INTERNET SERVICES

WORLD WIDE WEB (WWW)

• Consists of a worldwide collection of electronic documents.

E-MAIL

• Not real-time internet communication.
• Consists simple text (attachment such as graphics, audio, video clips).

INSTANT MESSAGING (IM)

• Real-time internet communication.
• exchange messages or file or join private chat.
• Eg: Yahoo Messenger

VOICE OVER INTERNET PROTOCOL (VoIP)

• Enables users to speak to other user over the internet.

MESSAGE BOARD

• Easier to use.
• Does not require a newsreader.

FILE TRANSFER PROTOCOL (FTP)

• Software use to upload and download file on the internet.

TYPES OF WEBSITE

1. Portal
2. Business
3. Blog
4. Wiki
5. Online Social Network

Explanation about web browser, web adress,web page navigation, web searching

WEB BROWSER

•A Web browser, or browser, is application software that allows users to access and view Web pages.

Example of web browser:
-Firefox
-Internet Explorer
-Opera
-Safari
-Google Chrome

The component of Web address are
-Protocol
-Domain name
-Path
-Web page name

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WEB PAGE NAVIGATION

There are two ways of navigation.

1. HYPERTEXT : links in textbased documents
2. HYPERMEDIA : combines text-based links with graphic, audio, and video links.

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WEB SEARCHING

-There are two different ways of information searching.


      1.SEARCH ENGINE : find information related to a specific topic.

-Result of search is called hits .

HITS : any web site name thet is listed as the result of a search.
-Result from the search engine can be in the form of :

• web pages
• articles
• images
• audio
• video and etc.

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      2.SUBJECT DIRECTORY : classifies web pages in an organized set of categories.

-Examples of search tools:

• AltaVista
• Yahoo!
• Google
• Excite

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what is web browser ?
definition web browser  ?
what is web address ?
what is web page navigation ?
explanation about web page navigation .
what is difference between webpage,website, web server and search engine?

DIFFERENT TYPES OF INTERNET CONNECTION

DIAL UP CONNECTION

-internet connection over phone lines

-much slower than broadband

-generally avoided

example:

             1) Conventional Dail Up

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              2) Integrated Services Digital Network (ISDN)

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BROADBAND INTERNET CONNECTION

-always connected internet

-much faster than dial-up

-several different types

-example:

                1) Digital Subscriber Line (DSL)

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                2) Cable Internet Service/ Cable Modem

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               3) Fixed Wireless

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               4) Satellite Internet Services

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               5) WiFi

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               6) Fiber To The Premises (FTTP)

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               7) Cellular Radio Network

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INTERNET SERVICES PROVIDER

-Internet Service Provider: A company that provides Internet connections and services   to individuals and organizations.

- Access Provider: A business that provides individuals and organization access to the internet for free or for a fee.

-Example: 

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THE INTERNET ADDRESS

IP Address:

ØA number that uniquely identifies each computer or device connected to the Internet.

ØIP addresses are also referred to as IP numbers and Internet addresses.

ØIP address sometimes is called a dotted decimal number or dotted quad.

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IP Version

                      IPv4

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                     IPv6

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OVERVIEW OF THE INTERNET 

ADVANTAGES AND DISADVANTAGES OF INTERNET, INTRANET, AND EXTRANET

NETWORK TOPOLOGY

NETWORK TOPOLOGY

A network topology refers to the layout of the computers and devices in a communications network.

• It refers to the physical and logical layout of a network.

Physical topology: The arrangement of cabling is the physical topology.

Logical topology: The path that data travels between computers on a network is the logical topology.

TYPES OF NETWORK TOPOLOGY

1. STAR NETWORK 
2. BUS NETWORK
3. RING NETWORK

STAR NETWORK TOPOLOGY

Definition: All the computers and others devices on the network connect to a central device, thus forming a star.
Advantages :
👉If one devices fails, only that device is affected.
👉Devices can be added or removed from network with no discruption.
👉Easy to troubleshoot and isolate problem.
Disadvantages:
👉If the hub or a switch fails, the entire network will be inoperabled.
👉Requires more cables than most of the other topologies.
👉More expensive because of the cost of hub/switch.

BUS NETWORK TOPOLOGY

Definition: A bus network consists of a single central cable (backbone), to which all computers and other devices connect.

Advantages:

👉Inexpensive and easy to install.

👉Other devices ca be attached or detached without disturbing the network.

👉Failure of one device usually does not affect the rest of the network.

Disadvantages:

👉There might be disruption when computer or other devices are added or removed.

👉The break in the main cable(backbone) will prevent all systems from accessing the network.

👉It is difficult to identify the problem if the entire network Shut down.

Definition:On a ring network, a cable forms a closed loop (ring) with all computers and devices arranged along the ring.
Advantages:
👉Transmission of data is simple as packets travel in one direction only.

👉Cable faults are easily located, making troubleshooting easier.

👉All devices in ring topolgy share the network resources fairly.Disadvantages:
👉A failure in any cable or device breaks the loop and can take down entire network.
👉Data packets must pass through every computer, thus make it slower
👉More difficult to install than a bus network