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32 Cards in this Set
- Front
- Back
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What is data? |
Data is processed information. |
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What is data communication? |
Data communication is the process in which two or more computer transfer Data ,Information and Instructions. |
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What is data transmission? |
Data transmission is the transfer of data over a long distance without being changed . |
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What are the components used for data transmission and explain them? |
Sender - the person or device that creates the transmitted message.
Medium - the physical path between the sender and receiver
Receiver - the person or device that received the transmitted message . |
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Data and information over a communication Medium such as: |
Telephone lines Fibre optic cable Coaxial cable Microwaves |
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What are the components of Communication? |
Sending Device - the person or device that sends the message Communication device - Connects the sending device to the communication channel . Communication channel - the pathway over which data are transfered between devices Communication Device - connects the communication channel to the receiving device Receiving device - a collection of electronic components that accepts the transmitted message from the channel . |
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What are the wired transmission media and explain them? |
Coaxial Cable - carry electric current and used for television cables and Internet connections. fibres that each transmit light and used in telephone systems because of its speed Fibre optic Cable - Contains a glass fibres that each transmit light and used in telephone systems because of its speed
Twisted pair cable - used for telephone networks but is slowly being replaced by fibre optic cable
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What is a modem |
Modulator - demodulator ,it converts digital signals to analogue signals and back again. |
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List some examples of communication devices and explain them . |
Telephones - use radio signals to send and receive information they do not need a wire because they have a rechargeable battery
Radio - a broadcast medium that uses radio waves
Television - a broadcast medium that is s radio waves to send pictures .
GPS- Stans for global positioning system,it can know your exact location at any given time as long as it has a satellite signal GPS- Stans for global positioning system,it can know your exact location at any given time as long as it has a satellite signalSmartphone - a mobile phone with extra functions. GPS- Stans for global positioning system,it can know your exact location at any given time as long as it has a satellite signal. Smartphone - a mobile phone with extra functions. |
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Describe the fibre optic cable. |
•expensive • fast and error free •a thin piece of glass tubing •the inside acts as a mirror allowing a light beam to pass through it . •consist of thousands of thin-hair strands |
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What does network connected depends on |
It's topology or configuration. |
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What are he rules ogmf LAN topologies ? LAN topologies ? LAN topologies ? |
•line or Bus topology •star topology •Ring topology |
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What is line or bus topology? |
Computers and other devices that are connected by one cable called the backbone .Devices can be connected to any node on any point of the line. Data is sent in packets ,these packets has the sender and receiver's address. If a computer received a message that is not for it us sent along its way but if it belongs it is kept for processing |
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Draw a diagram to represent data communication. |
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What is the physical material along which data travels from one point to another? |
Transmission media |
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The media used depends on the ________ . |
Distance |
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List three advantages of using the three types of Networks. |
Bus / line Topology- •less hardware to set up •easy to add other equipment. •easy to configure Star topology- • if a computer is damaged it will not interfere with the entire system •if a cable is damaged it will not affect the entire system just the one computer •adding new networks is easy . Ring topology- • if a computer is damaged it will not interfere with the entire system •communication us faster than line •requires less cabling so it's less expensive. |
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What are the two types of transmission media and give examples of each . |
Wired or physical media • coaxial cable •fibre optic cable •twisted pair cable Wireless transmission media • Radio signal •Microwave transmission •Infrared Transmission |
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What are the the two main types of Networks and explain ? |
LAN- local Area Network •This is a Network that links devices with the same building or within a small geographical area .WAN- Wide Area Network a small geographical area . building or within a small geographical area .WAN- Wide Area Network a small geographical area .WAN- Wide Area Network WAN- Wide Area Network •A network in which computers in a large geographical area are connected by more than one local area network |
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What is star topology? |
All computers on the network is connected by a central hub .the hub is where computers can connect Data is transmitted the computer in a packet which has the sender and receiver's address. The packet is sent to the hub and from their to the designated computer. a central hub .the hub is where computers can connect Data is transmitted the computer in a packet which has the sender and receiver's address. The packet is sent to the hub and from their to the designated computer. a central hub .the hub is where computers can connect Data is transmitted the computer in a packet which has the sender and receiver's address. The packet is sent to the hub and from their to the designated computer. address. The packet is sent to the hub and from their to the designated computer. address. The packet is sent to the hub and from their to the designated computer. address. The packet is sent to the hub and from their to the designated computer. |
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What is a Ring topology? |
When computers are connected to a cable and that cable forms a loop or ring .Data is passed from one computer to another by Tokens (electronic signal) .for data to be passed by a computer there gas to be a token in its possession. |
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What is wireless LAN? |
A type of LAN which uses radio links to connect to the network instead of a cable .This is due to two components called Access point and NIC (network interface cards ). network interface cards ). network interface cards ). |
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Where can LAN and WAN be found |
LAN can be found in schools .I n a building with many rooms and WAN in a university ,country, state on so on country, state on so on country, state on so on state on so on state on so on |
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What is LAN and WAN |
LAN - local area network A system which connects computers and other devices over a small geographical area. WAN- wide area network A system that connects devices over a large geographical area such as a country .It usually has LAN that makes up WAN |
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plus three advantages and disadvantages of Networks . |
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What is Analogue and Digital signals |
Analogue signals of continuous electrical wave .It changes smoothly over time . Digital signals are expressed in numbers . |
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What signal does a computer use ? |
Digital signal |
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Define the following terms . WWW , Instant Messaging , Emailing ,Video Conferencing , Internet telephony , MMS, WiFi ,Bluetooth, Internet . |
World Wide Web - an information internet based system which enables the users to move from one document to another by hypertext links .
Instant messaging - a system that allows users to send text messages in real time ,meaning they are able to see if their friend for example is online .
E- mailing - electronic emailing enables one to receive and send manageable messages over a communication network.
Video Conferencing - the simultaneous two way video and audio transmissions used by persons in two or more locations.
Internet telephony - the use of internet to exchange spoken words rather than the telephone company and charge rates .
Multiple Media Messaging - standard way to send messages that includes audio , videos , images on so on from one mobile phone to another .
WiFi - a facility that allows devices to connect to the internet .
Internet - a global computer network which a variety of information and communication facilities .
Bluetooth - a standard for the short range wireless interconnection of mobile phones . |
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What is a discussion about a particular subject in a internet site . |
News Group |
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Define the following: Radio signals Microwave Infrared transmission |
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What are the disadvantages of LAN and WAN networks ? |
Highlighted |
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Define the following terms : SMS , Voice mail , group ware . |
SMS - short messaging service ,this is the sending and receiving of messages. Voice Mail - a computer based system which allows users exchange personal voice messages . Group ware - An application soft - An application software designed to help people involved in a common task to achieve their goals . |
