NETWORK
DEFINITION
A collection of other devices and computers connected together via communication devices and transmission media.
COMMUNICATION DEVICES
Modem
Router
Network Card
Hub/Switch
Wireless Access Point
A central communication device that allows computers and devices to transfer data wirelessly among themselves or to transfer data wirelessly to a wired network.
-Enables a computer or device to access a network
-Network card also available in a variety of styles
-Wireless network cards often have an antenna
The name modem means modulator demodulator.A modem is a communications device that can convert analog signals to digital signals and digital signals to analog signals.
Connects multiple computers or other router together and transmits data to its correct destination on a network
A devices that provides a central point for cables in a network and connects several devices in a network together
TRANSMISSION MEDIA
Physical
Wireless
Use wire,cable and other tangible materials to send communication signals
Cellular Radio
A form of broadcast radio that is used widely for mobile communications,specifically wireless modems and cell phones
Microwaves
Communication Satellite
Broadcast Radio
Infrared (IR)
A spacestation that receives microwave signals from an earth-based station,amplifies it,and broadcast the signal over a wide area to any number of earth-based station
Radio waves that provide a high-speed signal transmission
A wireless transmission medium that distributes radio signals through the air over the long distances such as between cities,regions and countries and short distances such as within an office or home
A wireless transmission medium that sends signals using infrared light waves
DISADVANTAGES
Additional load on computer because of resource sharing
There is a danger of hacking, particularly with wide area networks
If something goes wrong with the file server,the whole network is unable to operate
Hard to maintain version control
Managing a large network is complicated because higher technical skills are needed
Purchasing the network cabling and servers can be expensive
Virus can spread to other computers through a computer network
ADVANTAGES
Sharing hardware
Sharing data and information
Facilitating communication
Sharing software
Transferring funds
Cost-efficient and can help protect our system if we properly secure the network
Sharing a single internet connection
Online banking
People can communicate via e-mail, IM, chat rooms and etc
Each computer on the network can have access to hardware on the network
User connected to a network have access
Twisted-Pair Cable
Fibre Optic Cable
Coaxial Cable
Example: Mouse,printer and smart phone, often have an IrDA port that enables the transfer of data from one device to another devices.
-Dial-Up Modem
-Digital Modem : Cable modem, DSL modem, ISDN modem