COMPUTER NETWORK AND WEB TECHNOLOGY

What is a network?

This is a group or system of interconnected people or things

What is a computer network?

This is a group of computing devices that are connected together to share data and resources

What is data communication?

This is the transmission of data and information between two or more computers

What are the ways that data is transmitted between 2 or more computers?

By upload and download

Define upload

This Is the process by which data is sent from your to another computer on the network or internet

Define download

This is the process by which data is received on your computer from another computer on the internet or network

What are the types of network?

Local Area Network (LAN)

Metropolitan Area Network (MAN)

Wide Area Network (WAN)

What is a local area Network?

This is a computer network that interconnects computers within a limited space area such as schools, homes, labs, and internet Cafe

What is a metropolitan area network?

This is a computer network that is large enough to extend to areas such as cities and campuses and can be found in regions larger than that covered by a local

What is a wide area network?

This is a computer network in which the computers connected may be far apart, even In different countries. E.g the internet

What is a mobile network?

This is a global communication network that is interconnected wirelessly by transceivers at fixed locations called cell towers or base stations.

What are radio signals?

These are electromagnetic radiation that includes light and infrared waves

What is a transceiver?

This is a device that is used to transmit and receive information through a transmission medium. It is a combination of a transmitter and a receiver

What are the types of mobile networks?

2G,34, and 4G-LTE. The G stands for generation

What are the features and problems of the 2G mobile network?

• Text messaging, multimedia messaging, internet access, caller ID and the sim card

• The problem associated with 2G is phone calls dropping and slow data transmission rate

What are the features and problems of the 3G mobile network?

• All of 2G plus web browsing, emailing, video downloading, picture sharing, and other smartphone technology.

• The problem associated with 3G is that there is a major limitation in network coverage

What are the features and problems of the 4G-LTE mobile network?

• All of 3G plus significantly faster speeds and increased network coverage

• The association with 4G-LTE is issue relating to the network coverage

What is a wireless network technology?

This is a technology that can connect to a network without the use of a cable or cord.

What are the wireless network technologies?

Bluetooth, WI-FI, and Hotspot

What is Bluetooth?

This is a wireless network technology that provides wireless connectivity using radio waves.

What is Wi-Fi?

A.K.A wireless fidelity, this is a wireless network technology that provides high-speed wireless access to the internet or network

What is Hotspot?

This refers to a public area as large as many square miles or as small as a room that offers internet access over a WAN.

What are the 3 levels of privacy?

Intranet, internet, and extranet

What is an intranet?

This is a private network based on Internet standards, accessible only to those within a business or organization. Hospitals use it to allow employees to access sensitive information like patient and employee records.

What is an extranet?

This is a type of intranet that allows users outside the organization such as suppliers to have limited access to the intranet. A valid username and password is required to gain access.

What is an internet?

This is a globally accessible wide-area network that provides information and communication facilities made accessible through Internet Service Providers (Ips).

What is an iPS?

This is a company that provides internet access from the country's main internet infrastructure to a company or organization

Define the term encryption

This is the process of encoding data or information to prevent unauthorized persons from accessing it

What is a transmisson media?

These are mechanisms by which computing devices are connected together. They may be physical cables or wireless media such as infrared, Wi-Fi, Bluetooth, etc

What is a wired network?

This is a network that uses a wired medium such as twisted pair cables, coaxial cables, and optical Fibre to transfer data between connected devices.

What is a wireless network?

This is a type of network that uses radiowaves Instead of physical cables as the transmission medium.

What are the wired transmission mediums?

Twisted pair cables, coaxial cables, and Fibre optical cables

What are the types of twisted pair cables?

Shielded and unshielded twisted pair cables

What makes up a twisted pair cables?

This is composed of 8 copper wires twisted in pairs to reduce interference and enclosed in a plastic covering

What is the most popular form of transmitting data?

Telephone wires

What are unshielded twisted pair cables designed to do?

These are designed to limited electromagnetic Interference by the way the pairs are twisted inside the cable

Why are UTP cables popular?

They are:

• Versatile

• Inexpensive

• Easy to install

• Light weight

• Flexible

What are the disadvantages of UTP cables?

1. Their susceptibility to electromagnetic interferences and radio frequency interference.

2. Compared to coaxial and Fibre optic cables their bandwidth is small.

What environments are shielded twisted pair cables best suited for?

Environments where there is a high chance of electric interference examples include radiostations and airports

Define the term broadband

This is the transmission of high quality data broadband width

What are coaxial cables?

These are thickly insulated copper wires capable of high speed transmission

What makes up a coaxial cable?

This is made up of a single copper wire core surrounded by a metal shield to reduce interference and all enclosed in a plastic covering.

What are fibre optic cables?

These are high performance and very high capacity communication media used extensively for a country's internet backbone connectivity it's main cities and towns.

What makes up a Fibre optic cable?

This consists of flexible libres with a glass core and carries information using light.

Where can Fibre optic cable run?

Underground or overhead

Why does electrical interference not occur in Fibre optic cables?

Data is transmitted through them as pulses of light instead of electronic signals.

What are the wireless transmission media?

Microwave, satellite, and infrared

What are microwaves?

These are very small wavelengths of powerful signals that can be projected over long distances over a direct line of sight path between any two points

What is a satellite?

This is a communication device orbiting in space that relays and amplifies radio telecommunication signals to and from remote locations.

What is the difference between a satellite and a microwave?

Instead of using two microwave dish antennae that are close to each other, it uses a satellite located in space.

What is infrared?

This refers to the part of the electromagnetic spectrum at wavelengths that lie between the visible light and microwave portions at frequencies 300GHz up to 430THz

What are the 2 types of infrared?

Line of sight broadcast and scattered broadcast

What is a line-of-sight broadcast?

This is the direct pathway from a transmitter to a receiver and the obstructions that may fall in that path

What is shattered broadcast?

This is a broadcast of infrared transmission that is sent out in multiple directions and bounces off walls and ceilings until it eventually hits the receiver.

What is a hub?

This is a multiparty device that connects many computing devices together

How does a hub work?

It repeats the data received from one of its ports to all other ports. Every computer linked to the hub ‘hears' everything any of the other computers say but ignores anything that is not made for them.

What is a router?

This is a the traffic cop of a network that directs data from the modem and sends it to the different devices that are connected to it. It is used to connect 2 networks together

What is a switch?

This is an intelligent device that routes incoming data directly to the specific output port that will take it toward its intended audience.

What is a modem?

This is a device that converts signals from analogous digital visa versa

What is another name for modem?

Modulator-demodulator