Overview of the Internet

Today is a rainy day.I feel so sleepy right now,but I have to complete my task today.

Today I will share to you guys about the overview of the Internet.

Actually what is the Internet?

Internet is a world wide collection of networks that links millions of businesses,government agencies,educational institutions,and individuals.

INTERNET has their own pros and contras .Eventhough internet has giving us many information,but if someone use the internet in wrong way,it will have a bad effect.Here are the advantages and disadvantages of the internet.

INTERNET
Advantages	Disadvantages
Software Downloads: You can freely download software like utilities,games,music,videos,movies,etc from the internet	Virus threat: Computers attached to Internet are more prone to virus attacks and they can end up into crashing your whole hard disk.
Information resources: Can find any information on almost any kind of subject that you are looking for by using search engines like Google, Yahoo, MSN, etc.	Theft of Personal information: Your personal information such as your name, address, credit card, bank details and other information can be accessed by an irresponsible people for their own benefit.
E-mail: People can sent messages. It is delivered instantly to people anywhere in the world, unlike traditional mail that takes a lot of time.	Dangers involved when children using the Internet : When children talk to others online, they do not realize they could actually be talking to a harmful person. Plus, there are thousands of pornographic sites on the Internet that can be easily found.
Online Services:          Perform all your transactions online.       Can book tickets for a movie, transfer funds, pay utility bills.        Make a hotel or flight reservation right from your home.	Social disconnect:             People now only meet on social networks             More and more people are getting  engaged with virtual world and drifting apart from their friends and family.

 

And ..how about the Intranet?

•  Intranet ( intra means within) is an internal network that uses internet technologies.
• Network which only available inside an organization or a company.

Intranet also has their own advantages and disadvantages .

Intranet
Advantages	Disadvatages
•          Commercial or confidential data is kept secure within the organization	•          High financial cost incurred by the company when initially implementing the intranet
•          Email remain private and may also be encrypted	•          Connections between an intranet and the Internet potentially compromises security, by allowing virus infections or system hacking
•          High bandwidth. No connection limits unlike the Internet.	•          Staff needs training to ensure workers know how to use the system effectively.
•          Reliable. The company will have dedicated IT personnel to keep things running smoothly.	•          Information overload is another disadvantage because it reduces productivity.

And how about the Extranet ?

•  Extranet is the portion of a company's network that allows costumers or suppliers of a company to access parts of an enterprise's intranet.
• It provides a secure,physical connection to the company's network.

EXtranet
Advantages	Disadvatages
•          Exchange large volumes of data using electronic data interchange (EDI)	•          Extranets can be expensive to implement and maintain within an organization (e.g., hardware, software, employee training costs), if hosted internally rather than by an application service provider.
•          Share product catalogs exclusively with trade partners	•          Security of extranets can be a concern when hosting valuable or proprietary information.
•          Collaborate with other companies on joint development efforts
•          Jointly develop and use training programs with other companies

 There is  some quotes that I want to share..

Thats all from me...see you guys next week😃

Network Topology

Hello guys!

Today I would like share to you about what is network topology?

Network Topology is refers to the layout of the computer and devices in a communications network.

There are three types of network topology:

• Star Network
• Bus Network
• Ring Network

Here are the examples of network topology

Ring Topology

The network topologies has their own differences:

Network topology	Definition	Advantages	Disadvantages
Star topology	All the computers and other devices on the network connect to a central devices,thus forming a star.	·         If one devices fails,only that devices is affected. ·         Easy to troubleshoot and isolate problem.	·         If the hub or switch fails,the entire nework will be inoperabled. ·         More expensive because of the cost of hub/switch
Bus topology	A bus network consists of a single central cable(backbone),to which all computers and other devices connect.	·         Other devices can be attached or detached without disturbing the network. ·         Inexpensive and easy to install	·         There might be distruption when computer or other devices are added or removed. ·         Its difficult to identify the problem if the entire network shut down.
Ring topology	On a ring network,a cable forms a closed loop(ring) with all computers and devices arranged along the ring.	·         Cable fault are easily located,making troubleshooting easier. ·         All the devices in ring topology share the network resources fairly.	·         Data packets must pass through every computer,thus make it slower ·         More difficult to install than a bus network.

Then I have learnt about the classification of network.There are three types of network which are :

• LAN(LOCAL AREA NETWORK)
• MAN(METROPOLITAN AREA NETWORK)
• WAN(WIDE AREA NETWORK)

LAN

MAN

WAN

There are several comparison about these classification:

CRITERIA	LAN	MAN	WAN
AREA OF COVERAGE	Network cover limited geographical area such as closely positioned group of buildings network , network at home, network inside computer laboratory and network in office building  .	A high speed network that connects Local Area Networks in a Metropolitan Area such as a  cities or town.	Network cover large geographical  area  such a countries ,the  continents or the world
NETWORK SIZE	Small size ( in a building)	Larger size ( in a cities or campus)	Largest size (different states or countries)
SPEED	Fastest in data transferring and access time	Slower in data transferring and access time	Slowest  in data transferring and access time
EXAMPLES	-Network inside the computer lab                  - Network around school -Network inside your home	-Surveillance system -Traffic light monitoring system. - Cable Network TV	-Car Navigation System -Video conference -       Intelligent Transportation System ( ITS )
	LAN’s example can be an office whose different departments such as personnel, accounting etc are located in the same building and connected via bus topology using Ethernet cards.	Example of MAN is bank whose different branches in a city like Kuala Lumpur are connected using public telephone exchange and the system are connected with each other using LAN within each branch and different branches are connected using modem and bridges.	WAN’s example is the connection of various branches of American Insurance Group at different countries. These branches are linked using microwave satellite communication system or internet connection. Each branch has its own LAN circuit.
COMMUNICATION DEVICES	- Connected using modems, hubs, switch , router	- Connected using modems, hubs, switch , router	The  connection is made via  satellite communication link or via Internet
COST	Less costly setup and maintenance	More costly setup and maintenance	Costliest setup and maintenance
Network Ownership	Private – owned, controlled and manage by a single person or organization	Private - owned and operated by a single entity such as a government or large corporation	Not owned up any one organization but exist under collective or distributed ownership

Alright, thats all from me.Wait for the next week entry👯

Network Architecture

Friday,29 December2017

Today,I would like to share about what is network architecture?

Network architecture is the configuration of computers,devices and media on a network.
There is two categories of network architecture

• Peer-to-peer network
• Client/server network

Here are the differences between Client/Server and Peer-to-Peer network

  

Category	Client/server	Peer-to-peer
Definition	One or more computers acts as a server,and the other computers on the network request services from the server	Each computer,called a peer,has equal responsibilities and capabilities,sharing hardware(such as a printer),data,or information with other computers on the peer-to peer network.
Size	For medium and large network	For small network fewer than 10 computers
Operating system	Needs a specific operating system such as Windows Server 2008	Does not need a specific operating system
Training	Needs training	Does not need training
Set up	More difficult to set up	Easy to set up
Installation	More expensive to install	Less expensive to install
Implementation	Big corporations or organizations with high security data	Small businesses and home users

Computer Network

What is the computer network?

Today, I would like to share about what topic that I learn in this semester.First topic is Internet Technology and the subtopic is the computer network.

For your information,computer network is  the collection of computer and devices connected together via communication device and transmission media.

Here is the example of the computer network

The other subtopic that I have learn is about transmission media and communication device.

So,what is the communication device and transmisson media?

• Communication device  is any type of hardware capable of transmitting data,instructions,and information between a sending device and a receiving device.
• Transmission media is materials or substances capable of carrying one or more signals in a communication channel.

Guided media

Unguided media

Example of communication devices

Types of communication devices:

Switch

• A connection device similar to a hub but more sophisticated,including functionality that allows it to control and manage data transmissions.

Wireless Access Point

• Allows computers and devices to transfer data wirelessly  among themselves or to transfer data wirelessly to a wired network

Network Card

• Enables a computer or device that does not have built-in networking capability to access a network.

 

                                                                                              Hub

     A connection device that allows multiple connections to the network.

So,that is the some example of the communication devices that I have learnt.

There is  two types of the transmission media which is :

• Guided media
• Unguided media

GUIDED MEDIA	UNGUIDED MEDIA
·         Twisted pair cable ·         Coaxial cable ·         Fiber-optic cable	·         Infrared ·         Broadcast radio ·         Cellular radio ·         Microwave ·         Communication satellite

Advantages and disadvantages of network

Advantages of network	Disadvantages of network
·         Easy communication and speed -          People can communicate efficiently by using a network such as emails,instant messaging, telephony,etc	·         Security threats -          There are hackers who are trying to steal valuable data of large companies for their own benefit
·         Security -          Sensitive files and programs on a network can be password protected and can only be accessed by the authorized users.	·         Expensive to build -          Building a network for large scale organization are very pricey especially to buy and replace cables and other hardware.
·         Ability to share files,data and information -          It can benefit large organizations to maintain their data in an organized manner access for desired people	·         Bandwidth issues -          Heavy users who consume a lot more bandwidth will affect other users.

GUIDED MEDIA

UNGUIDED MEDIA

·         Twisted pair cable

·         Coaxial cable

·         Fiber-optic cable

·         Infrared

·         Broadcast radio

·         Cellular radio

·         Microwave

·         Communication satellite

Advantages of network

Disadvantages of network

·         Easy communication and speed

-          People can communicate efficiently by using a network such as emails,instant messaging, telephony,etc

·         Security threats

-          There are hackers who are trying to steal valuable data of large companies for their own benefit

·         Security

-          Sensitive files and programs on a network can be password protected and can only be accessed by the authorized users.

·         Expensive to build

-          Building a network for large scale organization are very pricey especially to buy and replace cables and other hardware.

·         Ability to share files,data and information

-          It can benefit large organizations to maintain their data in an organized manner access for desired people

·         Bandwidth issues

-          Heavy users who consume a lot more bandwidth will affect other users.