Web Searching

A primary reason that people use the Web is to search for specific information,including text, pictures,music and video.The first step in successful searching is to identify the main idea or concept in the topic about which you are seeking information.

Type of Search Tools

Search engine     : Find information relate to specific topic

Subjec directory : Classifies web pages in an organized set of categories

Search Engine
>Helpful in locating information for which you do not know an exact Web address or are not seeking    a particular Web site.
>A search engine is helpful in locating items such as:

A program that searches documents for specified keywords and returns a list of the documents wherethe keywords were found.Requires the users to enter a word or phrase, called search text or search query.Each word of the search text is known as keyword.

Result of the search is called hits.

Result  from the search engine can be in the form of:

• web pages
• articles
• Images
• Audio

Video and etc.Some Web browsers contain an Instant Search box to eliminate the steps of displaying the search engine’s Web page prior to entering the search text.

Other techniques you can use to improve your searches include the following:

üUse specific nouns.

üPut the most important terms first in the search text.

üList all possible spellings, for example, email, e-mail.

üBefore using a search engine, read its Help information.

üIf the search is unsuccessful with one search engine, try another.

Subject directory – classifies Web pages in an organized set of categories such as sport or shopping and related subcategories.

•Examples of search tools:

  1. AltaVista,
  2. Yahoo!,
  3. Google,
  4. Excite

>A subject directory provides categorized lists of links arranged by subject

>When click on the category link, the subject directory displays a list of subcategory links

>The disadvantage – users have difficulty deciding which categories to choose as the menus of             links presented

Example:

Web Page Navigation

Surfing the web
→The activity of using links to explore the web

A link
→Can be text or an image.

Text links
→May be underlined and/or displayed in a color different from other text on the page
→The color of the link will change once the link has been visited.

Navigating Web Pages

→Most web pages contain hypertext or hypermedia links.

Hyper Text:

Link in text base document

Hyper Media:

Combines text base linked with graphic , audio, and video link

Tab Browsing

>Most current web browsers support tabbed browsing

>Tabbed browsing allows you to open and view multiple Web pages in a single Web browser

   windows

>Example of tabbed browsing and links:

Web Browser

Type of Internet connection:
1.Dial-Up Connection
2.Broadband Internet Connectionc / Dirrect Connection

Dial-up Connection

There are two types of Dial-up Connection,



1.Conventional Dial-up
2.ISDN( Integrated Service Digital Network

Conventional Dial-up
>To connect to the internet, your computer dials its modem and connect to a modem attach to your computer

• PC has to dial via a phone lines to connect

Characteristic :

• slower but cheaper
• Ties up phone lines
• Relatively secure from hackers

Example: TMNet

ISDN ( Intergrated Services Digital Network
>also transfer data over ordinary telephone lines
>Typically uses two phone lines to transfer data
>ISDN requires a special ISDN modem
>Characteristics of ISDN:

• Faster but price
• Does't ties up phone line
• Used by bussines and individuals

Direct Connection / Broadband Internet Connection



(Always on Connection)

>PC is continually connected to the Internet
>Direct connections are typically broadband
>used in home and office



DSL ( Digital Subcriber Lines )
>Broadband delivered over telephone lines
>Must be less than 3 miles from a switching station
>Transmit over telephone lines but does not ties up the line
>Fast, Direct Internet access via standard telephone lines

>Requires DSL modem

>Example : - Streamyx without WiFi

Cable Internet Services / Cable Modem

>Cable modem: Most widely used home broadband connection

>Provides high-speed Internet access through the cable television network via a cable modem.

Fixed Wireless

>Uses radio transmission towers rather than satellites

>Provides high-speed Internet connections using a dish-shaped antenna to communicate via radio          signals.

Wi-Fi (Wireless Fidelity)

>Data is transmitted through radio waves

>Provide high-speed Internet connections to compatible or properly equipped wireless computers          and device.

>Example : Streamyx with WiFi

Wi-Fi Hotspot

>Wi-Fi hotspot are places thatprovide the user with freeor paid services 

Satellite Internet Services

>Provides high-speed Internet connections via satellite.

>A satellite dish communicates with a satellite modem.

>Broadband option for rural areas:

• More expensive than cable or DSL
• Available in many areas other broadband options are not

Fiber To The Premises ( FTTP )

>Also known as Broadband over Fiber (BoF)

>Uses fiber-optic cable

>Provide high-speed Internet access to house and business users.

>Delivers over fiber-optic cabling all the way to the building:

• Available in limited areas
• Fast but expensive

Cellular Radio Network

>Also known as Mobile wireless

>Access via mobile phone or device

>Offers high-speed Internet connections to devices with built-in compatible technology or computers    with wireless modems.

>Example provider:- Celcom, Maxis, DiGi

Internet Adress

IP Address
>A number that uniquely identifies each computer or device connected to the Internet.
>IP addresses are also referred to as IP numbers and Internet addresses.

IP Usage
>A way to find specific server or computer on the internet or a network
>Provide identity to a computer in a network
>Identify for a particular device/machine on a particular network
>Allows transfers of files and e-mail

IP Structure
>IP addresses usually consists of four groups of number each separated by a period.
>The number in each group is between 0 and 255
>It is 32 bit long ,each group is 8 bits long
>Commonly written in decimal.
>Written, for example, 128.35.0.72

IP Version
>Two versions of the Internet Protocol (IP) are in use:
                      
               – IP Version 4 (IPv4)
               – IP Version 6 (IPv6)

IP Version 4 ( IPv4 )
>IPv4 an address consists of 32 bits which limits the address space to 4294967296 (232) possible          unique addresses.

IP Version 6 ( IPv6 )

>The address size was increased from 32 to 128 bits or 16 octets.

>Provides the potential for a maximum of 2128, or about 3.403×1038 unique addresses

Domain name and IP adress

>People prefer to use easy-to-remember names instead of IP addresses 

>Domain names (a part of the URL) are alphanumeric names for IP addresses.

• e.g.neon.ece.utoronto.ca,www.google.com, ietf.org

>The domain name system (DNS) is an Internet-wide distributed database that translates between          domain names and  IP addresses

Internet Address

>Domain name

•The text version of an IP address

>Generally,

•First portion of each IP address identifies the network

•Last portion identifies the specific computer.

Domain Name System

>IP address and domain name allocation requires central administration to avoid                                    duplication  

>Previously administered by U.S. government contract (NSI)

>In 1998, technical coordination assigned to ICANN (Internet Corporation for Assigned Names and    Numbers).

• ICANN is the official organization that coordinates domain names on the World Wide Web. ICANN is also responsible for approving or denying new domain extensions.

Top-Level Domains ( TLDs )

>The first-level set of domain names are the top-level domains (TLDs)

Generic Top-Level Domains ( gTLD )

>A generic top-level domain (gTLD) is one of the categories of top-level domains (TLDs)                    maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name            System of the Internet.

Internet Service Provider

ISP

Responsibilities of an ISP
>Providing and maintaining a connection to the Internet

>Support the hardware and software needed to service that connection

>To protect their site and network from external threats such as viruses, hacker attacks and other         illegal activities

>Provide 24-hour customer service and technical support

Example of ISP in Malaysia

ISP: TMNet

Products : Streamyx , UniFi, TM Hotspot

ISP : Time

Product : Time Fibre Home Broadband, Time Broadband

ISP: Packet One Network

Products : P1

ISP : YTL Communications

Product : YES

Different Types of Internet Connection

Type of Internet connection:
1.Dial-Up Connection
2.Broadband Internet Connectionc / Dirrect Connection

Dial-up Connection

There are two types of Dial-up Connection,



1.Conventional Dial-up
2.ISDN( Integrated Service Digital Network

Conventional Dial-up
>To connect to the internet, your computer dials its modem and connect to a modem attach to your computer

• PC has to dial via a phone lines to connect

Characteristic :

• slower but cheaper
• Ties up phone lines
• Relatively secure from hackers

Example: TMNet

ISDN ( Intergrated Services Digital Network
>also transfer data over ordinary telephone lines
>Typically uses two phone lines to transfer data
>ISDN requires a special ISDN modem
>Characteristics of ISDN:

• Faster but price
• Does't ties up phone line
• Used by bussines and individuals

Direct Connection / Broadband Internet Connection



(Always on Connection)

>PC is continually connected to the Internet
>Direct connections are typically broadband
>used in home and office



DSL ( Digital Subcriber Lines )
>Broadband delivered over telephone lines
>Must be less than 3 miles from a switching station
>Transmit over telephone lines but does not ties up the line
>Fast, Direct Internet access via standard telephone lines

>Requires DSL modem

>Example : - Streamyx without WiFi

Cable Internet Services / Cable Modem

>Cable modem: Most widely used home broadband connection

>Provides high-speed Internet access through the cable television network via a cable modem.

Fixed Wireless

>Uses radio transmission towers rather than satellites

>Provides high-speed Internet connections using a dish-shaped antenna to communicate via radio          signals.

Wi-Fi (Wireless Fidelity)

>Data is transmitted through radio waves

>Provide high-speed Internet connections to compatible or properly equipped wireless computers          and device.

>Example : Streamyx with WiFi

Wi-Fi Hotspot

>Wi-Fi hotspot are places thatprovide the user with freeor paid services 

Satellite Internet Services

>Provides high-speed Internet connections via satellite.

>A satellite dish communicates with a satellite modem.

>Broadband option for rural areas:

• More expensive than cable or DSL
• Available in many areas other broadband options are not

Fiber To The Premises ( FTTP )

>Also known as Broadband over Fiber (BoF)

>Uses fiber-optic cable

>Provide high-speed Internet access to house and business users.

>Delivers over fiber-optic cabling all the way to the building:

• Available in limited areas
• Fast but expensive

Cellular Radio Network

>Also known as Mobile wireless

>Access via mobile phone or device

>Offers high-speed Internet connections to devices with built-in compatible technology or computers    with wireless modems.

>Example provider:- Celcom, Maxis, DiGi

Internet Services

Type of internet service :

1. World Wide Web (WWW)
2. e-mail
3. Instant Messaging
4. Voice over Internet Protocol (VoIP)
5. Message Board
6. File Transfer Protocol

World Wide Web (WWW)

• The world Wide Web, or Web, consist of a worldwide of electronic document
• Each electronic document on the web is called web page which contain text, graphics, animation, audio, and video
• Web page usually have built-in connection to other documents
• Some web pages are static (fixed); others are dynamic (changing).
• Visitors to a static web page see all  the same content.
• Visitors to a dynamic web page, can customize some or all of the viewed content such as desired stock quotes, weather for a region or ticket availability for flights.
• A Web site is a collection of related Web pages and associated items, such as documents and pictures, stored on a Web server.
• Web 2.0 refer to Web sites that provide a means for users to share personal information, allow users to modify Web site content and have application software built into the site for visitors to use.
• Web server is a computer that delivers requested Web pages to your computer.

E-mail

>The transmission of messages and files via a computer network

• Consist of simple text or can contain attachments, such as documents, graphics, or audio/video clips.
• Some Web sites , such as 'Google' and 'Yahoo!' provide free e-mail services

>E-mail adress

• An e-mail address is a unique name that consists of a user name and domain name that identifies the user.
• Basic form of an e-mail:

                 username@hostname.subdomain.domain     

• A user name is a unique combination of characters, such as letters of the alphabet and/or numbers, that identifies a specific user.
• User name must be different from the other user names in the same domain.

Instant Messaging

>A real-time Internet communications service that notifies you when one or more people are   online and allows you to exchange messages or files or join a private chat room with them.

• Real time means that you and the people with whom you are conversing are online at the same time. 

• Some IM services support voice and video conversations.
• For IM to work, both parties must be online at the same time.

>Popular IM software includes:

• AIM (AOL Instant Messenger)
• Google Talk
• MySpace IM
• Windows Live Messenger
• Yahoo! Messenger

Voice over Internet Protocol (VoIP)

>Voice over Internet Protocol, a technology for making telephone calls over the Internet in       which speech sounds are converted into binary data.

• To connect a calling party to one or more local or long distance called parties.
• VoIP services are also available on some mobile services that have wireless Internet service.

Message Board

>Type of discussion group.

Fail Transfer Protocol

>Is an Internet standard that permits file uploading and downloading with other computers       on the Internet.

• Uploading is the process of transferring documents, graphics and other objects from your computer to a server on the internet.
• FTP is one method, users have to transfer webpages files from their local machine to the server. 
• An FTP server is a computer that allows users to upload and/or download file using FTP.

Summary