most popular and widely used Internet services. Electronic mail is a

service that can be made available either through local area network or through

Internet.

E-mail allows computer users to exchange messages, locally and worldwide.

The messages may be sent to a single person or to a group of persons at the

same time in a matter of seconds.

The messages may be in the form of text only i.e., ASCII files or it may be

binary files in different formats e.g. Word, PowerPoint, Excel sent as

attachments. Basic e-mail functions include:

Reading mails (collected in inbox)

Composing new messages

Replying to the messages received

Forwarding messages to other e-mail addresses

Saving draft messages

Attachment of file

Deleting and re-filing messages in some other storage area

A typical mail interface looks like this:

Fig. 8.8: Microsoft Outlook Interface




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Fig. 8.9: A Mail Message in Microsoft Outlook

Fig. 8.10: Interface for Sending Mail in Microsoft Outlook

8.3.1 Discussion Groups

Discussion groups exist in two forms: electronic mailing lists commonly known

as listservs and Usenet newsgroups. Listservs are electronic groups focused

on a particular subject. Subscription to a listserv is done by sending an e-mail

message to a computer program called a listserver. Listservers are located on

computer network throughout the world. The program handles subscription

information and distributes messages to and from users. Every e-mail message

sent to the listserv is distributed to all the members of that listserv. To participate

in a listserv discussion group, you must have an e-mail account. Listserv

discussion groups can be a small group with a few participants or it could be



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large one with thousands of members participating in the discussion. There

are vast number of listservs available covering almost any conceivable topic.

It does not cost anything to subscribe to a listserv. To subscribe you generally

have to send an e-mail message: “subscribe (listserv) Firstname Lastname” to

the listserv address. You will be automatically informed through an e-mail

message that you have been registered to the mailing list. Each listserv has an

address where the users can send subscription request, un-subscribe and searchfor the archives. Most listservs maintain their archives, where you can view

subject wise, author wise, date wise or topic wise threaded discussions. A

sample of listserv archive is given below (Fig. 8.11).

Fig. 8.11: Listserv Archive

Newsgroups or Usenet on the other hand are areas where members post

electronic messages for other members to view and respond. They are basically

global electronic bulletin board systems in which millions of computer users

exchange information on a vast range of topics. They are generally used to ask

questions, seek opinion, share facts, distribute files for downloading. There

are thousands of newsgroups available on the net and the number is expanding

at a very fast pace. The major difference between e-mail discussion groups

and Usenet/ Newsgroup is that the Usenet messages are stored in central

computers and the users have to connect to them to read or download messagesposted on them, whereas in e-mail discussion groups messages are posted in

the mailbox of each member. Most of the Newsgroups are for general public

but there are some which are private ones, requiring login id and password.

Some of the Newsgroups may be read only in which one can only read the

messages but cannot post any message. Many of the newsgroups are academic

in nature but there are ones that are organised around recreational topics as

well.

Self Check Exercise

1) What are listservs?

Note: i) Write your answer in the space given below.

ii) Check your answer with the answers given at the end of this Unit.




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8.5 CONFERENCING TOOLS

Internet facilitates real time communication through number of conferencing

tools. Conferencing can be in various forms viz., audio/video conferencing,

web based chats, bulletin board systems, shared white boards, etc. We will

discuss each of these categories in the following paragraphs.

Video conferencing via the net has enormous potential for enhancing

communication in all spheres of life – business, governance, education etc.Video conferencing involves broadcasting and receiving of video signals over

the Internet in real-time. Conferencing can be in one-to-one, one-to-many

(multicast) and many-to-many (multipoint) modes.

For video conferencing the basic-requirements are: a video camera (webcam

is good enough), microphone, speakers or headphones, sound and video cards

with associated software and networking components. Networking can occur

over fast Ethernet, TCP/IP (the Internet), cable network or via ISDN (Integrated

Services Digital Network). Video-conferencing, however, requires high speed

connection for acceptable quality of video output. This is a hindrance to its

wide acceptance as a mode of communication for the general public.In audio conferencing, voice is digitised and sent through the Internet to the

final destination. For this you require a headset with earphones, a microphone

and conferencing software. Internet can also be used to make telephone calls

around the world at a cost of local connection. This can serve as an audio

conferencing tool to make computer to computer and at times computer to

telephone calls.

Fig 8.12: NetMeeting Interface

Source: http://www.microsoft.com/Windows/NetMeeting



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Web based conferencing software such as NetMeeting, CU-SeeMe etc. enables

geographically dispersed group of people to communicate in real time using

video, audio and collaborative screen sharing tools simultaneously. NetMeeting

offers a complete Internet conferencing solution and comes inbuilt with the

Windows Operating System (Windows 2000 and above versions).

Following tools are available in the NetMeeting software:

Video and Audio Conferencing

NetMeeting’s audio and video conferencing features let you communicate

with anyone on the Internet.

Chat

Chat lets you conduct real-time conversations via text, with as many

people as you like.

Internet Directory

The Microsoft Internet Directory is a Website provided and maintained

by Microsoft to locate people to call on the Internet.

File Transfer

File transfer lets you send one or more files in the background during a

NetMeeting conference.

Program Sharing

NetMeeting’s Program Sharing feature allows you to share multiple

programs during a conference with flexibility, and also enables you to

retain greater control over the way they’re used.

Security

NetMeeting uses three types of security measures to protect your privacy.

Remote Desktop Sharing

Remote Desktop Sharing lets you operate a computer from a remotelocation.

Advanced Calling

This feature gives you the flexibility to send a mail message to a

NetMeeting user or initiate a NetMeeting call directly from your mail

address book.

Whiteboard

The whiteboard lets you collaborate in real time with others via graphicinformation.




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Conferencing without audio and video application is also possible on the web

with document management, multimedia conferencing or screen sharing tools.

Document sharing packages enables sharing of word processing or spreadsheet

files and work on them jointly sitting at remote locations. Multimedia

conferencing and screen sharing tools enables users to control as well as

synchronise presentations available in text, graphic, image, audio and video

formats in real time.

Web chats and instant messaging are the other real time communication tools

that are very popular and widely used. Chat windows or rooms allow

participants to share what they type. These are primarily text only systems,

but some systems also have additional facility of incorporating audio and

snapshots. Interactive Relay Chat (IRC) is the original chat feature that is

supported by most of the browsers. Chat rooms require global chat protocol to

conduct online chat sessions. These can generally support fifty to thousand

users in a session.

A variation of the web chat is the instant messaging (IM) in which a user cancommunicate with another user who is currently logged in by typing messages.

While chat rooms are ideal for discussing a topic among a group of participants,

the instant messaging is more suitable for one to one private conversation with

friends and family members. To send and receive instant messages, a user

needs a connection to the Internet and instant messaging software. ICQ is a

popular IM tool available at http://www.icq.com. Yahoo, MSN and AOL’s

Instant Messenger are also quite popular. The instant messaging software

enables a user to set up a list of contacts who also use the same program. Once

this list is set up, one can see each contact as they come online. A chat session

can be started with them quickly and easily. Most conversations are typed textmessages that are sent back and forth, though more advanced users can exchange

voice, video, files and more.

8.6 OTHER TOOLS

Virtual Environment

Internet supports a wide range of synchronous activity through virtual

environments. These are basically imaginary settings in which one can interact

with others. The first such type of virtual environment developed was the Multi-

User Dungeon (MUD). A MUD is an elaborate computer mediated imaginary environment which often involves individuals assuming a character and getting

involved in virtual role play. A significant feature of most of the MUDS software

is that users can create things that stay on after they leave and others can interact

in their absence. This allows the world to be built gradually and collectively.

There are a large number of MUDs available on the net. Other variations of

the MUDs are:

MOO (MUD Object Oriented)

MUSE (Multi-user Simulated Environment)

MUSH (Multi-User Shared Hallucination)

MUCK (Multi-User Chat Kingdom)



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Streaming Media

The use of streaming media to deliver audio and video over the web is growing

popular and is very useful in online learning environment. Streaming audio or

video refers to the process in which the user receives files in small information

packets and plays the media piece by piece. The process is almost invisible

except for the initial buffering that takes place. The advantage of streaming isthat the user need not wait for the entire file to be downloaded before playing.

Streaming media can be delivered live or it can be archived for later use.

Streaming media requires special software/ plug-in to be installed in your

system. Application players required for this purpose are: Real player (http://

www.real.com), Windows Media Player (http://www.microsoft.com/windows/

windowsmedia), and QuickTime (http://www.apple.com/quicktime/download).

The quality level of the streaming audio and video are determined by the internet

connection bandwidth, computer’s processor speed and the RAM of the system.

Internet congestion may also hamper the smooth delivery of media files.

Fig. 8.13: Real Player Interface

8.7 SUMMARY

This unit explored various tools used on the Internet for information,communication, and interaction. You also learnt about various Internet utilities,

tools, and applications. The World Wide Web (WWW or The Web), is an

increasingly pervasive medium that has made it possible for people world

wide to access and publish globally accessible information. It has provided a

platform to share information. Telnet provides means for accessing information

on another computer from your own computer. Once you are connected to the

Internet, you can start a Telnet session. If you don’t have a Telnet program,

you can obtain one from any of the ftp site archives. FTP is one of the most

common methods used to transfer files from one computer to another. You

also learned about Internet search tools called search engines. Search engines

are websites which help the user to find websites which match theirrequirements. They work by keeping a database of web-pages, along with

keywords to describe their content. The keywords are derived from each web-




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page. By using these keywords or phrases, you can search text in millions of

Web pages. We also explored the basic setup of email and the newsgroups.

Listservs contain discussions of various subjects and are a good tool for keeping

up-to-date on current trends in a certain field. We also discussed about audio/

video conferencing, web-based chats and various web-conferencing softwares

which enable geographically dispersed groups of people to communicate with

each other.

8.8 KEYWORDS

ASCII : American Standard Code for Information

Interchange. The basis of character sets

used in almost all present-day computers.

Binary Files : Data files in which the information is

stored in the binary code of 1’s and 0’s

that make up the basic language of

computing.

Browser : An application program that is used to

connect to sites on the World Wide Web.

Client : A program, such as a Web browser, that

connects to a centralised server program

and obtains information from it.

Client/server Model : A method of sharing computer and

network resources in such a way that

various cl ient programs connect to acentral server to obtain information or to

communicate.

Database : An organised collection of information in

computerised format.

Ethernet : A common method of networking

computers in a LAN (Local Area

Network).

File Transfer Protocol (FTP) : A protocol that defines how to transfer files

from one computer to another.

Internet : A worldwide network of computer

networks. It is an interconnection of large

and small networks around the globe.

ISDN : ISDN (Integrated Services Digital

Network) is a telecommunications

standard that uses digital transmission

technology to support voice, video and

data communications applications over

regular telephone lines.

LAN (Local Area Network) : A network connecting computers in a



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relatively small area such as the same floor

or building, or a group of buildings like a

campus.

Link : A specially designated world or image

that, when selected, takes a Web browser

to a new page or other destination (anembedded Web address).

Multimedia : Incorporating many different media, often

including text, pictures, sounds, video,

animations, and so on.

Port : A logical channel in a communications

system. Each server program, for example,

has a unique port number associated with

it.

Protocol : A set of standards used by computers tocommunicate and exchange information

with one other.

Server : A piece of software or machine that acts

as a centralised source of information or

computing resources (such as Websites,

Gopher menus, FTP archives, and so on),

available to clients.

Site : A location on the Internet, often the host

of one or more servers, or a set of related Web pages.

URL : Stands for Universal Resource Locator and

means an Internet address expressed in a

form that any Web browser can

understand.

8.9 ANSWERS TO SELF CHECK EXERCISES

1) Basic elements of search engines are:

Spiders – These are programs that navigate the web from link to link

identifying and reading pages and retrieving all documents that are

referenced.

Index – It is a database containing a copy of each web page gathered by

the spider. The text, links and other contents in the page are identified and

stored in the search engine database files.

Search and retrieval mechanism – It is a program that enables users to put

queries to the index and retrieve the required information. The search

engine database can be searched through keyword or through other

advanced search approaches.

2) Telnet is a program that allows remote access to other computers on the

Internet and use databases, library catalogues, chat services, etc., whereas




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FTP is an Internet service that allows the transfer of files from one computer

to another.

3) Listservs are electronic groups focused on a particular subject. Listserv

discussion groups can be a small group having few participants or a large

one. Subscription to a listserv is done by sending an e-mail message to a

computer program called Listservs. This program handles subscriptioninformation and distributes messages to and from users.

8.10 REFERENCES AND FURTHER READING

Kressin, Mark (1997). The Internet and the World Wide Web: A Time Saving

Guide for New Users. New Jersey: Printice Hall.

Crumlish, Christian (1996). Internet for Busy People. New Delhi: Tata

McGraw-Hill.

Carton, Sean and Branwyn, Gareth (1996). Internet Power Toolkit: Cutting – Edge Tools and Techniques for Power Users. Research Triangle Park, NC:

Ventana.

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