Internet and Its Applications-UNIT I-II-III (thiruvallur university)

CS & BCA INTERNET AND ITS APPLICATIONS

Student Notes for Computer Science And Computer Applications

Prof. Charles E. Raj

Internet And Its Applications - Student Notes

INTERNET AND ITS APPLICATIONS UNIT- I Connecting to the Internet – Domain Name System - Exchanging E-mail – Sending and Receiving Files Fighting Spam, Sorting Mail and avoiding e-mail viruses – types of viruses – Harmful effects of virus Chatting and Conferencing on the Internet – Online Chatting CONNECTING TO THE INTERNET: Internet Communications Protocols TCP/IP TCP and IP were developed by a department of defense (DOD) research project to connect a number different networks designed by different vendors into a networks of networks. It was initially successful because it delivered a few basic services that everyone needs file transfer, electronic mail, remote logon across a very large number of client and server systems. Several computers in a small department can use TCP/IP on a single LAN. IP: IP is responsible for moving packet of data from node to node. IP forwards each packet based on a four byte destinations address. The internet authorities assign ranges of numbers to different organizations. The organizations assign groups of their numbers to departments. IP operates on gate way machines that move data from department to organizations to region and then around the world. TCP: TCP is responsible for verifying the correct delivery of data from client to server. Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received. INTERNET HOST: Each computer on the internet is called a host computer. The computers on the internet are millions of internet hosts, are connected by cables, phone lines and satellite connections. Internet protocol (IP) address IP defines a universal addressing scheme called IP address. An IP address is a 32 bit binary addressing scheme and each standard address is unique on the internet. IP addressing scheme is used to identify networks, networks devices and network Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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connected machines. The purpose of IP address is to identify each connection to internet and to collect a group of connections to simply routing. Every IP address belongs to distinct class. The class that the IP address belongs to initially determines the network ID and host ID portion of address. There are five different classes of address designated to meet the needs of different organizations. The various classes are given as A, B, C, D and E .the class is presented table in below Class

First octet

Net-ID

Default

subnet

mask A

0-127

First octet

255.0.0.0

B

128-191

First 2 octet

255.255.0.0

C

192.223

First 3 octet

255.255.255.0

D

224-239

-

-

E

240-255

-

-

Finding the IP address: To find out your IP address on a windows XP. 1. On the start menu click control panel. 2. In the control panel window, click on network and internet connections. 3. Click on the network connections icon. 4. Double-click the local area connection and select support tab.

The following dialog box will appear on the screen.

Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Another way to find an IP address 1. Open the command prompt. The command prompt is usually located within the Accessories folder. 2. At the “command prompt” screen type ipconfig then press Enter if this doesn’t work type in ipconfig /all.

Domain and host names: A domain is unique name associated with specific IP address by a program that runs on an internet host computer. Each part of domain is called the sub domain. The sub domains are separated by periods. The name constructed so that each sub domain tells something about the computer. The rightmost sub domain is called the top level domain. Types of Domains: Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Top-level domain The way to understand an address is to read from right to left. In general there are two types of top level domains. I.

Generic domains/organization domains

II.

Country Domains/Geographical domains

1. Generic domains/Organization domains Organizations domains are based on an addressing scheme developed before the days of international networks .edu

Servers that provide educational services

.gov

About the government of a country

.mil

Servers that provide military information

.org

Provide information about the organizations in the world

.com

Servers providing commercial services on the internet

.net

Information services / networks

.int

Organizations established by international treaty

ii. Country Domains/Geographical domains The international top level domain uses a 2-letter country code. Country code toplevel domains are two letter destinations assigned to individual countries. Each country linked to the web has a two letter top level domain. The following table shows the various country code top level domains Domain Country

Domain

country

Domain

country

.in

India

.co

Colombia

.mx

Mexico

.aq

Antarctica

.dk

Denmark

.nz

New Zealand

.at

Australia

.eg

Egypt

.om

Oman

.bd

Bangladesh .af

Afghanistan .pk

Pakistan

.bm

Bermuda

.jp

Japan

.qa

Qatar

.br

brazil

.it

Italy

.sa

Saudi Arabia

.ca

Canada

.is

island

.th

Thailand

.cn

china

.kw

Kuwait

.us

United states

.cu

Cuba

.lk

Srilanka

.uk

United kingdom


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Example: www.google.com www.annauniv.edu.in www.thiruvalluvaruniversity.ac.in SERVERS AND CLIENTS Server: Computer connected to a network that other computers may or may not access. Unlike other computers on a network, a server is a dedicated computer set up for one or more purposes. Example: A user may setup a server to authenticate and allow or prohibit users from accessing a network, send/receive e-mail, manage print jobs, or host a website. Clients: A client is a computer that retrieves information from or uses resources provided by a server or main computer. Many corporate networks are comprised of a client computer at each of the employee’s desks. Each of these computers connects to a central server or mainframe, which allows a lot of the processing to be done on the client side instead of the server side and reduces the processing requirements of the server. Types of servers and clients 

Mail servers



Web servers



FTP servers



New servers



IRC servers

Mail servers: Mail servers are used to receive email from local users and send the email to other users over the internet. Mail servers use the SMTP (simple mail transfer protocol) or ESMTP (extended SMTP). Web servers: A web server accepts HTTP (hypertext transfer protocol) requests from a client and returns the appropriate HTML document. The web server maps the URL provided by the client to the specific document or program located on the server FTP servers: FTP servers are used to transfer files from one computer to another over the internet. FTP servers allow for user authentication. File transfer policies and


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activity logging. FTP servers are accessed by a FTP client who allows the user to move the files between the server computer and the client computer. NEWS servers: They work as source of distributions and delivery for hundreds of available public news groups accessible over the USENET news network. USENET is global bulletin board system that can be approach via internet or via a variety of online services IRC servers: Internet relay chat is comprised of various independent networks of servers that allow users to connect to each other via an IRC network. It is an option for those who seeking real time competence. PORT AND PORT NUMBERS: A port is an additional 16 bit number that uniquely identifies the particular service on any given machine on the internet. Port numbers are 16 bit wide, therefore each computer on the internet has a maximum number of 216 or 65,536 ports. The particular application is identified by its unique port number in the same way that a specific television station has a unique channel number. Port numbers are divided into three ranges: 

Well-known ports are those from 0 through 1,023.



Registered ports are those from 1,024 through 49,151.



Dynamic and private ports are those from 49,152 through 65,535.

These ports are controlled and assigned by the internet assigned number authority (IANA). The following table shows the protocol port numbers: Port

Protocol

Number 21

File Transfer Protocol (FTP)

25

Simple Mail Transfer Protocol (SMTP)

80

Hyper Text Transfer Protocol (HTTP)

110

Post Office Protocol 3 (POP 3)


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DOMAIN NAME SYSTEM: The domain address is converted into number internally. The part of the internet that keeps track of address is called the DNS domain name system DNS server is a computer that translates the domain name of another in to an IP address and vice versa on request. Every computer in the network has an IP address, which specifies its physical network connection. To locate the information in internet two kinds of address can be used. These are domain names and IP addresses. Domain names follow a format called Domain name system. EXCHANGING E-MAIL: Email concepts: Email allows the user to send data in the form of text, pictures, sound and video to a remote computer on the internet. These email services are created by companies on specific web services and can be accessed by anyone anywhere in the world at anytime. Some of the familiar servers that offer free email services on the internet are Yahoo, Rediff, Gmail and Hotmail and etc. These three things that you must have to send and receive email 

An internet email account



A connection to the internet



A software application that handles email

Receiving incoming messages: The incoming messages are received in an email mailbox that resides on a mail server. Depending upon the type of connection that you have, download e-mail from the mail server to your computer or you may read your e-mail from the mail server. Mail server receives and stores email messages in mail boxes by using a protocol called post office protocol 3(POP 3) or internet message access protocol (IMAP) Sending outgoing messages: Write email messages on your computer by using e-mail applications. Then, transfer the messages to an SMTP (simple mail transfer protocol) server, a mail server that accepts outgoing e-mail. The SMTP server that takes care of sending your e-mail messages may be a different server.


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Ways of Accessing E-mail: 

We may use a mail client. Example outlook express, Netscape messenger etc.



We may use a web-based e-mail service.



We may use an online service, such as America online, which has its own mail program.

Email address: Email address consist of three parts 1. The persons login name 2. @ sign 3. Domain name Message headers: Every e-mail message send starts with headers. Each header consists of the type of header example: Sender = [email protected] Wants to send an email to the receive [email protected] Downloading E-mail: When you use a dial-up connection and e-mail software that downloads your message 

You can work either offline or online.



You can choose leave download messages or delete them from the server.

Working offline: The definition of working offline is to work while a computer is not connected to other devices or to the internet. This can be done by disconnecting from your ISP or pulling out the Ethernet cable from the computer. Applications and programs such as web browsers and e-mail programs, have an option to ‘work offline’. Working offline means read your email by the following steps: 

Connect to the internet



Download your email



Disconnect from the internet Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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

Read your email.

Deleting messages from the server Your email program usually deletes them from the POP server after downloading. Our applications have a setting that enables you to choose whether to delete the email from the server. Using abbreviations, emoticons, and smiley’s: Emoticons and smiley's Smiley's are punctuations used to conveying mood or emotions in written online communications. Emoticons are used to compensate for the inability to convey voice inflections, facial expressions, and bodily gestures in written communications. Some emoticons are better known as “smiley”. Emotions can be very effective towards avoiding misinterpretation of the writer intents. The most emoticons will look like a face, eyes, nose and mouth. :)

Happy

:((

Crying

:(

Sad

:))

Laughing

;)

wink

:-&

Sick

:-/

Confused

[-(

Not talking

:P

Tongue

(:|

Tired

:O

Shock

@ }:-

Rose

X-(

Angry

%%

Good luck

B-)

Cool

**==

flag

Abbreviations used in E-mail: Chat abbreviations are commonly used in e-mail, online chatting online discussion forum postings, instant messaging, and in text messaging, especially between cell phone users. Abbreviations Meaning

Abbreviations Meaning

AND

Any day now

CYO

AFK

Away

from DIKU

See you online Do I know you?

keyboard B4N

Bye for now

F2F

Face to face


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BBN

Bye bye now

FAQ

Frequently

ask

questions BBS

Be back soon

GL

Good luck

CU

See you

HAGN

Have a good night

CUL

See you later

HAND

Have a nice day

CYA

See ya

WU?

What’s up?

FORMATTED E-MAIL: HTML: this is formatted with HTML tags just like web pages. It includes text formatting, numbering, bullets, alignments, horizontal lines, backgrounds, hyperlinks. It is actually sent using the MIME protocol. Rich Text Format: this format can be read by most word processing applications. Documents in this format are also called RTF files. MIME (multipurpose internet mail extensions): it is used for attachments. Formatting includes text formatting, pictures, video and sound. Web based E-mail Advantages: 

Using web based email we can access the web as well as read our mail.



Most web-based e-mail is free.

Disadvantages: 

We can read two kinds of messages on the web.

SENDING AND RECEIVING FILES: Attachments: 

An attachment is a file that has been encoded as text so that it can be included in an e-mail message.



The three common ways to encode e-mail attachments are:  MIME- Multipurpose Internet Mail Extension is the standard method.  Unencoding- this method is supported by some older e-mail applications. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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 BinHex- used by some Mac e-mail programs. Sending attachments: 

To send a file by e-mail, create a message to which the file is to be attached.



Address the mail as usual and type the subject. If needed type the next in the body of the message.



Now attach the file by choosing a menu command or by clicking a toolbar button.



Large files can be compressed, so that the sending and downloading time can be minimized.

Receiving attachments: 

Most e-mail applications store the attachments in the mail message.



First, open the message and then open or save the attachment.



When the message with an attachment is deleted, the attachment is also deleted.



To use the attachment later, it has to be saved.

Yahoo mail: Yahoo mail is a free email service offered by the American company yahoo it was launched in 1997. Yahoo mail was the third largest web based email service. It is also the largest web portal providing links to thousands of other websites. These links includes sites from the yahoo directory as well as news stories that are updated several times a day. Sending an attachment file: An attachment is a file that you can include as part of your email message. You can attach all types of files to your message, including word processor or spreadsheet documents, audio files, photos, image files (.bmp, .jpg, etc.), web pages saved as HTML files, and more. You can attach up to 50 files with a maximum message size of 25 MB. To attach a file to a message: 1. Click Compose E-Mail button. 2. Click Attach Files button. 3. Click Browse button to the right of File 1: to navigate to the file you want to attach. 4. Click Attach Files button. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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5. Click done when you are finished. Receiving an attach files When you receive a message with an attachment, you may notice a paper clip in the message. To view the attachment, first open the message. Before you save the file, use the scan with antivirus software to check the file for viruses. FIGHTING SPAM: Controlling E-mail volume and reducing spam: 

The term “spam” is the internet slang that refers to unsolicited commercial email (UCE) or unsolicited bulk email (UBE).



Some people refer to this kind of communication as junk email to equate it with the paper junk mail that comes through the US mail.



Unsolicited email most often contains advertisements for services or products, but very few reputable marketers use UCE to advertise.

The most commonly seen spam includes the following: 

Foreign bank scams or advance fee fraud schemes



Phishing scams, a very popular and dangerous form of email fraud



Pyramid scams, including multilevel marketing (MLM)



Other “get rich quick” or “make money fast” (MMF) schemes.



Quack health products and remedies



Ads for pornographic websites



Offers of software for collecting email address and sending UCE



Offers of bulk emailing services for sending UCE.

How is spam mail generated? Spam is email created by randomly combining characters to form actual e-mail address. Additionally replying to spam causes your e-mail address to be added to the senders address list, generating more spam. What can you do about spam? There are few things you can do about spam: 1. You can set up e-mail “rules” or “filters” that automatically delete unwanted messages. Using filters requires that you know something about the unwanted messages Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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2. It is wise to ignore (delete) spam. Some spammers will automatically add you to an email list and then tell you to “unsubscribe if you do not want to receive further messages”. 3. You can try contacting the ISP (internet service provider) of the person or group that sent the messages and ask for help. Stopping spammers: 

Spam emails are emails sent to you without consent. It is email that you don’t want and didn’t ask for, and its content can cause embarrassment and distress.



If you complain to the sender’s system administrator or postmaster, he or she may close the spammers account.



If you want to get more information, the following websites are to be followed www.stopspam.com www.cauce.org www.spamcon.org www.caude.org

Reporting spam: 

Before you delete your spam, forward your spamto:[email protected] as this is the spam box for FTC (federal trade commission)

Avoiding sending spam If you run an internet mailing list, or any other type of email advertising and promotion, this is what you need to know in order to avoid being accessed of sending spam.  Do not purchase email lists or so-called opt-in lists  Do not send unsolicited emails with an “opt-out” option  Do not request a receipt of delivery for your mailing  Do not use any spamming or harvesting software.  Do not send numerous identical messages. Avoid receiving spam email:  Spam has increasingly become a problem on the internet. While every internet user receives some spam email, certain behaviors on the internet will cause you to receive even more than average  They found that email addresses posted to web sites or in newsgroups attract the most spam. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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SORTING MAIL AND AVOIDING E-MAIL VIRUSES: Preferences you may want to change



Mail & Newsgroups o

Identity (as illustrated above) 

Signature File:



Attach my personal card to messages (as a vCard)

For more information on setting up your signature, go to the Signatures page


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

If you select the Open it option the appropriate application will start and open the file. Selecting Save it to disk will open the Save As dialog box enabling you to save the file to disk.



Try to always use the Save it to disk option, as this decreases the risk of a virus entering your computer.

Click on the OK button Here are 13 useful tips to save your computer from email bugs and viruses. These steps are especially useful for those who use Microsoft Outlook or any other software like Thunder Bird as an email client.

1. Most of the worms which use e-mail to propagate use Microsoft Outlook or Outlook Express to spread. If you need to use Outlook, download and install the latest Outlook security patch from Microsoft. In general, keep your operating system and applications up-to-date and apply the latest patches when they become available. Be sure to get the updates directly from the vendor. 2. When possible, avoid e-mail attachments both when sending and receiving e-mail. 3. Configure Windows to always show file extensions. In Windows 2000, this is done through Explorer via the Tools menu: Tools/Folder Options/View – and uncheck “Hide file extensions for known file types”. This makes it more difficult to for a harmful file (such as an EXE or VBS) to masquerade as a harmless file (such as TXT or JPG).


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4. Never open e-mail attachments with the file extensions VBS, SHS or PIF. These extensions are almost never used in normal attachments but they are frequently used by viruses and worms. 5. Never open attachments with double file extensions such as NAME.BMP.EXE or NAME.TXT.VBS

6. Do not share your folders with other users unless necessary. If you do, make sure you do not share your full drive or your Windows directory. 7. Disconnect your network or modem cable when you’re not using your computer – or just power it down. 8. If you feel that an e-mail you get from a friend is somehow strange – if it is in a foreign language or if it just says odd things, double-check with the friend before opening any attachments. 9. When you receive e-mail advertisements or other unsolicited e-mail, do not open attachments in them or follow web links quoted in them.


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10. Avoid attachments with sexual filenames. E-mail worms often use attachments with names like PORNO.EXE or PAMELA_NUDE. 11.

Do

not

trust

the

icons

of

attachment

file.

Worms

often

send

executable files which have an icon resembling icons of picture, text or archive files – to fool the user. 12. Never accept attachments from strangers in online chat systems such as IRC, ICQ or AOL Instant Messenger. 13. Avoid downloading files from public newsgroups. These are often used by virus writers to distribute their new viruses. TYPES OF VIRUSES Computer Viruses are classified according to their nature of infection and behavior. Different types of computer virus classification are given below. • Boot Sector Virus: A Boot Sector Virus infects the first sector of the hard drive, where the Master Boot Record (MBR) is stored. The Master Boot Record (MBR) stores the disk's primary partition table and to store bootstrapping instructions which are executed after the computer's BIOS passes execution to machine code. If a computer is infected with Boot Sector Virus, when the computer is turned on, the virus launches immediately and is loaded into memory, enabling it to control the computer.


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• File Deleting Viruses: A File Deleting Virus is designed to delete critical files which are the part of Operating System or data files. • Mass Mailer Viruses: Mass Mailer Viruses search e-mail programs like MS outlook for e-mail addresses which are stored in the address book and replicate by e-mailing themselves to the addresses stored in the address book of the e-mail program. • Macro viruses: Macro viruses are written by using the Macro programming languages like VBA, which is a feature of MS office package. A macro is a way to automate and simplify a task that you perform repeatedly in MS office suit (MS Excel, MS word etc). These macros are usually stored as part of the document or spreadsheet and can travel to other systems when these files are transferred to another computers. • Polymorphic Viruses: Polymorphic Viruses have the capability to change their appearance and change their code every time they infect a different system. This helps the Polymorphic Viruses to hide from anti-virus software. • Armored Viruses: Armored Viruses are type of viruses that are designed and written to make itself difficult to detect or analyze. An Armored Virus may also have the ability to protect itself from antivirus programs, making it more difficult to disinfect. • Stealth viruses: Stealth viruses have the capability to hide from operating system or anti-virus software by making changes to file sizes or directory structure. Stealth viruses are anti-heuristic nature which helps them to hide from heuristic detection. • Polymorphic Viruses: Polymorphic viruses change their form in order to avoid detection and disinfection by anti-virus applications. After the work, these types of viruses try to hide from the anti-virus application by encrypting parts of the virus itself. This is known as mutation. • Retrovirus: Retrovirus is another type virus which tries to attack and disable the anti-virus application running on the computer. A retrovirus can be considered antiantivirus. Some Retroviruses attack the anti-virus application and stop it from running or some other destroys the virus definition database. Multiple Characteristic viruses: Multiple Characteristic viruses have different characteristics of viruses and have different capabilities Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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HARMFUL EFFECTS OF VIRUS 

Computer virus can slow down your computer.



Might corrupt your system files.



Might make some programs faulty or corrupt



Might damage your boot sector creating problems when you boot into the windows.



Might steal important information from your computer and send to some other person.



Might change the power ratings of your computer and could blast the system

CHATTING AND CONFERENCING ON THE INTERNET: Online chatting, messaging, and conferencing concepts 

Online chatting or online conferencing enables internet users to exchange text or to have discussions with groups of people in real time.



The groups of people involved may be anywhere in the world.



This group communication can take the form of text, voice, or video, and messages and responses can be changed.

FORMS OF CHAT, MESSAGING AND CONFERENCING Real time chat: Each participant sees each message with seconds of when it is sent, and the reply is given quickly. However, all participants need to be online at a same time.


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Asynchronous chat: Messages are stored so that participate can read them when they have a chance, which allow participants to consider their responses, gather information, and formulate a response carefully. TYPES OF ONLINE CHAT AND CONFERENCING E-mail mailing lists- E-mail messages are sent to one or more people who are selected by the sender. An e-mail mailing list allows messages to be distributed to a list of preselected people called subscribes. Usenet newsgroup- UseNet is a system that allows messages to be distributed throughout the internet. Due to the volume of messages, the messages are divided into newsgroup, or topics Internet relay chat (IRC) - it allows thousands of internet users to participate in real-time text-based chat. Web based chat: many people are program and commands required by IRC. Hence, many websites now provide a web-based way to participate in real-time text-based chat. AOL and CompuServe chat rooms- AOL services allow real-time chat on a wide variety of subjects. Instant messaging: instant messaging (IM) is a form of online communication that allows real-time interaction through computers or mobile devices. Online conferencing: an online conference uses the internet as a conference venue. This means that participants can access the conference from anywhere in the world and can do this at any time, using standard browser software. Advantages of online conferencing:  Traditional conferences mean participants have to travel and stay in a particular place.  Online conference uses internet conference in anywhere in the world.  They are given a password to access the conference and seminar groups as well as closed discussion groups anyone access the internet can participate.  Cheaper because there is no travel, and no accommodation is required.  More convenient you can access it any time you want from anywhere with an internet connections. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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 High-level participation typically, more people will actively participate in an online conference than in a face to face conference. How does chat work? The user’s web browser is used as the client software java application is often downloaded into the web browser to enable this function. We will only be able to chat with users who are connecting to the same server. There are chat sections on all kinds of websites such as stock investing, sports, news, etc. 

In mailing lists and news groups, a person is identified by the name and e-mail address.



Thousands of people can simultaneously participate in the various available forms of internet chat and conferencing.



Discussions are categorized by topic, enabling people who are interested in a particular topic



Depending on the system, topic groups may be called newsgroups (in UseNet), channels (in IRC), forums, boards, groups, or rooms.

CHAT AND CONFERENCING ETIQUETTE: Here are some general rules of etiquette. 

Remember the limitations of the conference call medium.



Watch your behavior.



Check your spelling and text before you click send.



Don’t send copyrighted material to mailing lists or newsgroups.



Don’t try to manage the conversation unless you are the mailing list manager, channel operator, or other person in charge.



Consider whether you really need to post a message to the entire list



Remember that you are talking to real people, not to computers.

Safety while chatting: 

Never give out your personal information in a chat room.



Never agree to meet a stranger in person whom you met in a chat rom.



When you’re asked to enter or sign up for a chat nickname, choose a name that doesn’t give away your personal information.



Check the terms and conditions, code of conduct, and privacy statement at the chat site before you begin to chat.



Don’t allow your children to use chat or conferencing system without supervision. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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

Don’t believe everything you read.

Ways to use chat effectively: 

Chatting in real time enable you talk to the person you talk to the person you are interested



Chat rooms are very popular with singles and, this is not surprising at all.



If you want endless conversations with the person that you are related.



When you have understood all the rules of a chat, you might find yourself with nothing to say.

ONLINE CHATTING: The term online chat is used to refer to any type of communication that needs the interest to take place. This type of communication usually offers real time and direct transmission of text based messages. The internet offers great opportunities to interact and communicate with friends and people from all over the world. Chatting over the internet can be done with a group of people in a chat room over the internet can be done with a group of people in a chat room, or with the person you are playing an online game.


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IMPORTANT QUESTIONS: TWO MARK QUESTIONS: 1. What is IP? 2. Expand TCP/IP 3. What are the types of domain? 4. Define client 5. Define server 6. What are the types of server and clients? 7. What is DNS? 8. Explain downloading E-mail 9. Expand MIME, UCE, UBE 10. What is reporting spam? 11. List any two types of viruses 12. Define IRC 13. What is instant message? 14. Define web based chat 15. What is online chat? FIVE MARK QUESTIONS: 1. Explain internet communication protocols 2. What is IP address and how to finding the IP address? 3. Explain types of domain 4. Explain sending and receiving email 5. What is harmful effects of viruses? 6. What are the types of online chat and conference? 7. What is online chatting? TEN MARK QUESTIONS: 1. Discuss about connecting to the internet 2. Explain about types of servers and clients 3. What are the functions working in exchanging E-mail? 4. How to fighting spam in details? 5. Explain types of computer viruses.


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UNIT – II Messaging – Usenet Newsgroup – Internet Relay chat (IRC) – Instant Messaging - Voice and Video Conferencing. Web Browsers- Internet Explorer- Features of Internet explorer6- Searching the Internet- online help and tutorials- Browser settings. MESSAGING: Messaging (also called electronic messaging) is the creation, storage, exchange, and management of text, images, voice, telex, fax , e-mail, paging, and Electronic Data Interchange (EDI ) over a communications network. In programming, messaging is the exchange of message s (specially-formatted data describing events, requests, and replies) to a messaging server , which acts as a message exchange program for client programs. There are two major messaging server models: the point-to-point model and the publish/subscribe model. Messaging allows programs to share common message-handling code, to isolate resources and interdependencies, and to easily handle an increase in message volume. Messaging also makes it easier for programs to communicate across different programming environments (languages, compilers, and operating systems) since the only thing that each environment needs to understand is the common messaging format and protocol. 1. Short Message Service (SMS) is a text messaging service component of phone, Web, or mobile communication systems. It uses standardized communications protocols to allow fixed line or mobile phone devices to exchange short text messages 2. Multimedia Messaging Service (MMS) is a standard way to send messages that include multimedia content to and from mobile phones. It extends the core SMS (Short Message Service) capability that allowed exchange of text messages only up to 160 characters in length. USENET NEWSGROUP: News groups: 

Usenet newsgroups are electronic discussion groups in which you can share information and opinions with people all over the world.



In Usenet newsgroups you can reply to articles you have read and publish (“post”) your own articles for others to read.



Newsgroups differ widely in subject and style, ranging from casual chat to serious Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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News group hierarchies: Newsgroups are organized and grouped by title using hierarchical compound names such as rec.sport.basketball.college. Here, rec specifies recreational topics sport specifies a subgroup of recreation. The big eight mainstream hierarchies are:  Comp: anything related to computers (e.g., programming languages, operating systems, hardware)  Humanities: art, music, literature, philosophy, classical studies, etc.  Misc: an assortment of topics that don’t fit in any other  News: pertaining to the administration and discussion of Usenet software, protocols, policies, etc.  Rec: recreation and hobbies of all kinds  Sci: academic discussions of science and, to a lesser extent technology.  Soc: history, culture, religion, politics, lifestyle, and other topics of social interest  Talk: debate and extended discussion. Accessing newsgroup: If the internet service provider (ISP) offers access to a news server we can read newsgroups with newsreaders. Reading newsgroups: 

Articles posted on newsgroups are distributed over the internet by news server.



These servers store and forward Usenet articles, and provide articles to users running news clients or newsreaders.



News servers and news readers communicate by using an internet protocol called the network news transfer protocol (NNTP).



Some of the popular newsreader software is Netscape messenger, outlook express, Netscape mail and newsgroups.



One of the most popular and reliable ways to read Usenet newsgroups on the web is through Google.



Once you have a news reader set up on your computer, reading and positing to newsgroups is relatively simple.

Difference between newsgroup and mailing lists: Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

26


S.No Newsgroup 1 A newsgroup uses servers to store messages that readers can download with a newsreader client. 2 With a newsgroup, you can use your newsreader to browse a list of the subject

Mailing lists A mailing list sends a copy of the email to the membership of the list.

In mailing lists, the messages are transmitted directly to each subscriber in the form of email messages. A newsgroup is a discussion based Mailing lists require their users to internet community that discusses provide an email address to receive topics via a news server. information.

3

Finding interesting newsgroups: There are ten thousand of Usenet newsgroups are available to read and post to find the ones that are right for you and start sharing information with people all over the world. Find newsgroups that interest you. Here are some newsgroups to read while you are getting up to speed in Usenet. 

Rec.humor.funny (www.netfunny.com) is the first a USENET newsgroup that provides you with daily, editor-selected jokes.



News.announce.important

is

the

charter

and

positing

guidelines,

news.announce.newgroups. 

Google groups at groups.google.com, searching for a specific subject that may be coming up on a variety of groups or are you looking for posts by a particular author. This is a very useful to for Usenet lovers.

Open the complete list of newsgroups in a newsreader window and search for topics using keywords. Once you find a group you can usually double-click on the name of the group to open a window containing the most recent postings. Usenet netiquette: 

Think before you post.



Remember that your newsgroup correspondents are human beings whose culture, language, and humor may be different to your own. Be careful with slang or local terminology.



Many people pay for connectivity by the minute, and the longer your post is, the more they pay. People don’t object to paying to download a long and interesting or entertaining post. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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

The cost of delivering a newsgroup article is paid by the sender and by the owner of every news server that carries your newsgroup.



Remember that posting anything to a newsgroup people are going to read your words not only today but, probably in years to come if you don’t want your spouse/partner/boss/mother/enemy to know your “secret”, don’t post it to a news group.



Limit line approximately 65-70 characters.

Creating newsgroups: 1. A request for discussion on creation of a new newsgroup should be posted to news. Announce. Newsgroups, news. Groups, and any other groups or mailing lists at all related to the proposed topic if desired. 2. The name and character of the proposed group and whether it will be moderated or un moderated 3. Group advocates seeking help in choosing a name to suit the proposed charter are looking for any other guidance in the creation procedure can send a message to [email protected]; a few seasoned news administrators are available through this address. INTERNET RELAY CHAT (IRC): Introduction: Internet relay chat was first started in august of 1988, when jarkko oikarinen, an employee of the department of information processing science at the university of oulu, finland. What is IRC? IRC (instant relay chat) is a multi-user, multi-channel chatting system. We can use the computer and talk through typed messages with either one person or many people from all over the internet, all in real time. IRC network There is no “main IRC network”. Original network has split into hundreds of smaller networks. Each IRC network is independent of the others. Most popular networks are DALnet, EFnet, IRCnet, Undernet and quakeNet.


28


DALNET: started in 1994 as an alternative to the overburdened networks of the time, DALnet has grown into a vibrant community and is widely regarded as the most “friendly” of the major IRC networks from 25 users in July 1994, the number of users grown to over 142,000 users during peak hours. The home page of DALNet is www.dal.net. EFNet: EFnet or Eris-Free network is a major IRC network, with more than 35,000 users. It is the modern-day descendant of the original IRC network. The home page of the EFnet is www.efnet.org. IRCNet: IRCNet stands for internet Relay Chat Network. Many IRCNet servers state that IRC is a privilege, not a right. That defines the characteristics of network usage .the home page of the IRCNet is www.ircnet.org UnderNet: the Undernet is one of the largest real time chat networks in the world; with approximately 45 servers connecting over 35 countries and serving more than 1,000,000 people weekly to learn how to connect the Undernet take a look at our help page. The home page of the Undernet is www.undernet.org. QuakeNet: quakeNet is a large IRC network. People from all over the world connect to quakeNet to communicate, organize and hang out you can use any common IRC client to join in or use our web chat application to join directly from your browser. The home page of the quakenet is www.quakenet.org. IRC Servers: 

Computer and software that work like IRC switchboards, letting users connect to them IRC client program are known as IRC servers. IRC servers bind together

in

a

network

to

share

channels

of

communication,

like

communicating with everyone on a single radio frequency. 

Most IRC servers are at universities or ISPs. There are three major networks of IRC servers: Efnet, Undernet, and DALnet.



EFnet: the first traditional and largest net short for Eris free net more that almost 40,000 people all over the world are always connected to EFnet, at any time.



UnderNet: in 1992 this net was evolved. Undernet is smaller than ERnet, and more community oriented alternative networks.



DALnet: one of the oldest nets, it keeps pace with Undernet. It started as a role-playing game alternative network.


29


Three major IRC server nets: EFnet Servers Ir.magic.ca Irc.colorado.edu Irc.c.com.net

UnderNet Servers Ann-arbor.mi.us.undernet.org Austin.tx.us.undernet.org Blacksburg.va.us.undernet.org

DALnet Servers Irc.dat.net Irc.service.dal.net Glass.oh.us.dal.net

IRC Servers ports: When you sign on with IRC, you typically connect to the IRC server at a port in the range 6660-6670.internet Relay Chat, commonly found on ports 6667, 6668, 6669, and 7000, but really, found on most any port. Channels: Users meet in channels, the IRC equivalent of a chat room. When you first connect to IRC, you choose a channel to join. An unlimited number of users can be in a channel. Each channel name starts with a pound sign (#). Some channels are for discussing specific topics there are public, private and secrets “invisible” channels. Nicknames and Chanops: Each IRC users has a nickname, a unique word they have chosen. Each time you connect to an IRC server, you specify a nickname, which you can also change at any time. The nickname should be nine characters or less. Some characters have an atsign (@) at the beginning of their nickname. An @ signifies that a person is channel operator or chanop. The channel operator also referred to as a “chop” or “chanop” on a given channel is considered to ‘own’ that channel. Netsplits and lags: Netsplits: when the connection between two or more servers is lost when this happens, you will see a group of people suddenly quit at the same time. Servers usually join back together by themselves after a few minutes. Lags: when your messages take longer than expected to show up at the other side. This usually more prominent when people are connected to separate servers in a network. Direct client to client (DCC): Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

30




The direct client to client (DCC) protocol enables you to pass files or chat with other users by connecting two IRC clients directly without going through a central server.



You use DCC when you want to hold a private conversation with another person.



Do not accept DCC messages from someone you don’t known.



People have been known to send offensive pictures or computer viruses.

Chanserv and Nickserv: Chanserv: Allows for registering of channels. It makes channel management easy, as well as permission control easy. Please sure to follow our channel policy when choosing a channel. To get a list of available command use: /msg ChanServ HELP Nickserv: Allows you to register your nick to prevent people from using it to impersonate you, or just from stealing your nick. To get a list of available commands use: /msg NICKServ HELP Create your own IRC Channel: You can easily become the operator of your own IRC channel. You can create your channel by typing/join #channel-name where the channel name doesn’t already exist on that network. /join funfunfun When you create a channel, you are automatically made the operator of the channel you can invite friends across the internet to join the channel. /topic #quantum this channel is about Einstein If you need to sign off the channel, or wish to give up operator status, you can assign operator status to someone else with the /op command. You can make more than one person operator want: /op ivan /op pierre /op jane Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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The /mode command lets you designate a channel that you have created to be secret or private. /mode #mychannel +s /mode #mychannel +p. mIRC: 

mIRC is a featured internet relay chat client for windows that can be used to communicate, share, play or work with others on IRC networks around the world, either in multi-user group conferences or in one-to-one private discussions.



It has clean, practical interface that is highly configurable and supports features such as buddy list, file transfers, multiserver connections. SSL encryption, proxy support, spoken messages and more.



mIRC also has a powerful scripting language that can be used both to automate mIRC and to create applications that perform a wide range of functions from network communications to playing games.



mIRC has been in development for over a decade and is constantly being improved and updated with new technologies



mIRC is shareware not freeware.


32


INSTANT MESSAGING (IM): What is instant messaging? 

It allows two or more users to exchange text, image, and audio messages in real time, provided that users have compatible messaging services. Communicating by IM is also called chatting.



IM clients that facilities connection between specified known users (often using “buddy list”, friend list”, or contact list”).



Instant messaging includes additional features for example, users can see each other by using web cameras, or talk directly for free over the internet using a microphone and head phone or loudspeakers.



The most popular instant messaging applications include windows (MSN) messenger, yahoo messenger, AOL instant messenger (AIM), ICQ.

Features of instant messaging: Most IM programs provide these features: 

Instant messages- send notes back and forth with a friend who is online



Chat- create a chat room with friends or co-workers



Web links- share links to your favorite websites



Video- send and view videos, and chat face to face with friends



Images- look at an image stored on your friends computer



Sounds- play sounds for your friends



Files: share files by sending them directly to your friends



Talk: use the internet instead of a phone to actually talk with friends.



Streaming content: real time or near –real-time stock quotes and news



Mobile capabilities: send instant messages from your cell phone

Benefits of instant messaging: Instant messaging software can provide several benefits: 

The immediacy provided by instant communications.



Avoiding swapping list members with unnecessary messages



Value – added features, such as sharing desktop applications, use of web cams, etc.



Instant messaging fans appreciate the immediacy of communications it provides, which can be particularly valuable when working on small-scale concrete tasks. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

33


Possible problems in IM: 

Need to install an appropriate IM client.



Lack of interoperability across IM clients from different vendors



Dealing with interruptions.



Lack of an archive of discussions, missing messages when away.



Difficulties in following discussions when used by several people.

VOICE AND VIDEO CONFERENCING: Internet phone: 

Internet phone is another word for “VoIP” (voice over Internet Protocol) or “Internet calling”. Internet phone is a great way for people to save money on their monthly phone bill.



You can get internet phone service for your business phone as well your home phone. With internet phone, you use your high speed internet connection to make and receive phone calls.



A category of hardware and software that enables people to use the internet as the transmission medium for telephone calls.



For users who have free, or fixed price internet access internet telephony software



There are many internet telephony applications are available some like coolTalk and NetMeeting,



Internet telephony products are sometimes called IP telephony, voice over the Internet (VOI) or voice over IP (VOIP) products.

How does internet phone work? 

Using an internet phone is just like using a regular phone the phone numbers, dial tone and phone area codes are all the same.



The difference between traditional phone service and internet phone service is how the internet phone service connects you to the world



Internet phone uses the internet to connect your phone calls to the public phone network. First, your internet phone has to convert your voice into data if you are interested in how VoIP works, you can read more about the mechanics of VoIP.



Internet phone uses large banks of computers in data centers to transfer the sound of your voice from computer to computer



This is an extremely efficient process that improves as computer technology. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Voice conferencing: It can be PC-to-PC or PC-to-phone, with two or more people in the conversation. It replaces conference calls, which get expensive when they include many people over long distances. Video conferencing:  Video conferencing in its most basic form is the transmission of image (video) and speech (audio) Back and forth between two or more physically separate locations.  Video technology uses the same technology as IRC, but also provides sound and video pictures. It enables direct, face to face communication across networks.  A video conferencing system has two or more parties in different locations. Hardware requirement for video conferencing: 1. Camera: the camera captures live images to send across the network. 2. Visual display: it displays the images of the people taking part in the video conference. 3. Audio system: it includes both microphones to capture audio from the endpoint and loudspeakers to play back the audio received from other endpoints across the network connection. 4. Compression: videos are very bandwidth intensive and they take a long time to load to compress and decompress video and audio data, allowing transmission across a network connection in near real time. 5. User interface and control system: The user interface allows the users to control interactions for example placing calls, storing and locating numbers and adjust environment settings such as volume. Benefits of video conferencing: 

It can improve work quality



Increase productivity



Reduces costs



Improves communication



Groups can meet more frequently



Critical meetings can be convened in less time



More faculty and staff can be involved



Closely resembles traditional class room based education Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

35




Faculty and staff needs can be met more quickly through just in time training.



More faculty and staff can be trained faster without increasing training resources.



Guest lecturers can be easily integrated into the course



Enable any site to be provider of the learning activities



Video conferencing is cost effective when you consider the travelling costs for traditional training.

Getting voice and video hardware: For internet phone, voice, video conferencing, you need computer with high-speed internet connections, microphone and speakers; you also need a web camera connected to your computer. Making phone calls over the internet: To make a free call using an internet phone, you might have to download free call software or use a soft phone from an internet phone provider website. Some internet phone programs are separate programs. Internet Phone program PCCall DialPad Net2Phone Go2call

Features PC to PC -

website PC to Phone PC to Phone PC to Phone PC to Phone

www.pccall.com www.dialpad.com www.net2phone.com www.go2call.com

Voice and video conferencing using instant messenger programs When you really want to stay in touch over a long distance, a simple phone call or voice chat pales in comparison to a face-to-face video chat. The most important voice and video conferencing using instant messenger programs are ICQ, AOL instant messenger (AIM), yahoo messenger, and windows messenger Yahoo messenger: Yahoo instant messaging application is one of the most widely used programs of its kind and allows you to chat in real time with users of the same program yahoo messenger has many features most voice chat mode and the ability to see when you contacts are online you can also host private or public reference sending files play games. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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The most important voice and video conferencing:  Making internet phone calls with ICQ  Making internet phone calls with AOL instant messenger  Voice conferencing in yahoo messenger  Video conferencing in yahoo messenger  Conferencing with windows messenger and MSN messenger  Making PC to PC phone calls with windows messenger  Making PC to PC calls with windows messenger  Video conferencing in windows messenger WEB BROWSERS: Web browsers are software applications that are used to access the information on the World Wide Web (WWW) that is stored on web servers. Web servers are used to store, manage and supply the information on the World Wide Web. The main web browsers in use are Microsoft internet explorer and Mozilla Firefox. Browsers display the text and graphics accessed from websites and provide tools for managing information from websites. The most popular browsers for windows are as follows: 1. Internet explorer (IE) 2. Netscape navigator (NN) 3. Opera 4. Mozilla Firefox 5. Google chrome 6. Safari, etc. Connecting to the internet To connect the internet the user needs to have the following components. 

Telephone line is a medium through which the data is transferred from one computer to another.



Modem or network card.

ISP (internet service provider): An

internet

service

provider

(ISP)

is

a

company

that

provides

a

telecommunication connection to the internet that allows user to “be online” the


37


connection may be provided in many different forms it could use existing telephone lines, fiber optic cable or the user has to use a modem and dial a phone number. Types of internet connections: Dialup connection Dialup services use a modem and phone line to dial into a point to point protocol (PPP) account on an internet provider’s computer. Most ISPs support modems at speed of 14.4 kbps, and 56 kbps. You connect only when you want to use internet services and disconnect. Cable modems: Transmit the data over the cables that bring television to homes business. Many users share the bandwidth. This sharing can reduce the bandwidth available to each person when use the system simultaneously. ISDN (integrated services digital networks): Integrated services digital networks, is a system of digital phone connections which has been available for international communication. This system allows voice, video and data to be transmitted simultaneously across the world using end –to-end digital connectivity. DSL (digital subscriber line): Digital subscriber line it is a medium for transferring data over regular phone lines and can be used to connect to the internet. However, like a cable modem, a DSL circuit is much faster than a regular phone connection even the wires it uses are copper like a typical phone line ADSL (Asymmetric Digital Subscriber Line): Asymmetric digital subscriber line uses an upgraded phone line, all digital technology and supports simultaneous internet processing and phone use. ASDL is optimized for the way many people use the internet more downloads than upload. DSS (Digital Satellite System): Digital Satellite Systems or direct broadcast satellites get internet information by satellite. We receive data from the internet at a high speed via satellite. We receive data from the internet at a high speed via satellite. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Wireless internet Access: Wireless internet access requires attaching a special radio modem to the laptop. To acquire satellite access satellite dish is needed. INTERNET EXPLORER: Microsoft internet explorer (IE) has become the standard for browsing web pages online. All windows based computers come preinstalled with internet explorer, and versions appear on other platforms. Opening Microsoft internet explorer: Start -> All Programs -> Internet Explorer, or look for Internet Explorer icon on the desktop or quick launch. FEATURES OF INTERNET EXPLORER 6: 

Internet Explorer 6 offers extended synchronized multimedia integration language (SMIL) 2.0 HTML+TIME (timed interactive multimedia extensions) functionality.



Internet Explorer 6 provides additional support for the document object model (DOM) level 1 and cascading style sheets, level 1 (CSS1) standard.



Web developers can intercept navigation errors with the navigate error event of the web browser control.



Internet Explorer 6 implements the on mouse wheel event, allowing web developers to add localized mouse wheel functionality to their pages



Rendered elements that overflow in width now shows ellipses.



My pictures toolbar makes web pages more available to the casual user. The toolbar appears when the user moves the mouse over large images.



The media bar toolbar integrates media into the browsing experience. Users can select and play sound media from the browser without opening a separate application.



Users can now set the level of privacy they want when browsing by specifying whether web hosts can collect client information through cookies.

SEARCHING THE INTERNET: Searching means locating particular information on the website. The internet provides a wealth of information on virtually any topic to helps users locate information, may websites provide search engines that explore the internet and maintain searchable records containing information about website content. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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The various search engines are as follows: Google: www.google.com Yahoo: www.yahoo.com Lycos: www.lycos.com Altavista: www.altavista.com Alltheweb: www.alltheweb.com Ask.com: www.ask.com LiveSearch: www.livesearch.com When the user enters a word or phrase, the search engine return a list of hyperlink to sites that satisfy the search criteria. Each search engine site has different criteria for narrowing searches, such as publishing date, language and relevance. IE6 has a built in Meta search engine that is accessed by clicking the search button in the task bar. ONLINE HELP AND TUTORIALS: Online help: Online help can be used at any time if you’re stuck with a particular task and just need reminding. All GPPs have online help usually by pressing a key. Clicking on an icon on the toolbar or from a list on a menu. Online tutorial: An online tutorial is a program which you often use when you are learning the basics of a GPP. It leads you step through the basics of creating and editing documents through a set of lessons. Web browsers are complex pieces of software with rich functionality. Although browser designers make every effort to produce user friendly software, use still used time to familiarize themselves with each web browser and its particular features. BROWSER SETTINGS: Enable Microsoft Internet Explorer 6  From the browser tools menu select “Internet Options” Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

40


 Select the security tab.  Pick the “internet zone” icon.  Push the “custom level.”Button”.  Scroll down the settings list to the scripting item  Under the “Active Scripting” item, choose the enable radio button.  Push OK and Yes to confirm and close the security settings.  Dialog box, then OK again to close the internet options dialog box.  Refresh the current page. To delete cookies in internet explorer 6:  Run Internet Explorer.  Open the tools menu  Select Internet Options to open the Dialog box.  Click the “delete Cookies” button.  Click Ok. Increasing the size of the text Some users find screen text easier to ready by increasing the size that the text is displayed. To do this in Microsoft Internet Explorer, go to the ‘View menu’ and then select either ‘larger’ or ‘largest’.

Changing the display on the screen Internet explorer provides other ways in which you can fine-tune how a Directgov page displays on your screen. For example you can remove the background colors and choose which colors to have text, links and visited links displayed. You can make these changes by: Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

41




Going to the tools menu at the top of the page



Selecting ‘Internet Options’ from that menu



Clicking the ‘Accessibility’ button

Then tick the box ‘Ignore colors specified on web pages’. Then click the ‘OK’ button. This will switch off the background colors in directory. Un-tick the box use windows colors you can then specify which colors you would prefer to be displayed for the text and for links. You can also specify colors to be used for links your have previously visited and links.


42


IMPORTANT QUESTIONS: ONE MARK QUESTIONS: 1. What is messaging? 2. Define newsgroup 3. What is accessing newsgroup? 4. Define IRC 5. What is IRC networks? 6. What is instant messaging? 7. Define video conferencing 8. What is web browser? 9. What is ISP ? 10. How to opening the Microsoft internet explorer? 11. What are the various search engine? FIVE MARK QUESTIONS: 1. Discuss accessing group 2. Discuss finding interesting newsgroup 3. Explain nicknames and chanops 4. Write short notes on mIRC 5. Define IRC servers 6. What are the features of IM? 7. What is web browsers? 8. What are the features of internet explorer? 9. Explain online and tutorials 10. Explain the changing on display on the screen TEN MARK QUESTIONS: 1. Explain in newsgroup in details 2. Explain in details Internet Relay Chat 3. Explain in details Instant messaging 4. Discuss about voice and video conferencing 5. Explain about browser settings in details


43


UNIT III Overview – Web Security, Privacy, and site-blocking – Audio and Video on the web – Creating and Maintaining the Web – Web site creation concepts – Web Page Editors. OVERVIEW: WEB SECURITY, PRIVACY, AND SITE-BLOCKING: It is important to understand the functionality and features of your web browser, whether it is internet explorer Mozilla Firefox, and Google chrome or apple safari, to name a few. Enabling some web browser features may lower security. Often, manufactures will enable features by default to improve the computing experience. Secure your browser: Always enable the pop-up blocker for each browser. If a program requires pop-ups be enabled there is an “exception” feature so that those site URLs are manually added. Never enable the “remember my password” feature of a browser. Internet explorer has the option to automatically save a copy of an encrypted web page to your hard drive. Since encrypted pages usually require a password, you could be saving a copy of your password to your hard drive along with the page, which is a bad idea also the browser can auto fill your username and password after typing a few letters. To turn off these features. Select tools-> internet options from the menu bar. 

Select the advanced tab. From the security section, deselect “do not save encrypted pages to disk”



Select the “content tab. Click the settings button under the auto complete category. Uncheck “forms” and “username” and passwords on forms”



Click ok to exit the option manager

Cookies: 

Cookies are messages that web servers pass to the web browser when we visit internet sites.



The browser stores each message in a small file, called cookie.txt.



When we request another page from the server, the browser sends the cookie back to the server. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

44




This file typically contain information about our visit to the web page, as well as any information



Cookies are most commonly used to track web site activity. When we visit some sites, the server gives a cookie that acts as the identification card.



In this way a web server can gather information about which web pages are used the most and which pages are gathering the most repeat hits.



Cookies are also used for online shopping. Online stores often use cookies that record may personal information we enter as well as any items in the electronic shopping cart, so that user don’t need to re-enter this information each time we visit the site.



Servers also use cookies to provide personalized web pages. When we select preferences at a site that uses this option, the server places the information in the cookie to create a customized page for us.

Plat form for internet content selection (PICS) 

The PICS specification enables labels to be associated with internet content



It was originally designed to help parents and teachers control what children access on the internet, but it also facilities other uses for labels, including code signing and privacy.



The PICS platform is one on which other rating services and filtering software has been built



PICS is a cross industry working group whose goal is to facilitate the development of technologies to give users of interactive media, such as internet



PICS members believe that individuals, groups and business should have essay access to the widest possible range of content selection products, and a diversity of voluntary rating systems.



In order to advance its goals PICS devise a set of standards that facilities the following:

Self-rating: Enables content providers to voluntarily label the content they create and distribute Third- party rating: enables multiple, independent labeling services to associate additional labels with content created and distributed by others. Services may devise their own labeling systems, and the same content may receive different labels from different services.


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Ease –of-use: enables parents and teachers to use ratings and labels from a diversity of sources to control the information that children under their supervision receive. Content rating services safesurf and RSAC (Recreational Software Advisory Council) 

The two rating systems that are built into Netscape Netwatch are Safesurf and the Recreational Software Advisory



Microsoft’s content advisor includes only RSAC’s system.



Safesurf is a parents group trying to make the internet a safe and useful tool for children.



RSAC is a nonprofit corporation and its mission was to issue a rating system for computer games, and it later extended its game rating system to the internet.

PICS-reading browsers: Navigator’s Netwatch and internet explorer’s content advisor: Both internet explorer and Netscape navigator- far and away the most popular internet browsers. to set up RASC filtering in internet explorer (version 4 and 5) click on the view or tools menu, select internet options and the content tab and click on the enable button. If you haven’t used the facility before you will be asked to enter a supervisor password, which will prevent anyone else from changing the settings. After that you can work your way down the list on the ratings tab setting the level for each one with a simple slider control. The approved sites tablets you set up a list of websites that can be viewed, or blocked Setting up Netscape is a little more involved since it users both RASC and Safesurf, moreover the initial settings and changes are made online. Unrated Web Sites: For safety reasons, the newer versions of internet Explorer allow you to block unrated websites. Website ratings allow you to block some websites that includes certain types of objectionable materials. Some websites have no rating to be safe you can block all websites that are not rated. Security in internet explorer: Configuring IE Security Zone: Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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To configure security zone settings 1. On the Tools menu, click Internet Options, and then click the Security tab.

2. Click a Security Zone to select it and view its current settings To specify custom security settings for the selected zone, click the customize level button. To set the options for a particular security level back to their original settings, click the default level button. For restricted sites, you need to click custom level and then click a level in the reset to list internet explorer divides your internet world into zones, so that you can assign a web site to a zone with a suitable security level. 

Local intranet zone: the local intranet zone includes all sites inside an organization’s firewall (for computers connected to a local network).



Trusted sites zone: the trusted sites zone can include all internet sites that you know are trusted. For example, the trusted sites zone might contain corporate subsidiaries sites or the site of a trusted business partner.



Internet zone: the internet zone includes all sites on the internet that are not in the trusted sites or restricted sites zones.



Restricted sites zone: the restricted sites zone can include all sites that you do not trust.

Changing a zone security level in internet explorer Here’s how to customize your security zone settings:


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1. Open the desktop, and then tap or click the internet explorer icon on the taskbar. 2. Tap or click the Tools button, and then tap or click Internet Options 3. Tap or click the Security tab and customize your security zone settings in these ways: 

To change settings for any security zone, tap or click the zone icon, and then, move the slider to the security level that you want.



To create your own security settings for a zone tap or click the zone icon and then tap or click custom level and choose the settings that you want.



To restore all security levels to their original settings tap or click the Reset all Zones to default level button.

Assigning Websites to IE Security Zones To assign a web site to a security zone, the following these steps: 1. on the Tools menu in Internet Explorer, click Internet Options 2. Click the Security tab. 3. Click a security zone Local intranet zone, trusted sites zone or restricted sites zone. 4. If you clicked Local intranet, click Advanced. 5. Click Sites, and then type the internet address for the web site that you want to add to this zone. Setting other IE security policies Controlling IE security warning messages Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Internet explorer will interrupt a download when using HTTP based resources on a secure HTTPS page by displaying a security warning. To control IE security warning messages, follow these steps: From the “tool” menu, select “Internet Options”. The internet options dialog appears. Select the “Security “tab” click on the “custom level” button toward the bottom. The security settings dialog appears. To delete cookies follow these steps: 1. Open internet Explorer by clicking the Start button. In the search box, type Internet Explorer and then in the list of results click Internet Explorer. 2. Click the Tools button, point to safety, and then click Delete browsing history. 3. Select the cookies check box, and then click Delete To block or allow cookies 1. Open internet explorer by clicking the start button. In the search box, type internet Explorer and then in the list of results click Internet explorer 2. Click the Tools button, and then click Internet options 3. Click the privacy tab, and then under settings move the slider to the top to block all cookies or to the bottom to allow all cookies and then click ok. Blocking cookies might prevent some web pages from displaying correctly. To block or allow cookies from specific websites 1. Open internet explorer by clicking the start button. In the search box, type internet Explorer and then in the list of results click Internet explorer 2. Click the Tools button, and then click Internet options 3. Click the privacy tab, and then under settings move the slider to a position 4. Click sites 5. In the address of website box, type a website address and then click block or allow. Blocking websites with IE content advisor Enabling and disabling content advisor in IE To activate the content advisor open internet explorer. Chose Tools-> internet options. Click the Content tab, and then click the Enable button. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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In internet explorer, choose Tools -> Internet options. Click the Content tab. Click Setting button to display this dialog box.

In the password box type your supervisor password, and then click Ok. On the Ratings tab, select the language or violence ratings category. Content advisory window you will have four tabs given below Ratings: this section allows a user to set the ratings levels for language and violence. As you move the button slider from left to right Approved sites: enables the user to approve or prohibit a specific URL from being viewed. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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General: Allows the user to perform additional tasks such as setting up a supervisor password and implement other system settings. Advanced: Allows a user to obtain ratings bureau or specify PICS rules. Select a category to view the rating levels and click ok. In internet Explorer click on Tools and internet Options. Click on the Content tab and on the Disable button.

Adding and removing rating systems in IE 1. Enable the Content Advisor (Tools->Internet option -> Content tab >Enable) 2. On the Tools menu, click Internet Options, and then click the Content tab. 3. In the Content Advisor area click settings. 4. In the Password box, type your supervisor password and then click ok 5. Click the General tab.

6. Click Rating systems. 7. If the rating system you want to add is displayed on the list click it and then click Add. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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AUDIO AND VIDEO ON THE WEB: Playing streaming audio and video An audio file might take more real times to download than the length of the clip being played that is you might spend 10 or 30 minutes downloading an audio clip playback time might be only two minutes Video, which carries much more information than audio. The advent of streaming media changed all that streaming media uses an age-old concept buffering to make viable playback of multimedia content while it is being downloaded. A buffer holds a reservoir of content sufficiently large to smooth out the pumps in playback that may be caused network congestion. Popular audio and video players: The most popular audio and video plug-ins and active controls that can play the most common file formats: RealOne Player RealPlayer: formerly Real Audio Player, RealOne Player and RealPlayer G2, is a cross platform adware media player app, developed by RealNetworks. The media player is compatible with numerous container file formats of the multimedia realm, including MP3, MP4, QuickTime File Format, Windows Media format, and the proprietary RealAudio and Real Video formats. RealPlayer is also available for other operating systems (OS) and Linux, Unix, Palm OS,Windows Mobile and Symbian versions have been released you can download real one player from www.real.com Quick time : QuickTime is a multimedia development, storage, and playback technology from Apple. QuickTime files combine sound, text, animation, and video in a single file. Using a QuickTime player that either comes with a Web browser or can be downloaded from Apple or the browser company, you can view and control brief multimedia sequences. Windows media player: Windows Media Player (WMP) is a software application from Microsoft used to play, store and organize digital audio, images and video. While earlier editions of WMP were released for PC s running a variety of operating system operating systems, including Windows Mobile. Win Amp: WinAMP (Windows Audio MPEG Player) is a program from Nullsoft that allows PC users to play audio files, particularly music, in many popular digital audio


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formats, including MS-Audio, WAV, and MP3. With WinAMP, it is possible to listen to SHOUTcast streaming radio broadcasts. iTunes Match: iTunes Match can be accessed directly from iTunes on desktops and laptops, and from the Music app on iOS devices. The iTunes Match service stores music purchased through the Apple App Store, music imported from CDs and music purchased through services other than iTunes. iTunes Match subscribers are also able to listen to iTunes Radio stations free of advertisements Internet radio: Internet radio (also web radio, net radio, streaming radio, e-radio, online radio, and webcasting) is an audio service transmitted via the Internet. Broadcasting on the Internet is usually referred to as webcasting since it is not transmitted broadly through wireless means. Internet radio involves streaming media, presenting listeners with a continuous stream of audio that typically cannot be paused or replayed, much like traditional broadcast media; in this respect, it is distinct from on-demand file serving. Internet radio is also distinct from podcasting, which involves downloading rather than streaming. Internet radio services offer news, sports, talk, and various genres of music every format that is available on traditional broadcast radio stations Many Internet radio services are associated with a corresponding traditional radio station or radio network, although low start-up and ongoing costs have allowed a substantial proliferation of independent Internet only radio stations. Some of the web sites to link to all categories of web content from music and videos Shoutcast at www.southcast.com internet radio service that offers thousands of free MP3 and AAC radio stations and broadcast around the world. Live365 at www.live365.com listen to thousands of internet radio stations featuring online music in every style, including hip hop. Jazz, new age, rock, classical and more. Playing MP3 Music ‘MP3’ is the abbreviation for MPEG audio layer III (MPEG stands for ‘Motion Picture Expert Group’) it’s a compressed digital audio file. A player stores these files on a memory chip so that you can play it back at your leisure. The MP3 player is the most recent in an evolution of music formats. You will learn more about the technology inside MP3 players and the different types of players available like Windows Media Player, WinAmp, Real One Player and MusicMatch. You can download many mp3 players from www.Mp3.com, www.tucows.com. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Features and Benefits of an MP3 player 

Contains a maintain hard disk drive which can storage huge quantities of data.



MP3 usually contain music, but the format is also used for general audio files such as audio books



MP3 can be listed to with earphones or headphones, or played through speakers via an external amplifier

Finding MP3 music on the web: 

Music tracks, MP3 downloads, and lyrics are all over the internet. The easy availability of free music on the internet has been a source of major controversy for the past several years.



The internet Continues to abound with sites that allows you to find music tracks and download songs and music for free

You can download many MP3 songs search sites are available they are. Beemp3, at www.beemp3.com MP3 Music Mania at www.mp3music4all.com MP3Viper at www.mp3viper.com MP3Fresh at www.mp3fresh.net Emp3 world at www.emp3world.com Playing video on the internet: Prerecorded video Video streaming is becoming extremely popular. More and more websites are starting to stream video online. Several video formats are in use on the internet. Some of the popular types of video file formats used over the internet are AVI (audio video interlaced) MOV (Apple Quick Time Movie), MPEG-4 (.MP4) websites use windows media player, real one player. The most popular websites are www.youtube.com, www.tv.com, www.metacafe.com, www.liveleak.com Live video with webcams: The digital video cameras broadcast from a specific location and often broadcast 24 hours a day. You will find webcams at many popular places like earth cam www.earthcam.com


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Windows media player: Windows media player is the powerful multimedia player included with windows XP. Windows media player not only provides features for enjoying audio and video including DVD if you add a decoder but also supports copying compact discs (CD) to your hard disk in compressed formats and burning custom audio CDs. You can download newest version from the windows media player website ( www.microsoft.com/windows/mediaplayer). Getting started with windows media player: Start windows media player by choosing Start->All Programs->Windows Media player Clicking the windows media player icon on the quick Launch toolbar you see the windows media player windows show in figure.


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Finding files with the media guide: Media guide connects to the windows media website over the internet from which you can view video files content that is updated on a daily basis. Click the media guide button on the toolbar on the left side of the player media player is shows in figure.


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Creating a media library: Windows media player includes the media library, a storehouse for all of your audio and video files to organize your audio and video files windows media player can search your drives for files. It organizes them into lists of audio files, video files, and the addresses of radio stations on the internet.

Finding internet radio stations with the radio tuner: Many radio stations use the internet to broadcast their signal to parts of the world that their antennas could never reach in addition to large scale commercial stations hundreds of little operations are cropping up windows media player brings all of the stations that use the windows media streaming technology to you in the form of a searchable database.


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Realone player: Real one player is a first rate multimedia reproduction system developed by Real Networks. A multifunction player, realone enables you to play Mp3, WAV and RM files and tune it radio stations multimedia channels newsgroups, etc. you can download realone player www.real.com Realone player windows: The following figure illustrates the three environment of the realone player here the media playback pane plays streamed or downloaded clips.

CREATING AND MAINTAINING THE WEB: How to Create and Maintain a Web Page or Website What Do I Need To Create My Webpage?


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1. You’ll need an ISP (Internet Service Provider) to host your site. Most ISPs provide you with a certain amount of space on their servers for you to have your own web presence. Check with your ISP to see how much space you have and if there is a data transfer cap on download. A data cap means if enough people access your web pages and/or download files from your website to exceed the maximum data transfer the ISP will block access to your site until the end of the current billing session or charge you extra at so much per Mb, (megabyte). There are many hosting services out there that will be either free or cost you some money. Most of the free ones will put advertisements on your pages and/or emails through them automatically. This is how they provide the “free” service to you. As a member of the Kingston Amateur Radio Club, (KARC), one of the perks is that you can have your webpage hosted on the KARC’s server. And you also have an email account that can be accessed through your normal email program or through the web. All the examples in these articles will be based on a web page hosted through the KARC. 2. An FTP (File Transfer Protocol) program There are several FTP programs out there and you will use this to transfer your web pages, graphics, and downloadable files to the ISP. Some programs such as Microsoft’s Front Page allows you to do this without using an external FTP program. 3. An idea of what you want to put up on the web. This can be a themed website such as the KARC’s which has information about Amateur Radio, a site to showcase a hobby, your travels, a how to site to show others how to do things such as build a mini key for your radio, the possibilities are endless. Most ISP does have a caveat about what you can place or cannot place on your site. Read their Terms of Service” 4. A graphics program Pictures and graphics can eat up a lot of your web space. A typical cheap digital camera (under $100.00), now takes pictures in the 2-6 Mb per picture. And the resolution is huge, 1-2 anywhere up to 3600x2400 pixels for example. Most computers are operated at a screen resolution of 640x480, 800x600, or 1024x768 for example. You will need a graphics program to resize your photos and other graphics and make the file size as small as possible. 5 A program to create your web pages Any ASCII, (American Standard Computer Information Interchange), text editor such as Microsoft’s Notepad can be used to create your pages. This of course will Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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mean that you will have to learn all the syntax and command structure of HTML, (Hyper Text Markup Language), etc. Or you can use WYSIWYG, (What You Se Is What You Get), Web creation programs such as Microsoft’s Front Page, Dreamweaver, or others. You can also use programs such as Microsoft’s Word or Open Office which can convert files to HTML format for you. How a web site work The directory or folder on your ISP which will be the starting point for your web page is what we will call the “Home” directory. In the Home directory we can place all our pages and graphics. Our web pages will normally use the file extension of .htm or .html. On some sites you will see pages using .asp, .php, and other extensions. We will be using .htm or .html only for our articles. The first page that a person will see when they go to your web site will be the index.htm or index.html page. This page will load by default when a user types a web site URL (Universal Resource Locator) or IP (Internet Protocol) address into their web browser. The index page then contains links to other pages on your site or links to other sites. For example if you type http://www.ve3kbr.com into your browser, it will take you to the introduction page of the KARC. There is lot of behind the scenes on how this happens but we will not worry about how it happens. In the case of the KARC, this page gives us information on the next club meeting, last time the web pages were updated, Club and RAC (Radio Amateurs of Canada) logos and an “Enter” link. Clicking on the Enter link opens up the page which is basically a table of contents for the KARC site. Clicking on links here takes us to pages of sub topics, downloadable files such as the Club’s Monthly Newsletter, or to external sites not belonging to the KARC.

Planning Your Web Page Organization of your web site structure right from the beginning will make it easier for you to maintain the site as you add pages and graphics. What starts out as a simple page 1-3 to showcase or pass information can grow very quickly into a monster that becomes very difficult too look after. For instance you could have all your HTML and graphic files in the Home directory. For only a few pages and graphics this will work but the more pages and graphics you add it becomes a nightmare to look after. An example web site using only the Home directory for all files Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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An example web site using only the Home directory for all files Create your website structure like a book with chapters: a table of contents, each topic their own chapter, and a chapter containing all the graphics. The graphics chapter then has sub chapters for each main chapter of the book. The easiest way is to have one or only a few pages for your main topics of your sight in the Home directory and place all your graphics in a directory called graphics or images. For pages off your main pages, create sub directories according to topics, and if need be sub directories within them. Do the same for the graphics directory. Create sub directories dependant on what pages the graphics relate to. Not only will this make it easier for you to maintain your web site but when you are creating your pages it makes it easier to create the links and links to graphics. If you have several topics and sub topics, for example the KARC web site, then it is best to use a structured directory/folder style which will make it easier to find pages you need to update and or their images.


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A

structured

web

site

using

sub

directories

In this case we only have the index.htm file and topic directories. In the images director/folder there is a thumbnail folder which mirrors the layout of the images folder names. The thumbnail folders hold mini pictures for use on the pages which link to the full size pictures which saves time in loading pages, especially on dial up services. More on this later on in the tutorials. If you create your web site directory on your computer and have the same directory Structure in your Home directory on the server transferring files will be easy. Here are some links to get you started on building your web page and how the internetworks: How stuff works "How Web Pages Work" Have you ever wondered how a Web page works? www.howstuffworks.com/web-page.htm


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How stuff works Internet infrastructure http://computer.howstuffworks.com/internet-infrastructure1.htm HTML Tutorials: Tutorials using on the Doteasy.com website. make-a-web-site http://www.make-a-web-site.com/ w3Schools.com http://www.w3schools.com/html/default.asp http://www.w3schools.com/web/default.asp for advanced subjects http://www.htmlcodetutorial.com/document/ Small Planet Communications http://www.smplanet.com/webpage/webpage.html HTML Made Really Easy .....................very good http://www.jmarshall.com/easy/html/ WEB SITE CREATION CONCEPTS: Planning your website When it comes to website planning there are at least five key items to consider when coming up with your website blueprint. If you make sure to take time to think through these five things your chances for creating a successful website increase exponentially. 1. Determine the goals for your website. What are you trying to accomplish? 2. Pinpoint your target audience and try to understand what their interests are. How you can provide them with the valuable information they are looking for? 3. What will your call-to-action be? Determine what you want your website visitors to do once they land on your site. 4. Figure out how you will get your readers to easily navigate through your site in order for them to complete your call-to-action 5. Create a list of keyboards that you will use throughout your site in order to move your web pages up the ranks search engines like Google, Bing, etc. Basic Steps in Creating Site: 

Basic steps in creating a site plan the structure of the site, so that we have an idea what information will be on at least the home page and other key pages.


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

Using the text editor or web page editor, create the pages of the site and save them as HTML files. Use a graphics editor to create or view graphics for the pages.



Using browser view the HTML files created. Check the contents and the links



Publish the web site by putting all of its files on a web server.



Using the browser view the web pages as stored on the web server

Planning of website (i)

Why are you building this site?  The first step of website planning should be deciding on the purpose of the website  Determine what it is that you wish to accomplish with the website  Taking the time to clearly define the purpose of the website will affect how successfully you reach the goals you set for the project

(ii)

Determine target audience

What is your target audience?  Ask yourself “who is going to be looking at my site?  Now ask, “What technologies will your visitors have?”  When planning a website you need to assess what the target audience will be, what their technologies their systems will have and what their computer experience before you can decide on your website technologies.  Determining your target audience during the website planning stage will give you a wealth of information that can be used as the website is further developed. (iii)

Website Technical Considerations

Ask yourself,” what technologies do I need?”  The website technologies you will require will depend on the type of website you are building and what type of audience you have decided to target and accommodate.  Have your list of website technologies required ready before you move to the next step, securing hosting.


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(iv)

Website Hosting Costs:

Website hosting costs are influenced by website planning.  Your hosting costs are influenced by all the above. When planning a website be sure that the web host has room to grow with your site.  The features included with a slightly more expensive hosting package that you will need in the future? (v)

Website Budget

Ask yourself,” What is my budget?”  When planning a website, budget can be a determining factor as to what features the website will have.  Seriously assessing what you can do yourself and for what you need external help with will affect the website budget.  As you can see, website planning has a number of steps to go through before actually building the website. General Tips for Designing a Website Here are a few website design tips for creating a professional website. Keep it simple: all you need are crisp photos or images and simple text that are well balanced on each page, with a few hyperlinks and a few buttons to navigate to other pages on your website. Don’t bury the main point: put the most important on your homepage and secondary information only a click away. Working with images: make sure your image file sizes are small so that they load seamlessly and your page appears instantly While we’re on the subject, no pop-up windows: people don’t like to have their web-viewing experience interrupted by pop-up windows Color schemes: choose a color scheme with three mild colors for your web pages. Fonts: choose a font that simple and easy on the eyes. Pages: limit your page length to just one page scrolls. Blogs and articles can be longer but no one likes scroll down a page too far to find the information they want. Don’t use icon links: that is every link should be a text link including the buttons at the top of a pages it’s okay to have a rectangular button or other button shapes.


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Issues to be aware of when planning the web site Text size: a certain trend among designers believing that small text gives a web page a sleek appearance and provides more space per “page” for actual content sometimes results in the use of unreasonable small font sizes. Colors: choose a color scheme with three mild colors for your web pages. One should be your background. Writing for an international audience: if you write a web page and put it up on the World Wide Web, then you have instantly created a globally page. Privacy: the privacy policy tells you how we use personal information. Newer include personal information about people on the web pages without their consent. For example, names, postal address, email addresses and phone number. Maintenance: with regular website maintenance your site will run smoothly. Regular visitors are looking for what is new, so provide them with new and exciting information products or features. Accessibility: web accessibility means that people with disabilities can perceive, understand, navigate, and interact with the web, and that they can contribute to the web. Creating your site: Elements of a web page A basic web page has four main elements: hypertext markup language, text, graphics and links. Hyper text markup language (HTML): 

Hypertext markup language is the code that browsers like Netscape Navigator and Microsoft Internet Explorer use to “read” a web page. A web page is a Hypertext Markup Language document.



Hyper text markup language documents are saved with the file extensions .html or .htm.



When you save your web page in composer, the .html extension will be automatically added.

Text: 

Text consists of headings; descriptions, directions, and information that you wish to include in your web page.



Text can be added to a web page by typing directly onto the open composer page.



As much as possible, keep text short and to the point. Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Graphics: 

Web page graphics are images files (photographs, icons, pictures, cartoons, animations) that you can insert into your web page.



Graphic files are used as backgrounds, bullets, page dividers, signposts, illustrations, and sometimes, just for fun.



Web graphic files typically carry the file extension .gif or .jpg.



There are many “readymade” free graphics collections on the web.

Links: 

Links are connectors.



Both text and graphics can be linked.



Links are usually used in three ways:



Links can connect different parts of one long web page.



You can do this in composer by creating “Targets”.



Links can connect different pages of the same web site.

Adding Items to your Web pages You can add items to your web page the following items are to be followed: Video Files: Embedding a video into a web page used to be a real challenge in the early days of the web. Most people now have broadband, and although there are still many video formats, the most commonly used method to embed video today is via the Flash player and an .flv file Audio Files: Audio files in the web pages so that your readers can listen to the audio Animated GIFs: When you see a web graphic spinning, blinking, fading in and out, or otherwise putting on a little show, chances are it’s an animated GIF. Shockwave: Shockwave multimedia platform used to add animation and interactivity to the web pages.


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JavaScript: In today’s web design, JavaScript is a must-have component. Aside from its functionality JavaScript can enhance user experience by creating transitional effects such as fading and sliding animation. Flash: Flash is a software technology for creating and managing interactive multimedia web page applications like web sites, animations, movies, games, advertisement banners and more. It gives you almost unlimited options in the design of your pages. Databases: The web site content isn’t actually sitting in files on the server; it is sitting in tables and columns in a database. A website with its content stored on the file system is often Referred to as a static website where a database driven website is often referred to as a dynamic. Java: There are lots of applications and websites that will not work unless you have java installed, and more are created every day. Java is fast, secure, and reliable. Forms: Form on a webpage allows a user to enter data that is sent to a server for processing. A form is a section of an HTML document where you put input controls (text boxes, check boxes and radio buttons). Tools Needed to Develop the Site The components that make up web pages are the following: 

Text



Pictures



Animated graphics



Audio files



Video files



Animation files



Forma and database information Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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

Text editor



Drawing programs



Clip art gallery



Sound or video equipment

HTML Editors: An HTML editor is a specialized piece of software that assists in the creation of HTML code. Similar to text editors such as Notepad and text Edit, HTML allow users to enter raw text. HTML can be edited by using a professional HTML editor like: table (Popular Web Editors) Web Editor

Price

Characteristics

kompoZer

free

The best free editors is KompoZer, it is designated for non-technical computer users who want to create an attractive website without needing to know HTML.

Macromedia

Under $399

Dreamweaver remains one of the most popular professional web design programs available. It offers a lot of power and flexibility for both designers and developers. The program makes it easy for designers to create visually attractive, interactive web pages without having to know HTML or JavaScript.

Microsoft Front Under $ 199 page

It can be used to create web sites FrontPage is a WYSIWYG (also described in Glossary) editor, meaning that you can create the web page as you want it to look on the screen, and the program adds the HTML source code necessary to make sure that the page looks right in a web browser.

Netscape Composer

Netscape Composer lets you create your own web pages and publish them on the web. The language of the web pages is HTML

Dreamweaver

Adobe GoLive

free


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NetObjects Fusion

Under 109.5

$ Fusion is a very powerful HTML editor. It combines all the tasks you need to get your website up and running including development, design, and FTP.

Microsoft Expression Studio Ultimate

Under 349.0

$ Expression studio Ultimate combines Expression Web with Expression Design, Expression Blend, Encoder Pro, and Sketch Flow to give you a full graphic, video, and web design suite.

Database Driven Sites: Database Driven web site is one that uses database for collecting and storing information. What information it can be? Email addresses, contact info, clients list, products list, listings of real estate property, trade offers, images, and links, etc. How does it work?  For example, you have a static HTML web site for your business with posted information about the company, products or services, clients, and there is contact form.  If you have strong HTML skills you update site without problems each time you need it. Otherwise you hire a webmaster or use maintenance services of a web design company.  You store your products, clients, and contacts info in word or Excel files.  Probably you store emails that you receive from contact form in word or Excel files.  Usually database driven websites have admin panel with user friendly interface where you can manage the site content, i.e. add, edit, or delete.  Requests sent from contact form can be saved in database for further use, you can edit them, group, and sort. You can create pictures gallery on your site and update it easily. Publishing your Site: The final phase of creating a website is publishing your pages. To place your pages on the web, you need a web server. Commonly called hosts, web servers allow you to transfer and store files, including HTML documents, images and multimedia files. Unless you have your own Web server, you need to find a server to host your pages. Some examples of webhost are: www.godaddy.com Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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www.1and1.com www.virtualempire.com Maintaining your Own Server The various items to require setting up and maintaining your own web server:  A computer with high speed internet connection  Web server software  The setup fees and monthly charges required when you use your own web server are substantial. Web Hosting Service:  A web host is the company that provides the server space for your web pages.  You will be uploading your website files to your host.  This is how a website becomes visible on the internet.  They also provide you with e-mail addresses ([email protected])  Scripts for forums, blogs, chat rooms, feedback forms, etc. a website cannot without a host.  The web hosting service providers an internal environment for hosting static websites or small-scale web applications. Free Hosting service:  Free website hosting is a free non-paid web hosting service. There are many web hosts who provide such domains to anyone who wants to make website.  Some of the popular free web hosts include blogger and Word press. When you make your websites with these free website hosting services, your website gets such name as www.blogspot.com and www.wordpress.com.  There are various lists of free web hosting sites available nowadays: For example: www.freehosting.com www.5gbfree.com www.freehostia.com


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Benefits of Free Website Hosting: There is this single biggest advantage of free website hosting and that is it comes free without any cost. Now if you are amazed at why these free web hosting companies let you make a website free of cost then you may rest assured that they do not make any loss n this business. WEB PAGE EDITORS: Introduction: Web editor is a web tool that you can use to make your own website. Web page editor is a HTML editor a software program that inserts HTML code as you create a HTML file. Some editors will provide a word processing GUI enabling users to create HTML documents without knowing any HTML code. As a web editor you would research, write and check the images, text and other media published on your employer’s website. For example you might maintain a college website, local authority public information pages or a news organizations multimedia service. The most important web page editors are as follows: Netscape Composer: is a WYSIWYG (stands for What You See Is What You Get) HTML editor initially developed by Netscape Communications Corporation in 1997. If you do not have Netscape on your home computer you can download it for free from the Netscape site. Go to www.netscape.com Adobe Go Live: Adobe GoLive was a WYSIWYG HTML editor and web site management application from adobe systems. You can download a trail version at www.adobe.com Macromedia Dreamweaver: Adobe Dreamweaver is software used for web development. It is a WYSIWYG web design and development tool. And it allows the less technical people to write web pages without needing to know coding or HTML. Microsoft FrontPage: With Microsoft FrontPage, the user has the capability of creating and positing web pages on the internet. With FrontPage the user has the capability of either the WYSIWYG editor, which the user to create WebPages without any programming or for advanced users, to the program in straight NTML. Editing pages with Netscape composer Creating a new page To create a new page in Netscape composer, follow these steps Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Choose File ->New ->Highlighting ->composer Page. A composer window containing a blank page opens

Editing a page: To edit a page you are currently browsing in navigator Choose File -> Edit Page Saving a Page: Go to File and select Save. Give your file a meaningful name consisting of 8 characters and the extension of .htm and save it into the designated folder. Setting the background, Text, Links Colors To set the colors scheme for your page, go to the Format menu and choose Page Colors and Background.

Setting the page Title and properties In order to change the title of your page: 1. Go to the menu bar and choose Format -> Page Title and Properties. A dialog box will appear. 2. In the title section enter your page title, click OK.


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Editing Pages with FrontPage FrontPage is a web site editing program published by Microsoft. It is designed to make it easy for people to create and publish web sites. When you first start FrontPage, it will automatically open a new blank page. If at any other time you need to create a new page. Select -> File -> New -> Page from the menu. The normal page icon automatically selected from the general category. Click the OK button.

Templates: A template is a pre designed page that can contain page settings, formatting, and page elements. FrontPage 2002 provides several default page templates, or you can create your own. Some examples of the page templates that come with FrontPage 2002 are: Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Bibliography: created a bibliography page that references printed or electronic works. Feedback form: create a page where your site visitors can submit comments about your web site, products, or organizations. Search page: create a page where site visitors can search for keywords across all documents in a web site. Conformation form: create a page to acknowledge the receipt of site visitors Style template: create pages with various layouts such as a page with a narrow leftor right-aligned body. Setting the background, Text, and Links Colors Select Format -> Background. Here is the dialog box will appear select background and a text color.

Setting the page Title and properties 1. Choose from the menu, FILE: Page properties 2. Click the custom tab.


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Title: adds a descriptive title margins can enhance the appeal of your pages by adding whitespace to the top and the left side of a web page. Margins: margins can enhance the appeal of your pages by adding whitespace to the top and left side of the web. Meta Tags: Meta tags make it possible to provide specialized information about the document. Inserting Hyperlinks: Type the text that you want your reader to see. Highlight the text. Click the insert Hyperlink

Themes Themes can quickly add color, graphics and a common layout to your web pages. Open a web page and select Format -> Theme from the menu bar or right-click on the page and select theme.


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Editing pages with Dreamweaver: Adobe Dreamweaver is a site building and publishing tool appropriate for intermediate to advanced users that allows you to create and edit web pages and applications using a graphical interface and built in advanced design and coding features. This section describes dreamweaver8. Creating a New Page Begin by creating a new page 1. From the menu, choose File ->new. (or) use the start UP page and choose New HTML page. Choose a Blank page and HTML then click Create.


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Formatting text In the Dreamweaver Design work area enter your text. Select it and from properties panel set formatting attributes for your text, such as font, color, size, etc.

Inserting images: To insert images to your site Insert-> Image. From the pop-up window choose an image from your computer and insert it into the page. In the image properties panel you can set different preference such as name, size, alternative text, etc.


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From the select image source dialog box navigate to find the image file that you want to insert and click on the filename. Then click ok.

Inserting Links: Hyperlinks, or links, are the elements on a web page that can be clicked on and that transfer a user to another web page or file. In Dreamweaver, you can select a text or an image in your web page to be a link. Click on your web page where you want to insert the link. From the insert menu, choose Prof. Charles E. Raj, Department of Computer Science & Applications | SUN Arts & Science College

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Hyperlink.

you can also select the insert link button from the insert common tool panel icons. This will also bring up the insert Hyperlink dialog box.

Formatting Tables: In the design view of the Document window, place the insertion point where you want the table to appear. Select insert, table from the insert menu or choose the table button in the common category of the insert bar.


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The common category on the insert bar locates the insert table button the insert table dialog box appears you can navigate from box to box by using the table key.

Frames: Frames are used to distribute the data in a web site. They help to keep some parts straight such as key are, as the logotype and the browser bar, while the others can change. To create a frame you first need to open a file it can be new or an existing one after this you need to go to the Insert menu, HTML and Frames. If we click on left, a new frame will be created in the Left side of the current file.


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Creating rollovers: A rollover is an image replace by another when the mouse is over it. This kind of image is used on menus and buttons. If you want to insert a rollover, you need to go to Insert menu Image Objects, and then Rollover Image. In the new window specify the original image and the one that will substitute the former.

Flash button: There is another set of special images similar to rollovers that are used to create menus, these are file flash buttons. To insert a flash button you need to go to the Insert menu Media and Flash Button option and you will see this dialogue box.


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Layers: Layers are square that can be placed wherever you want in the page, we can insert HTML content in them. Those layers can be hidden and overlapped between them. Layers can be inserted in a page through the Insert menu, and then selecting the Design object option and Layer. Once the layer is inserted, you can edit its attributes by selecting it.


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TWO MARKS QUESTIONS: 1. Define cookies 2. What is internet zone? 3. What is real player? 4. What is quick time player? 5. What is live video with webcams? 6. What is ftp? 7. Define website work? 8. What are the steps available in creating site? 9. Define animated GIFs 10. What is forms? FIVE MARKS QUESTIONS: 1. Explain in detail PICS 2. How to configure security zone settings? 3. What is blocking website with internet content advisor? 4. Explain about most popular audio and video players 5. What is a real one player window? TEN MARKS QUESTIONS: 1. Explain in detail web security and privacy 2. How to creating and maintaining a web site? 3. Explain in detail windows media player 4. Explain in detail website creation concepts 5. Discuss about web page editors in Microsoft front page 6. Explain in detail Dreamweaver


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Internet and Its Applications-UNIT I-II-III (thiruvallur university)

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